/*
  * VP9 compatible video decoder
  *
  * Copyright (C) 2013 Ronald S. Bultje <rsbultje gmail com>
  * Copyright (C) 2013 Clément Bœsch <u pkh me>
  *
  * This file is part of FFmpeg.
  *
  * FFmpeg is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
  * FFmpeg is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
  * License along with FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
 #include "avcodec.h"
 #include "get_bits.h"
 #include "internal.h"

 #include "thread.h"

 #include "videodsp.h"
 #include "vp56.h"
 #include "vp9.h"
 #include "vp9data.h"
 #include "vp9dsp.h"
 #include "libavutil/avassert.h"

 #include "libavutil/pixdesc.h"

 
 #define VP9_SYNCCODE 0x498342
 
 enum CompPredMode {
     PRED_SINGLEREF,
     PRED_COMPREF,
     PRED_SWITCHABLE,
 };
 
 enum BlockLevel {
     BL_64X64,
     BL_32X32,
     BL_16X16,
     BL_8X8,
 };
 
 enum BlockSize {
     BS_64x64,
     BS_64x32,
     BS_32x64,
     BS_32x32,
     BS_32x16,
     BS_16x32,
     BS_16x16,
     BS_16x8,
     BS_8x16,
     BS_8x8,
     BS_8x4,
     BS_4x8,
     BS_4x4,
     N_BS_SIZES,
 };
 
 struct VP9mvrefPair {
     VP56mv mv[2];
     int8_t ref[2];
 };
 

 typedef struct VP9Frame {
     ThreadFrame tf;
     AVBufferRef *extradata;
     uint8_t *segmentation_map;
     struct VP9mvrefPair *mv;

     int uses_2pass;

 } VP9Frame;
 

 struct VP9Filter {
     uint8_t level[8 * 8];
     uint8_t /* bit=col */ mask[2 /* 0=y, 1=uv */][2 /* 0=col, 1=row */]
                               [8 /* rows */][4 /* 0=16, 1=8, 2=4, 3=inner4 */];
 };
 
 typedef struct VP9Block {
     uint8_t seg_id, intra, comp, ref[2], mode[4], uvmode, skip;
     enum FilterMode filter;
     VP56mv mv[4 /* b_idx */][2 /* ref */];
     enum BlockSize bs;
     enum TxfmMode tx, uvtx;

     enum BlockLevel bl;
     enum BlockPartition bp;

 } VP9Block;
 
 typedef struct VP9Context {
     VP9DSPContext dsp;
     VideoDSPContext vdsp;
     GetBitContext gb;
     VP56RangeCoder c;
     VP56RangeCoder *c_b;
     unsigned c_b_size;

     VP9Block *b_base, *b;

     int pass;

     int row, row7, col, col7;
     uint8_t *dst[3];
     ptrdiff_t y_stride, uv_stride;

 
     // bitstream header
     uint8_t keyframe, last_keyframe;

     uint8_t last_bpp, bpp, bpp_index, bytesperpixel;

     uint8_t invisible;

     uint8_t use_last_frame_mvs;
     uint8_t errorres;

     uint8_t ss_h, ss_v;

     uint8_t intraonly;
     uint8_t resetctx;
     uint8_t refreshrefmask;
     uint8_t highprecisionmvs;
     enum FilterMode filtermode;
     uint8_t allowcompinter;
     uint8_t fixcompref;
     uint8_t refreshctx;
     uint8_t parallelmode;
     uint8_t framectxid;
     uint8_t refidx[3];
     uint8_t signbias[3];
     uint8_t varcompref[2];

     ThreadFrame refs[8], next_refs[8];
 #define CUR_FRAME 0

 #define REF_FRAME_MVPAIR 1
 #define REF_FRAME_SEGMAP 2
     VP9Frame frames[3];

 
     struct {
         uint8_t level;
         int8_t sharpness;
         uint8_t lim_lut[64];
         uint8_t mblim_lut[64];
     } filter;
     struct {
         uint8_t enabled;
         int8_t mode[2];
         int8_t ref[4];
     } lf_delta;
     uint8_t yac_qi;
     int8_t ydc_qdelta, uvdc_qdelta, uvac_qdelta;
     uint8_t lossless;

 #define MAX_SEGMENT 8

     struct {
         uint8_t enabled;
         uint8_t temporal;
         uint8_t absolute_vals;
         uint8_t update_map;

         uint8_t ignore_refmap;

         struct {
             uint8_t q_enabled;
             uint8_t lf_enabled;
             uint8_t ref_enabled;
             uint8_t skip_enabled;
             uint8_t ref_val;
             int16_t q_val;
             int8_t lf_val;
             int16_t qmul[2][2];
             uint8_t lflvl[4][2];

         } feat[MAX_SEGMENT];

     } segmentation;
     struct {
         unsigned log2_tile_cols, log2_tile_rows;
         unsigned tile_cols, tile_rows;
         unsigned tile_row_start, tile_row_end, tile_col_start, tile_col_end;
     } tiling;
     unsigned sb_cols, sb_rows, rows, cols;
     struct {
         prob_context p;
         uint8_t coef[4][2][2][6][6][3];
     } prob_ctx[4];
     struct {
         prob_context p;
         uint8_t coef[4][2][2][6][6][11];
         uint8_t seg[7];
         uint8_t segpred[3];
     } prob;
     struct {
         unsigned y_mode[4][10];
         unsigned uv_mode[10][10];
         unsigned filter[4][3];
         unsigned mv_mode[7][4];
         unsigned intra[4][2];
         unsigned comp[5][2];
         unsigned single_ref[5][2][2];
         unsigned comp_ref[5][2];
         unsigned tx32p[2][4];
         unsigned tx16p[2][3];
         unsigned tx8p[2][2];
         unsigned skip[3][2];
         unsigned mv_joint[4];
         struct {
             unsigned sign[2];
             unsigned classes[11];
             unsigned class0[2];
             unsigned bits[10][2];
             unsigned class0_fp[2][4];
             unsigned fp[4];
             unsigned class0_hp[2];
             unsigned hp[2];
         } mv_comp[2];
         unsigned partition[4][4][4];
         unsigned coef[4][2][2][6][6][3];
         unsigned eob[4][2][2][6][6][2];
     } counts;
     enum TxfmMode txfmmode;
     enum CompPredMode comppredmode;
 
     // contextual (left/above) cache

     DECLARE_ALIGNED(16, uint8_t, left_y_nnz_ctx)[16];
     DECLARE_ALIGNED(16, uint8_t, left_mode_ctx)[16];
     DECLARE_ALIGNED(16, VP56mv, left_mv_ctx)[16][2];

     DECLARE_ALIGNED(16, uint8_t, left_uv_nnz_ctx)[2][16];

     DECLARE_ALIGNED(8, uint8_t, left_partition_ctx)[8];
     DECLARE_ALIGNED(8, uint8_t, left_skip_ctx)[8];
     DECLARE_ALIGNED(8, uint8_t, left_txfm_ctx)[8];
     DECLARE_ALIGNED(8, uint8_t, left_segpred_ctx)[8];
     DECLARE_ALIGNED(8, uint8_t, left_intra_ctx)[8];
     DECLARE_ALIGNED(8, uint8_t, left_comp_ctx)[8];
     DECLARE_ALIGNED(8, uint8_t, left_ref_ctx)[8];
     DECLARE_ALIGNED(8, uint8_t, left_filter_ctx)[8];
     uint8_t *above_partition_ctx;
     uint8_t *above_mode_ctx;

     // FIXME maybe merge some of the below in a flags field?

     uint8_t *above_y_nnz_ctx;
     uint8_t *above_uv_nnz_ctx[2];
     uint8_t *above_skip_ctx; // 1bit
     uint8_t *above_txfm_ctx; // 2bit
     uint8_t *above_segpred_ctx; // 1bit
     uint8_t *above_intra_ctx; // 1bit
     uint8_t *above_comp_ctx; // 1bit
     uint8_t *above_ref_ctx; // 2bit
     uint8_t *above_filter_ctx;
     VP56mv (*above_mv_ctx)[2];

 
     // whole-frame cache
     uint8_t *intra_pred_data[3];
     struct VP9Filter *lflvl;

     DECLARE_ALIGNED(32, uint8_t, edge_emu_buffer)[135 * 144 * 2];

 
     // block reconstruction intermediates

     int block_alloc_using_2pass;

     int16_t *block_base, *block, *uvblock_base[2], *uvblock[2];
     uint8_t *eob_base, *uveob_base[2], *eob, *uveob[2];

     struct { int x, y; } min_mv, max_mv;

     DECLARE_ALIGNED(32, uint8_t, tmp_y)[64 * 64 * 2];
     DECLARE_ALIGNED(32, uint8_t, tmp_uv)[2][64 * 64 * 2];

     uint16_t mvscale[3][2];
     uint8_t mvstep[3][2];

 } VP9Context;
 
 static const uint8_t bwh_tab[2][N_BS_SIZES][2] = {
     {
         { 16, 16 }, { 16, 8 }, { 8, 16 }, { 8, 8 }, { 8, 4 }, { 4, 8 },
         { 4, 4 }, { 4, 2 }, { 2, 4 }, { 2, 2 }, { 2, 1 }, { 1, 2 }, { 1, 1 },
     }, {
         { 8, 8 }, { 8, 4 }, { 4, 8 }, { 4, 4 }, { 4, 2 }, { 2, 4 },
         { 2, 2 }, { 2, 1 }, { 1, 2 }, { 1, 1 }, { 1, 1 }, { 1, 1 }, { 1, 1 },
     }
 };
 

 static int vp9_alloc_frame(AVCodecContext *ctx, VP9Frame *f)
 {
     VP9Context *s = ctx->priv_data;
     int ret, sz;
 
     if ((ret = ff_thread_get_buffer(ctx, &f->tf, AV_GET_BUFFER_FLAG_REF)) < 0)
         return ret;
     sz = 64 * s->sb_cols * s->sb_rows;
     if (!(f->extradata = av_buffer_allocz(sz * (1 + sizeof(struct VP9mvrefPair))))) {
         ff_thread_release_buffer(ctx, &f->tf);
         return AVERROR(ENOMEM);
     }
 
     f->segmentation_map = f->extradata->data;
     f->mv = (struct VP9mvrefPair *) (f->extradata->data + sz);
 
     return 0;
 }
 
 static void vp9_unref_frame(AVCodecContext *ctx, VP9Frame *f)
 {
     ff_thread_release_buffer(ctx, &f->tf);
     av_buffer_unref(&f->extradata);

     f->segmentation_map = NULL;

 }
 
 static int vp9_ref_frame(AVCodecContext *ctx, VP9Frame *dst, VP9Frame *src)
 {
     int res;
 
     if ((res = ff_thread_ref_frame(&dst->tf, &src->tf)) < 0) {
         return res;
     } else if (!(dst->extradata = av_buffer_ref(src->extradata))) {
         vp9_unref_frame(ctx, dst);
         return AVERROR(ENOMEM);
     }
 
     dst->segmentation_map = src->segmentation_map;
     dst->mv = src->mv;

     dst->uses_2pass = src->uses_2pass;

 
     return 0;
 }
 

 static int update_size(AVCodecContext *ctx, int w, int h, enum AVPixelFormat fmt)

 {
     VP9Context *s = ctx->priv_data;
     uint8_t *p;

     int bytesperpixel = s->bytesperpixel;

     av_assert0(w > 0 && h > 0);
 

     if (s->intra_pred_data[0] && w == ctx->width && h == ctx->height && ctx->pix_fmt == fmt)

         return 0;
 

     ctx->width   = w;
     ctx->height  = h;
     ctx->pix_fmt = fmt;
     s->sb_cols   = (w + 63) >> 6;
     s->sb_rows   = (h + 63) >> 6;
     s->cols      = (w + 7) >> 3;
     s->rows      = (h + 7) >> 3;

 #define assign(var, type, n) var = (type) p; p += s->sb_cols * (n) * sizeof(*var)

     av_freep(&s->intra_pred_data[0]);

     // FIXME we slightly over-allocate here for subsampled chroma, but a little
     // bit of padding shouldn't affect performance...

     p = av_malloc(s->sb_cols * (128 + 192 * bytesperpixel +
                                 sizeof(*s->lflvl) + 16 * sizeof(*s->above_mv_ctx)));

     if (!p)
         return AVERROR(ENOMEM);

     assign(s->intra_pred_data[0],  uint8_t *,             64 * bytesperpixel);
     assign(s->intra_pred_data[1],  uint8_t *,             64 * bytesperpixel);
     assign(s->intra_pred_data[2],  uint8_t *,             64 * bytesperpixel);

     assign(s->above_y_nnz_ctx,     uint8_t *,             16);
     assign(s->above_mode_ctx,      uint8_t *,             16);
     assign(s->above_mv_ctx,        VP56mv(*)[2],          16);

     assign(s->above_uv_nnz_ctx[0], uint8_t *,             16);
     assign(s->above_uv_nnz_ctx[1], uint8_t *,             16);

     assign(s->above_partition_ctx, uint8_t *,              8);
     assign(s->above_skip_ctx,      uint8_t *,              8);
     assign(s->above_txfm_ctx,      uint8_t *,              8);
     assign(s->above_segpred_ctx,   uint8_t *,              8);
     assign(s->above_intra_ctx,     uint8_t *,              8);
     assign(s->above_comp_ctx,      uint8_t *,              8);
     assign(s->above_ref_ctx,       uint8_t *,              8);
     assign(s->above_filter_ctx,    uint8_t *,              8);
     assign(s->lflvl,               struct VP9Filter *,     1);
 #undef assign
 

     // these will be re-allocated a little later
     av_freep(&s->b_base);
     av_freep(&s->block_base);
 

     if (s->bpp != s->last_bpp) {
         ff_vp9dsp_init(&s->dsp, s->bpp);
         ff_videodsp_init(&s->vdsp, s->bpp);
         s->last_bpp = s->bpp;
     }
 

     return 0;
 }
 
 static int update_block_buffers(AVCodecContext *ctx)
 {
     VP9Context *s = ctx->priv_data;

     int chroma_blocks, chroma_eobs, bytesperpixel = s->bytesperpixel;

     if (s->b_base && s->block_base && s->block_alloc_using_2pass == s->frames[CUR_FRAME].uses_2pass)

         return 0;
 

     av_free(s->b_base);
     av_free(s->block_base);

     chroma_blocks = 64 * 64 >> (s->ss_h + s->ss_v);
     chroma_eobs   = 16 * 16 >> (s->ss_h + s->ss_v);

     if (s->frames[CUR_FRAME].uses_2pass) {

         int sbs = s->sb_cols * s->sb_rows;
 

         s->b_base = av_malloc_array(s->cols * s->rows, sizeof(VP9Block));

         s->block_base = av_mallocz(((64 * 64 + 2 * chroma_blocks) * bytesperpixel * sizeof(int16_t) +

                                     16 * 16 + 2 * chroma_eobs) * sbs);

         if (!s->b_base || !s->block_base)
             return AVERROR(ENOMEM);

         s->uvblock_base[0] = s->block_base + sbs * 64 * 64 * bytesperpixel;
         s->uvblock_base[1] = s->uvblock_base[0] + sbs * chroma_blocks * bytesperpixel;
         s->eob_base = (uint8_t *) (s->uvblock_base[1] + sbs * chroma_blocks * bytesperpixel);

         s->uveob_base[0] = s->eob_base + 16 * 16 * sbs;
         s->uveob_base[1] = s->uveob_base[0] + chroma_eobs * sbs;

     } else {
         s->b_base = av_malloc(sizeof(VP9Block));

         s->block_base = av_mallocz((64 * 64 + 2 * chroma_blocks) * bytesperpixel * sizeof(int16_t) +

                                    16 * 16 + 2 * chroma_eobs);

         if (!s->b_base || !s->block_base)
             return AVERROR(ENOMEM);

         s->uvblock_base[0] = s->block_base + 64 * 64 * bytesperpixel;
         s->uvblock_base[1] = s->uvblock_base[0] + chroma_blocks * bytesperpixel;
         s->eob_base = (uint8_t *) (s->uvblock_base[1] + chroma_blocks * bytesperpixel);

         s->uveob_base[0] = s->eob_base + 16 * 16;
         s->uveob_base[1] = s->uveob_base[0] + chroma_eobs;

     }

     s->block_alloc_using_2pass = s->frames[CUR_FRAME].uses_2pass;

     return 0;
 }
 
 // for some reason the sign bit is at the end, not the start, of a bit sequence
 static av_always_inline int get_sbits_inv(GetBitContext *gb, int n)
 {
     int v = get_bits(gb, n);
     return get_bits1(gb) ? -v : v;
 }
 
 static av_always_inline int inv_recenter_nonneg(int v, int m)
 {
     return v > 2 * m ? v : v & 1 ? m - ((v + 1) >> 1) : m + (v >> 1);
 }
 
 // differential forward probability updates
 static int update_prob(VP56RangeCoder *c, int p)
 {

     static const int inv_map_table[255] = {

           7,  20,  33,  46,  59,  72,  85,  98, 111, 124, 137, 150, 163, 176,
         189, 202, 215, 228, 241, 254,   1,   2,   3,   4,   5,   6,   8,   9,
          10,  11,  12,  13,  14,  15,  16,  17,  18,  19,  21,  22,  23,  24,
          25,  26,  27,  28,  29,  30,  31,  32,  34,  35,  36,  37,  38,  39,
          40,  41,  42,  43,  44,  45,  47,  48,  49,  50,  51,  52,  53,  54,
          55,  56,  57,  58,  60,  61,  62,  63,  64,  65,  66,  67,  68,  69,
          70,  71,  73,  74,  75,  76,  77,  78,  79,  80,  81,  82,  83,  84,
          86,  87,  88,  89,  90,  91,  92,  93,  94,  95,  96,  97,  99, 100,
         101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 112, 113, 114, 115,
         116, 117, 118, 119, 120, 121, 122, 123, 125, 126, 127, 128, 129, 130,
         131, 132, 133, 134, 135, 136, 138, 139, 140, 141, 142, 143, 144, 145,
         146, 147, 148, 149, 151, 152, 153, 154, 155, 156, 157, 158, 159, 160,
         161, 162, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175,
         177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 190, 191,
         192, 193, 194, 195, 196, 197, 198, 199, 200, 201, 203, 204, 205, 206,
         207, 208, 209, 210, 211, 212, 213, 214, 216, 217, 218, 219, 220, 221,
         222, 223, 224, 225, 226, 227, 229, 230, 231, 232, 233, 234, 235, 236,
         237, 238, 239, 240, 242, 243, 244, 245, 246, 247, 248, 249, 250, 251,

         252, 253, 253,

     };
     int d;
 
     /* This code is trying to do a differential probability update. For a
      * current probability A in the range [1, 255], the difference to a new
      * probability of any value can be expressed differentially as 1-A,255-A
      * where some part of this (absolute range) exists both in positive as
      * well as the negative part, whereas another part only exists in one
      * half. We're trying to code this shared part differentially, i.e.
      * times two where the value of the lowest bit specifies the sign, and
      * the single part is then coded on top of this. This absolute difference
      * then again has a value of [0,254], but a bigger value in this range
      * indicates that we're further away from the original value A, so we
      * can code this as a VLC code, since higher values are increasingly
      * unlikely. The first 20 values in inv_map_table[] allow 'cheap, rough'
      * updates vs. the 'fine, exact' updates further down the range, which
      * adds one extra dimension to this differential update model. */
 
     if (!vp8_rac_get(c)) {
         d = vp8_rac_get_uint(c, 4) + 0;
     } else if (!vp8_rac_get(c)) {
         d = vp8_rac_get_uint(c, 4) + 16;
     } else if (!vp8_rac_get(c)) {
         d = vp8_rac_get_uint(c, 5) + 32;
     } else {
         d = vp8_rac_get_uint(c, 7);
         if (d >= 65)
             d = (d << 1) - 65 + vp8_rac_get(c);
         d += 64;

         av_assert2(d < FF_ARRAY_ELEMS(inv_map_table));

     }
 
     return p <= 128 ? 1 + inv_recenter_nonneg(inv_map_table[d], p - 1) :
                     255 - inv_recenter_nonneg(inv_map_table[d], 255 - p);
 }
 

 static enum AVPixelFormat read_colorspace_details(AVCodecContext *ctx)
 {
     static const enum AVColorSpace colorspaces[8] = {
         AVCOL_SPC_UNSPECIFIED, AVCOL_SPC_BT470BG, AVCOL_SPC_BT709, AVCOL_SPC_SMPTE170M,
         AVCOL_SPC_SMPTE240M, AVCOL_SPC_BT2020_NCL, AVCOL_SPC_RESERVED, AVCOL_SPC_RGB,
     };
     VP9Context *s = ctx->priv_data;
     enum AVPixelFormat res;

     int bits = ctx->profile <= 1 ? 0 : 1 + get_bits1(&s->gb); // 0:8, 1:10, 2:12

     s->bpp_index = bits;
     s->bpp = 8 + bits * 2;
     s->bytesperpixel = (7 + s->bpp) >> 3;

     ctx->colorspace = colorspaces[get_bits(&s->gb, 3)];
     if (ctx->colorspace == AVCOL_SPC_RGB) { // RGB = profile 1

         static const enum AVPixelFormat pix_fmt_rgb[3] = {
             AV_PIX_FMT_GBRP, AV_PIX_FMT_GBRP10, AV_PIX_FMT_GBRP12
         };
         if (ctx->profile & 1) {

             s->ss_h = s->ss_v = 0;

             res = pix_fmt_rgb[bits];

             ctx->color_range = AVCOL_RANGE_JPEG;

             if (get_bits1(&s->gb)) {
                 av_log(ctx, AV_LOG_ERROR, "Reserved bit set in RGB\n");
                 return AVERROR_INVALIDDATA;
             }

         } else {

             av_log(ctx, AV_LOG_ERROR, "RGB not supported in profile %d\n",
                    ctx->profile);

             return AVERROR_INVALIDDATA;
         }
     } else {

         static const enum AVPixelFormat pix_fmt_for_ss[3][2 /* v */][2 /* h */] = {
             { { AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV422P },
               { AV_PIX_FMT_YUV440P, AV_PIX_FMT_YUV420P } },
             { { AV_PIX_FMT_YUV444P10, AV_PIX_FMT_YUV422P10 },
               { AV_PIX_FMT_YUV440P10, AV_PIX_FMT_YUV420P10 } },
             { { AV_PIX_FMT_YUV444P12, AV_PIX_FMT_YUV422P12 },
               { AV_PIX_FMT_YUV440P12, AV_PIX_FMT_YUV420P12 } }

         };
         ctx->color_range = get_bits1(&s->gb) ? AVCOL_RANGE_JPEG : AVCOL_RANGE_MPEG;

         if (ctx->profile & 1) {

             s->ss_h = get_bits1(&s->gb);
             s->ss_v = get_bits1(&s->gb);

             if ((res = pix_fmt_for_ss[bits][s->ss_v][s->ss_h]) == AV_PIX_FMT_YUV420P) {
                 av_log(ctx, AV_LOG_ERROR, "YUV 4:2:0 not supported in profile %d\n",
                        ctx->profile);

                 return AVERROR_INVALIDDATA;
             } else if (get_bits1(&s->gb)) {

                 av_log(ctx, AV_LOG_ERROR, "Profile %d color details reserved bit set\n",
                        ctx->profile);

                 return AVERROR_INVALIDDATA;
             }
         } else {
             s->ss_h = s->ss_v = 1;

             res = pix_fmt_for_ss[bits][1][1];

         }
     }
 
     return res;
 }
 

 static int decode_frame_header(AVCodecContext *ctx,
                                const uint8_t *data, int size, int *ref)
 {
     VP9Context *s = ctx->priv_data;
     int c, i, j, k, l, m, n, w, h, max, size2, res, sharp;

     enum AVPixelFormat fmt = ctx->pix_fmt;

     int last_invisible;

     const uint8_t *data2;
 
     /* general header */
     if ((res = init_get_bits8(&s->gb, data, size)) < 0) {

         av_log(ctx, AV_LOG_ERROR, "Failed to initialize bitstream reader\n");

         return res;
     }
     if (get_bits(&s->gb, 2) != 0x2) { // frame marker
         av_log(ctx, AV_LOG_ERROR, "Invalid frame marker\n");
         return AVERROR_INVALIDDATA;
     }

     ctx->profile  = get_bits1(&s->gb);
     ctx->profile |= get_bits1(&s->gb) << 1;

     if (ctx->profile == 3) ctx->profile += get_bits1(&s->gb);
     if (ctx->profile > 3) {

         av_log(ctx, AV_LOG_ERROR, "Profile %d is not yet supported\n", ctx->profile);

         return AVERROR_INVALIDDATA;
     }
     if (get_bits1(&s->gb)) {
         *ref = get_bits(&s->gb, 3);
         return 0;
     }
     s->last_keyframe  = s->keyframe;
     s->keyframe       = !get_bits1(&s->gb);

     last_invisible    = s->invisible;

     s->invisible      = !get_bits1(&s->gb);
     s->errorres       = get_bits1(&s->gb);

     s->use_last_frame_mvs = !s->errorres && !last_invisible;

     if (s->keyframe) {
         if (get_bits_long(&s->gb, 24) != VP9_SYNCCODE) { // synccode
             av_log(ctx, AV_LOG_ERROR, "Invalid sync code\n");
             return AVERROR_INVALIDDATA;
         }

         if ((fmt = read_colorspace_details(ctx)) < 0)
             return fmt;

         // for profile 1, here follows the subsampling bits
         s->refreshrefmask = 0xff;
         w = get_bits(&s->gb, 16) + 1;
         h = get_bits(&s->gb, 16) + 1;
         if (get_bits1(&s->gb)) // display size
             skip_bits(&s->gb, 32);
     } else {
         s->intraonly  = s->invisible ? get_bits1(&s->gb) : 0;
         s->resetctx   = s->errorres ? 0 : get_bits(&s->gb, 2);
         if (s->intraonly) {
             if (get_bits_long(&s->gb, 24) != VP9_SYNCCODE) { // synccode
                 av_log(ctx, AV_LOG_ERROR, "Invalid sync code\n");
                 return AVERROR_INVALIDDATA;
             }

             if (ctx->profile >= 1) {

                 if ((fmt = read_colorspace_details(ctx)) < 0)
                     return fmt;
             } else {
                 s->ss_h = s->ss_v = 1;

                 s->bpp = 8;
                 s->bpp_index = 0;
                 s->bytesperpixel = 1;

                 fmt = AV_PIX_FMT_YUV420P;
                 ctx->colorspace = AVCOL_SPC_BT470BG;
                 ctx->color_range = AVCOL_RANGE_JPEG;
             }

             s->refreshrefmask = get_bits(&s->gb, 8);
             w = get_bits(&s->gb, 16) + 1;
             h = get_bits(&s->gb, 16) + 1;
             if (get_bits1(&s->gb)) // display size
                 skip_bits(&s->gb, 32);
         } else {
             s->refreshrefmask = get_bits(&s->gb, 8);
             s->refidx[0]      = get_bits(&s->gb, 3);

             s->signbias[0]    = get_bits1(&s->gb) && !s->errorres;

             s->refidx[1]      = get_bits(&s->gb, 3);

             s->signbias[1]    = get_bits1(&s->gb) && !s->errorres;

             s->refidx[2]      = get_bits(&s->gb, 3);

             s->signbias[2]    = get_bits1(&s->gb) && !s->errorres;

             if (!s->refs[s->refidx[0]].f->data[0] ||
                 !s->refs[s->refidx[1]].f->data[0] ||
                 !s->refs[s->refidx[2]].f->data[0]) {

                 av_log(ctx, AV_LOG_ERROR, "Not all references are available\n");
                 return AVERROR_INVALIDDATA;
             }
             if (get_bits1(&s->gb)) {

                 w = s->refs[s->refidx[0]].f->width;
                 h = s->refs[s->refidx[0]].f->height;

             } else if (get_bits1(&s->gb)) {

                 w = s->refs[s->refidx[1]].f->width;
                 h = s->refs[s->refidx[1]].f->height;

             } else if (get_bits1(&s->gb)) {

                 w = s->refs[s->refidx[2]].f->width;
                 h = s->refs[s->refidx[2]].f->height;

             } else {
                 w = get_bits(&s->gb, 16) + 1;
                 h = get_bits(&s->gb, 16) + 1;
             }

             // Note that in this code, "CUR_FRAME" is actually before we
             // have formally allocated a frame, and thus actually represents
             // the _last_ frame
             s->use_last_frame_mvs &= s->frames[CUR_FRAME].tf.f->width == w &&
                                      s->frames[CUR_FRAME].tf.f->height == h;

             if (get_bits1(&s->gb)) // display size
                 skip_bits(&s->gb, 32);
             s->highprecisionmvs = get_bits1(&s->gb);
             s->filtermode = get_bits1(&s->gb) ? FILTER_SWITCHABLE :
                                                 get_bits(&s->gb, 2);

             s->allowcompinter = (s->signbias[0] != s->signbias[1] ||

                                  s->signbias[0] != s->signbias[2]);

             if (s->allowcompinter) {
                 if (s->signbias[0] == s->signbias[1]) {
                     s->fixcompref    = 2;
                     s->varcompref[0] = 0;
                     s->varcompref[1] = 1;
                 } else if (s->signbias[0] == s->signbias[2]) {
                     s->fixcompref    = 1;
                     s->varcompref[0] = 0;
                     s->varcompref[1] = 2;
                 } else {
                     s->fixcompref    = 0;
                     s->varcompref[0] = 1;
                     s->varcompref[1] = 2;
                 }
             }

 
             for (i = 0; i < 3; i++) {
                 AVFrame *ref = s->refs[s->refidx[i]].f;
                 int refw = ref->width, refh = ref->height;
 

                 if (ref->format != fmt) {
                     av_log(ctx, AV_LOG_ERROR,
                            "Ref pixfmt (%s) did not match current frame (%s)",
                            av_get_pix_fmt_name(ref->format),
                            av_get_pix_fmt_name(fmt));
                     return AVERROR_INVALIDDATA;
                 } else if (refw == w && refh == h) {

                     s->mvscale[i][0] = s->mvscale[i][1] = 0;
                 } else {
                     if (w * 2 < refw || h * 2 < refh || w > 16 * refw || h > 16 * refh) {
                         av_log(ctx, AV_LOG_ERROR,
                                "Invalid ref frame dimensions %dx%d for frame size %dx%d\n",
                                refw, refh, w, h);
                         return AVERROR_INVALIDDATA;
                     }
                     s->mvscale[i][0] = (refw << 14) / w;
                     s->mvscale[i][1] = (refh << 14) / h;
                     s->mvstep[i][0] = 16 * s->mvscale[i][0] >> 14;
                     s->mvstep[i][1] = 16 * s->mvscale[i][1] >> 14;
                 }
             }

         }
     }
     s->refreshctx   = s->errorres ? 0 : get_bits1(&s->gb);
     s->parallelmode = s->errorres ? 1 : get_bits1(&s->gb);
     s->framectxid   = c = get_bits(&s->gb, 2);
 
     /* loopfilter header data */

     if (s->keyframe || s->errorres || s->intraonly) {
         // reset loopfilter defaults
         s->lf_delta.ref[0] = 1;
         s->lf_delta.ref[1] = 0;
         s->lf_delta.ref[2] = -1;
         s->lf_delta.ref[3] = -1;
         s->lf_delta.mode[0] = 0;
         s->lf_delta.mode[1] = 0;

         memset(s->segmentation.feat, 0, sizeof(s->segmentation.feat));

     }

     s->filter.level = get_bits(&s->gb, 6);
     sharp = get_bits(&s->gb, 3);
     // if sharpness changed, reinit lim/mblim LUTs. if it didn't change, keep
     // the old cache values since they are still valid
     if (s->filter.sharpness != sharp)
         memset(s->filter.lim_lut, 0, sizeof(s->filter.lim_lut));
     s->filter.sharpness = sharp;
     if ((s->lf_delta.enabled = get_bits1(&s->gb))) {
         if (get_bits1(&s->gb)) {
             for (i = 0; i < 4; i++)
                 if (get_bits1(&s->gb))
                     s->lf_delta.ref[i] = get_sbits_inv(&s->gb, 6);
             for (i = 0; i < 2; i++)
                 if (get_bits1(&s->gb))
                     s->lf_delta.mode[i] = get_sbits_inv(&s->gb, 6);
         }
     }
 
     /* quantization header data */
     s->yac_qi      = get_bits(&s->gb, 8);
     s->ydc_qdelta  = get_bits1(&s->gb) ? get_sbits_inv(&s->gb, 4) : 0;
     s->uvdc_qdelta = get_bits1(&s->gb) ? get_sbits_inv(&s->gb, 4) : 0;
     s->uvac_qdelta = get_bits1(&s->gb) ? get_sbits_inv(&s->gb, 4) : 0;
     s->lossless    = s->yac_qi == 0 && s->ydc_qdelta == 0 &&
                      s->uvdc_qdelta == 0 && s->uvac_qdelta == 0;

     if (s->lossless)
         ctx->properties |= FF_CODEC_PROPERTY_LOSSLESS;

 
     /* segmentation header info */

     s->segmentation.ignore_refmap = 0;

     if ((s->segmentation.enabled = get_bits1(&s->gb))) {
         if ((s->segmentation.update_map = get_bits1(&s->gb))) {
             for (i = 0; i < 7; i++)
                 s->prob.seg[i] = get_bits1(&s->gb) ?
                                  get_bits(&s->gb, 8) : 255;

             if ((s->segmentation.temporal = get_bits1(&s->gb))) {

                 for (i = 0; i < 3; i++)
                     s->prob.segpred[i] = get_bits1(&s->gb) ?
                                          get_bits(&s->gb, 8) : 255;

             }
         }
         if ((!s->segmentation.update_map || s->segmentation.temporal) &&
             (w != s->frames[CUR_FRAME].tf.f->width ||
              h != s->frames[CUR_FRAME].tf.f->height)) {

             av_log(ctx, AV_LOG_WARNING,

                    "Reference segmap (temp=%d,update=%d) enabled on size-change!\n",
                    s->segmentation.temporal, s->segmentation.update_map);

             s->segmentation.ignore_refmap = 1;

             //return AVERROR_INVALIDDATA;

         }
 
         if (get_bits1(&s->gb)) {
             s->segmentation.absolute_vals = get_bits1(&s->gb);
             for (i = 0; i < 8; i++) {
                 if ((s->segmentation.feat[i].q_enabled = get_bits1(&s->gb)))
                     s->segmentation.feat[i].q_val = get_sbits_inv(&s->gb, 8);
                 if ((s->segmentation.feat[i].lf_enabled = get_bits1(&s->gb)))
                     s->segmentation.feat[i].lf_val = get_sbits_inv(&s->gb, 6);
                 if ((s->segmentation.feat[i].ref_enabled = get_bits1(&s->gb)))
                     s->segmentation.feat[i].ref_val = get_bits(&s->gb, 2);
                 s->segmentation.feat[i].skip_enabled = get_bits1(&s->gb);
             }
         }
     }
 
     // set qmul[] based on Y/UV, AC/DC and segmentation Q idx deltas
     for (i = 0; i < (s->segmentation.enabled ? 8 : 1); i++) {
         int qyac, qydc, quvac, quvdc, lflvl, sh;
 

         if (s->segmentation.enabled && s->segmentation.feat[i].q_enabled) {

             if (s->segmentation.absolute_vals)

                 qyac = av_clip_uintp2(s->segmentation.feat[i].q_val, 8);

             else

                 qyac = av_clip_uintp2(s->yac_qi + s->segmentation.feat[i].q_val, 8);

         } else {
             qyac  = s->yac_qi;
         }
         qydc  = av_clip_uintp2(qyac + s->ydc_qdelta, 8);
         quvdc = av_clip_uintp2(qyac + s->uvdc_qdelta, 8);
         quvac = av_clip_uintp2(qyac + s->uvac_qdelta, 8);
         qyac  = av_clip_uintp2(qyac, 8);
 

         s->segmentation.feat[i].qmul[0][0] = vp9_dc_qlookup[s->bpp_index][qydc];
         s->segmentation.feat[i].qmul[0][1] = vp9_ac_qlookup[s->bpp_index][qyac];
         s->segmentation.feat[i].qmul[1][0] = vp9_dc_qlookup[s->bpp_index][quvdc];
         s->segmentation.feat[i].qmul[1][1] = vp9_ac_qlookup[s->bpp_index][quvac];

 
         sh = s->filter.level >= 32;

         if (s->segmentation.enabled && s->segmentation.feat[i].lf_enabled) {

             if (s->segmentation.absolute_vals)

                 lflvl = av_clip_uintp2(s->segmentation.feat[i].lf_val, 6);

             else

                 lflvl = av_clip_uintp2(s->filter.level + s->segmentation.feat[i].lf_val, 6);

         } else {
             lflvl  = s->filter.level;
         }

         if (s->lf_delta.enabled) {
             s->segmentation.feat[i].lflvl[0][0] =
             s->segmentation.feat[i].lflvl[0][1] =
                 av_clip_uintp2(lflvl + (s->lf_delta.ref[0] << sh), 6);
             for (j = 1; j < 4; j++) {
                 s->segmentation.feat[i].lflvl[j][0] =
                     av_clip_uintp2(lflvl + ((s->lf_delta.ref[j] +
                                              s->lf_delta.mode[0]) * (1 << sh)), 6);
                 s->segmentation.feat[i].lflvl[j][1] =
                     av_clip_uintp2(lflvl + ((s->lf_delta.ref[j] +
                                              s->lf_delta.mode[1]) * (1 << sh)), 6);
             }
         } else {
             memset(s->segmentation.feat[i].lflvl, lflvl,
                    sizeof(s->segmentation.feat[i].lflvl));

         }
     }
 
     /* tiling info */

     if ((res = update_size(ctx, w, h, fmt)) < 0) {
         av_log(ctx, AV_LOG_ERROR, "Failed to initialize decoder for %dx%d @ %d\n", w, h, fmt);

         return res;
     }
     for (s->tiling.log2_tile_cols = 0;
          (s->sb_cols >> s->tiling.log2_tile_cols) > 64;
          s->tiling.log2_tile_cols++) ;
     for (max = 0; (s->sb_cols >> max) >= 4; max++) ;
     max = FFMAX(0, max - 1);
     while (max > s->tiling.log2_tile_cols) {
         if (get_bits1(&s->gb))
             s->tiling.log2_tile_cols++;
         else
             break;
     }
     s->tiling.log2_tile_rows = decode012(&s->gb);
     s->tiling.tile_rows = 1 << s->tiling.log2_tile_rows;
     if (s->tiling.tile_cols != (1 << s->tiling.log2_tile_cols)) {
         s->tiling.tile_cols = 1 << s->tiling.log2_tile_cols;
         s->c_b = av_fast_realloc(s->c_b, &s->c_b_size,
                                  sizeof(VP56RangeCoder) * s->tiling.tile_cols);
         if (!s->c_b) {
             av_log(ctx, AV_LOG_ERROR, "Ran out of memory during range coder init\n");
             return AVERROR(ENOMEM);
         }
     }
 

     if (s->keyframe || s->errorres || (s->intraonly && s->resetctx == 3)) {

         s->prob_ctx[0].p = s->prob_ctx[1].p = s->prob_ctx[2].p =
                            s->prob_ctx[3].p = vp9_default_probs;
         memcpy(s->prob_ctx[0].coef, vp9_default_coef_probs,
                sizeof(vp9_default_coef_probs));
         memcpy(s->prob_ctx[1].coef, vp9_default_coef_probs,
                sizeof(vp9_default_coef_probs));
         memcpy(s->prob_ctx[2].coef, vp9_default_coef_probs,
                sizeof(vp9_default_coef_probs));
         memcpy(s->prob_ctx[3].coef, vp9_default_coef_probs,
                sizeof(vp9_default_coef_probs));

     } else if (s->intraonly && s->resetctx == 2) {
         s->prob_ctx[c].p = vp9_default_probs;
         memcpy(s->prob_ctx[c].coef, vp9_default_coef_probs,
                sizeof(vp9_default_coef_probs));

     }
 
     // next 16 bits is size of the rest of the header (arith-coded)
     size2 = get_bits(&s->gb, 16);
     data2 = align_get_bits(&s->gb);
     if (size2 > size - (data2 - data)) {
         av_log(ctx, AV_LOG_ERROR, "Invalid compressed header size\n");
         return AVERROR_INVALIDDATA;
     }
     ff_vp56_init_range_decoder(&s->c, data2, size2);
     if (vp56_rac_get_prob_branchy(&s->c, 128)) { // marker bit
         av_log(ctx, AV_LOG_ERROR, "Marker bit was set\n");
         return AVERROR_INVALIDDATA;
     }
 
     if (s->keyframe || s->intraonly) {

         memset(s->counts.coef, 0, sizeof(s->counts.coef));
         memset(s->counts.eob,  0, sizeof(s->counts.eob));

     } else {
         memset(&s->counts, 0, sizeof(s->counts));
     }
     // FIXME is it faster to not copy here, but do it down in the fw updates
     // as explicit copies if the fw update is missing (and skip the copy upon
     // fw update)?
     s->prob.p = s->prob_ctx[c].p;
 
     // txfm updates
     if (s->lossless) {
         s->txfmmode = TX_4X4;
     } else {
         s->txfmmode = vp8_rac_get_uint(&s->c, 2);
         if (s->txfmmode == 3)
             s->txfmmode += vp8_rac_get(&s->c);
 
         if (s->txfmmode == TX_SWITCHABLE) {
             for (i = 0; i < 2; i++)
                 if (vp56_rac_get_prob_branchy(&s->c, 252))
                     s->prob.p.tx8p[i] = update_prob(&s->c, s->prob.p.tx8p[i]);
             for (i = 0; i < 2; i++)
                 for (j = 0; j < 2; j++)
                     if (vp56_rac_get_prob_branchy(&s->c, 252))
                         s->prob.p.tx16p[i][j] =
                             update_prob(&s->c, s->prob.p.tx16p[i][j]);
             for (i = 0; i < 2; i++)
                 for (j = 0; j < 3; j++)
                     if (vp56_rac_get_prob_branchy(&s->c, 252))
                         s->prob.p.tx32p[i][j] =
                             update_prob(&s->c, s->prob.p.tx32p[i][j]);
         }
     }
 
     // coef updates
     for (i = 0; i < 4; i++) {
         uint8_t (*ref)[2][6][6][3] = s->prob_ctx[c].coef[i];
         if (vp8_rac_get(&s->c)) {
             for (j = 0; j < 2; j++)
                 for (k = 0; k < 2; k++)
                     for (l = 0; l < 6; l++)
                         for (m = 0; m < 6; m++) {
                             uint8_t *p = s->prob.coef[i][j][k][l][m];
                             uint8_t *r = ref[j][k][l][m];
                             if (m >= 3 && l == 0) // dc only has 3 pt
                                 break;
                             for (n = 0; n < 3; n++) {
                                 if (vp56_rac_get_prob_branchy(&s->c, 252)) {
                                     p[n] = update_prob(&s->c, r[n]);
                                 } else {
                                     p[n] = r[n];
                                 }
                             }
                             p[3] = 0;
                         }
         } else {
             for (j = 0; j < 2; j++)
                 for (k = 0; k < 2; k++)
                     for (l = 0; l < 6; l++)
                         for (m = 0; m < 6; m++) {
                             uint8_t *p = s->prob.coef[i][j][k][l][m];
                             uint8_t *r = ref[j][k][l][m];
                             if (m > 3 && l == 0) // dc only has 3 pt
                                 break;
                             memcpy(p, r, 3);
                             p[3] = 0;
                         }
         }
         if (s->txfmmode == i)
             break;
     }
 
     // mode updates
     for (i = 0; i < 3; i++)
         if (vp56_rac_get_prob_branchy(&s->c, 252))
             s->prob.p.skip[i] = update_prob(&s->c, s->prob.p.skip[i]);
     if (!s->keyframe && !s->intraonly) {
         for (i = 0; i < 7; i++)
             for (j = 0; j < 3; j++)
                 if (vp56_rac_get_prob_branchy(&s->c, 252))
                     s->prob.p.mv_mode[i][j] =
                         update_prob(&s->c, s->prob.p.mv_mode[i][j]);
 
         if (s->filtermode == FILTER_SWITCHABLE)
             for (i = 0; i < 4; i++)
                 for (j = 0; j < 2; j++)
                     if (vp56_rac_get_prob_branchy(&s->c, 252))
                         s->prob.p.filter[i][j] =
                             update_prob(&s->c, s->prob.p.filter[i][j]);
 
         for (i = 0; i < 4; i++)
             if (vp56_rac_get_prob_branchy(&s->c, 252))
                 s->prob.p.intra[i] = update_prob(&s->c, s->prob.p.intra[i]);
 
         if (s->allowcompinter) {
             s->comppredmode = vp8_rac_get(&s->c);
             if (s->comppredmode)
                 s->comppredmode += vp8_rac_get(&s->c);
             if (s->comppredmode == PRED_SWITCHABLE)
                 for (i = 0; i < 5; i++)
                     if (vp56_rac_get_prob_branchy(&s->c, 252))
                         s->prob.p.comp[i] =
                             update_prob(&s->c, s->prob.p.comp[i]);
         } else {
             s->comppredmode = PRED_SINGLEREF;
         }
 
         if (s->comppredmode != PRED_COMPREF) {
             for (i = 0; i < 5; i++) {
                 if (vp56_rac_get_prob_branchy(&s->c, 252))
                     s->prob.p.single_ref[i][0] =
                         update_prob(&s->c, s->prob.p.single_ref[i][0]);
                 if (vp56_rac_get_prob_branchy(&s->c, 252))
                     s->prob.p.single_ref[i][1] =
                         update_prob(&s->c, s->prob.p.single_ref[i][1]);
             }
         }
 
         if (s->comppredmode != PRED_SINGLEREF) {
             for (i = 0; i < 5; i++)
                 if (vp56_rac_get_prob_branchy(&s->c, 252))
                     s->prob.p.comp_ref[i] =
                         update_prob(&s->c, s->prob.p.comp_ref[i]);
         }
 
         for (i = 0; i < 4; i++)
             for (j = 0; j < 9; j++)
                 if (vp56_rac_get_prob_branchy(&s->c, 252))
                     s->prob.p.y_mode[i][j] =
                         update_prob(&s->c, s->prob.p.y_mode[i][j]);
 
         for (i = 0; i < 4; i++)
             for (j = 0; j < 4; j++)
                 for (k = 0; k < 3; k++)
                     if (vp56_rac_get_prob_branchy(&s->c, 252))
                         s->prob.p.partition[3 - i][j][k] =
                             update_prob(&s->c, s->prob.p.partition[3 - i][j][k]);
 
         // mv fields don't use the update_prob subexp model for some reason
         for (i = 0; i < 3; i++)
             if (vp56_rac_get_prob_branchy(&s->c, 252))
                 s->prob.p.mv_joint[i] = (vp8_rac_get_uint(&s->c, 7) << 1) | 1;
 
         for (i = 0; i < 2; i++) {
             if (vp56_rac_get_prob_branchy(&s->c, 252))
                 s->prob.p.mv_comp[i].sign = (vp8_rac_get_uint(&s->c, 7) << 1) | 1;
 
             for (j = 0; j < 10; j++)
                 if (vp56_rac_get_prob_branchy(&s->c, 252))
                     s->prob.p.mv_comp[i].classes[j] =
                         (vp8_rac_get_uint(&s->c, 7) << 1) | 1;
 
             if (vp56_rac_get_prob_branchy(&s->c, 252))
                 s->prob.p.mv_comp[i].class0 = (vp8_rac_get_uint(&s->c, 7) << 1) | 1;
 
             for (j = 0; j < 10; j++)
                 if (vp56_rac_get_prob_branchy(&s->c, 252))
                     s->prob.p.mv_comp[i].bits[j] =
                         (vp8_rac_get_uint(&s->c, 7) << 1) | 1;
         }
 
         for (i = 0; i < 2; i++) {
             for (j = 0; j < 2; j++)
                 for (k = 0; k < 3; k++)
                     if (vp56_rac_get_prob_branchy(&s->c, 252))
                         s->prob.p.mv_comp[i].class0_fp[j][k] =
                             (vp8_rac_get_uint(&s->c, 7) << 1) | 1;
 
             for (j = 0; j < 3; j++)
                 if (vp56_rac_get_prob_branchy(&s->c, 252))
                     s->prob.p.mv_comp[i].fp[j] =
                         (vp8_rac_get_uint(&s->c, 7) << 1) | 1;
         }
 
         if (s->highprecisionmvs) {
             for (i = 0; i < 2; i++) {
                 if (vp56_rac_get_prob_branchy(&s->c, 252))
                     s->prob.p.mv_comp[i].class0_hp =
                         (vp8_rac_get_uint(&s->c, 7) << 1) | 1;
 
                 if (vp56_rac_get_prob_branchy(&s->c, 252))
                     s->prob.p.mv_comp[i].hp =
                         (vp8_rac_get_uint(&s->c, 7) << 1) | 1;
             }
         }
     }
 
     return (data2 - data) + size2;
 }
 
 static av_always_inline void clamp_mv(VP56mv *dst, const VP56mv *src,
                                       VP9Context *s)
 {
     dst->x = av_clip(src->x, s->min_mv.x, s->max_mv.x);
     dst->y = av_clip(src->y, s->min_mv.y, s->max_mv.y);
 }
 
 static void find_ref_mvs(VP9Context *s,
                          VP56mv *pmv, int ref, int z, int idx, int sb)
 {
     static const int8_t mv_ref_blk_off[N_BS_SIZES][8][2] = {
         [BS_64x64] = {{  3, -1 }, { -1,  3 }, {  4, -1 }, { -1,  4 },
                       { -1, -1 }, {  0, -1 }, { -1,  0 }, {  6, -1 }},
         [BS_64x32] = {{  0, -1 }, { -1,  0 }, {  4, -1 }, { -1,  2 },
                       { -1, -1 }, {  0, -3 }, { -3,  0 }, {  2, -1 }},
         [BS_32x64] = {{ -1,  0 }, {  0, -1 }, { -1,  4 }, {  2, -1 },
                       { -1, -1 }, { -3,  0 }, {  0, -3 }, { -1,  2 }},
         [BS_32x32] = {{  1, -1 }, { -1,  1 }, {  2, -1 }, { -1,  2 },
                       { -1, -1 }, {  0, -3 }, { -3,  0 }, { -3, -3 }},
         [BS_32x16] = {{  0, -1 }, { -1,  0 }, {  2, -1 }, { -1, -1 },
                       { -1,  1 }, {  0, -3 }, { -3,  0 }, { -3, -3 }},
         [BS_16x32] = {{ -1,  0 }, {  0, -1 }, { -1,  2 }, { -1, -1 },
                       {  1, -1 }, { -3,  0 }, {  0, -3 }, { -3, -3 }},
         [BS_16x16] = {{  0, -1 }, { -1,  0 }, {  1, -1 }, { -1,  1 },
                       { -1, -1 }, {  0, -3 }, { -3,  0 }, { -3, -3 }},
         [BS_16x8]  = {{  0, -1 }, { -1,  0 }, {  1, -1 }, { -1, -1 },
                       {  0, -2 }, { -2,  0 }, { -2, -1 }, { -1, -2 }},
         [BS_8x16]  = {{ -1,  0 }, {  0, -1 }, { -1,  1 }, { -1, -1 },
                       { -2,  0 }, {  0, -2 }, { -1, -2 }, { -2, -1 }},
         [BS_8x8]   = {{  0, -1 }, { -1,  0 }, { -1, -1 }, {  0, -2 },
                       { -2,  0 }, { -1, -2 }, { -2, -1 }, { -2, -2 }},
         [BS_8x4]   = {{  0, -1 }, { -1,  0 }, { -1, -1 }, {  0, -2 },
                       { -2,  0 }, { -1, -2 }, { -2, -1 }, { -2, -2 }},
         [BS_4x8]   = {{  0, -1 }, { -1,  0 }, { -1, -1 }, {  0, -2 },
                       { -2,  0 }, { -1, -2 }, { -2, -1 }, { -2, -2 }},
         [BS_4x4]   = {{  0, -1 }, { -1,  0 }, { -1, -1 }, {  0, -2 },
                       { -2,  0 }, { -1, -2 }, { -2, -1 }, { -2, -2 }},
     };

     VP9Block *b = s->b;

     int row = s->row, col = s->col, row7 = s->row7;

     const int8_t (*p)[2] = mv_ref_blk_off[b->bs];
 #define INVALID_MV 0x80008000U

     uint32_t mem = INVALID_MV, mem_sub8x8 = INVALID_MV;

     int i;
 
 #define RETURN_DIRECT_MV(mv) \
     do { \
         uint32_t m = AV_RN32A(&mv); \
         if (!idx) { \
             AV_WN32A(pmv, m); \
             return; \
         } else if (mem == INVALID_MV) { \
             mem = m; \
         } else if (m != mem) { \
             AV_WN32A(pmv, m); \
             return; \
         } \
     } while (0)
 
     if (sb >= 0) {
         if (sb == 2 || sb == 1) {
             RETURN_DIRECT_MV(b->mv[0][z]);
         } else if (sb == 3) {
             RETURN_DIRECT_MV(b->mv[2][z]);
             RETURN_DIRECT_MV(b->mv[1][z]);
             RETURN_DIRECT_MV(b->mv[0][z]);
         }
 
 #define RETURN_MV(mv) \
     do { \
         if (sb > 0) { \
             VP56mv tmp; \
             uint32_t m; \

             av_assert2(idx == 1); \
             av_assert2(mem != INVALID_MV); \
             if (mem_sub8x8 == INVALID_MV) { \
                 clamp_mv(&tmp, &mv, s); \
                 m = AV_RN32A(&tmp); \
                 if (m != mem) { \
                     AV_WN32A(pmv, m); \
                     return; \
                 } \
                 mem_sub8x8 = AV_RN32A(&mv); \
             } else if (mem_sub8x8 != AV_RN32A(&mv)) { \
                 clamp_mv(&tmp, &mv, s); \
                 m = AV_RN32A(&tmp); \
                 if (m != mem) { \
                     AV_WN32A(pmv, m); \
                 } else { \
                     /* BUG I'm pretty sure this isn't the intention */ \
                     AV_WN32A(pmv, 0); \
                 } \

                 return; \
             } \
         } else { \
             uint32_t m = AV_RN32A(&mv); \
             if (!idx) { \
                 clamp_mv(pmv, &mv, s); \
                 return; \
             } else if (mem == INVALID_MV) { \
                 mem = m; \
             } else if (m != mem) { \
                 clamp_mv(pmv, &mv, s); \
                 return; \
             } \
         } \
     } while (0)
 
         if (row > 0) {

             struct VP9mvrefPair *mv = &s->frames[CUR_FRAME].mv[(row - 1) * s->sb_cols * 8 + col];

             if (mv->ref[0] == ref) {
                 RETURN_MV(s->above_mv_ctx[2 * col + (sb & 1)][0]);
             } else if (mv->ref[1] == ref) {
                 RETURN_MV(s->above_mv_ctx[2 * col + (sb & 1)][1]);
             }
         }
         if (col > s->tiling.tile_col_start) {

             struct VP9mvrefPair *mv = &s->frames[CUR_FRAME].mv[row * s->sb_cols * 8 + col - 1];

             if (mv->ref[0] == ref) {
                 RETURN_MV(s->left_mv_ctx[2 * row7 + (sb >> 1)][0]);
             } else if (mv->ref[1] == ref) {
                 RETURN_MV(s->left_mv_ctx[2 * row7 + (sb >> 1)][1]);
             }
         }
         i = 2;
     } else {
         i = 0;
     }
 
     // previously coded MVs in this neighbourhood, using same reference frame
     for (; i < 8; i++) {
         int c = p[i][0] + col, r = p[i][1] + row;
 
         if (c >= s->tiling.tile_col_start && c < s->cols && r >= 0 && r < s->rows) {

             struct VP9mvrefPair *mv = &s->frames[CUR_FRAME].mv[r * s->sb_cols * 8 + c];

 
             if (mv->ref[0] == ref) {
                 RETURN_MV(mv->mv[0]);
             } else if (mv->ref[1] == ref) {
                 RETURN_MV(mv->mv[1]);
             }
         }
     }
 
     // MV at this position in previous frame, using same reference frame
     if (s->use_last_frame_mvs) {

         struct VP9mvrefPair *mv = &s->frames[REF_FRAME_MVPAIR].mv[row * s->sb_cols * 8 + col];

         if (!s->frames[REF_FRAME_MVPAIR].uses_2pass)
             ff_thread_await_progress(&s->frames[REF_FRAME_MVPAIR].tf, row >> 3, 0);

         if (mv->ref[0] == ref) {
             RETURN_MV(mv->mv[0]);
         } else if (mv->ref[1] == ref) {
             RETURN_MV(mv->mv[1]);
         }
     }
 
 #define RETURN_SCALE_MV(mv, scale) \
     do { \
         if (scale) { \
             VP56mv mv_temp = { -mv.x, -mv.y }; \
             RETURN_MV(mv_temp); \
         } else { \
             RETURN_MV(mv); \
         } \
     } while (0)
 
     // previously coded MVs in this neighbourhood, using different reference frame
     for (i = 0; i < 8; i++) {
         int c = p[i][0] + col, r = p[i][1] + row;
 
         if (c >= s->tiling.tile_col_start && c < s->cols && r >= 0 && r < s->rows) {

             struct VP9mvrefPair *mv = &s->frames[CUR_FRAME].mv[r * s->sb_cols * 8 + c];

 
             if (mv->ref[0] != ref && mv->ref[0] >= 0) {
                 RETURN_SCALE_MV(mv->mv[0], s->signbias[mv->ref[0]] != s->signbias[ref]);
             }

             if (mv->ref[1] != ref && mv->ref[1] >= 0 &&
                 // BUG - libvpx has this condition regardless of whether
                 // we used the first ref MV and pre-scaling
                 AV_RN32A(&mv->mv[0]) != AV_RN32A(&mv->mv[1])) {

                 RETURN_SCALE_MV(mv->mv[1], s->signbias[mv->ref[1]] != s->signbias[ref]);
             }
         }
     }
 
     // MV at this position in previous frame, using different reference frame
     if (s->use_last_frame_mvs) {

         struct VP9mvrefPair *mv = &s->frames[REF_FRAME_MVPAIR].mv[row * s->sb_cols * 8 + col];

         // no need to await_progress, because we already did that above

         if (mv->ref[0] != ref && mv->ref[0] >= 0) {
             RETURN_SCALE_MV(mv->mv[0], s->signbias[mv->ref[0]] != s->signbias[ref]);
         }

         if (mv->ref[1] != ref && mv->ref[1] >= 0 &&
             // BUG - libvpx has this condition regardless of whether
             // we used the first ref MV and pre-scaling
             AV_RN32A(&mv->mv[0]) != AV_RN32A(&mv->mv[1])) {

             RETURN_SCALE_MV(mv->mv[1], s->signbias[mv->ref[1]] != s->signbias[ref]);
         }
     }
 
     AV_ZERO32(pmv);

     clamp_mv(pmv, pmv, s);

 #undef INVALID_MV
 #undef RETURN_MV
 #undef RETURN_SCALE_MV
 }
 
 static av_always_inline int read_mv_component(VP9Context *s, int idx, int hp)
 {
     int bit, sign = vp56_rac_get_prob(&s->c, s->prob.p.mv_comp[idx].sign);
     int n, c = vp8_rac_get_tree(&s->c, vp9_mv_class_tree,
                                 s->prob.p.mv_comp[idx].classes);
 
     s->counts.mv_comp[idx].sign[sign]++;
     s->counts.mv_comp[idx].classes[c]++;
     if (c) {
         int m;
 
         for (n = 0, m = 0; m < c; m++) {
             bit = vp56_rac_get_prob(&s->c, s->prob.p.mv_comp[idx].bits[m]);
             n |= bit << m;
             s->counts.mv_comp[idx].bits[m][bit]++;
         }
         n <<= 3;
         bit = vp8_rac_get_tree(&s->c, vp9_mv_fp_tree, s->prob.p.mv_comp[idx].fp);
         n |= bit << 1;
         s->counts.mv_comp[idx].fp[bit]++;
         if (hp) {
             bit = vp56_rac_get_prob(&s->c, s->prob.p.mv_comp[idx].hp);
             s->counts.mv_comp[idx].hp[bit]++;
             n |= bit;
         } else {
             n |= 1;
             // bug in libvpx - we count for bw entropy purposes even if the
             // bit wasn't coded
             s->counts.mv_comp[idx].hp[1]++;
         }
         n += 8 << c;
     } else {
         n = vp56_rac_get_prob(&s->c, s->prob.p.mv_comp[idx].class0);
         s->counts.mv_comp[idx].class0[n]++;
         bit = vp8_rac_get_tree(&s->c, vp9_mv_fp_tree,
                                s->prob.p.mv_comp[idx].class0_fp[n]);
         s->counts.mv_comp[idx].class0_fp[n][bit]++;
         n = (n << 3) | (bit << 1);
         if (hp) {
             bit = vp56_rac_get_prob(&s->c, s->prob.p.mv_comp[idx].class0_hp);
             s->counts.mv_comp[idx].class0_hp[bit]++;
             n |= bit;
         } else {
             n |= 1;
             // bug in libvpx - we count for bw entropy purposes even if the
             // bit wasn't coded
             s->counts.mv_comp[idx].class0_hp[1]++;
         }
     }
 
     return sign ? -(n + 1) : (n + 1);
 }
 
 static void fill_mv(VP9Context *s,
                     VP56mv *mv, int mode, int sb)
 {

     VP9Block *b = s->b;

 
     if (mode == ZEROMV) {

         AV_ZERO64(mv);

     } else {
         int hp;
 
         // FIXME cache this value and reuse for other subblocks
         find_ref_mvs(s, &mv[0], b->ref[0], 0, mode == NEARMV,
                      mode == NEWMV ? -1 : sb);
         // FIXME maybe move this code into find_ref_mvs()
         if ((mode == NEWMV || sb == -1) &&
             !(hp = s->highprecisionmvs && abs(mv[0].x) < 64 && abs(mv[0].y) < 64)) {
             if (mv[0].y & 1) {
                 if (mv[0].y < 0)
                     mv[0].y++;
                 else
                     mv[0].y--;
             }
             if (mv[0].x & 1) {
                 if (mv[0].x < 0)
                     mv[0].x++;
                 else
                     mv[0].x--;
             }
         }
         if (mode == NEWMV) {
             enum MVJoint j = vp8_rac_get_tree(&s->c, vp9_mv_joint_tree,
                                               s->prob.p.mv_joint);
 
             s->counts.mv_joint[j]++;
             if (j >= MV_JOINT_V)
                 mv[0].y += read_mv_component(s, 0, hp);
             if (j & 1)
                 mv[0].x += read_mv_component(s, 1, hp);
         }
 
         if (b->comp) {
             // FIXME cache this value and reuse for other subblocks
             find_ref_mvs(s, &mv[1], b->ref[1], 1, mode == NEARMV,
                          mode == NEWMV ? -1 : sb);
             if ((mode == NEWMV || sb == -1) &&
                 !(hp = s->highprecisionmvs && abs(mv[1].x) < 64 && abs(mv[1].y) < 64)) {
                 if (mv[1].y & 1) {
                     if (mv[1].y < 0)
                         mv[1].y++;
                     else
                         mv[1].y--;
                 }
                 if (mv[1].x & 1) {
                     if (mv[1].x < 0)
                         mv[1].x++;
                     else
                         mv[1].x--;
                 }
             }
             if (mode == NEWMV) {
                 enum MVJoint j = vp8_rac_get_tree(&s->c, vp9_mv_joint_tree,
                                                   s->prob.p.mv_joint);
 
                 s->counts.mv_joint[j]++;
                 if (j >= MV_JOINT_V)
                     mv[1].y += read_mv_component(s, 0, hp);
                 if (j & 1)
                     mv[1].x += read_mv_component(s, 1, hp);
             }
         }
     }
 }
 

 static av_always_inline void setctx_2d(uint8_t *ptr, int w, int h,
                                        ptrdiff_t stride, int v)
 {
     switch (w) {
     case 1:
         do {
             *ptr = v;
             ptr += stride;
         } while (--h);
         break;
     case 2: {
         int v16 = v * 0x0101;
         do {
             AV_WN16A(ptr, v16);
             ptr += stride;
         } while (--h);
         break;
     }
     case 4: {
         uint32_t v32 = v * 0x01010101;
         do {
             AV_WN32A(ptr, v32);
             ptr += stride;
         } while (--h);
         break;
     }
     case 8: {
 #if HAVE_FAST_64BIT
         uint64_t v64 = v * 0x0101010101010101ULL;
         do {
             AV_WN64A(ptr, v64);
             ptr += stride;
         } while (--h);
 #else

         uint32_t v32 = v * 0x01010101;

         do {
             AV_WN32A(ptr,     v32);
             AV_WN32A(ptr + 4, v32);
             ptr += stride;
         } while (--h);
 #endif
         break;
     }
     }
 }
 

 static void decode_mode(AVCodecContext *ctx)
 {
     static const uint8_t left_ctx[N_BS_SIZES] = {
         0x0, 0x8, 0x0, 0x8, 0xc, 0x8, 0xc, 0xe, 0xc, 0xe, 0xf, 0xe, 0xf
     };
     static const uint8_t above_ctx[N_BS_SIZES] = {
         0x0, 0x0, 0x8, 0x8, 0x8, 0xc, 0xc, 0xc, 0xe, 0xe, 0xe, 0xf, 0xf
     };
     static const uint8_t max_tx_for_bl_bp[N_BS_SIZES] = {
         TX_32X32, TX_32X32, TX_32X32, TX_32X32, TX_16X16, TX_16X16,
         TX_16X16, TX_8X8, TX_8X8, TX_8X8, TX_4X4, TX_4X4, TX_4X4
     };
     VP9Context *s = ctx->priv_data;

     VP9Block *b = s->b;

     int row = s->row, col = s->col, row7 = s->row7;

     enum TxfmMode max_tx = max_tx_for_bl_bp[b->bs];

     int bw4 = bwh_tab[1][b->bs][0], w4 = FFMIN(s->cols - col, bw4);
     int bh4 = bwh_tab[1][b->bs][1], h4 = FFMIN(s->rows - row, bh4), y;

     int have_a = row > 0, have_l = col > s->tiling.tile_col_start;

     int vref, filter_id;

     if (!s->segmentation.enabled) {

         b->seg_id = 0;
     } else if (s->keyframe || s->intraonly) {

         b->seg_id = !s->segmentation.update_map ? 0 :
                     vp8_rac_get_tree(&s->c, vp9_segmentation_tree, s->prob.seg);

     } else if (!s->segmentation.update_map ||
                (s->segmentation.temporal &&
                 vp56_rac_get_prob_branchy(&s->c,
                     s->prob.segpred[s->above_segpred_ctx[col] +
                                     s->left_segpred_ctx[row7]]))) {

         if (!s->errorres && !s->segmentation.ignore_refmap) {

             int pred = 8, x;

             uint8_t *refsegmap = s->frames[REF_FRAME_SEGMAP].segmentation_map;

             if (!s->frames[REF_FRAME_SEGMAP].uses_2pass)
                 ff_thread_await_progress(&s->frames[REF_FRAME_SEGMAP].tf, row >> 3, 0);

             for (y = 0; y < h4; y++) {
                 int idx_base = (y + row) * 8 * s->sb_cols + col;

                 for (x = 0; x < w4; x++)

                     pred = FFMIN(pred, refsegmap[idx_base + x]);
             }

             av_assert1(pred < 8);
             b->seg_id = pred;
         } else {
             b->seg_id = 0;
         }

 
         memset(&s->above_segpred_ctx[col], 1, w4);
         memset(&s->left_segpred_ctx[row7], 1, h4);
     } else {
         b->seg_id = vp8_rac_get_tree(&s->c, vp9_segmentation_tree,
                                      s->prob.seg);
 
         memset(&s->above_segpred_ctx[col], 0, w4);
         memset(&s->left_segpred_ctx[row7], 0, h4);
     }

     if (s->segmentation.enabled &&
         (s->segmentation.update_map || s->keyframe || s->intraonly)) {

         setctx_2d(&s->frames[CUR_FRAME].segmentation_map[row * 8 * s->sb_cols + col],

                   bw4, bh4, 8 * s->sb_cols, b->seg_id);

     }
 
     b->skip = s->segmentation.enabled &&
         s->segmentation.feat[b->seg_id].skip_enabled;
     if (!b->skip) {
         int c = s->left_skip_ctx[row7] + s->above_skip_ctx[col];
         b->skip = vp56_rac_get_prob(&s->c, s->prob.p.skip[c]);
         s->counts.skip[c][b->skip]++;
     }
 
     if (s->keyframe || s->intraonly) {
         b->intra = 1;

     } else if (s->segmentation.enabled && s->segmentation.feat[b->seg_id].ref_enabled) {

         b->intra = !s->segmentation.feat[b->seg_id].ref_val;
     } else {
         int c, bit;
 
         if (have_a && have_l) {
             c = s->above_intra_ctx[col] + s->left_intra_ctx[row7];
             c += (c == 2);
         } else {
             c = have_a ? 2 * s->above_intra_ctx[col] :
                 have_l ? 2 * s->left_intra_ctx[row7] : 0;
         }
         bit = vp56_rac_get_prob(&s->c, s->prob.p.intra[c]);
         s->counts.intra[c][bit]++;
         b->intra = !bit;
     }
 
     if ((b->intra || !b->skip) && s->txfmmode == TX_SWITCHABLE) {
         int c;
         if (have_a) {
             if (have_l) {
                 c = (s->above_skip_ctx[col] ? max_tx :
                      s->above_txfm_ctx[col]) +
                     (s->left_skip_ctx[row7] ? max_tx :
                      s->left_txfm_ctx[row7]) > max_tx;
             } else {
                 c = s->above_skip_ctx[col] ? 1 :
                     (s->above_txfm_ctx[col] * 2 > max_tx);
             }
         } else if (have_l) {
             c = s->left_skip_ctx[row7] ? 1 :
                 (s->left_txfm_ctx[row7] * 2 > max_tx);
         } else {
             c = 1;
         }
         switch (max_tx) {
         case TX_32X32:
             b->tx = vp56_rac_get_prob(&s->c, s->prob.p.tx32p[c][0]);
             if (b->tx) {
                 b->tx += vp56_rac_get_prob(&s->c, s->prob.p.tx32p[c][1]);
                 if (b->tx == 2)
                     b->tx += vp56_rac_get_prob(&s->c, s->prob.p.tx32p[c][2]);
             }
             s->counts.tx32p[c][b->tx]++;
             break;
         case TX_16X16:
             b->tx = vp56_rac_get_prob(&s->c, s->prob.p.tx16p[c][0]);
             if (b->tx)
                 b->tx += vp56_rac_get_prob(&s->c, s->prob.p.tx16p[c][1]);
             s->counts.tx16p[c][b->tx]++;
             break;
         case TX_8X8:
             b->tx = vp56_rac_get_prob(&s->c, s->prob.p.tx8p[c]);
             s->counts.tx8p[c][b->tx]++;
             break;
         case TX_4X4:
             b->tx = TX_4X4;
             break;
         }
     } else {
         b->tx = FFMIN(max_tx, s->txfmmode);
     }
 
     if (s->keyframe || s->intraonly) {
         uint8_t *a = &s->above_mode_ctx[col * 2];
         uint8_t *l = &s->left_mode_ctx[(row7) << 1];
 
         b->comp = 0;
         if (b->bs > BS_8x8) {
             // FIXME the memory storage intermediates here aren't really
             // necessary, they're just there to make the code slightly
             // simpler for now
             b->mode[0] = a[0] = vp8_rac_get_tree(&s->c, vp9_intramode_tree,
                                     vp9_default_kf_ymode_probs[a[0]][l[0]]);
             if (b->bs != BS_8x4) {
                 b->mode[1] = vp8_rac_get_tree(&s->c, vp9_intramode_tree,
                                  vp9_default_kf_ymode_probs[a[1]][b->mode[0]]);
                 l[0] = a[1] = b->mode[1];
             } else {
                 l[0] = a[1] = b->mode[1] = b->mode[0];
             }
             if (b->bs != BS_4x8) {
                 b->mode[2] = a[0] = vp8_rac_get_tree(&s->c, vp9_intramode_tree,
                                         vp9_default_kf_ymode_probs[a[0]][l[1]]);
                 if (b->bs != BS_8x4) {
                     b->mode[3] = vp8_rac_get_tree(&s->c, vp9_intramode_tree,
                                   vp9_default_kf_ymode_probs[a[1]][b->mode[2]]);
                     l[1] = a[1] = b->mode[3];
                 } else {
                     l[1] = a[1] = b->mode[3] = b->mode[2];
                 }
             } else {
                 b->mode[2] = b->mode[0];
                 l[1] = a[1] = b->mode[3] = b->mode[1];
             }
         } else {
             b->mode[0] = vp8_rac_get_tree(&s->c, vp9_intramode_tree,
                                           vp9_default_kf_ymode_probs[*a][*l]);
             b->mode[3] = b->mode[2] = b->mode[1] = b->mode[0];
             // FIXME this can probably be optimized
             memset(a, b->mode[0], bwh_tab[0][b->bs][0]);
             memset(l, b->mode[0], bwh_tab[0][b->bs][1]);
         }
         b->uvmode = vp8_rac_get_tree(&s->c, vp9_intramode_tree,
                                      vp9_default_kf_uvmode_probs[b->mode[3]]);
     } else if (b->intra) {
         b->comp = 0;
         if (b->bs > BS_8x8) {
             b->mode[0] = vp8_rac_get_tree(&s->c, vp9_intramode_tree,
                                           s->prob.p.y_mode[0]);
             s->counts.y_mode[0][b->mode[0]]++;
             if (b->bs != BS_8x4) {
                 b->mode[1] = vp8_rac_get_tree(&s->c, vp9_intramode_tree,
                                               s->prob.p.y_mode[0]);
                 s->counts.y_mode[0][b->mode[1]]++;
             } else {
                 b->mode[1] = b->mode[0];
             }
             if (b->bs != BS_4x8) {
                 b->mode[2] = vp8_rac_get_tree(&s->c, vp9_intramode_tree,
                                               s->prob.p.y_mode[0]);
                 s->counts.y_mode[0][b->mode[2]]++;
                 if (b->bs != BS_8x4) {
                     b->mode[3] = vp8_rac_get_tree(&s->c, vp9_intramode_tree,
                                                   s->prob.p.y_mode[0]);
                     s->counts.y_mode[0][b->mode[3]]++;
                 } else {
                     b->mode[3] = b->mode[2];
                 }
             } else {
                 b->mode[2] = b->mode[0];
                 b->mode[3] = b->mode[1];
             }
         } else {
             static const uint8_t size_group[10] = {
                 3, 3, 3, 3, 2, 2, 2, 1, 1, 1
             };
             int sz = size_group[b->bs];
 
             b->mode[0] = vp8_rac_get_tree(&s->c, vp9_intramode_tree,
                                           s->prob.p.y_mode[sz]);
             b->mode[1] = b->mode[2] = b->mode[3] = b->mode[0];
             s->counts.y_mode[sz][b->mode[3]]++;
         }
         b->uvmode = vp8_rac_get_tree(&s->c, vp9_intramode_tree,
                                      s->prob.p.uv_mode[b->mode[3]]);
         s->counts.uv_mode[b->mode[3]][b->uvmode]++;
     } else {
         static const uint8_t inter_mode_ctx_lut[14][14] = {
             { 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 5, 5, 5, 5 },
             { 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 5, 5, 5, 5 },
             { 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 5, 5, 5, 5 },
             { 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 5, 5, 5, 5 },
             { 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 5, 5, 5, 5 },
             { 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 5, 5, 5, 5 },
             { 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 5, 5, 5, 5 },
             { 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 5, 5, 5, 5 },
             { 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 5, 5, 5, 5 },
             { 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 5, 5, 5, 5 },
             { 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 2, 2, 1, 3 },
             { 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 2, 2, 1, 3 },
             { 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 1, 1, 0, 3 },
             { 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 3, 3, 3, 4 },
         };
 

         if (s->segmentation.enabled && s->segmentation.feat[b->seg_id].ref_enabled) {

             av_assert2(s->segmentation.feat[b->seg_id].ref_val != 0);
             b->comp = 0;
             b->ref[0] = s->segmentation.feat[b->seg_id].ref_val - 1;
         } else {
             // read comp_pred flag
             if (s->comppredmode != PRED_SWITCHABLE) {
                 b->comp = s->comppredmode == PRED_COMPREF;
             } else {
                 int c;
 
                 // FIXME add intra as ref=0xff (or -1) to make these easier?
                 if (have_a) {
                     if (have_l) {
                         if (s->above_comp_ctx[col] && s->left_comp_ctx[row7]) {
                             c = 4;
                         } else if (s->above_comp_ctx[col]) {
                             c = 2 + (s->left_intra_ctx[row7] ||
                                      s->left_ref_ctx[row7] == s->fixcompref);
                         } else if (s->left_comp_ctx[row7]) {
                             c = 2 + (s->above_intra_ctx[col] ||
                                      s->above_ref_ctx[col] == s->fixcompref);
                         } else {
                             c = (!s->above_intra_ctx[col] &&
                                  s->above_ref_ctx[col] == s->fixcompref) ^
                             (!s->left_intra_ctx[row7] &&
                              s->left_ref_ctx[row & 7] == s->fixcompref);
                         }
                     } else {
                         c = s->above_comp_ctx[col] ? 3 :
                         (!s->above_intra_ctx[col] && s->above_ref_ctx[col] == s->fixcompref);
                     }
                 } else if (have_l) {
                     c = s->left_comp_ctx[row7] ? 3 :
                     (!s->left_intra_ctx[row7] && s->left_ref_ctx[row7] == s->fixcompref);
                 } else {
                     c = 1;
                 }
                 b->comp = vp56_rac_get_prob(&s->c, s->prob.p.comp[c]);
                 s->counts.comp[c][b->comp]++;
             }
 
             // read actual references
             // FIXME probably cache a few variables here to prevent repetitive
             // memory accesses below
             if (b->comp) /* two references */ {
                 int fix_idx = s->signbias[s->fixcompref], var_idx = !fix_idx, c, bit;
 
                 b->ref[fix_idx] = s->fixcompref;
                 // FIXME can this codeblob be replaced by some sort of LUT?
                 if (have_a) {
                     if (have_l) {
                         if (s->above_intra_ctx[col]) {
                             if (s->left_intra_ctx[row7]) {
                                 c = 2;
                             } else {
                                 c = 1 + 2 * (s->left_ref_ctx[row7] != s->varcompref[1]);
                             }
                         } else if (s->left_intra_ctx[row7]) {
                             c = 1 + 2 * (s->above_ref_ctx[col] != s->varcompref[1]);
                         } else {
                             int refl = s->left_ref_ctx[row7], refa = s->above_ref_ctx[col];
 
                             if (refl == refa && refa == s->varcompref[1]) {
                                 c = 0;
                             } else if (!s->left_comp_ctx[row7] && !s->above_comp_ctx[col]) {
                                 if ((refa == s->fixcompref && refl == s->varcompref[0]) ||
                                     (refl == s->fixcompref && refa == s->varcompref[0])) {
                                     c = 4;
                                 } else {
                                     c = (refa == refl) ? 3 : 1;
                                 }
                             } else if (!s->left_comp_ctx[row7]) {
                                 if (refa == s->varcompref[1] && refl != s->varcompref[1]) {
                                     c = 1;
                                 } else {
                                     c = (refl == s->varcompref[1] &&
                                          refa != s->varcompref[1]) ? 2 : 4;
                                 }
                             } else if (!s->above_comp_ctx[col]) {
                                 if (refl == s->varcompref[1] && refa != s->varcompref[1]) {
                                     c = 1;
                                 } else {
                                     c = (refa == s->varcompref[1] &&
                                          refl != s->varcompref[1]) ? 2 : 4;
                                 }
                             } else {
                                 c = (refl == refa) ? 4 : 2;
                             }
                         }
                     } else {
                         if (s->above_intra_ctx[col]) {
                             c = 2;
                         } else if (s->above_comp_ctx[col]) {
                             c = 4 * (s->above_ref_ctx[col] != s->varcompref[1]);
                         } else {
                             c = 3 * (s->above_ref_ctx[col] != s->varcompref[1]);
                         }
                     }
                 } else if (have_l) {
                     if (s->left_intra_ctx[row7]) {
                         c = 2;
                     } else if (s->left_comp_ctx[row7]) {
                         c = 4 * (s->left_ref_ctx[row7] != s->varcompref[1]);
                     } else {
                         c = 3 * (s->left_ref_ctx[row7] != s->varcompref[1]);
                     }
                 } else {
                     c = 2;
                 }
                 bit = vp56_rac_get_prob(&s->c, s->prob.p.comp_ref[c]);
                 b->ref[var_idx] = s->varcompref[bit];
                 s->counts.comp_ref[c][bit]++;
             } else /* single reference */ {
                 int bit, c;
 
                 if (have_a && !s->above_intra_ctx[col]) {
                     if (have_l && !s->left_intra_ctx[row7]) {
                         if (s->left_comp_ctx[row7]) {
                             if (s->above_comp_ctx[col]) {
                                 c = 1 + (!s->fixcompref || !s->left_ref_ctx[row7] ||
                                          !s->above_ref_ctx[col]);
                             } else {
                                 c = (3 * !s->above_ref_ctx[col]) +
                                     (!s->fixcompref || !s->left_ref_ctx[row7]);
                             }
                         } else if (s->above_comp_ctx[col]) {
                             c = (3 * !s->left_ref_ctx[row7]) +
                                 (!s->fixcompref || !s->above_ref_ctx[col]);
                         } else {
                             c = 2 * !s->left_ref_ctx[row7] + 2 * !s->above_ref_ctx[col];
                         }
                     } else if (s->above_intra_ctx[col]) {
                         c = 2;
                     } else if (s->above_comp_ctx[col]) {
                         c = 1 + (!s->fixcompref || !s->above_ref_ctx[col]);
                     } else {
                         c = 4 * (!s->above_ref_ctx[col]);
                     }
                 } else if (have_l && !s->left_intra_ctx[row7]) {
                     if (s->left_intra_ctx[row7]) {
                         c = 2;
                     } else if (s->left_comp_ctx[row7]) {
                         c = 1 + (!s->fixcompref || !s->left_ref_ctx[row7]);
                     } else {
                         c = 4 * (!s->left_ref_ctx[row7]);
                     }
                 } else {
                     c = 2;
                 }
                 bit = vp56_rac_get_prob(&s->c, s->prob.p.single_ref[c][0]);
                 s->counts.single_ref[c][0][bit]++;
                 if (!bit) {
                     b->ref[0] = 0;
                 } else {
                     // FIXME can this codeblob be replaced by some sort of LUT?
                     if (have_a) {
                         if (have_l) {
                             if (s->left_intra_ctx[row7]) {
                                 if (s->above_intra_ctx[col]) {
                                     c = 2;
                                 } else if (s->above_comp_ctx[col]) {
                                     c = 1 + 2 * (s->fixcompref == 1 ||
                                                  s->above_ref_ctx[col] == 1);
                                 } else if (!s->above_ref_ctx[col]) {
                                     c = 3;
                                 } else {
                                     c = 4 * (s->above_ref_ctx[col] == 1);
                                 }
                             } else if (s->above_intra_ctx[col]) {
                                 if (s->left_intra_ctx[row7]) {
                                     c = 2;
                                 } else if (s->left_comp_ctx[row7]) {
                                     c = 1 + 2 * (s->fixcompref == 1 ||
                                                  s->left_ref_ctx[row7] == 1);
                                 } else if (!s->left_ref_ctx[row7]) {
                                     c = 3;
                                 } else {
                                     c = 4 * (s->left_ref_ctx[row7] == 1);
                                 }
                             } else if (s->above_comp_ctx[col]) {
                                 if (s->left_comp_ctx[row7]) {
                                     if (s->left_ref_ctx[row7] == s->above_ref_ctx[col]) {
                                         c = 3 * (s->fixcompref == 1 ||
                                                  s->left_ref_ctx[row7] == 1);
                                     } else {
                                         c = 2;
                                     }
                                 } else if (!s->left_ref_ctx[row7]) {
                                     c = 1 + 2 * (s->fixcompref == 1 ||
                                                  s->above_ref_ctx[col] == 1);
                                 } else {
                                     c = 3 * (s->left_ref_ctx[row7] == 1) +
                                     (s->fixcompref == 1 || s->above_ref_ctx[col] == 1);
                                 }
                             } else if (s->left_comp_ctx[row7]) {
                                 if (!s->above_ref_ctx[col]) {
                                     c = 1 + 2 * (s->fixcompref == 1 ||
                                                  s->left_ref_ctx[row7] == 1);
                                 } else {
                                     c = 3 * (s->above_ref_ctx[col] == 1) +
                                     (s->fixcompref == 1 || s->left_ref_ctx[row7] == 1);
                                 }
                             } else if (!s->above_ref_ctx[col]) {
                                 if (!s->left_ref_ctx[row7]) {
                                     c = 3;
                                 } else {
                                     c = 4 * (s->left_ref_ctx[row7] == 1);
                                 }
                             } else if (!s->left_ref_ctx[row7]) {
                                 c = 4 * (s->above_ref_ctx[col] == 1);
                             } else {
                                 c = 2 * (s->left_ref_ctx[row7] == 1) +
                                 2 * (s->above_ref_ctx[col] == 1);
                             }
                         } else {
                             if (s->above_intra_ctx[col] ||
                                 (!s->above_comp_ctx[col] && !s->above_ref_ctx[col])) {
                                 c = 2;
                             } else if (s->above_comp_ctx[col]) {
                                 c = 3 * (s->fixcompref == 1 || s->above_ref_ctx[col] == 1);
                             } else {
                                 c = 4 * (s->above_ref_ctx[col] == 1);
                             }
                         }
                     } else if (have_l) {
                         if (s->left_intra_ctx[row7] ||
                             (!s->left_comp_ctx[row7] && !s->left_ref_ctx[row7])) {
                             c = 2;
                         } else if (s->left_comp_ctx[row7]) {
                             c = 3 * (s->fixcompref == 1 || s->left_ref_ctx[row7] == 1);
                         } else {
                             c = 4 * (s->left_ref_ctx[row7] == 1);
                         }
                     } else {
                         c = 2;
                     }
                     bit = vp56_rac_get_prob(&s->c, s->prob.p.single_ref[c][1]);
                     s->counts.single_ref[c][1][bit]++;
                     b->ref[0] = 1 + bit;
                 }
             }
         }
 
         if (b->bs <= BS_8x8) {

             if (s->segmentation.enabled && s->segmentation.feat[b->seg_id].skip_enabled) {

                 b->mode[0] = b->mode[1] = b->mode[2] = b->mode[3] = ZEROMV;
             } else {
                 static const uint8_t off[10] = {
                     3, 0, 0, 1, 0, 0, 0, 0, 0, 0
                 };
 
                 // FIXME this needs to use the LUT tables from find_ref_mvs
                 // because not all are -1,0/0,-1
                 int c = inter_mode_ctx_lut[s->above_mode_ctx[col + off[b->bs]]]
                                           [s->left_mode_ctx[row7 + off[b->bs]]];
 
                 b->mode[0] = vp8_rac_get_tree(&s->c, vp9_inter_mode_tree,
                                               s->prob.p.mv_mode[c]);
                 b->mode[1] = b->mode[2] = b->mode[3] = b->mode[0];
                 s->counts.mv_mode[c][b->mode[0] - 10]++;
             }
         }
 
         if (s->filtermode == FILTER_SWITCHABLE) {
             int c;
 
             if (have_a && s->above_mode_ctx[col] >= NEARESTMV) {
                 if (have_l && s->left_mode_ctx[row7] >= NEARESTMV) {
                     c = s->above_filter_ctx[col] == s->left_filter_ctx[row7] ?
                         s->left_filter_ctx[row7] : 3;
                 } else {
                     c = s->above_filter_ctx[col];
                 }
             } else if (have_l && s->left_mode_ctx[row7] >= NEARESTMV) {
                 c = s->left_filter_ctx[row7];
             } else {
                 c = 3;
             }
 

             filter_id = vp8_rac_get_tree(&s->c, vp9_filter_tree,

                                          s->prob.p.filter[c]);

             s->counts.filter[c][filter_id]++;
             b->filter = vp9_filter_lut[filter_id];

         } else {
             b->filter = s->filtermode;
         }
 
         if (b->bs > BS_8x8) {
             int c = inter_mode_ctx_lut[s->above_mode_ctx[col]][s->left_mode_ctx[row7]];
 
             b->mode[0] = vp8_rac_get_tree(&s->c, vp9_inter_mode_tree,
                                           s->prob.p.mv_mode[c]);
             s->counts.mv_mode[c][b->mode[0] - 10]++;
             fill_mv(s, b->mv[0], b->mode[0], 0);
 
             if (b->bs != BS_8x4) {
                 b->mode[1] = vp8_rac_get_tree(&s->c, vp9_inter_mode_tree,
                                               s->prob.p.mv_mode[c]);
                 s->counts.mv_mode[c][b->mode[1] - 10]++;
                 fill_mv(s, b->mv[1], b->mode[1], 1);
             } else {
                 b->mode[1] = b->mode[0];
                 AV_COPY32(&b->mv[1][0], &b->mv[0][0]);
                 AV_COPY32(&b->mv[1][1], &b->mv[0][1]);
             }
 
             if (b->bs != BS_4x8) {
                 b->mode[2] = vp8_rac_get_tree(&s->c, vp9_inter_mode_tree,
                                               s->prob.p.mv_mode[c]);
                 s->counts.mv_mode[c][b->mode[2] - 10]++;
                 fill_mv(s, b->mv[2], b->mode[2], 2);
 
                 if (b->bs != BS_8x4) {
                     b->mode[3] = vp8_rac_get_tree(&s->c, vp9_inter_mode_tree,
                                                   s->prob.p.mv_mode[c]);
                     s->counts.mv_mode[c][b->mode[3] - 10]++;
                     fill_mv(s, b->mv[3], b->mode[3], 3);
                 } else {
                     b->mode[3] = b->mode[2];
                     AV_COPY32(&b->mv[3][0], &b->mv[2][0]);
                     AV_COPY32(&b->mv[3][1], &b->mv[2][1]);
                 }
             } else {
                 b->mode[2] = b->mode[0];
                 AV_COPY32(&b->mv[2][0], &b->mv[0][0]);
                 AV_COPY32(&b->mv[2][1], &b->mv[0][1]);
                 b->mode[3] = b->mode[1];
                 AV_COPY32(&b->mv[3][0], &b->mv[1][0]);
                 AV_COPY32(&b->mv[3][1], &b->mv[1][1]);
             }
         } else {
             fill_mv(s, b->mv[0], b->mode[0], -1);
             AV_COPY32(&b->mv[1][0], &b->mv[0][0]);
             AV_COPY32(&b->mv[2][0], &b->mv[0][0]);
             AV_COPY32(&b->mv[3][0], &b->mv[0][0]);
             AV_COPY32(&b->mv[1][1], &b->mv[0][1]);
             AV_COPY32(&b->mv[2][1], &b->mv[0][1]);
             AV_COPY32(&b->mv[3][1], &b->mv[0][1]);
         }

 
         vref = b->ref[b->comp ? s->signbias[s->varcompref[0]] : 0];
     }
 
 #if HAVE_FAST_64BIT
 #define SPLAT_CTX(var, val, n) \
     switch (n) { \
     case 1:  var = val;                                    break; \
     case 2:  AV_WN16A(&var, val *             0x0101);     break; \
     case 4:  AV_WN32A(&var, val *         0x01010101);     break; \
     case 8:  AV_WN64A(&var, val * 0x0101010101010101ULL);  break; \
     case 16: { \
         uint64_t v64 = val * 0x0101010101010101ULL; \
         AV_WN64A(              &var,     v64); \
         AV_WN64A(&((uint8_t *) &var)[8], v64); \
         break; \
     } \
     }
 #else
 #define SPLAT_CTX(var, val, n) \
     switch (n) { \
     case 1:  var = val;                         break; \
     case 2:  AV_WN16A(&var, val *     0x0101);  break; \
     case 4:  AV_WN32A(&var, val * 0x01010101);  break; \
     case 8: { \

         uint32_t v32 = val * 0x01010101; \

         AV_WN32A(              &var,     v32); \
         AV_WN32A(&((uint8_t *) &var)[4], v32); \
         break; \
     } \
     case 16: { \

         uint32_t v32 = val * 0x01010101; \

         AV_WN32A(              &var,      v32); \
         AV_WN32A(&((uint8_t *) &var)[4],  v32); \
         AV_WN32A(&((uint8_t *) &var)[8],  v32); \
         AV_WN32A(&((uint8_t *) &var)[12], v32); \
         break; \
     } \

     }

 #endif
 
     switch (bwh_tab[1][b->bs][0]) {
 #define SET_CTXS(dir, off, n) \
     do { \
         SPLAT_CTX(s->dir##_skip_ctx[off],      b->skip,          n); \
         SPLAT_CTX(s->dir##_txfm_ctx[off],      b->tx,            n); \
         SPLAT_CTX(s->dir##_partition_ctx[off], dir##_ctx[b->bs], n); \
         if (!s->keyframe && !s->intraonly) { \
             SPLAT_CTX(s->dir##_intra_ctx[off], b->intra,   n); \
             SPLAT_CTX(s->dir##_comp_ctx[off],  b->comp,    n); \
             SPLAT_CTX(s->dir##_mode_ctx[off],  b->mode[3], n); \
             if (!b->intra) { \
                 SPLAT_CTX(s->dir##_ref_ctx[off], vref, n); \
                 if (s->filtermode == FILTER_SWITCHABLE) { \
                     SPLAT_CTX(s->dir##_filter_ctx[off], filter_id, n); \
                 } \
             } \
         } \
     } while (0)
     case 1: SET_CTXS(above, col, 1); break;
     case 2: SET_CTXS(above, col, 2); break;
     case 4: SET_CTXS(above, col, 4); break;
     case 8: SET_CTXS(above, col, 8); break;
     }
     switch (bwh_tab[1][b->bs][1]) {
     case 1: SET_CTXS(left, row7, 1); break;
     case 2: SET_CTXS(left, row7, 2); break;
     case 4: SET_CTXS(left, row7, 4); break;
     case 8: SET_CTXS(left, row7, 8); break;
     }
 #undef SPLAT_CTX
 #undef SET_CTXS

 
     if (!s->keyframe && !s->intraonly) {
         if (b->bs > BS_8x8) {
             int mv0 = AV_RN32A(&b->mv[3][0]), mv1 = AV_RN32A(&b->mv[3][1]);
 
             AV_COPY32(&s->left_mv_ctx[row7 * 2 + 0][0], &b->mv[1][0]);
             AV_COPY32(&s->left_mv_ctx[row7 * 2 + 0][1], &b->mv[1][1]);
             AV_WN32A(&s->left_mv_ctx[row7 * 2 + 1][0], mv0);
             AV_WN32A(&s->left_mv_ctx[row7 * 2 + 1][1], mv1);
             AV_COPY32(&s->above_mv_ctx[col * 2 + 0][0], &b->mv[2][0]);
             AV_COPY32(&s->above_mv_ctx[col * 2 + 0][1], &b->mv[2][1]);
             AV_WN32A(&s->above_mv_ctx[col * 2 + 1][0], mv0);
             AV_WN32A(&s->above_mv_ctx[col * 2 + 1][1], mv1);
         } else {
             int n, mv0 = AV_RN32A(&b->mv[3][0]), mv1 = AV_RN32A(&b->mv[3][1]);
 
             for (n = 0; n < w4 * 2; n++) {
                 AV_WN32A(&s->above_mv_ctx[col * 2 + n][0], mv0);
                 AV_WN32A(&s->above_mv_ctx[col * 2 + n][1], mv1);
             }
             for (n = 0; n < h4 * 2; n++) {
                 AV_WN32A(&s->left_mv_ctx[row7 * 2 + n][0], mv0);
                 AV_WN32A(&s->left_mv_ctx[row7 * 2 + n][1], mv1);
             }
         }
     }
 
     // FIXME kinda ugly
     for (y = 0; y < h4; y++) {
         int x, o = (row + y) * s->sb_cols * 8 + col;

         struct VP9mvrefPair *mv = &s->frames[CUR_FRAME].mv[o];

 
         if (b->intra) {
             for (x = 0; x < w4; x++) {

                 mv[x].ref[0] =
                 mv[x].ref[1] = -1;

             }
         } else if (b->comp) {
             for (x = 0; x < w4; x++) {

                 mv[x].ref[0] = b->ref[0];
                 mv[x].ref[1] = b->ref[1];
                 AV_COPY32(&mv[x].mv[0], &b->mv[3][0]);
                 AV_COPY32(&mv[x].mv[1], &b->mv[3][1]);

             }
         } else {
             for (x = 0; x < w4; x++) {

                 mv[x].ref[0] = b->ref[0];
                 mv[x].ref[1] = -1;
                 AV_COPY32(&mv[x].mv[0], &b->mv[3][0]);

             }
         }
     }
 }
 

 // FIXME merge cnt/eob arguments?
 static av_always_inline int
 decode_coeffs_b_generic(VP56RangeCoder *c, int16_t *coef, int n_coeffs,

                         int is_tx32x32, int is8bitsperpixel, int bpp, unsigned (*cnt)[6][3],

                         unsigned (*eob)[6][2], uint8_t (*p)[6][11],
                         int nnz, const int16_t *scan, const int16_t (*nb)[2],
                         const int16_t *band_counts, const int16_t *qmul)

 {
     int i = 0, band = 0, band_left = band_counts[band];
     uint8_t *tp = p[0][nnz];
     uint8_t cache[1024];
 
     do {
         int val, rc;
 
         val = vp56_rac_get_prob_branchy(c, tp[0]); // eob
         eob[band][nnz][val]++;
         if (!val)
             break;
 
     skip_eob:
         if (!vp56_rac_get_prob_branchy(c, tp[1])) { // zero
             cnt[band][nnz][0]++;
             if (!--band_left)
                 band_left = band_counts[++band];
             cache[scan[i]] = 0;
             nnz = (1 + cache[nb[i][0]] + cache[nb[i][1]]) >> 1;
             tp = p[band][nnz];
             if (++i == n_coeffs)
                 break; //invalid input; blocks should end with EOB
             goto skip_eob;
         }
 
         rc = scan[i];
         if (!vp56_rac_get_prob_branchy(c, tp[2])) { // one
             cnt[band][nnz][1]++;
             val = 1;
             cache[rc] = 1;
         } else {
             // fill in p[3-10] (model fill) - only once per frame for each pos
             if (!tp[3])
                 memcpy(&tp[3], vp9_model_pareto8[tp[2]], 8);
 
             cnt[band][nnz][2]++;
             if (!vp56_rac_get_prob_branchy(c, tp[3])) { // 2, 3, 4
                 if (!vp56_rac_get_prob_branchy(c, tp[4])) {
                     cache[rc] = val = 2;
                 } else {
                     val = 3 + vp56_rac_get_prob(c, tp[5]);
                     cache[rc] = 3;
                 }
             } else if (!vp56_rac_get_prob_branchy(c, tp[6])) { // cat1/2
                 cache[rc] = 4;
                 if (!vp56_rac_get_prob_branchy(c, tp[7])) {
                     val = 5 + vp56_rac_get_prob(c, 159);
                 } else {

                     val  = 7 + (vp56_rac_get_prob(c, 165) << 1);
                     val +=      vp56_rac_get_prob(c, 145);

                 }
             } else { // cat 3-6
                 cache[rc] = 5;
                 if (!vp56_rac_get_prob_branchy(c, tp[8])) {
                     if (!vp56_rac_get_prob_branchy(c, tp[9])) {

                         val  = 11 + (vp56_rac_get_prob(c, 173) << 2);
                         val +=      (vp56_rac_get_prob(c, 148) << 1);
                         val +=       vp56_rac_get_prob(c, 140);

                     } else {

                         val  = 19 + (vp56_rac_get_prob(c, 176) << 3);
                         val +=      (vp56_rac_get_prob(c, 155) << 2);
                         val +=      (vp56_rac_get_prob(c, 140) << 1);
                         val +=       vp56_rac_get_prob(c, 135);

                     }
                 } else if (!vp56_rac_get_prob_branchy(c, tp[10])) {

                     val  = 35 + (vp56_rac_get_prob(c, 180) << 4);
                     val +=      (vp56_rac_get_prob(c, 157) << 3);
                     val +=      (vp56_rac_get_prob(c, 141) << 2);
                     val +=      (vp56_rac_get_prob(c, 134) << 1);
                     val +=       vp56_rac_get_prob(c, 130);

                 } else {

                     val = 67;
                     if (!is8bitsperpixel) {
                         if (bpp == 12) {
                             val += vp56_rac_get_prob(c, 255) << 17;
                             val += vp56_rac_get_prob(c, 255) << 16;
                         }
                         val +=  (vp56_rac_get_prob(c, 255) << 15);
                         val +=  (vp56_rac_get_prob(c, 255) << 14);
                     }
                     val +=      (vp56_rac_get_prob(c, 254) << 13);

                     val +=      (vp56_rac_get_prob(c, 254) << 12);
                     val +=      (vp56_rac_get_prob(c, 254) << 11);
                     val +=      (vp56_rac_get_prob(c, 252) << 10);
                     val +=      (vp56_rac_get_prob(c, 249) << 9);
                     val +=      (vp56_rac_get_prob(c, 243) << 8);
                     val +=      (vp56_rac_get_prob(c, 230) << 7);
                     val +=      (vp56_rac_get_prob(c, 196) << 6);
                     val +=      (vp56_rac_get_prob(c, 177) << 5);
                     val +=      (vp56_rac_get_prob(c, 153) << 4);
                     val +=      (vp56_rac_get_prob(c, 140) << 3);
                     val +=      (vp56_rac_get_prob(c, 133) << 2);
                     val +=      (vp56_rac_get_prob(c, 130) << 1);
                     val +=       vp56_rac_get_prob(c, 129);

                 }
             }
         }

 #define STORE_COEF(c, i, v) do { \
     if (is8bitsperpixel) { \
         c[i] = v; \
     } else { \
         AV_WN32A(&c[i * 2], v); \
     } \
 } while (0)

         if (!--band_left)
             band_left = band_counts[++band];

         if (is_tx32x32)

             STORE_COEF(coef, rc, ((vp8_rac_get(c) ? -val : val) * qmul[!!i]) / 2);

         else

             STORE_COEF(coef, rc, (vp8_rac_get(c) ? -val : val) * qmul[!!i]);

         nnz = (1 + cache[nb[i][0]] + cache[nb[i][1]]) >> 1;
         tp = p[band][nnz];
     } while (++i < n_coeffs);
 
     return i;
 }
 

 static int decode_coeffs_b_8bpp(VP9Context *s, int16_t *coef, int n_coeffs,
                                 unsigned (*cnt)[6][3], unsigned (*eob)[6][2],
                                 uint8_t (*p)[6][11], int nnz, const int16_t *scan,
                                 const int16_t (*nb)[2], const int16_t *band_counts,
                                 const int16_t *qmul)
 {
     return decode_coeffs_b_generic(&s->c, coef, n_coeffs, 0, 1, 8, cnt, eob, p,
                                    nnz, scan, nb, band_counts, qmul);
 }
 
 static int decode_coeffs_b32_8bpp(VP9Context *s, int16_t *coef, int n_coeffs,
                                   unsigned (*cnt)[6][3], unsigned (*eob)[6][2],
                                   uint8_t (*p)[6][11], int nnz, const int16_t *scan,
                                   const int16_t (*nb)[2], const int16_t *band_counts,
                                   const int16_t *qmul)

 {

     return decode_coeffs_b_generic(&s->c, coef, n_coeffs, 1, 1, 8, cnt, eob, p,

                                    nnz, scan, nb, band_counts, qmul);
 }
 

 static int decode_coeffs_b_16bpp(VP9Context *s, int16_t *coef, int n_coeffs,
                                  unsigned (*cnt)[6][3], unsigned (*eob)[6][2],
                                  uint8_t (*p)[6][11], int nnz, const int16_t *scan,
                                  const int16_t (*nb)[2], const int16_t *band_counts,
                                  const int16_t *qmul)

 {

     return decode_coeffs_b_generic(&s->c, coef, n_coeffs, 0, 0, s->bpp, cnt, eob, p,

                                    nnz, scan, nb, band_counts, qmul);
 }
 

 static int decode_coeffs_b32_16bpp(VP9Context *s, int16_t *coef, int n_coeffs,
                                    unsigned (*cnt)[6][3], unsigned (*eob)[6][2],
                                    uint8_t (*p)[6][11], int nnz, const int16_t *scan,
                                    const int16_t (*nb)[2], const int16_t *band_counts,
                                    const int16_t *qmul)
 {
     return decode_coeffs_b_generic(&s->c, coef, n_coeffs, 1, 0, s->bpp, cnt, eob, p,
                                    nnz, scan, nb, band_counts, qmul);
 }
 

 static av_always_inline int decode_coeffs(AVCodecContext *ctx, int is8bitsperpixel)

 {
     VP9Context *s = ctx->priv_data;

     VP9Block *b = s->b;

     int row = s->row, col = s->col;

     uint8_t (*p)[6][11] = s->prob.coef[b->tx][0 /* y */][!b->intra];
     unsigned (*c)[6][3] = s->counts.coef[b->tx][0 /* y */][!b->intra];
     unsigned (*e)[6][2] = s->counts.eob[b->tx][0 /* y */][!b->intra];
     int w4 = bwh_tab[1][b->bs][0] << 1, h4 = bwh_tab[1][b->bs][1] << 1;
     int end_x = FFMIN(2 * (s->cols - col), w4);
     int end_y = FFMIN(2 * (s->rows - row), h4);

     int n, pl, x, y, res;

     int16_t (*qmul)[2] = s->segmentation.feat[b->seg_id].qmul;
     int tx = 4 * s->lossless + b->tx;

     const int16_t * const *yscans = vp9_scans[tx];
     const int16_t (* const *ynbs)[2] = vp9_scans_nb[tx];

     const int16_t *uvscan = vp9_scans[b->uvtx][DCT_DCT];
     const int16_t (*uvnb)[2] = vp9_scans_nb[b->uvtx][DCT_DCT];
     uint8_t *a = &s->above_y_nnz_ctx[col * 2];
     uint8_t *l = &s->left_y_nnz_ctx[(row & 7) << 1];

     static const int16_t band_counts[4][8] = {

         { 1, 2, 3, 4,  3,   16 - 13 },
         { 1, 2, 3, 4, 11,   64 - 21 },
         { 1, 2, 3, 4, 11,  256 - 21 },
         { 1, 2, 3, 4, 11, 1024 - 21 },
     };
     const int16_t *y_band_counts = band_counts[b->tx];
     const int16_t *uv_band_counts = band_counts[b->uvtx];

     int bytesperpixel = is8bitsperpixel ? 1 : 2;

     int total_coeff = 0;

 #define MERGE(la, end, step, rd) \
     for (n = 0; n < end; n += step) \
         la[n] = !!rd(&la[n])
 #define MERGE_CTX(step, rd) \
     do { \
         MERGE(l, end_y, step, rd); \
         MERGE(a, end_x, step, rd); \
     } while (0)
 

 #define DECODE_Y_COEF_LOOP(step, mode_index, v) \
     for (n = 0, y = 0; y < end_y; y += step) { \
         for (x = 0; x < end_x; x += step, n += step * step) { \
             enum TxfmType txtp = vp9_intra_txfm_type[b->mode[mode_index]]; \

             res = (is8bitsperpixel ? decode_coeffs_b##v##_8bpp : decode_coeffs_b##v##_16bpp) \
                                     (s, s->block + 16 * n * bytesperpixel, 16 * step * step, \

                                      c, e, p, a[x] + l[y], yscans[txtp], \
                                      ynbs[txtp], y_band_counts, qmul[0]); \
             a[x] = l[y] = !!res; \

             total_coeff |= !!res; \

             if (step >= 4) { \
                 AV_WN16A(&s->eob[n], res); \
             } else { \
                 s->eob[n] = res; \
             } \
         } \

     }

 #define SPLAT(la, end, step, cond) \
     if (step == 2) { \
         for (n = 1; n < end; n += step) \
             la[n] = la[n - 1]; \
     } else if (step == 4) { \
         if (cond) { \
             for (n = 0; n < end; n += step) \
                 AV_WN32A(&la[n], la[n] * 0x01010101); \
         } else { \
             for (n = 0; n < end; n += step) \
                 memset(&la[n + 1], la[n], FFMIN(end - n - 1, 3)); \
         } \
     } else /* step == 8 */ { \
         if (cond) { \
             if (HAVE_FAST_64BIT) { \
                 for (n = 0; n < end; n += step) \
                     AV_WN64A(&la[n], la[n] * 0x0101010101010101ULL); \
             } else { \
                 for (n = 0; n < end; n += step) { \
                     uint32_t v32 = la[n] * 0x01010101; \
                     AV_WN32A(&la[n],     v32); \
                     AV_WN32A(&la[n + 4], v32); \
                 } \
             } \
         } else { \
             for (n = 0; n < end; n += step) \
                 memset(&la[n + 1], la[n], FFMIN(end - n - 1, 7)); \
         } \
     }
 #define SPLAT_CTX(step) \
     do { \
         SPLAT(a, end_x, step, end_x == w4); \
         SPLAT(l, end_y, step, end_y == h4); \
     } while (0)

 
     /* y tokens */

     switch (b->tx) {

     case TX_4X4:
         DECODE_Y_COEF_LOOP(1, b->bs > BS_8x8 ? n : 0,);
         break;
     case TX_8X8:
         MERGE_CTX(2, AV_RN16A);
         DECODE_Y_COEF_LOOP(2, 0,);
         SPLAT_CTX(2);
         break;
     case TX_16X16:
         MERGE_CTX(4, AV_RN32A);
         DECODE_Y_COEF_LOOP(4, 0,);
         SPLAT_CTX(4);
         break;
     case TX_32X32:
         MERGE_CTX(8, AV_RN64A);
         DECODE_Y_COEF_LOOP(8, 0, 32);
         SPLAT_CTX(8);
         break;
     }
 

 #define DECODE_UV_COEF_LOOP(step, v) \

     for (n = 0, y = 0; y < end_y; y += step) { \
         for (x = 0; x < end_x; x += step, n += step * step) { \

             res = (is8bitsperpixel ? decode_coeffs_b##v##_8bpp : decode_coeffs_b##v##_16bpp) \
                                     (s, s->uvblock[pl] + 16 * n * bytesperpixel, \
                                      16 * step * step, c, e, p, a[x] + l[y], \
                                      uvscan, uvnb, uv_band_counts, qmul[1]); \

             a[x] = l[y] = !!res; \

             total_coeff |= !!res; \

             if (step >= 4) { \
                 AV_WN16A(&s->uveob[pl][n], res); \
             } else { \
                 s->uveob[pl][n] = res; \
             } \

         } \

     }
 
     p = s->prob.coef[b->uvtx][1 /* uv */][!b->intra];
     c = s->counts.coef[b->uvtx][1 /* uv */][!b->intra];
     e = s->counts.eob[b->uvtx][1 /* uv */][!b->intra];

     w4 >>= s->ss_h;
     end_x >>= s->ss_h;
     h4 >>= s->ss_v;
     end_y >>= s->ss_v;

     for (pl = 0; pl < 2; pl++) {

         a = &s->above_uv_nnz_ctx[pl][col << !s->ss_h];
         l = &s->left_uv_nnz_ctx[pl][(row & 7) << !s->ss_v];

         switch (b->uvtx) {

         case TX_4X4:

             DECODE_UV_COEF_LOOP(1,);

             break;
         case TX_8X8:
             MERGE_CTX(2, AV_RN16A);

             DECODE_UV_COEF_LOOP(2,);

             SPLAT_CTX(2);
             break;
         case TX_16X16:
             MERGE_CTX(4, AV_RN32A);

             DECODE_UV_COEF_LOOP(4,);

             SPLAT_CTX(4);
             break;
         case TX_32X32:
             MERGE_CTX(8, AV_RN64A);

             DECODE_UV_COEF_LOOP(8, 32);

             SPLAT_CTX(8);
             break;

         }
     }

 
     return total_coeff;

 }
 

 static int decode_coeffs_8bpp(AVCodecContext *ctx)

 {

     return decode_coeffs(ctx, 1);

 }
 

 static int decode_coeffs_16bpp(AVCodecContext *ctx)

 {

     return decode_coeffs(ctx, 0);

 }
 

 static av_always_inline int check_intra_mode(VP9Context *s, int mode, uint8_t **a,
                                              uint8_t *dst_edge, ptrdiff_t stride_edge,
                                              uint8_t *dst_inner, ptrdiff_t stride_inner,
                                              uint8_t *l, int col, int x, int w,
                                              int row, int y, enum TxfmMode tx,

                                              int p, int ss_h, int ss_v, int bytesperpixel)

 {
     int have_top = row > 0 || y > 0;
     int have_left = col > s->tiling.tile_col_start || x > 0;
     int have_right = x < w - 1;

     int bpp = s->bpp;

     static const uint8_t mode_conv[10][2 /* have_left */][2 /* have_top */] = {
         [VERT_PRED]            = { { DC_127_PRED,          VERT_PRED },
                                    { DC_127_PRED,          VERT_PRED } },
         [HOR_PRED]             = { { DC_129_PRED,          DC_129_PRED },
                                    { HOR_PRED,             HOR_PRED } },
         [DC_PRED]              = { { DC_128_PRED,          TOP_DC_PRED },
                                    { LEFT_DC_PRED,         DC_PRED } },
         [DIAG_DOWN_LEFT_PRED]  = { { DC_127_PRED,          DIAG_DOWN_LEFT_PRED },
                                    { DC_127_PRED,          DIAG_DOWN_LEFT_PRED } },
         [DIAG_DOWN_RIGHT_PRED] = { { DIAG_DOWN_RIGHT_PRED, DIAG_DOWN_RIGHT_PRED },
                                    { DIAG_DOWN_RIGHT_PRED, DIAG_DOWN_RIGHT_PRED } },
         [VERT_RIGHT_PRED]      = { { VERT_RIGHT_PRED,      VERT_RIGHT_PRED },
                                    { VERT_RIGHT_PRED,      VERT_RIGHT_PRED } },
         [HOR_DOWN_PRED]        = { { HOR_DOWN_PRED,        HOR_DOWN_PRED },
                                    { HOR_DOWN_PRED,        HOR_DOWN_PRED } },
         [VERT_LEFT_PRED]       = { { DC_127_PRED,          VERT_LEFT_PRED },
                                    { DC_127_PRED,          VERT_LEFT_PRED } },
         [HOR_UP_PRED]          = { { DC_129_PRED,          DC_129_PRED },
                                    { HOR_UP_PRED,          HOR_UP_PRED } },
         [TM_VP8_PRED]          = { { DC_129_PRED,          VERT_PRED },
                                    { HOR_PRED,             TM_VP8_PRED } },
     };
     static const struct {
         uint8_t needs_left:1;
         uint8_t needs_top:1;
         uint8_t needs_topleft:1;
         uint8_t needs_topright:1;

         uint8_t invert_left:1;

     } edges[N_INTRA_PRED_MODES] = {
         [VERT_PRED]            = { .needs_top  = 1 },
         [HOR_PRED]             = { .needs_left = 1 },
         [DC_PRED]              = { .needs_top  = 1, .needs_left = 1 },
         [DIAG_DOWN_LEFT_PRED]  = { .needs_top  = 1, .needs_topright = 1 },
         [DIAG_DOWN_RIGHT_PRED] = { .needs_left = 1, .needs_top = 1, .needs_topleft = 1 },
         [VERT_RIGHT_PRED]      = { .needs_left = 1, .needs_top = 1, .needs_topleft = 1 },
         [HOR_DOWN_PRED]        = { .needs_left = 1, .needs_top = 1, .needs_topleft = 1 },
         [VERT_LEFT_PRED]       = { .needs_top  = 1, .needs_topright = 1 },

         [HOR_UP_PRED]          = { .needs_left = 1, .invert_left = 1 },

         [TM_VP8_PRED]          = { .needs_left = 1, .needs_top = 1, .needs_topleft = 1 },
         [LEFT_DC_PRED]         = { .needs_left = 1 },
         [TOP_DC_PRED]          = { .needs_top  = 1 },
         [DC_128_PRED]          = { 0 },
         [DC_127_PRED]          = { 0 },
         [DC_129_PRED]          = { 0 }
     };
 
     av_assert2(mode >= 0 && mode < 10);
     mode = mode_conv[mode][have_left][have_top];
     if (edges[mode].needs_top) {
         uint8_t *top, *topleft;

         int n_px_need = 4 << tx, n_px_have = (((s->cols - col) << !ss_h) - x) * 4;

         int n_px_need_tr = 0;
 
         if (tx == TX_4X4 && edges[mode].needs_topright && have_right)
             n_px_need_tr = 4;
 
         // if top of sb64-row, use s->intra_pred_data[] instead of
         // dst[-stride] for intra prediction (it contains pre- instead of
         // post-loopfilter data)
         if (have_top) {
             top = !(row & 7) && !y ?

                 s->intra_pred_data[p] + (col * (8 >> ss_h) + x * 4) * bytesperpixel :

                 y == 0 ? &dst_edge[-stride_edge] : &dst_inner[-stride_inner];
             if (have_left)
                 topleft = !(row & 7) && !y ?

                     s->intra_pred_data[p] + (col * (8 >> ss_h) + x * 4) * bytesperpixel :

                     y == 0 || x == 0 ? &dst_edge[-stride_edge] :
                     &dst_inner[-stride_inner];
         }
 
         if (have_top &&
             (!edges[mode].needs_topleft || (have_left && top == topleft)) &&
             (tx != TX_4X4 || !edges[mode].needs_topright || have_right) &&
             n_px_need + n_px_need_tr <= n_px_have) {
             *a = top;
         } else {
             if (have_top) {
                 if (n_px_need <= n_px_have) {

                     memcpy(*a, top, n_px_need * bytesperpixel);

                 } else {

 #define memset_bpp(c, i1, v, i2, num) do { \
     if (bytesperpixel == 1) { \
         memset(&(c)[(i1)], (v)[(i2)], (num)); \
     } else { \
         int n, val = AV_RN16A(&(v)[(i2) * 2]); \
         for (n = 0; n < (num); n++) { \
             AV_WN16A(&(c)[((i1) + n) * 2], val); \
         } \
     } \
 } while (0)
                     memcpy(*a, top, n_px_have * bytesperpixel);
                     memset_bpp(*a, n_px_have, (*a), n_px_have - 1, n_px_need - n_px_have);

                 }
             } else {

 #define memset_val(c, val, num) do { \
     if (bytesperpixel == 1) { \
         memset((c), (val), (num)); \
     } else { \
         int n; \
         for (n = 0; n < (num); n++) { \
             AV_WN16A(&(c)[n * 2], (val)); \
         } \
     } \
 } while (0)
                 memset_val(*a, (128 << (bpp - 8)) - 1, n_px_need);

             }
             if (edges[mode].needs_topleft) {
                 if (have_left && have_top) {

 #define assign_bpp(c, i1, v, i2) do { \
     if (bytesperpixel == 1) { \
         (c)[(i1)] = (v)[(i2)]; \
     } else { \
         AV_COPY16(&(c)[(i1) * 2], &(v)[(i2) * 2]); \
     } \
 } while (0)
                     assign_bpp(*a, -1, topleft, -1);

                 } else {

 #define assign_val(c, i, v) do { \
     if (bytesperpixel == 1) { \
         (c)[(i)] = (v); \
     } else { \
         AV_WN16A(&(c)[(i) * 2], (v)); \
     } \
 } while (0)
                     assign_val((*a), -1, (128 << (bpp - 8)) + (have_top ? +1 : -1));

                 }
             }
             if (tx == TX_4X4 && edges[mode].needs_topright) {
                 if (have_top && have_right &&
                     n_px_need + n_px_need_tr <= n_px_have) {

                     memcpy(&(*a)[4 * bytesperpixel], &top[4 * bytesperpixel], 4 * bytesperpixel);

                 } else {

                     memset_bpp(*a, 4, *a, 3, 4);

                 }
             }
         }
     }
     if (edges[mode].needs_left) {
         if (have_left) {

             int n_px_need = 4 << tx, i, n_px_have = (((s->rows - row) << !ss_v) - y) * 4;

             uint8_t *dst = x == 0 ? dst_edge : dst_inner;
             ptrdiff_t stride = x == 0 ? stride_edge : stride_inner;
 

             if (edges[mode].invert_left) {
                 if (n_px_need <= n_px_have) {
                     for (i = 0; i < n_px_need; i++)

                         assign_bpp(l, i, &dst[i * stride], -1);

                 } else {
                     for (i = 0; i < n_px_have; i++)

                         assign_bpp(l, i, &dst[i * stride], -1);
                     memset_bpp(l, n_px_have, l, n_px_have - 1, n_px_need - n_px_have);

                 }

             } else {

                 if (n_px_need <= n_px_have) {
                     for (i = 0; i < n_px_need; i++)

                         assign_bpp(l, n_px_need - 1 - i, &dst[i * stride], -1);

                 } else {
                     for (i = 0; i < n_px_have; i++)

                         assign_bpp(l, n_px_need - 1 - i, &dst[i * stride], -1);
                     memset_bpp(l, 0, l, n_px_need - n_px_have, n_px_need - n_px_have);

                 }

             }
         } else {

             memset_val(l, (128 << (bpp - 8)) + 1, 4 << tx);

         }
     }
 
     return mode;
 }
 

 static av_always_inline void intra_recon(AVCodecContext *ctx, ptrdiff_t y_off,
                                          ptrdiff_t uv_off, int bytesperpixel)

 {
     VP9Context *s = ctx->priv_data;

     VP9Block *b = s->b;

     int row = s->row, col = s->col;

     int w4 = bwh_tab[1][b->bs][0] << 1, step1d = 1 << b->tx, n;
     int h4 = bwh_tab[1][b->bs][1] << 1, x, y, step = 1 << (b->tx * 2);
     int end_x = FFMIN(2 * (s->cols - col), w4);
     int end_y = FFMIN(2 * (s->rows - row), h4);
     int tx = 4 * s->lossless + b->tx, uvtx = b->uvtx + 4 * s->lossless;
     int uvstep1d = 1 << b->uvtx, p;

     uint8_t *dst = s->dst[0], *dst_r = s->frames[CUR_FRAME].tf.f->data[0] + y_off;

     LOCAL_ALIGNED_32(uint8_t, a_buf, [96]);
     LOCAL_ALIGNED_32(uint8_t, l, [64]);

 
     for (n = 0, y = 0; y < end_y; y += step1d) {
         uint8_t *ptr = dst, *ptr_r = dst_r;

         for (x = 0; x < end_x; x += step1d, ptr += 4 * step1d * bytesperpixel,
                                ptr_r += 4 * step1d * bytesperpixel, n += step) {

             int mode = b->mode[b->bs > BS_8x8 && b->tx == TX_4X4 ?
                                y * 2 + x : 0];

             uint8_t *a = &a_buf[32];

             enum TxfmType txtp = vp9_intra_txfm_type[mode];

             int eob = b->skip ? 0 : b->tx > TX_8X8 ? AV_RN16A(&s->eob[n]) : s->eob[n];

             mode = check_intra_mode(s, mode, &a, ptr_r,
                                     s->frames[CUR_FRAME].tf.f->linesize[0],

                                     ptr, s->y_stride, l,

                                     col, x, w4, row, y, b->tx, 0, 0, 0, bytesperpixel);

             s->dsp.intra_pred[b->tx][mode](ptr, s->y_stride, l, a);

             if (eob)

                 s->dsp.itxfm_add[tx][txtp](ptr, s->y_stride,

                                            s->block + 16 * n * bytesperpixel, eob);

         }

         dst_r += 4 * step1d * s->frames[CUR_FRAME].tf.f->linesize[0];

         dst   += 4 * step1d * s->y_stride;

     }
 
     // U/V

     w4 >>= s->ss_h;
     end_x >>= s->ss_h;
     end_y >>= s->ss_v;

     step = 1 << (b->uvtx * 2);
     for (p = 0; p < 2; p++) {

         dst   = s->dst[1 + p];

         dst_r = s->frames[CUR_FRAME].tf.f->data[1 + p] + uv_off;

         for (n = 0, y = 0; y < end_y; y += uvstep1d) {
             uint8_t *ptr = dst, *ptr_r = dst_r;

             for (x = 0; x < end_x; x += uvstep1d, ptr += 4 * uvstep1d * bytesperpixel,
                                    ptr_r += 4 * uvstep1d * bytesperpixel, n += step) {

                 int mode = b->uvmode;

                 uint8_t *a = &a_buf[32];

                 int eob = b->skip ? 0 : b->uvtx > TX_8X8 ? AV_RN16A(&s->uveob[p][n]) : s->uveob[p][n];

                 mode = check_intra_mode(s, mode, &a, ptr_r,
                                         s->frames[CUR_FRAME].tf.f->linesize[1],

                                         ptr, s->uv_stride, l, col, x, w4, row, y,

                                         b->uvtx, p + 1, s->ss_h, s->ss_v, bytesperpixel);

                 s->dsp.intra_pred[b->uvtx][mode](ptr, s->uv_stride, l, a);

                 if (eob)

                     s->dsp.itxfm_add[uvtx][DCT_DCT](ptr, s->uv_stride,

                                                     s->uvblock[p] + 16 * n * bytesperpixel, eob);

             }

             dst_r += 4 * uvstep1d * s->frames[CUR_FRAME].tf.f->linesize[1];

             dst   += 4 * uvstep1d * s->uv_stride;

         }
     }
 }
 

 static void intra_recon_8bpp(AVCodecContext *ctx, ptrdiff_t y_off, ptrdiff_t uv_off)
 {
     intra_recon(ctx, y_off, uv_off, 1);
 }
 
 static void intra_recon_16bpp(AVCodecContext *ctx, ptrdiff_t y_off, ptrdiff_t uv_off)
 {
     intra_recon(ctx, y_off, uv_off, 2);
 }
 

 static av_always_inline void mc_luma_scaled(VP9Context *s, vp9_scaled_mc_func smc,
                                             uint8_t *dst, ptrdiff_t dst_stride,
                                             const uint8_t *ref, ptrdiff_t ref_stride,
                                             ThreadFrame *ref_frame,

                                             ptrdiff_t y, ptrdiff_t x, const VP56mv *in_mv,

                                             int px, int py, int pw, int ph,

                                             int bw, int bh, int w, int h, int bytesperpixel,

                                             const uint16_t *scale, const uint8_t *step)
 {

 #define scale_mv(n, dim) (((int64_t)(n) * scale[dim]) >> 14)

     int mx, my;
     int refbw_m1, refbh_m1;
     int th;
     VP56mv mv;
 

     mv.x = av_clip(in_mv->x, -(x + pw - px + 4) << 3, (s->cols * 8 - x + px + 3) << 3);
     mv.y = av_clip(in_mv->y, -(y + ph - py + 4) << 3, (s->rows * 8 - y + py + 3) << 3);

     // BUG libvpx seems to scale the two components separately. This introduces
     // rounding errors but we have to reproduce them to be exactly compatible
     // with the output from libvpx...

     mx = scale_mv(mv.x * 2, 0) + scale_mv(x * 16, 0);
     my = scale_mv(mv.y * 2, 1) + scale_mv(y * 16, 1);

 
     y = my >> 4;
     x = mx >> 4;

     ref += y * ref_stride + x * bytesperpixel;

     mx &= 15;
     my &= 15;
     refbw_m1 = ((bw - 1) * step[0] + mx) >> 4;
     refbh_m1 = ((bh - 1) * step[1] + my) >> 4;
     // FIXME bilinear filter only needs 0/1 pixels, not 3/4
     // we use +7 because the last 7 pixels of each sbrow can be changed in
     // the longest loopfilter of the next sbrow
     th = (y + refbh_m1 + 4 + 7) >> 6;
     ff_thread_await_progress(ref_frame, FFMAX(th, 0), 0);
     if (x < 3 || y < 3 || x + 4 >= w - refbw_m1 || y + 4 >= h - refbh_m1) {
         s->vdsp.emulated_edge_mc(s->edge_emu_buffer,

                                  ref - 3 * ref_stride - 3 * bytesperpixel,
                                  288, ref_stride,

                                  refbw_m1 + 8, refbh_m1 + 8,
                                  x - 3, y - 3, w, h);

         ref = s->edge_emu_buffer + 3 * 288 + 3 * bytesperpixel;
         ref_stride = 288;

     }
     smc(dst, dst_stride, ref, ref_stride, bh, mx, my, step[0], step[1]);
 }
 
 static av_always_inline void mc_chroma_scaled(VP9Context *s, vp9_scaled_mc_func smc,
                                               uint8_t *dst_u, uint8_t *dst_v,
                                               ptrdiff_t dst_stride,
                                               const uint8_t *ref_u, ptrdiff_t src_stride_u,
                                               const uint8_t *ref_v, ptrdiff_t src_stride_v,
                                               ThreadFrame *ref_frame,

                                               ptrdiff_t y, ptrdiff_t x, const VP56mv *in_mv,

                                               int px, int py, int pw, int ph,

                                               int bw, int bh, int w, int h, int bytesperpixel,

                                               const uint16_t *scale, const uint8_t *step)
 {

     int mx, my;

     int refbw_m1, refbh_m1;
     int th;

     VP56mv mv;

     if (s->ss_h) {
         // BUG https://code.google.com/p/webm/issues/detail?id=820

         mv.x = av_clip(in_mv->x, -(x + pw - px + 4) << 4, (s->cols * 4 - x + px + 3) << 4);

         mx = scale_mv(mv.x, 0) + (scale_mv(x * 16, 0) & ~15) + (scale_mv(x * 32, 0) & 15);

     } else {

         mv.x = av_clip(in_mv->x, -(x + pw - px + 4) << 3, (s->cols * 8 - x + px + 3) << 3);

         mx = scale_mv(mv.x << 1, 0) + scale_mv(x * 16, 0);

     }
     if (s->ss_v) {
         // BUG https://code.google.com/p/webm/issues/detail?id=820

         mv.y = av_clip(in_mv->y, -(y + ph - py + 4) << 4, (s->rows * 4 - y + py + 3) << 4);

         my = scale_mv(mv.y, 1) + (scale_mv(y * 16, 1) & ~15) + (scale_mv(y * 32, 1) & 15);

     } else {

         mv.y = av_clip(in_mv->y, -(y + ph - py + 4) << 3, (s->rows * 8 - y + py + 3) << 3);

         my = scale_mv(mv.y << 1, 1) + scale_mv(y * 16, 1);

     }
 #undef scale_mv

     y = my >> 4;
     x = mx >> 4;

     ref_u += y * src_stride_u + x * bytesperpixel;
     ref_v += y * src_stride_v + x * bytesperpixel;

     mx &= 15;
     my &= 15;
     refbw_m1 = ((bw - 1) * step[0] + mx) >> 4;
     refbh_m1 = ((bh - 1) * step[1] + my) >> 4;
     // FIXME bilinear filter only needs 0/1 pixels, not 3/4
     // we use +7 because the last 7 pixels of each sbrow can be changed in
     // the longest loopfilter of the next sbrow

     th = (y + refbh_m1 + 4 + 7) >> (6 - s->ss_v);

     ff_thread_await_progress(ref_frame, FFMAX(th, 0), 0);
     if (x < 3 || y < 3 || x + 4 >= w - refbw_m1 || y + 4 >= h - refbh_m1) {
         s->vdsp.emulated_edge_mc(s->edge_emu_buffer,

                                  ref_u - 3 * src_stride_u - 3 * bytesperpixel,
                                  288, src_stride_u,

                                  refbw_m1 + 8, refbh_m1 + 8,
                                  x - 3, y - 3, w, h);

         ref_u = s->edge_emu_buffer + 3 * 288 + 3 * bytesperpixel;
         smc(dst_u, dst_stride, ref_u, 288, bh, mx, my, step[0], step[1]);

 
         s->vdsp.emulated_edge_mc(s->edge_emu_buffer,

                                  ref_v - 3 * src_stride_v - 3 * bytesperpixel,
                                  288, src_stride_v,

                                  refbw_m1 + 8, refbh_m1 + 8,
                                  x - 3, y - 3, w, h);

         ref_v = s->edge_emu_buffer + 3 * 288 + 3 * bytesperpixel;
         smc(dst_v, dst_stride, ref_v, 288, bh, mx, my, step[0], step[1]);

     } else {
         smc(dst_u, dst_stride, ref_u, src_stride_u, bh, mx, my, step[0], step[1]);
         smc(dst_v, dst_stride, ref_v, src_stride_v, bh, mx, my, step[0], step[1]);
     }
 }
 

 #define mc_luma_dir(s, mc, dst, dst_ls, src, src_ls, tref, row, col, mv, \
                     px, py, pw, ph, bw, bh, w, h, i) \

     mc_luma_scaled(s, s->dsp.s##mc, dst, dst_ls, src, src_ls, tref, row, col, \

                    mv, px, py, pw, ph, bw, bh, w, h, bytesperpixel, \

                    s->mvscale[b->ref[i]], s->mvstep[b->ref[i]])

 #define mc_chroma_dir(s, mc, dstu, dstv, dst_ls, srcu, srcu_ls, srcv, srcv_ls, tref, \

                       row, col, mv, px, py, pw, ph, bw, bh, w, h, i) \

     mc_chroma_scaled(s, s->dsp.s##mc, dstu, dstv, dst_ls, srcu, srcu_ls, srcv, srcv_ls, tref, \

                      row, col, mv, px, py, pw, ph, bw, bh, w, h, bytesperpixel, \

                      s->mvscale[b->ref[i]], s->mvstep[b->ref[i]])

 #define SCALED 1

 #define FN(x) x##_scaled_8bpp
 #define BYTES_PER_PIXEL 1
 #include "vp9_mc_template.c"
 #undef FN
 #undef BYTES_PER_PIXEL
 #define FN(x) x##_scaled_16bpp
 #define BYTES_PER_PIXEL 2

 #include "vp9_mc_template.c"
 #undef mc_luma_dir
 #undef mc_chroma_dir
 #undef FN

 #undef BYTES_PER_PIXEL

 #undef SCALED

 
 static av_always_inline void mc_luma_unscaled(VP9Context *s, vp9_mc_func (*mc)[2],
                                               uint8_t *dst, ptrdiff_t dst_stride,
                                               const uint8_t *ref, ptrdiff_t ref_stride,
                                               ThreadFrame *ref_frame,
                                               ptrdiff_t y, ptrdiff_t x, const VP56mv *mv,

                                               int bw, int bh, int w, int h, int bytesperpixel)

 {

     int mx = mv->x, my = mv->y, th;

 
     y += my >> 3;
     x += mx >> 3;

     ref += y * ref_stride + x * bytesperpixel;

     mx &= 7;
     my &= 7;
     // FIXME bilinear filter only needs 0/1 pixels, not 3/4

     // we use +7 because the last 7 pixels of each sbrow can be changed in
     // the longest loopfilter of the next sbrow
     th = (y + bh + 4 * !!my + 7) >> 6;
     ff_thread_await_progress(ref_frame, FFMAX(th, 0), 0);

     if (x < !!mx * 3 || y < !!my * 3 ||
         x + !!mx * 4 > w - bw || y + !!my * 4 > h - bh) {

         s->vdsp.emulated_edge_mc(s->edge_emu_buffer,

                                  ref - !!my * 3 * ref_stride - !!mx * 3 * bytesperpixel,
                                  160, ref_stride,

                                  bw + !!mx * 7, bh + !!my * 7,
                                  x - !!mx * 3, y - !!my * 3, w, h);

         ref = s->edge_emu_buffer + !!my * 3 * 160 + !!mx * 3 * bytesperpixel;
         ref_stride = 160;

     }
     mc[!!mx][!!my](dst, dst_stride, ref, ref_stride, bh, mx << 1, my << 1);
 }
 

 static av_always_inline void mc_chroma_unscaled(VP9Context *s, vp9_mc_func (*mc)[2],
                                                 uint8_t *dst_u, uint8_t *dst_v,
                                                 ptrdiff_t dst_stride,
                                                 const uint8_t *ref_u, ptrdiff_t src_stride_u,
                                                 const uint8_t *ref_v, ptrdiff_t src_stride_v,
                                                 ThreadFrame *ref_frame,
                                                 ptrdiff_t y, ptrdiff_t x, const VP56mv *mv,

                                                 int bw, int bh, int w, int h, int bytesperpixel)

 {

     int mx = mv->x << !s->ss_h, my = mv->y << !s->ss_v, th;

 
     y += my >> 4;
     x += mx >> 4;

     ref_u += y * src_stride_u + x * bytesperpixel;
     ref_v += y * src_stride_v + x * bytesperpixel;

     mx &= 15;
     my &= 15;
     // FIXME bilinear filter only needs 0/1 pixels, not 3/4

     // we use +7 because the last 7 pixels of each sbrow can be changed in
     // the longest loopfilter of the next sbrow

     th = (y + bh + 4 * !!my + 7) >> (6 - s->ss_v);

     ff_thread_await_progress(ref_frame, FFMAX(th, 0), 0);

     if (x < !!mx * 3 || y < !!my * 3 ||
         x + !!mx * 4 > w - bw || y + !!my * 4 > h - bh) {

         s->vdsp.emulated_edge_mc(s->edge_emu_buffer,

                                  ref_u - !!my * 3 * src_stride_u - !!mx * 3 * bytesperpixel,
                                  160, src_stride_u,

                                  bw + !!mx * 7, bh + !!my * 7,
                                  x - !!mx * 3, y - !!my * 3, w, h);

         ref_u = s->edge_emu_buffer + !!my * 3 * 160 + !!mx * 3 * bytesperpixel;
         mc[!!mx][!!my](dst_u, dst_stride, ref_u, 160, bh, mx, my);

         s->vdsp.emulated_edge_mc(s->edge_emu_buffer,

                                  ref_v - !!my * 3 * src_stride_v - !!mx * 3 * bytesperpixel,
                                  160, src_stride_v,

                                  bw + !!mx * 7, bh + !!my * 7,
                                  x - !!mx * 3, y - !!my * 3, w, h);

         ref_v = s->edge_emu_buffer + !!my * 3 * 160 + !!mx * 3 * bytesperpixel;
         mc[!!mx][!!my](dst_v, dst_stride, ref_v, 160, bh, mx, my);

     } else {
         mc[!!mx][!!my](dst_u, dst_stride, ref_u, src_stride_u, bh, mx, my);
         mc[!!mx][!!my](dst_v, dst_stride, ref_v, src_stride_v, bh, mx, my);
     }
 }
 

 #define mc_luma_dir(s, mc, dst, dst_ls, src, src_ls, tref, row, col, mv, \
                     px, py, pw, ph, bw, bh, w, h, i) \

     mc_luma_unscaled(s, s->dsp.mc, dst, dst_ls, src, src_ls, tref, row, col, \

                      mv, bw, bh, w, h, bytesperpixel)

 #define mc_chroma_dir(s, mc, dstu, dstv, dst_ls, srcu, srcu_ls, srcv, srcv_ls, tref, \

                       row, col, mv, px, py, pw, ph, bw, bh, w, h, i) \

     mc_chroma_unscaled(s, s->dsp.mc, dstu, dstv, dst_ls, srcu, srcu_ls, srcv, srcv_ls, tref, \

                        row, col, mv, bw, bh, w, h, bytesperpixel)

 #define SCALED 0

 #define FN(x) x##_8bpp
 #define BYTES_PER_PIXEL 1
 #include "vp9_mc_template.c"
 #undef FN
 #undef BYTES_PER_PIXEL
 #define FN(x) x##_16bpp
 #define BYTES_PER_PIXEL 2

 #include "vp9_mc_template.c"
 #undef mc_luma_dir_dir
 #undef mc_chroma_dir_dir
 #undef FN

 #undef BYTES_PER_PIXEL

 #undef SCALED

 static av_always_inline void inter_recon(AVCodecContext *ctx, int bytesperpixel)

 {
     VP9Context *s = ctx->priv_data;

     VP9Block *b = s->b;

     int row = s->row, col = s->col;

     if (s->mvscale[b->ref[0]][0] || (b->comp && s->mvscale[b->ref[1]][0])) {

         if (bytesperpixel == 1) {
             inter_pred_scaled_8bpp(ctx);
         } else {
             inter_pred_scaled_16bpp(ctx);
         }

     } else {

         if (bytesperpixel == 1) {
             inter_pred_8bpp(ctx);
         } else {
             inter_pred_16bpp(ctx);
         }

     }
     if (!b->skip) {

         /* mostly copied intra_recon() */

 
         int w4 = bwh_tab[1][b->bs][0] << 1, step1d = 1 << b->tx, n;
         int h4 = bwh_tab[1][b->bs][1] << 1, x, y, step = 1 << (b->tx * 2);
         int end_x = FFMIN(2 * (s->cols - col), w4);
         int end_y = FFMIN(2 * (s->rows - row), h4);
         int tx = 4 * s->lossless + b->tx, uvtx = b->uvtx + 4 * s->lossless;
         int uvstep1d = 1 << b->uvtx, p;

         uint8_t *dst = s->dst[0];

 
         // y itxfm add
         for (n = 0, y = 0; y < end_y; y += step1d) {
             uint8_t *ptr = dst;

             for (x = 0; x < end_x; x += step1d,
                  ptr += 4 * step1d * bytesperpixel, n += step) {

                 int eob = b->tx > TX_8X8 ? AV_RN16A(&s->eob[n]) : s->eob[n];
 
                 if (eob)

                     s->dsp.itxfm_add[tx][DCT_DCT](ptr, s->y_stride,

                                                   s->block + 16 * n * bytesperpixel, eob);

             }

             dst += 4 * s->y_stride * step1d;

         }
 
         // uv itxfm add

         end_x >>= s->ss_h;
         end_y >>= s->ss_v;

         step = 1 << (b->uvtx * 2);
         for (p = 0; p < 2; p++) {

             dst = s->dst[p + 1];

             for (n = 0, y = 0; y < end_y; y += uvstep1d) {
                 uint8_t *ptr = dst;

                 for (x = 0; x < end_x; x += uvstep1d,
                      ptr += 4 * uvstep1d * bytesperpixel, n += step) {

                     int eob = b->uvtx > TX_8X8 ? AV_RN16A(&s->uveob[p][n]) : s->uveob[p][n];
 
                     if (eob)

                         s->dsp.itxfm_add[uvtx][DCT_DCT](ptr, s->uv_stride,

                                                         s->uvblock[p] + 16 * n * bytesperpixel, eob);

                 }

                 dst += 4 * uvstep1d * s->uv_stride;

             }
         }
     }
 }
 

 static void inter_recon_8bpp(AVCodecContext *ctx)
 {
     inter_recon(ctx, 1);
 }
 
 static void inter_recon_16bpp(AVCodecContext *ctx)
 {
     inter_recon(ctx, 2);
 }
 

 static av_always_inline void mask_edges(uint8_t (*mask)[8][4], int ss_h, int ss_v,

                                         int row_and_7, int col_and_7,
                                         int w, int h, int col_end, int row_end,
                                         enum TxfmMode tx, int skip_inter)
 {

     static const unsigned wide_filter_col_mask[2] = { 0x11, 0x01 };
     static const unsigned wide_filter_row_mask[2] = { 0x03, 0x07 };
 

     // FIXME I'm pretty sure all loops can be replaced by a single LUT if
     // we make VP9Filter.mask uint64_t (i.e. row/col all single variable)
     // and make the LUT 5-indexed (bl, bp, is_uv, tx and row/col), and then
     // use row_and_7/col_and_7 as shifts (1*col_and_7+8*row_and_7)
 
     // the intended behaviour of the vp9 loopfilter is to work on 8-pixel
     // edges. This means that for UV, we work on two subsampled blocks at
     // a time, and we only use the topleft block's mode information to set
     // things like block strength. Thus, for any block size smaller than
     // 16x16, ignore the odd portion of the block.

     if (tx == TX_4X4 && (ss_v | ss_h)) {
         if (h == ss_v) {

             if (row_and_7 & 1)
                 return;
             if (!row_end)
                 h += 1;
         }

         if (w == ss_h) {

             if (col_and_7 & 1)
                 return;
             if (!col_end)
                 w += 1;
         }
     }
 
     if (tx == TX_4X4 && !skip_inter) {
         int t = 1 << col_and_7, m_col = (t << w) - t, y;
         // on 32-px edges, use the 8-px wide loopfilter; else, use 4-px wide

         int m_row_8 = m_col & wide_filter_col_mask[ss_h], m_row_4 = m_col - m_row_8;
 
         for (y = row_and_7; y < h + row_and_7; y++) {
             int col_mask_id = 2 - !(y & wide_filter_row_mask[ss_v]);
 
             mask[0][y][1] |= m_row_8;
             mask[0][y][2] |= m_row_4;
             // for odd lines, if the odd col is not being filtered,
             // skip odd row also:
             // .---. <-- a
             // |   |
             // |___| <-- b
             // ^   ^
             // c   d
             //
             // if a/c are even row/col and b/d are odd, and d is skipped,
             // e.g. right edge of size-66x66.webm, then skip b also (bug)
             if ((ss_h & ss_v) && (col_end & 1) && (y & 1)) {
                 mask[1][y][col_mask_id] |= (t << (w - 1)) - t;
             } else {
                 mask[1][y][col_mask_id] |= m_col;

             }

             if (!ss_h)

                 mask[0][y][3] |= m_col;

             if (!ss_v) {
                 if (ss_h && (col_end & 1))
                     mask[1][y][3] |= (t << (w - 1)) - t;
                 else
                     mask[1][y][3] |= m_col;
             }

         }
     } else {
         int y, t = 1 << col_and_7, m_col = (t << w) - t;
 
         if (!skip_inter) {
             int mask_id = (tx == TX_8X8);
             static const unsigned masks[4] = { 0xff, 0x55, 0x11, 0x01 };

             int l2 = tx + ss_h - 1, step1d;

             int m_row = m_col & masks[l2];
 
             // at odd UV col/row edges tx16/tx32 loopfilter edges, force
             // 8wd loopfilter to prevent going off the visible edge.

             if (ss_h && tx > TX_8X8 && (w ^ (w - 1)) == 1) {

                 int m_row_16 = ((t << (w - 1)) - t) & masks[l2];
                 int m_row_8 = m_row - m_row_16;
 
                 for (y = row_and_7; y < h + row_and_7; y++) {

                     mask[0][y][0] |= m_row_16;
                     mask[0][y][1] |= m_row_8;

                 }
             } else {
                 for (y = row_and_7; y < h + row_and_7; y++)

                     mask[0][y][mask_id] |= m_row;

             }
 

             l2 = tx + ss_v - 1;
             step1d = 1 << l2;
             if (ss_v && tx > TX_8X8 && (h ^ (h - 1)) == 1) {

                 for (y = row_and_7; y < h + row_and_7 - 1; y += step1d)

                     mask[1][y][0] |= m_col;

                 if (y - row_and_7 == h - 1)

                     mask[1][y][1] |= m_col;

             } else {
                 for (y = row_and_7; y < h + row_and_7; y += step1d)

                     mask[1][y][mask_id] |= m_col;

             }
         } else if (tx != TX_4X4) {
             int mask_id;
 

             mask_id = (tx == TX_8X8) || (h == ss_v);

             mask[1][row_and_7][mask_id] |= m_col;

             mask_id = (tx == TX_8X8) || (w == ss_h);

             for (y = row_and_7; y < h + row_and_7; y++)

                 mask[0][y][mask_id] |= t;

         } else {

             int t8 = t & wide_filter_col_mask[ss_h], t4 = t - t8;

 
             for (y = row_and_7; y < h + row_and_7; y++) {

                 mask[0][y][2] |= t4;
                 mask[0][y][1] |= t8;

             }

             mask[1][row_and_7][2 - !(row_and_7 & wide_filter_row_mask[ss_v])] |= m_col;

         }
     }
 }
 

 static void decode_b(AVCodecContext *ctx, int row, int col,
                      struct VP9Filter *lflvl, ptrdiff_t yoff, ptrdiff_t uvoff,
                      enum BlockLevel bl, enum BlockPartition bp)

 {
     VP9Context *s = ctx->priv_data;

     VP9Block *b = s->b;

     enum BlockSize bs = bl * 3 + bp;

     int bytesperpixel = s->bytesperpixel;

     int w4 = bwh_tab[1][bs][0], h4 = bwh_tab[1][bs][1], lvl;

     int emu[2];

     AVFrame *f = s->frames[CUR_FRAME].tf.f;

     s->row = row;
     s->row7 = row & 7;
     s->col = col;
     s->col7 = col & 7;

     s->min_mv.x = -(128 + col * 64);
     s->min_mv.y = -(128 + row * 64);
     s->max_mv.x = 128 + (s->cols - col - w4) * 64;
     s->max_mv.y = 128 + (s->rows - row - h4) * 64;

     if (s->pass < 2) {
         b->bs = bs;
         b->bl = bl;
         b->bp = bp;
         decode_mode(ctx);

         b->uvtx = b->tx - ((s->ss_h && w4 * 2 == (1 << b->tx)) ||
                            (s->ss_v && h4 * 2 == (1 << b->tx)));

 
         if (!b->skip) {

             int has_coeffs;
 

             if (bytesperpixel == 1) {

                 has_coeffs = decode_coeffs_8bpp(ctx);

             } else {

                 has_coeffs = decode_coeffs_16bpp(ctx);
             }
             if (!has_coeffs && b->bs <= BS_8x8 && !b->intra) {
                 b->skip = 1;
                 memset(&s->above_skip_ctx[col], 1, w4);
                 memset(&s->left_skip_ctx[s->row7], 1, h4);

             }

         } else {

             int row7 = s->row7;
 
 #define SPLAT_ZERO_CTX(v, n) \
     switch (n) { \
     case 1:  v = 0;          break; \
     case 2:  AV_ZERO16(&v);  break; \
     case 4:  AV_ZERO32(&v);  break; \
     case 8:  AV_ZERO64(&v);  break; \
     case 16: AV_ZERO128(&v); break; \
     }

 #define SPLAT_ZERO_YUV(dir, var, off, n, dir2) \

     do { \
         SPLAT_ZERO_CTX(s->dir##_y_##var[off * 2], n * 2); \

         if (s->ss_##dir2) { \
             SPLAT_ZERO_CTX(s->dir##_uv_##var[0][off], n); \
             SPLAT_ZERO_CTX(s->dir##_uv_##var[1][off], n); \
         } else { \
             SPLAT_ZERO_CTX(s->dir##_uv_##var[0][off * 2], n * 2); \
             SPLAT_ZERO_CTX(s->dir##_uv_##var[1][off * 2], n * 2); \
         } \

     } while (0)

             switch (w4) {

             case 1: SPLAT_ZERO_YUV(above, nnz_ctx, col, 1, h); break;
             case 2: SPLAT_ZERO_YUV(above, nnz_ctx, col, 2, h); break;
             case 4: SPLAT_ZERO_YUV(above, nnz_ctx, col, 4, h); break;
             case 8: SPLAT_ZERO_YUV(above, nnz_ctx, col, 8, h); break;

             }
             switch (h4) {

             case 1: SPLAT_ZERO_YUV(left, nnz_ctx, row7, 1, v); break;
             case 2: SPLAT_ZERO_YUV(left, nnz_ctx, row7, 2, v); break;
             case 4: SPLAT_ZERO_YUV(left, nnz_ctx, row7, 4, v); break;
             case 8: SPLAT_ZERO_YUV(left, nnz_ctx, row7, 8, v); break;

             }
         }
         if (s->pass == 1) {
             s->b++;

             s->block += w4 * h4 * 64 * bytesperpixel;
             s->uvblock[0] += w4 * h4 * 64 * bytesperpixel >> (s->ss_h + s->ss_v);
             s->uvblock[1] += w4 * h4 * 64 * bytesperpixel >> (s->ss_h + s->ss_v);

             s->eob += 4 * w4 * h4;

             s->uveob[0] += 4 * w4 * h4 >> (s->ss_h + s->ss_v);
             s->uveob[1] += 4 * w4 * h4 >> (s->ss_h + s->ss_v);

             return;

         }
     }
 
     // emulated overhangs if the stride of the target buffer can't hold. This

     // makes it possible to support emu-edge and so on even if we have large block

     // overhangs

     emu[0] = (col + w4) * 8 > f->linesize[0] ||

              (row + h4) > s->rows;

     emu[1] = (col + w4) * 4 > f->linesize[1] ||

              (row + h4) > s->rows;

     if (emu[0]) {

         s->dst[0] = s->tmp_y;

         s->y_stride = 128;

     } else {

         s->dst[0] = f->data[0] + yoff;
         s->y_stride = f->linesize[0];

     }
     if (emu[1]) {

         s->dst[1] = s->tmp_uv[0];
         s->dst[2] = s->tmp_uv[1];

         s->uv_stride = 128;

     } else {

         s->dst[1] = f->data[1] + uvoff;
         s->dst[2] = f->data[2] + uvoff;
         s->uv_stride = f->linesize[1];

     }
     if (b->intra) {

         if (s->bpp > 8) {
             intra_recon_16bpp(ctx, yoff, uvoff);
         } else {
             intra_recon_8bpp(ctx, yoff, uvoff);
         }

     } else {

         if (s->bpp > 8) {
             inter_recon_16bpp(ctx);
         } else {
             inter_recon_8bpp(ctx);
         }

     }
     if (emu[0]) {
         int w = FFMIN(s->cols - col, w4) * 8, h = FFMIN(s->rows - row, h4) * 8, n, o = 0;
 
         for (n = 0; o < w; n++) {
             int bw = 64 >> n;
 
             av_assert2(n <= 4);
             if (w & bw) {

                 s->dsp.mc[n][0][0][0][0](f->data[0] + yoff + o, f->linesize[0],

                                          s->tmp_y + o, 128, h, 0, 0);
                 o += bw * bytesperpixel;

             }
         }
     }
     if (emu[1]) {

         int w = FFMIN(s->cols - col, w4) * 8 >> s->ss_h;
         int h = FFMIN(s->rows - row, h4) * 8 >> s->ss_v, n, o = 0;

         for (n = s->ss_h; o < w; n++) {

             int bw = 64 >> n;
 
             av_assert2(n <= 4);
             if (w & bw) {

                 s->dsp.mc[n][0][0][0][0](f->data[1] + uvoff + o, f->linesize[1],

                                          s->tmp_uv[0] + o, 128, h, 0, 0);

                 s->dsp.mc[n][0][0][0][0](f->data[2] + uvoff + o, f->linesize[2],

                                          s->tmp_uv[1] + o, 128, h, 0, 0);
                 o += bw * bytesperpixel;

             }
         }
     }
 
     // pick filter level and find edges to apply filter to
     if (s->filter.level &&
         (lvl = s->segmentation.feat[b->seg_id].lflvl[b->intra ? 0 : b->ref[0] + 1]
                                                     [b->mode[3] != ZEROMV]) > 0) {
         int x_end = FFMIN(s->cols - col, w4), y_end = FFMIN(s->rows - row, h4);

         int skip_inter = !b->intra && b->skip, col7 = s->col7, row7 = s->row7;

         setctx_2d(&lflvl->level[row7 * 8 + col7], w4, h4, 8, lvl);

         mask_edges(lflvl->mask[0], 0, 0, row7, col7, x_end, y_end, 0, 0, b->tx, skip_inter);

         if (s->ss_h || s->ss_v)

             mask_edges(lflvl->mask[1], s->ss_h, s->ss_v, row7, col7, x_end, y_end,

                        s->cols & 1 && col + w4 >= s->cols ? s->cols & 7 : 0,
                        s->rows & 1 && row + h4 >= s->rows ? s->rows & 7 : 0,
                        b->uvtx, skip_inter);

 
         if (!s->filter.lim_lut[lvl]) {
             int sharp = s->filter.sharpness;
             int limit = lvl;
 
             if (sharp > 0) {
                 limit >>= (sharp + 3) >> 2;
                 limit = FFMIN(limit, 9 - sharp);
             }
             limit = FFMAX(limit, 1);
 
             s->filter.lim_lut[lvl] = limit;
             s->filter.mblim_lut[lvl] = 2 * (lvl + 2) + limit;
         }
     }
 

     if (s->pass == 2) {
         s->b++;

         s->block += w4 * h4 * 64 * bytesperpixel;
         s->uvblock[0] += w4 * h4 * 64 * bytesperpixel >> (s->ss_v + s->ss_h);
         s->uvblock[1] += w4 * h4 * 64 * bytesperpixel >> (s->ss_v + s->ss_h);

         s->eob += 4 * w4 * h4;

         s->uveob[0] += 4 * w4 * h4 >> (s->ss_v + s->ss_h);
         s->uveob[1] += 4 * w4 * h4 >> (s->ss_v + s->ss_h);

     }

 }
 

 static void decode_sb(AVCodecContext *ctx, int row, int col, struct VP9Filter *lflvl,
                       ptrdiff_t yoff, ptrdiff_t uvoff, enum BlockLevel bl)

 {
     VP9Context *s = ctx->priv_data;
     int c = ((s->above_partition_ctx[col] >> (3 - bl)) & 1) |

             (((s->left_partition_ctx[row & 0x7] >> (3 - bl)) & 1) << 1);

     const uint8_t *p = s->keyframe || s->intraonly ? vp9_default_kf_partition_probs[bl][c] :
                                                      s->prob.p.partition[bl][c];

     enum BlockPartition bp;
     ptrdiff_t hbs = 4 >> bl;

     AVFrame *f = s->frames[CUR_FRAME].tf.f;
     ptrdiff_t y_stride = f->linesize[0], uv_stride = f->linesize[1];

     int bytesperpixel = s->bytesperpixel;

 
     if (bl == BL_8X8) {
         bp = vp8_rac_get_tree(&s->c, vp9_partition_tree, p);

         decode_b(ctx, row, col, lflvl, yoff, uvoff, bl, bp);

     } else if (col + hbs < s->cols) { // FIXME why not <=?
         if (row + hbs < s->rows) { // FIXME why not <=?

             bp = vp8_rac_get_tree(&s->c, vp9_partition_tree, p);
             switch (bp) {
             case PARTITION_NONE:

                 decode_b(ctx, row, col, lflvl, yoff, uvoff, bl, bp);

                 break;
             case PARTITION_H:

                 decode_b(ctx, row, col, lflvl, yoff, uvoff, bl, bp);
                 yoff  += hbs * 8 * y_stride;

                 uvoff += hbs * 8 * uv_stride >> s->ss_v;

                 decode_b(ctx, row + hbs, col, lflvl, yoff, uvoff, bl, bp);

                 break;
             case PARTITION_V:

                 decode_b(ctx, row, col, lflvl, yoff, uvoff, bl, bp);

                 yoff  += hbs * 8 * bytesperpixel;
                 uvoff += hbs * 8 * bytesperpixel >> s->ss_h;

                 decode_b(ctx, row, col + hbs, lflvl, yoff, uvoff, bl, bp);

                 break;
             case PARTITION_SPLIT:

                 decode_sb(ctx, row, col, lflvl, yoff, uvoff, bl + 1);
                 decode_sb(ctx, row, col + hbs, lflvl,

                           yoff + 8 * hbs * bytesperpixel,
                           uvoff + (8 * hbs * bytesperpixel >> s->ss_h), bl + 1);

                 yoff  += hbs * 8 * y_stride;

                 uvoff += hbs * 8 * uv_stride >> s->ss_v;

                 decode_sb(ctx, row + hbs, col, lflvl, yoff, uvoff, bl + 1);
                 decode_sb(ctx, row + hbs, col + hbs, lflvl,

                           yoff + 8 * hbs * bytesperpixel,
                           uvoff + (8 * hbs * bytesperpixel >> s->ss_h), bl + 1);

                 break;

             default:
                 av_assert0(0);

             }
         } else if (vp56_rac_get_prob_branchy(&s->c, p[1])) {
             bp = PARTITION_SPLIT;

             decode_sb(ctx, row, col, lflvl, yoff, uvoff, bl + 1);
             decode_sb(ctx, row, col + hbs, lflvl,

                       yoff + 8 * hbs * bytesperpixel,
                       uvoff + (8 * hbs * bytesperpixel >> s->ss_h), bl + 1);

         } else {
             bp = PARTITION_H;

             decode_b(ctx, row, col, lflvl, yoff, uvoff, bl, bp);

         }

     } else if (row + hbs < s->rows) { // FIXME why not <=?

         if (vp56_rac_get_prob_branchy(&s->c, p[2])) {
             bp = PARTITION_SPLIT;

             decode_sb(ctx, row, col, lflvl, yoff, uvoff, bl + 1);
             yoff  += hbs * 8 * y_stride;

             uvoff += hbs * 8 * uv_stride >> s->ss_v;

             decode_sb(ctx, row + hbs, col, lflvl, yoff, uvoff, bl + 1);

         } else {
             bp = PARTITION_V;

             decode_b(ctx, row, col, lflvl, yoff, uvoff, bl, bp);

         }
     } else {
         bp = PARTITION_SPLIT;

         decode_sb(ctx, row, col, lflvl, yoff, uvoff, bl + 1);

     }
     s->counts.partition[bl][c][bp]++;
 }
 

 static void decode_sb_mem(AVCodecContext *ctx, int row, int col, struct VP9Filter *lflvl,
                           ptrdiff_t yoff, ptrdiff_t uvoff, enum BlockLevel bl)

 {
     VP9Context *s = ctx->priv_data;
     VP9Block *b = s->b;
     ptrdiff_t hbs = 4 >> bl;
     AVFrame *f = s->frames[CUR_FRAME].tf.f;
     ptrdiff_t y_stride = f->linesize[0], uv_stride = f->linesize[1];

     int bytesperpixel = s->bytesperpixel;

 
     if (bl == BL_8X8) {
         av_assert2(b->bl == BL_8X8);

         decode_b(ctx, row, col, lflvl, yoff, uvoff, b->bl, b->bp);

     } else if (s->b->bl == bl) {

         decode_b(ctx, row, col, lflvl, yoff, uvoff, b->bl, b->bp);

         if (b->bp == PARTITION_H && row + hbs < s->rows) {
             yoff  += hbs * 8 * y_stride;

             uvoff += hbs * 8 * uv_stride >> s->ss_v;

             decode_b(ctx, row + hbs, col, lflvl, yoff, uvoff, b->bl, b->bp);

         } else if (b->bp == PARTITION_V && col + hbs < s->cols) {

             yoff  += hbs * 8 * bytesperpixel;
             uvoff += hbs * 8 * bytesperpixel >> s->ss_h;

             decode_b(ctx, row, col + hbs, lflvl, yoff, uvoff, b->bl, b->bp);

         }
     } else {

         decode_sb_mem(ctx, row, col, lflvl, yoff, uvoff, bl + 1);

         if (col + hbs < s->cols) { // FIXME why not <=?
             if (row + hbs < s->rows) {

                 decode_sb_mem(ctx, row, col + hbs, lflvl, yoff + 8 * hbs * bytesperpixel,
                               uvoff + (8 * hbs * bytesperpixel >> s->ss_h), bl + 1);

                 yoff  += hbs * 8 * y_stride;

                 uvoff += hbs * 8 * uv_stride >> s->ss_v;

                 decode_sb_mem(ctx, row + hbs, col, lflvl, yoff, uvoff, bl + 1);
                 decode_sb_mem(ctx, row + hbs, col + hbs, lflvl,

                               yoff + 8 * hbs * bytesperpixel,
                               uvoff + (8 * hbs * bytesperpixel >> s->ss_h), bl + 1);

             } else {

                 yoff  += hbs * 8 * bytesperpixel;
                 uvoff += hbs * 8 * bytesperpixel >> s->ss_h;

                 decode_sb_mem(ctx, row, col + hbs, lflvl, yoff, uvoff, bl + 1);

             }
         } else if (row + hbs < s->rows) {
             yoff  += hbs * 8 * y_stride;

             uvoff += hbs * 8 * uv_stride >> s->ss_v;

             decode_sb_mem(ctx, row + hbs, col, lflvl, yoff, uvoff, bl + 1);

         }
     }
 }
 

 static av_always_inline void filter_plane_cols(VP9Context *s, int col, int ss_h, int ss_v,

                                                uint8_t *lvl, uint8_t (*mask)[4],
                                                uint8_t *dst, ptrdiff_t ls)

 {

     int y, x, bytesperpixel = s->bytesperpixel;

     // filter edges between columns (e.g. block1 | block2)

     for (y = 0; y < 8; y += 2 << ss_v, dst += 16 * ls, lvl += 16 << ss_v) {
         uint8_t *ptr = dst, *l = lvl, *hmask1 = mask[y], *hmask2 = mask[y + 1 + ss_v];

         unsigned hm1 = hmask1[0] | hmask1[1] | hmask1[2], hm13 = hmask1[3];
         unsigned hm2 = hmask2[1] | hmask2[2], hm23 = hmask2[3];
         unsigned hm = hm1 | hm2 | hm13 | hm23;
 

         for (x = 1; hm & ~(x - 1); x <<= 1, ptr += 8 * bytesperpixel >> ss_h) {

             if (col || x > 1) {
                 if (hm1 & x) {
                     int L = *l, H = L >> 4;
                     int E = s->filter.mblim_lut[L], I = s->filter.lim_lut[L];

 
                     if (hmask1[0] & x) {
                         if (hmask2[0] & x) {

                             av_assert2(l[8 << ss_v] == L);

                             s->dsp.loop_filter_16[0](ptr, ls, E, I, H);

                         } else {

                             s->dsp.loop_filter_8[2][0](ptr, ls, E, I, H);

                         }
                     } else if (hm2 & x) {

                         L = l[8 << ss_v];

                         H |= (L >> 4) << 8;
                         E |= s->filter.mblim_lut[L] << 8;
                         I |= s->filter.lim_lut[L] << 8;
                         s->dsp.loop_filter_mix2[!!(hmask1[1] & x)]
                                                [!!(hmask2[1] & x)]

                                                [0](ptr, ls, E, I, H);

                     } else {
                         s->dsp.loop_filter_8[!!(hmask1[1] & x)]

                                             [0](ptr, ls, E, I, H);

                     }

                 } else if (hm2 & x) {

                     int L = l[8 << ss_v], H = L >> 4;

                     int E = s->filter.mblim_lut[L], I = s->filter.lim_lut[L];

 
                     s->dsp.loop_filter_8[!!(hmask2[1] & x)]

                                         [0](ptr + 8 * ls, ls, E, I, H);

                 }
             }

             if (ss_h) {

                 if (x & 0xAA)
                     l += 2;
             } else {
                 if (hm13 & x) {
                     int L = *l, H = L >> 4;
                     int E = s->filter.mblim_lut[L], I = s->filter.lim_lut[L];

                     if (hm23 & x) {

                         L = l[8 << ss_v];

                         H |= (L >> 4) << 8;
                         E |= s->filter.mblim_lut[L] << 8;
                         I |= s->filter.lim_lut[L] << 8;

                         s->dsp.loop_filter_mix2[0][0][0](ptr + 4 * bytesperpixel, ls, E, I, H);

                     } else {

                         s->dsp.loop_filter_8[0][0](ptr + 4 * bytesperpixel, ls, E, I, H);

                     }
                 } else if (hm23 & x) {

                     int L = l[8 << ss_v], H = L >> 4;

                     int E = s->filter.mblim_lut[L], I = s->filter.lim_lut[L];

                     s->dsp.loop_filter_8[0][0](ptr + 8 * ls + 4 * bytesperpixel, ls, E, I, H);

                 }
                 l++;

             }
         }
     }

 }
 

 static av_always_inline void filter_plane_rows(VP9Context *s, int row, int ss_h, int ss_v,

                                                uint8_t *lvl, uint8_t (*mask)[4],
                                                uint8_t *dst, ptrdiff_t ls)
 {

     int y, x, bytesperpixel = s->bytesperpixel;

     //                                 block1
     // filter edges between rows (e.g. ------)
     //                                 block2

     for (y = 0; y < 8; y++, dst += 8 * ls >> ss_v) {

         uint8_t *ptr = dst, *l = lvl, *vmask = mask[y];

         unsigned vm = vmask[0] | vmask[1] | vmask[2], vm3 = vmask[3];
 

         for (x = 1; vm & ~(x - 1); x <<= (2 << ss_h), ptr += 16 * bytesperpixel, l += 2 << ss_h) {

             if (row || y) {
                 if (vm & x) {
                     int L = *l, H = L >> 4;
                     int E = s->filter.mblim_lut[L], I = s->filter.lim_lut[L];
 
                     if (vmask[0] & x) {

                         if (vmask[0] & (x << (1 + ss_h))) {
                             av_assert2(l[1 + ss_h] == L);

                             s->dsp.loop_filter_16[1](ptr, ls, E, I, H);

                         } else {

                             s->dsp.loop_filter_8[2][1](ptr, ls, E, I, H);

                         }

                     } else if (vm & (x << (1 + ss_h))) {
                         L = l[1 + ss_h];

                         H |= (L >> 4) << 8;
                         E |= s->filter.mblim_lut[L] << 8;
                         I |= s->filter.lim_lut[L] << 8;
                         s->dsp.loop_filter_mix2[!!(vmask[1] &  x)]

                                                [!!(vmask[1] & (x << (1 + ss_h)))]

                                                [1](ptr, ls, E, I, H);

                     } else {
                         s->dsp.loop_filter_8[!!(vmask[1] & x)]

                                             [1](ptr, ls, E, I, H);

                     }

                 } else if (vm & (x << (1 + ss_h))) {
                     int L = l[1 + ss_h], H = L >> 4;

                     int E = s->filter.mblim_lut[L], I = s->filter.lim_lut[L];
 

                     s->dsp.loop_filter_8[!!(vmask[1] & (x << (1 + ss_h)))]

                                         [1](ptr + 8 * bytesperpixel, ls, E, I, H);

                 }
             }

             if (!ss_v) {

                 if (vm3 & x) {
                     int L = *l, H = L >> 4;
                     int E = s->filter.mblim_lut[L], I = s->filter.lim_lut[L];

                     if (vm3 & (x << (1 + ss_h))) {
                         L = l[1 + ss_h];

                         H |= (L >> 4) << 8;
                         E |= s->filter.mblim_lut[L] << 8;
                         I |= s->filter.lim_lut[L] << 8;
                         s->dsp.loop_filter_mix2[0][0][1](ptr + ls * 4, ls, E, I, H);
                     } else {
                         s->dsp.loop_filter_8[0][1](ptr + ls * 4, ls, E, I, H);
                     }

                 } else if (vm3 & (x << (1 + ss_h))) {
                     int L = l[1 + ss_h], H = L >> 4;

                     int E = s->filter.mblim_lut[L], I = s->filter.lim_lut[L];

                     s->dsp.loop_filter_8[0][1](ptr + ls * 4 + 8 * bytesperpixel, ls, E, I, H);

                 }

             }
         }

         if (ss_v) {

             if (y & 1)
                 lvl += 16;
         } else {
             lvl += 8;
         }

     }

 }
 
 static void loopfilter_sb(AVCodecContext *ctx, struct VP9Filter *lflvl,
                           int row, int col, ptrdiff_t yoff, ptrdiff_t uvoff)
 {
     VP9Context *s = ctx->priv_data;
     AVFrame *f = s->frames[CUR_FRAME].tf.f;
     uint8_t *dst = f->data[0] + yoff;
     ptrdiff_t ls_y = f->linesize[0], ls_uv = f->linesize[1];

     uint8_t (*uv_masks)[8][4] = lflvl->mask[s->ss_h | s->ss_v];

     int p;

 
     // FIXME in how far can we interleave the v/h loopfilter calls? E.g.
     // if you think of them as acting on a 8x8 block max, we can interleave
     // each v/h within the single x loop, but that only works if we work on
     // 8 pixel blocks, and we won't always do that (we want at least 16px
     // to use SSE2 optimizations, perhaps 32 for AVX2)
 

     filter_plane_cols(s, col, 0, 0, lflvl->level, lflvl->mask[0][0], dst, ls_y);
     filter_plane_rows(s, row, 0, 0, lflvl->level, lflvl->mask[0][1], dst, ls_y);

 
     for (p = 0; p < 2; p++) {

         dst = f->data[1 + p] + uvoff;

         filter_plane_cols(s, col, s->ss_h, s->ss_v, lflvl->level, uv_masks[0], dst, ls_uv);
         filter_plane_rows(s, row, s->ss_h, s->ss_v, lflvl->level, uv_masks[1], dst, ls_uv);

     }
 }
 
 static void set_tile_offset(int *start, int *end, int idx, int log2_n, int n)
 {
     int sb_start = ( idx      * n) >> log2_n;
     int sb_end   = ((idx + 1) * n) >> log2_n;
     *start = FFMIN(sb_start, n) << 3;
     *end   = FFMIN(sb_end,   n) << 3;
 }
 
 static av_always_inline void adapt_prob(uint8_t *p, unsigned ct0, unsigned ct1,
                                         int max_count, int update_factor)
 {
     unsigned ct = ct0 + ct1, p2, p1;
 
     if (!ct)
         return;
 
     p1 = *p;
     p2 = ((ct0 << 8) + (ct >> 1)) / ct;
     p2 = av_clip(p2, 1, 255);
     ct = FFMIN(ct, max_count);
     update_factor = FASTDIV(update_factor * ct, max_count);
 
     // (p1 * (256 - update_factor) + p2 * update_factor + 128) >> 8
     *p = p1 + (((p2 - p1) * update_factor + 128) >> 8);
 }
 
 static void adapt_probs(VP9Context *s)
 {
     int i, j, k, l, m;
     prob_context *p = &s->prob_ctx[s->framectxid].p;
     int uf = (s->keyframe || s->intraonly || !s->last_keyframe) ? 112 : 128;
 
     // coefficients
     for (i = 0; i < 4; i++)
         for (j = 0; j < 2; j++)
             for (k = 0; k < 2; k++)
                 for (l = 0; l < 6; l++)
                     for (m = 0; m < 6; m++) {
                         uint8_t *pp = s->prob_ctx[s->framectxid].coef[i][j][k][l][m];
                         unsigned *e = s->counts.eob[i][j][k][l][m];
                         unsigned *c = s->counts.coef[i][j][k][l][m];
 
                         if (l == 0 && m >= 3) // dc only has 3 pt
                             break;
 
                         adapt_prob(&pp[0], e[0], e[1], 24, uf);
                         adapt_prob(&pp[1], c[0], c[1] + c[2], 24, uf);
                         adapt_prob(&pp[2], c[1], c[2], 24, uf);
                     }
 
     if (s->keyframe || s->intraonly) {
         memcpy(p->skip,  s->prob.p.skip,  sizeof(p->skip));
         memcpy(p->tx32p, s->prob.p.tx32p, sizeof(p->tx32p));
         memcpy(p->tx16p, s->prob.p.tx16p, sizeof(p->tx16p));
         memcpy(p->tx8p,  s->prob.p.tx8p,  sizeof(p->tx8p));
         return;
     }
 
     // skip flag
     for (i = 0; i < 3; i++)
         adapt_prob(&p->skip[i], s->counts.skip[i][0], s->counts.skip[i][1], 20, 128);
 
     // intra/inter flag
     for (i = 0; i < 4; i++)
         adapt_prob(&p->intra[i], s->counts.intra[i][0], s->counts.intra[i][1], 20, 128);
 
     // comppred flag
     if (s->comppredmode == PRED_SWITCHABLE) {
       for (i = 0; i < 5; i++)
           adapt_prob(&p->comp[i], s->counts.comp[i][0], s->counts.comp[i][1], 20, 128);
     }
 
     // reference frames
     if (s->comppredmode != PRED_SINGLEREF) {
       for (i = 0; i < 5; i++)
           adapt_prob(&p->comp_ref[i], s->counts.comp_ref[i][0],
                      s->counts.comp_ref[i][1], 20, 128);
     }
 
     if (s->comppredmode != PRED_COMPREF) {
       for (i = 0; i < 5; i++) {
           uint8_t *pp = p->single_ref[i];
           unsigned (*c)[2] = s->counts.single_ref[i];
 
           adapt_prob(&pp[0], c[0][0], c[0][1], 20, 128);
           adapt_prob(&pp[1], c[1][0], c[1][1], 20, 128);
       }
     }
 
     // block partitioning
     for (i = 0; i < 4; i++)
         for (j = 0; j < 4; j++) {
             uint8_t *pp = p->partition[i][j];
             unsigned *c = s->counts.partition[i][j];
 
             adapt_prob(&pp[0], c[0], c[1] + c[2] + c[3], 20, 128);
             adapt_prob(&pp[1], c[1], c[2] + c[3], 20, 128);
             adapt_prob(&pp[2], c[2], c[3], 20, 128);
         }
 
     // tx size
     if (s->txfmmode == TX_SWITCHABLE) {
       for (i = 0; i < 2; i++) {
           unsigned *c16 = s->counts.tx16p[i], *c32 = s->counts.tx32p[i];
 
           adapt_prob(&p->tx8p[i], s->counts.tx8p[i][0], s->counts.tx8p[i][1], 20, 128);
           adapt_prob(&p->tx16p[i][0], c16[0], c16[1] + c16[2], 20, 128);
           adapt_prob(&p->tx16p[i][1], c16[1], c16[2], 20, 128);
           adapt_prob(&p->tx32p[i][0], c32[0], c32[1] + c32[2] + c32[3], 20, 128);
           adapt_prob(&p->tx32p[i][1], c32[1], c32[2] + c32[3], 20, 128);
           adapt_prob(&p->tx32p[i][2], c32[2], c32[3], 20, 128);
       }
     }
 
     // interpolation filter
     if (s->filtermode == FILTER_SWITCHABLE) {
         for (i = 0; i < 4; i++) {
             uint8_t *pp = p->filter[i];
             unsigned *c = s->counts.filter[i];
 
             adapt_prob(&pp[0], c[0], c[1] + c[2], 20, 128);
             adapt_prob(&pp[1], c[1], c[2], 20, 128);
         }
     }
 
     // inter modes
     for (i = 0; i < 7; i++) {
         uint8_t *pp = p->mv_mode[i];
         unsigned *c = s->counts.mv_mode[i];
 
         adapt_prob(&pp[0], c[2], c[1] + c[0] + c[3], 20, 128);
         adapt_prob(&pp[1], c[0], c[1] + c[3], 20, 128);
         adapt_prob(&pp[2], c[1], c[3], 20, 128);
     }
 
     // mv joints
     {
         uint8_t *pp = p->mv_joint;
         unsigned *c = s->counts.mv_joint;
 
         adapt_prob(&pp[0], c[0], c[1] + c[2] + c[3], 20, 128);
         adapt_prob(&pp[1], c[1], c[2] + c[3], 20, 128);
         adapt_prob(&pp[2], c[2], c[3], 20, 128);
     }
 
     // mv components
     for (i = 0; i < 2; i++) {
         uint8_t *pp;
         unsigned *c, (*c2)[2], sum;
 
         adapt_prob(&p->mv_comp[i].sign, s->counts.mv_comp[i].sign[0],
                    s->counts.mv_comp[i].sign[1], 20, 128);
 
         pp = p->mv_comp[i].classes;
         c = s->counts.mv_comp[i].classes;
         sum = c[1] + c[2] + c[3] + c[4] + c[5] + c[6] + c[7] + c[8] + c[9] + c[10];
         adapt_prob(&pp[0], c[0], sum, 20, 128);
         sum -= c[1];
         adapt_prob(&pp[1], c[1], sum, 20, 128);
         sum -= c[2] + c[3];
         adapt_prob(&pp[2], c[2] + c[3], sum, 20, 128);
         adapt_prob(&pp[3], c[2], c[3], 20, 128);
         sum -= c[4] + c[5];
         adapt_prob(&pp[4], c[4] + c[5], sum, 20, 128);
         adapt_prob(&pp[5], c[4], c[5], 20, 128);
         sum -= c[6];
         adapt_prob(&pp[6], c[6], sum, 20, 128);
         adapt_prob(&pp[7], c[7] + c[8], c[9] + c[10], 20, 128);
         adapt_prob(&pp[8], c[7], c[8], 20, 128);
         adapt_prob(&pp[9], c[9], c[10], 20, 128);
 
         adapt_prob(&p->mv_comp[i].class0, s->counts.mv_comp[i].class0[0],
                    s->counts.mv_comp[i].class0[1], 20, 128);
         pp = p->mv_comp[i].bits;
         c2 = s->counts.mv_comp[i].bits;
         for (j = 0; j < 10; j++)
             adapt_prob(&pp[j], c2[j][0], c2[j][1], 20, 128);
 
         for (j = 0; j < 2; j++) {
             pp = p->mv_comp[i].class0_fp[j];
             c = s->counts.mv_comp[i].class0_fp[j];
             adapt_prob(&pp[0], c[0], c[1] + c[2] + c[3], 20, 128);
             adapt_prob(&pp[1], c[1], c[2] + c[3], 20, 128);
             adapt_prob(&pp[2], c[2], c[3], 20, 128);
         }
         pp = p->mv_comp[i].fp;
         c = s->counts.mv_comp[i].fp;
         adapt_prob(&pp[0], c[0], c[1] + c[2] + c[3], 20, 128);
         adapt_prob(&pp[1], c[1], c[2] + c[3], 20, 128);
         adapt_prob(&pp[2], c[2], c[3], 20, 128);
 
         if (s->highprecisionmvs) {
             adapt_prob(&p->mv_comp[i].class0_hp, s->counts.mv_comp[i].class0_hp[0],
                        s->counts.mv_comp[i].class0_hp[1], 20, 128);
             adapt_prob(&p->mv_comp[i].hp, s->counts.mv_comp[i].hp[0],
                        s->counts.mv_comp[i].hp[1], 20, 128);
         }
     }
 
     // y intra modes
     for (i = 0; i < 4; i++) {
         uint8_t *pp = p->y_mode[i];
         unsigned *c = s->counts.y_mode[i], sum, s2;
 
         sum = c[0] + c[1] + c[3] + c[4] + c[5] + c[6] + c[7] + c[8] + c[9];
         adapt_prob(&pp[0], c[DC_PRED], sum, 20, 128);
         sum -= c[TM_VP8_PRED];
         adapt_prob(&pp[1], c[TM_VP8_PRED], sum, 20, 128);
         sum -= c[VERT_PRED];
         adapt_prob(&pp[2], c[VERT_PRED], sum, 20, 128);
         s2 = c[HOR_PRED] + c[DIAG_DOWN_RIGHT_PRED] + c[VERT_RIGHT_PRED];
         sum -= s2;
         adapt_prob(&pp[3], s2, sum, 20, 128);
         s2 -= c[HOR_PRED];
         adapt_prob(&pp[4], c[HOR_PRED], s2, 20, 128);
         adapt_prob(&pp[5], c[DIAG_DOWN_RIGHT_PRED], c[VERT_RIGHT_PRED], 20, 128);
         sum -= c[DIAG_DOWN_LEFT_PRED];
         adapt_prob(&pp[6], c[DIAG_DOWN_LEFT_PRED], sum, 20, 128);
         sum -= c[VERT_LEFT_PRED];
         adapt_prob(&pp[7], c[VERT_LEFT_PRED], sum, 20, 128);
         adapt_prob(&pp[8], c[HOR_DOWN_PRED], c[HOR_UP_PRED], 20, 128);
     }
 
     // uv intra modes
     for (i = 0; i < 10; i++) {
         uint8_t *pp = p->uv_mode[i];
         unsigned *c = s->counts.uv_mode[i], sum, s2;
 
         sum = c[0] + c[1] + c[3] + c[4] + c[5] + c[6] + c[7] + c[8] + c[9];
         adapt_prob(&pp[0], c[DC_PRED], sum, 20, 128);
         sum -= c[TM_VP8_PRED];
         adapt_prob(&pp[1], c[TM_VP8_PRED], sum, 20, 128);
         sum -= c[VERT_PRED];
         adapt_prob(&pp[2], c[VERT_PRED], sum, 20, 128);
         s2 = c[HOR_PRED] + c[DIAG_DOWN_RIGHT_PRED] + c[VERT_RIGHT_PRED];
         sum -= s2;
         adapt_prob(&pp[3], s2, sum, 20, 128);
         s2 -= c[HOR_PRED];
         adapt_prob(&pp[4], c[HOR_PRED], s2, 20, 128);
         adapt_prob(&pp[5], c[DIAG_DOWN_RIGHT_PRED], c[VERT_RIGHT_PRED], 20, 128);
         sum -= c[DIAG_DOWN_LEFT_PRED];
         adapt_prob(&pp[6], c[DIAG_DOWN_LEFT_PRED], sum, 20, 128);
         sum -= c[VERT_LEFT_PRED];
         adapt_prob(&pp[7], c[VERT_LEFT_PRED], sum, 20, 128);
         adapt_prob(&pp[8], c[HOR_DOWN_PRED], c[HOR_UP_PRED], 20, 128);
     }
 }
 

 static void free_buffers(VP9Context *s)
 {

     av_freep(&s->intra_pred_data[0]);

     av_freep(&s->b_base);
     av_freep(&s->block_base);
 }
 

 static av_cold int vp9_decode_free(AVCodecContext *ctx)
 {
     VP9Context *s = ctx->priv_data;
     int i;
 

     for (i = 0; i < 3; i++) {

         if (s->frames[i].tf.f->data[0])
             vp9_unref_frame(ctx, &s->frames[i]);
         av_frame_free(&s->frames[i].tf.f);
     }
     for (i = 0; i < 8; i++) {
         if (s->refs[i].f->data[0])
             ff_thread_release_buffer(ctx, &s->refs[i]);
         av_frame_free(&s->refs[i].f);
         if (s->next_refs[i].f->data[0])
             ff_thread_release_buffer(ctx, &s->next_refs[i]);
         av_frame_free(&s->next_refs[i].f);
     }

     free_buffers(s);

     av_freep(&s->c_b);

     s->c_b_size = 0;

 
     return 0;
 }
 
 

 static int vp9_decode_frame(AVCodecContext *ctx, void *frame,

                             int *got_frame, AVPacket *pkt)

 {

     const uint8_t *data = pkt->data;
     int size = pkt->size;

     VP9Context *s = ctx->priv_data;
     int res, tile_row, tile_col, i, ref, row, col;

     int retain_segmap_ref = s->frames[REF_FRAME_SEGMAP].segmentation_map &&

                             (!s->segmentation.enabled || !s->segmentation.update_map);

     ptrdiff_t yoff, uvoff, ls_y, ls_uv;

     AVFrame *f;

     int bytesperpixel;

 
     if ((res = decode_frame_header(ctx, data, size, &ref)) < 0) {
         return res;
     } else if (res == 0) {

         if (!s->refs[ref].f->data[0]) {

             av_log(ctx, AV_LOG_ERROR, "Requested reference %d not available\n", ref);
             return AVERROR_INVALIDDATA;
         }

         if ((res = av_frame_ref(frame, s->refs[ref].f)) < 0)

             return res;

         ((AVFrame *)frame)->pkt_pts = pkt->pts;
         ((AVFrame *)frame)->pkt_dts = pkt->dts;

         for (i = 0; i < 8; i++) {
             if (s->next_refs[i].f->data[0])
                 ff_thread_release_buffer(ctx, &s->next_refs[i]);
             if (s->refs[i].f->data[0] &&
                 (res = ff_thread_ref_frame(&s->next_refs[i], &s->refs[i])) < 0)
                 return res;
         }

         *got_frame = 1;

         return pkt->size;

     }
     data += res;
     size -= res;
 

     if (!retain_segmap_ref || s->keyframe || s->intraonly) {

         if (s->frames[REF_FRAME_SEGMAP].tf.f->data[0])
             vp9_unref_frame(ctx, &s->frames[REF_FRAME_SEGMAP]);
         if (!s->keyframe && !s->intraonly && !s->errorres && s->frames[CUR_FRAME].tf.f->data[0] &&
             (res = vp9_ref_frame(ctx, &s->frames[REF_FRAME_SEGMAP], &s->frames[CUR_FRAME])) < 0)
             return res;
     }
     if (s->frames[REF_FRAME_MVPAIR].tf.f->data[0])
         vp9_unref_frame(ctx, &s->frames[REF_FRAME_MVPAIR]);
     if (!s->intraonly && !s->keyframe && !s->errorres && s->frames[CUR_FRAME].tf.f->data[0] &&
         (res = vp9_ref_frame(ctx, &s->frames[REF_FRAME_MVPAIR], &s->frames[CUR_FRAME])) < 0)

         return res;
     if (s->frames[CUR_FRAME].tf.f->data[0])
         vp9_unref_frame(ctx, &s->frames[CUR_FRAME]);
     if ((res = vp9_alloc_frame(ctx, &s->frames[CUR_FRAME])) < 0)

         return res;

     f = s->frames[CUR_FRAME].tf.f;
     f->key_frame = s->keyframe;

     f->pict_type = (s->keyframe || s->intraonly) ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;

     ls_y = f->linesize[0];
     ls_uv =f->linesize[1];
 
     // ref frame setup

     for (i = 0; i < 8; i++) {
         if (s->next_refs[i].f->data[0])
             ff_thread_release_buffer(ctx, &s->next_refs[i]);

         if (s->refreshrefmask & (1 << i)) {

             res = ff_thread_ref_frame(&s->next_refs[i], &s->frames[CUR_FRAME].tf);

         } else if (s->refs[i].f->data[0]) {

             res = ff_thread_ref_frame(&s->next_refs[i], &s->refs[i]);

         }

         if (res < 0)
             return res;
     }

 
     // main tile decode loop

     bytesperpixel = s->bytesperpixel;

     memset(s->above_partition_ctx, 0, s->cols);
     memset(s->above_skip_ctx, 0, s->cols);
     if (s->keyframe || s->intraonly) {
         memset(s->above_mode_ctx, DC_PRED, s->cols * 2);
     } else {
         memset(s->above_mode_ctx, NEARESTMV, s->cols);
     }
     memset(s->above_y_nnz_ctx, 0, s->sb_cols * 16);

     memset(s->above_uv_nnz_ctx[0], 0, s->sb_cols * 16 >> s->ss_h);
     memset(s->above_uv_nnz_ctx[1], 0, s->sb_cols * 16 >> s->ss_h);

     memset(s->above_segpred_ctx, 0, s->cols);

     s->pass = s->frames[CUR_FRAME].uses_2pass =

         ctx->active_thread_type == FF_THREAD_FRAME && s->refreshctx && !s->parallelmode;

     if ((res = update_block_buffers(ctx)) < 0) {
         av_log(ctx, AV_LOG_ERROR,
                "Failed to allocate block buffers\n");
         return res;
     }

     if (s->refreshctx && s->parallelmode) {
         int j, k, l, m;
 

         for (i = 0; i < 4; i++) {

             for (j = 0; j < 2; j++)
                 for (k = 0; k < 2; k++)
                     for (l = 0; l < 6; l++)
                         for (m = 0; m < 6; m++)
                             memcpy(s->prob_ctx[s->framectxid].coef[i][j][k][l][m],
                                    s->prob.coef[i][j][k][l][m], 3);

             if (s->txfmmode == i)
                 break;
         }

         s->prob_ctx[s->framectxid].p = s->prob.p;
         ff_thread_finish_setup(ctx);

     } else if (!s->refreshctx) {
         ff_thread_finish_setup(ctx);

     }
 
     do {
         yoff = uvoff = 0;
         s->b = s->b_base;
         s->block = s->block_base;
         s->uvblock[0] = s->uvblock_base[0];
         s->uvblock[1] = s->uvblock_base[1];
         s->eob = s->eob_base;
         s->uveob[0] = s->uveob_base[0];
         s->uveob[1] = s->uveob_base[1];
 

         for (tile_row = 0; tile_row < s->tiling.tile_rows; tile_row++) {
             set_tile_offset(&s->tiling.tile_row_start, &s->tiling.tile_row_end,
                             tile_row, s->tiling.log2_tile_rows, s->sb_rows);

             if (s->pass != 2) {

                 for (tile_col = 0; tile_col < s->tiling.tile_cols; tile_col++) {

                     int64_t tile_size;

                     if (tile_col == s->tiling.tile_cols - 1 &&
                         tile_row == s->tiling.tile_rows - 1) {
                         tile_size = size;
                     } else {
                         tile_size = AV_RB32(data);
                         data += 4;
                         size -= 4;
                     }

                     if (tile_size > size) {
                         ff_thread_report_progress(&s->frames[CUR_FRAME].tf, INT_MAX, 0);

                         return AVERROR_INVALIDDATA;

                     }

                     ff_vp56_init_range_decoder(&s->c_b[tile_col], data, tile_size);

                     if (vp56_rac_get_prob_branchy(&s->c_b[tile_col], 128)) { // marker bit
                         ff_thread_report_progress(&s->frames[CUR_FRAME].tf, INT_MAX, 0);

                         return AVERROR_INVALIDDATA;

                     }

                     data += tile_size;
                     size -= tile_size;
                 }

             }

             for (row = s->tiling.tile_row_start; row < s->tiling.tile_row_end;

                  row += 8, yoff += ls_y * 64, uvoff += ls_uv * 64 >> s->ss_v) {

                 struct VP9Filter *lflvl_ptr = s->lflvl;
                 ptrdiff_t yoff2 = yoff, uvoff2 = uvoff;

                 for (tile_col = 0; tile_col < s->tiling.tile_cols; tile_col++) {
                     set_tile_offset(&s->tiling.tile_col_start, &s->tiling.tile_col_end,
                                     tile_col, s->tiling.log2_tile_cols, s->sb_cols);

                     if (s->pass != 2) {

                         memset(s->left_partition_ctx, 0, 8);
                         memset(s->left_skip_ctx, 0, 8);
                         if (s->keyframe || s->intraonly) {
                             memset(s->left_mode_ctx, DC_PRED, 16);
                         } else {
                             memset(s->left_mode_ctx, NEARESTMV, 8);
                         }
                         memset(s->left_y_nnz_ctx, 0, 16);

                         memset(s->left_uv_nnz_ctx, 0, 32);

                         memset(s->left_segpred_ctx, 0, 8);

                         memcpy(&s->c, &s->c_b[tile_col], sizeof(s->c));

                     }
 

                     for (col = s->tiling.tile_col_start;
                          col < s->tiling.tile_col_end;

                          col += 8, yoff2 += 64 * bytesperpixel,
                          uvoff2 += 64 * bytesperpixel >> s->ss_h, lflvl_ptr++) {

                         // FIXME integrate with lf code (i.e. zero after each
                         // use, similar to invtxfm coefficients, or similar)

                         if (s->pass != 1) {

                             memset(lflvl_ptr->mask, 0, sizeof(lflvl_ptr->mask));

                         }

                         if (s->pass == 2) {

                             decode_sb_mem(ctx, row, col, lflvl_ptr,
                                           yoff2, uvoff2, BL_64X64);

                         } else {

                             decode_sb(ctx, row, col, lflvl_ptr,
                                       yoff2, uvoff2, BL_64X64);

                         }

                     }

                     if (s->pass != 2) {

                         memcpy(&s->c_b[tile_col], &s->c, sizeof(s->c));

                     }

                 }

                 if (s->pass == 1) {
                     continue;
                 }
 

                 // backup pre-loopfilter reconstruction data for intra
                 // prediction of next row of sb64s
                 if (row + 8 < s->rows) {
                     memcpy(s->intra_pred_data[0],
                            f->data[0] + yoff + 63 * ls_y,

                            8 * s->cols * bytesperpixel);

                     memcpy(s->intra_pred_data[1],

                            f->data[1] + uvoff + ((64 >> s->ss_v) - 1) * ls_uv,

                            8 * s->cols * bytesperpixel >> s->ss_h);

                     memcpy(s->intra_pred_data[2],

                            f->data[2] + uvoff + ((64 >> s->ss_v) - 1) * ls_uv,

                            8 * s->cols * bytesperpixel >> s->ss_h);

                 }
 
                 // loopfilter one row
                 if (s->filter.level) {
                     yoff2 = yoff;
                     uvoff2 = uvoff;
                     lflvl_ptr = s->lflvl;
                     for (col = 0; col < s->cols;

                          col += 8, yoff2 += 64 * bytesperpixel,
                          uvoff2 += 64 * bytesperpixel >> s->ss_h, lflvl_ptr++) {

                         loopfilter_sb(ctx, lflvl_ptr, row, col, yoff2, uvoff2);
                     }

                 }

 
                 // FIXME maybe we can make this more finegrained by running the
                 // loopfilter per-block instead of after each sbrow
                 // In fact that would also make intra pred left preparation easier?
                 ff_thread_report_progress(&s->frames[CUR_FRAME].tf, row >> 3, 0);

             }

         }
 

         if (s->pass < 2 && s->refreshctx && !s->parallelmode) {

             adapt_probs(s);

             ff_thread_finish_setup(ctx);

         }

     } while (s->pass++ == 1);
     ff_thread_report_progress(&s->frames[CUR_FRAME].tf, INT_MAX, 0);

 
     // ref frame setup

     for (i = 0; i < 8; i++) {
         if (s->refs[i].f->data[0])
             ff_thread_release_buffer(ctx, &s->refs[i]);
         ff_thread_ref_frame(&s->refs[i], &s->next_refs[i]);
     }

     if (!s->invisible) {
         if ((res = av_frame_ref(frame, s->frames[CUR_FRAME].tf.f)) < 0)
             return res;

         *got_frame = 1;
     }
 

     return pkt->size;

 }
 
 static void vp9_decode_flush(AVCodecContext *ctx)
 {
     VP9Context *s = ctx->priv_data;
     int i;
 

     for (i = 0; i < 3; i++)

         vp9_unref_frame(ctx, &s->frames[i]);

     for (i = 0; i < 8; i++)

         ff_thread_release_buffer(ctx, &s->refs[i]);

 }
 

 static int init_frames(AVCodecContext *ctx)

 {
     VP9Context *s = ctx->priv_data;
     int i;
 

     for (i = 0; i < 3; i++) {

         s->frames[i].tf.f = av_frame_alloc();
         if (!s->frames[i].tf.f) {
             vp9_decode_free(ctx);
             av_log(ctx, AV_LOG_ERROR, "Failed to allocate frame buffer %d\n", i);
             return AVERROR(ENOMEM);
         }
     }

     for (i = 0; i < 8; i++) {

         s->refs[i].f = av_frame_alloc();
         s->next_refs[i].f = av_frame_alloc();
         if (!s->refs[i].f || !s->next_refs[i].f) {

             vp9_decode_free(ctx);

             av_log(ctx, AV_LOG_ERROR, "Failed to allocate frame buffer %d\n", i);
             return AVERROR(ENOMEM);
         }
     }
 
     return 0;
 }
 

 static av_cold int vp9_decode_init(AVCodecContext *ctx)
 {
     VP9Context *s = ctx->priv_data;
 

     ctx->internal->allocate_progress = 1;

     s->last_bpp = 0;

     s->filter.sharpness = -1;
 
     return init_frames(ctx);
 }
 

 static av_cold int vp9_decode_init_thread_copy(AVCodecContext *avctx)
 {
     return init_frames(avctx);
 }
 
 static int vp9_decode_update_thread_context(AVCodecContext *dst, const AVCodecContext *src)
 {
     int i, res;
     VP9Context *s = dst->priv_data, *ssrc = src->priv_data;
 

     // detect size changes in other threads

     if (s->intra_pred_data[0] &&
         (!ssrc->intra_pred_data[0] || s->cols != ssrc->cols || s->rows != ssrc->rows)) {

         free_buffers(s);
     }

     for (i = 0; i < 3; i++) {

         if (s->frames[i].tf.f->data[0])
             vp9_unref_frame(dst, &s->frames[i]);
         if (ssrc->frames[i].tf.f->data[0]) {
             if ((res = vp9_ref_frame(dst, &s->frames[i], &ssrc->frames[i])) < 0)
                 return res;
         }
     }
     for (i = 0; i < 8; i++) {
         if (s->refs[i].f->data[0])
             ff_thread_release_buffer(dst, &s->refs[i]);
         if (ssrc->next_refs[i].f->data[0]) {
             if ((res = ff_thread_ref_frame(&s->refs[i], &ssrc->next_refs[i])) < 0)
                 return res;
         }
     }
 
     s->invisible = ssrc->invisible;
     s->keyframe = ssrc->keyframe;

     s->intraonly = ssrc->intraonly;

     s->ss_v = ssrc->ss_v;
     s->ss_h = ssrc->ss_h;

     s->segmentation.enabled = ssrc->segmentation.enabled;
     s->segmentation.update_map = ssrc->segmentation.update_map;

     s->bytesperpixel = ssrc->bytesperpixel;
     s->bpp = ssrc->bpp;
     s->bpp_index = ssrc->bpp_index;

     memcpy(&s->prob_ctx, &ssrc->prob_ctx, sizeof(s->prob_ctx));
     memcpy(&s->lf_delta, &ssrc->lf_delta, sizeof(s->lf_delta));
     if (ssrc->segmentation.enabled) {
         memcpy(&s->segmentation.feat, &ssrc->segmentation.feat,
                sizeof(s->segmentation.feat));
     }
 
     return 0;
 }
 

 static const AVProfile profiles[] = {
     { FF_PROFILE_VP9_0, "Profile 0" },
     { FF_PROFILE_VP9_1, "Profile 1" },

     { FF_PROFILE_VP9_2, "Profile 2" },
     { FF_PROFILE_VP9_3, "Profile 3" },

     { FF_PROFILE_UNKNOWN },
 };
 

 AVCodec ff_vp9_decoder = {

     .name                  = "vp9",
     .long_name             = NULL_IF_CONFIG_SMALL("Google VP9"),
     .type                  = AVMEDIA_TYPE_VIDEO,
     .id                    = AV_CODEC_ID_VP9,
     .priv_data_size        = sizeof(VP9Context),
     .init                  = vp9_decode_init,
     .close                 = vp9_decode_free,

     .decode                = vp9_decode_frame,

     .capabilities          = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,

     .flush                 = vp9_decode_flush,
     .init_thread_copy      = ONLY_IF_THREADS_ENABLED(vp9_decode_init_thread_copy),
     .update_thread_context = ONLY_IF_THREADS_ENABLED(vp9_decode_update_thread_context),

     .profiles              = NULL_IF_CONFIG_SMALL(profiles),

 };