/*

  * Copyright (c) 2003 The FFmpeg Project

  *

  * 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

  */
 
 /*

  * How to use this decoder:
  * SVQ3 data is transported within Apple Quicktime files. Quicktime files

  * have stsd atoms to describe media trak properties. A stsd atom for a
  * video trak contains 1 or more ImageDescription atoms. These atoms begin
  * with the 4-byte length of the atom followed by the codec fourcc. Some
  * decoders need information in this atom to operate correctly. Such
  * is the case with SVQ3. In order to get the best use out of this decoder,
  * the calling app must make the SVQ3 ImageDescription atom available

  * via the AVCodecContext's extradata[_size] field:
  *

  * AVCodecContext.extradata = pointer to ImageDescription, first characters

  * are expected to be 'S', 'V', 'Q', and '3', NOT the 4-byte atom length

  * AVCodecContext.extradata_size = size of ImageDescription atom memory
  * buffer (which will be the same as the ImageDescription atom size field

  * from the QT file, minus 4 bytes since the length is missing)
  *
  * You will know you have these parameters passed correctly when the decoder
  * correctly decodes this file:

  *  http://samples.mplayerhq.hu/V-codecs/SVQ3/Vertical400kbit.sorenson3.mov

  */

 #include "internal.h"
 #include "avcodec.h"
 #include "mpegvideo.h"
 #include "h264.h"
 

 #include "h264data.h" // FIXME FIXME FIXME

 #include "h264_mvpred.h"

 #include "golomb.h"
 #include "rectangle.h"
 #include "vdpau_internal.h"
 

 #if CONFIG_ZLIB

 #include <zlib.h>
 #endif
 

 #include "svq1.h"

 #include "svq3.h"

 /**

  * @file

  * svq3 decoder.
  */
 

 typedef struct {
     H264Context h;

     Picture *cur_pic;
     Picture *next_pic;
     Picture *last_pic;

     int halfpel_flag;
     int thirdpel_flag;
     int unknown_flag;
     int next_slice_index;
     uint32_t watermark_key;

     uint8_t *buf;
     int buf_size;

     int adaptive_quant;
     int next_p_frame_damaged;
     int h_edge_pos;
     int v_edge_pos;
     int last_frame_output;

 } SVQ3Context;
 

 #define FULLPEL_MODE  1
 #define HALFPEL_MODE  2

 #define THIRDPEL_MODE 3

 #define PREDICT_MODE  4

 /* dual scan (from some older h264 draft)

  * o-->o-->o   o
  *         |  /|
  * o   o   o / o
  * | / |   |/  |
  * o   o   o   o
  *   /
  * o-->o-->o-->o
  */

 static const uint8_t svq3_scan[16] = {

     0 + 0 * 4, 1 + 0 * 4, 2 + 0 * 4, 2 + 1 * 4,
     2 + 2 * 4, 3 + 0 * 4, 3 + 1 * 4, 3 + 2 * 4,
     0 + 1 * 4, 0 + 2 * 4, 1 + 1 * 4, 1 + 2 * 4,
     0 + 3 * 4, 1 + 3 * 4, 2 + 3 * 4, 3 + 3 * 4,

 };
 
 static const uint8_t svq3_pred_0[25][2] = {

     { 0, 0 },
     { 1, 0 }, { 0, 1 },
     { 0, 2 }, { 1, 1 }, { 2, 0 },
     { 3, 0 }, { 2, 1 }, { 1, 2 }, { 0, 3 },
     { 0, 4 }, { 1, 3 }, { 2, 2 }, { 3, 1 }, { 4, 0 },
     { 4, 1 }, { 3, 2 }, { 2, 3 }, { 1, 4 },
     { 2, 4 }, { 3, 3 }, { 4, 2 },
     { 4, 3 }, { 3, 4 },
     { 4, 4 }

 };
 
 static const int8_t svq3_pred_1[6][6][5] = {

     { { 2, -1, -1, -1, -1 }, { 2, 1, -1, -1, -1 }, { 1, 2, -1, -1, -1 },
       { 2,  1, -1, -1, -1 }, { 1, 2, -1, -1, -1 }, { 1, 2, -1, -1, -1 } },
     { { 0,  2, -1, -1, -1 }, { 0, 2,  1,  4,  3 }, { 0, 1,  2,  4,  3 },
       { 0,  2,  1,  4,  3 }, { 2, 0,  1,  3,  4 }, { 0, 4,  2,  1,  3 } },
     { { 2,  0, -1, -1, -1 }, { 2, 1,  0,  4,  3 }, { 1, 2,  4,  0,  3 },
       { 2,  1,  0,  4,  3 }, { 2, 1,  4,  3,  0 }, { 1, 2,  4,  0,  3 } },
     { { 2,  0, -1, -1, -1 }, { 2, 0,  1,  4,  3 }, { 1, 2,  0,  4,  3 },
       { 2,  1,  0,  4,  3 }, { 2, 1,  3,  4,  0 }, { 2, 4,  1,  0,  3 } },
     { { 0,  2, -1, -1, -1 }, { 0, 2,  1,  3,  4 }, { 1, 2,  3,  0,  4 },
       { 2,  0,  1,  3,  4 }, { 2, 1,  3,  0,  4 }, { 2, 0,  4,  3,  1 } },
     { { 0,  2, -1, -1, -1 }, { 0, 2,  4,  1,  3 }, { 1, 4,  2,  0,  3 },
       { 4,  2,  0,  1,  3 }, { 2, 0,  1,  4,  3 }, { 4, 2,  1,  0,  3 } },

 };
 

 static const struct {
     uint8_t run;
     uint8_t level;
 } svq3_dct_tables[2][16] = {

     { { 0, 0 }, { 0, 1 }, { 1, 1 }, { 2, 1 }, { 0, 2 }, { 3, 1 }, { 4, 1 }, { 5, 1 },
       { 0, 3 }, { 1, 2 }, { 2, 2 }, { 6, 1 }, { 7, 1 }, { 8, 1 }, { 9, 1 }, { 0, 4 } },
     { { 0, 0 }, { 0, 1 }, { 1, 1 }, { 0, 2 }, { 2, 1 }, { 0, 3 }, { 0, 4 }, { 0, 5 },
       { 3, 1 }, { 4, 1 }, { 1, 2 }, { 1, 3 }, { 0, 6 }, { 0, 7 }, { 0, 8 }, { 0, 9 } }

 };
 
 static const uint32_t svq3_dequant_coeff[32] = {

      3881,  4351,  4890,  5481,   6154,   6914,   7761,   8718,
      9781, 10987, 12339, 13828,  15523,  17435,  19561,  21873,
     24552, 27656, 30847, 34870,  38807,  43747,  49103,  54683,
     61694, 68745, 77615, 89113, 100253, 109366, 126635, 141533

 };
 

 void ff_svq3_luma_dc_dequant_idct_c(int16_t *output, int16_t *input, int qp)

 {

     const int qmul = svq3_dequant_coeff[qp];

 #define stride 16
     int i;
     int temp[16];

     static const uint8_t x_offset[4] = { 0, 1 * stride, 4 * stride, 5 * stride };
 
     for (i = 0; i < 4; i++) {
         const int z0 = 13 * (input[4 * i + 0] +      input[4 * i + 2]);
         const int z1 = 13 * (input[4 * i + 0] -      input[4 * i + 2]);
         const int z2 =  7 *  input[4 * i + 1] - 17 * input[4 * i + 3];
         const int z3 = 17 *  input[4 * i + 1] +  7 * input[4 * i + 3];
 
         temp[4 * i + 0] = z0 + z3;
         temp[4 * i + 1] = z1 + z2;
         temp[4 * i + 2] = z1 - z2;
         temp[4 * i + 3] = z0 - z3;

     }
 

     for (i = 0; i < 4; i++) {
         const int offset = x_offset[i];
         const int z0     = 13 * (temp[4 * 0 + i] +      temp[4 * 2 + i]);
         const int z1     = 13 * (temp[4 * 0 + i] -      temp[4 * 2 + i]);
         const int z2     =  7 *  temp[4 * 1 + i] - 17 * temp[4 * 3 + i];
         const int z3     = 17 *  temp[4 * 1 + i] +  7 * temp[4 * 3 + i];
 

         output[stride *  0 + offset] = (z0 + z3) * qmul + 0x80000 >> 20;
         output[stride *  2 + offset] = (z1 + z2) * qmul + 0x80000 >> 20;
         output[stride *  8 + offset] = (z1 - z2) * qmul + 0x80000 >> 20;
         output[stride * 10 + offset] = (z0 - z3) * qmul + 0x80000 >> 20;

     }
 }
 #undef stride
 

 void ff_svq3_add_idct_c(uint8_t *dst, int16_t *block,

                         int stride, int qp, int dc)

 {

     const int qmul = svq3_dequant_coeff[qp];

     int i;
 
     if (dc) {

         dc       = 13 * 13 * (dc == 1 ? 1538 * block[0]
                                       : qmul * (block[0] >> 3) / 2);

         block[0] = 0;
     }
 

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

         const int z0 = 13 * (block[0 + 4 * i] +      block[2 + 4 * i]);
         const int z1 = 13 * (block[0 + 4 * i] -      block[2 + 4 * i]);
         const int z2 =  7 *  block[1 + 4 * i] - 17 * block[3 + 4 * i];
         const int z3 = 17 *  block[1 + 4 * i] +  7 * block[3 + 4 * i];
 
         block[0 + 4 * i] = z0 + z3;
         block[1 + 4 * i] = z1 + z2;
         block[2 + 4 * i] = z1 - z2;
         block[3 + 4 * i] = z0 - z3;

     }
 

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

         const int z0 = 13 * (block[i + 4 * 0] +      block[i + 4 * 2]);
         const int z1 = 13 * (block[i + 4 * 0] -      block[i + 4 * 2]);
         const int z2 =  7 *  block[i + 4 * 1] - 17 * block[i + 4 * 3];
         const int z3 = 17 *  block[i + 4 * 1] +  7 * block[i + 4 * 3];

         const int rr = (dc + 0x80000);
 

         dst[i + stride * 0] = av_clip_uint8(dst[i + stride * 0] + ((z0 + z3) * qmul + rr >> 20));
         dst[i + stride * 1] = av_clip_uint8(dst[i + stride * 1] + ((z1 + z2) * qmul + rr >> 20));
         dst[i + stride * 2] = av_clip_uint8(dst[i + stride * 2] + ((z1 - z2) * qmul + rr >> 20));
         dst[i + stride * 3] = av_clip_uint8(dst[i + stride * 3] + ((z0 - z3) * qmul + rr >> 20));

     }

 
     memset(block, 0, 16 * sizeof(int16_t));

 }
 

 static inline int svq3_decode_block(GetBitContext *gb, int16_t *block,

                                     int index, const int type)
 {

     static const uint8_t *const scan_patterns[4] =
     { luma_dc_zigzag_scan, zigzag_scan, svq3_scan, chroma_dc_scan };

     int run, level, sign, limit;

     unsigned vlc;

     const int intra           = 3 * type >> 2;

     const uint8_t *const scan = scan_patterns[type];

     for (limit = (16 >> intra); index < 16; index = limit, limit += 8) {
         for (; (vlc = svq3_get_ue_golomb(gb)) != 0; index++) {

             if ((int32_t)vlc < 0)

                 return -1;

             sign     = (vlc & 1) ? 0 : -1;

             vlc      = vlc + 1 >> 1;

 
             if (type == 3) {
                 if (vlc < 3) {
                     run   = 0;
                     level = vlc;
                 } else if (vlc < 4) {
                     run   = 1;
                     level = 1;
                 } else {

                     run   = vlc & 0x3;
                     level = (vlc + 9 >> 2) - run;

                 }
             } else {

                 if (vlc < 16U) {

                     run   = svq3_dct_tables[intra][vlc].run;
                     level = svq3_dct_tables[intra][vlc].level;
                 } else if (intra) {

                     run   = vlc & 0x7;

                     level = (vlc >> 3) + ((run == 0) ? 8 : ((run < 2) ? 2 : ((run < 5) ? 0 : -1)));

                 } else {

                     run   = vlc & 0xF;

                     level = (vlc >> 4) + ((run == 0) ? 4 : ((run < 3) ? 2 : ((run < 10) ? 1 : 0)));

                 }
             }

             if ((index += run) >= limit)
                 return -1;
 
             block[scan[index]] = (level ^ sign) - sign;

         }

         if (type != 2) {
             break;
         }

     }
 

     return 0;

 }
 

 static inline void svq3_mc_dir_part(SVQ3Context *s,

                                     int x, int y, int width, int height,
                                     int mx, int my, int dxy,
                                     int thirdpel, int dir, int avg)
 {

     H264Context *h     = &s->h;
     const Picture *pic = (dir == 0) ? s->last_pic : s->next_pic;

     uint8_t *src, *dest;
     int i, emu = 0;

     int blocksize = 2 - (width >> 3); // 16->0, 8->1, 4->2

 
     mx += x;
     my += y;

     if (mx < 0 || mx >= s->h_edge_pos - width  - 1 ||
         my < 0 || my >= s->v_edge_pos - height - 1) {

         emu = 1;

         mx = av_clip(mx, -16, s->h_edge_pos - width  + 15);
         my = av_clip(my, -16, s->v_edge_pos - height + 15);

     }
 

     /* form component predictions */

     dest = h->cur_pic.f.data[0] + x + y * h->linesize;
     src  = pic->f.data[0] + mx + my * h->linesize;

 
     if (emu) {

         h->vdsp.emulated_edge_mc(h->edge_emu_buffer, src, h->linesize,

                                  width + 1, height + 1,
                                  mx, my, s->h_edge_pos, s->v_edge_pos);

         src = h->edge_emu_buffer;

     }

     if (thirdpel)

         (avg ? h->dsp.avg_tpel_pixels_tab
              : h->dsp.put_tpel_pixels_tab)[dxy](dest, src, h->linesize,

                                                 width, height);

     else

         (avg ? h->dsp.avg_pixels_tab
              : h->dsp.put_pixels_tab)[blocksize][dxy](dest, src, h->linesize,

                                                       height);

     if (!(h->flags & CODEC_FLAG_GRAY)) {

         mx     = mx + (mx < (int) x) >> 1;
         my     = my + (my < (int) y) >> 1;
         width  = width  >> 1;
         height = height >> 1;

         blocksize++;
 
         for (i = 1; i < 3; i++) {

             dest = h->cur_pic.f.data[i] + (x >> 1) + (y >> 1) * h->uvlinesize;
             src  = pic->f.data[i] + mx + my * h->uvlinesize;

 
             if (emu) {

                 h->vdsp.emulated_edge_mc(h->edge_emu_buffer, src, h->uvlinesize,

                                          width + 1, height + 1,
                                          mx, my, (s->h_edge_pos >> 1),
                                          s->v_edge_pos >> 1);

                 src = h->edge_emu_buffer;

             }
             if (thirdpel)

                 (avg ? h->dsp.avg_tpel_pixels_tab
                      : h->dsp.put_tpel_pixels_tab)[dxy](dest, src,
                                                         h->uvlinesize,

                                                         width, height);

             else

                 (avg ? h->dsp.avg_pixels_tab
                      : h->dsp.put_pixels_tab)[blocksize][dxy](dest, src,
                                                               h->uvlinesize,

                                                               height);

         }
     }

 }
 

 static inline int svq3_mc_dir(SVQ3Context *s, int size, int mode,

                               int dir, int avg)

 {

     int i, j, k, mx, my, dx, dy, x, y;

     H264Context *h          = &s->h;

     const int part_width    = ((size & 5) == 4) ? 4 : 16 >> (size & 1);
     const int part_height   = 16 >> ((unsigned)(size + 1) / 3);
     const int extra_width   = (mode == PREDICT_MODE) ? -16 * 6 : 0;
     const int h_edge_pos    = 6 * (s->h_edge_pos - part_width)  - extra_width;
     const int v_edge_pos    = 6 * (s->v_edge_pos - part_height) - extra_width;
 
     for (i = 0; i < 16; i += part_height)

         for (j = 0; j < 16; j += part_width) {

             const int b_xy = (4 * h->mb_x + (j >> 2)) +
                              (4 * h->mb_y + (i >> 2)) * h->b_stride;

             int dxy;

             x = 16 * h->mb_x + j;
             y = 16 * h->mb_y + i;

             k = (j >> 2 & 1) + (i >> 1 & 2) +
                 (j >> 1 & 4) + (i      & 8);

 
             if (mode != PREDICT_MODE) {

                 pred_motion(h, k, part_width >> 2, dir, 1, &mx, &my);

             } else {

                 mx = s->next_pic->f.motion_val[0][b_xy][0] << 1;
                 my = s->next_pic->f.motion_val[0][b_xy][1] << 1;

 
                 if (dir == 0) {

                     mx = mx * h->frame_num_offset /
                          h->prev_frame_num_offset + 1 >> 1;
                     my = my * h->frame_num_offset /
                          h->prev_frame_num_offset + 1 >> 1;

                 } else {

                     mx = mx * (h->frame_num_offset - h->prev_frame_num_offset) /
                          h->prev_frame_num_offset + 1 >> 1;
                     my = my * (h->frame_num_offset - h->prev_frame_num_offset) /
                          h->prev_frame_num_offset + 1 >> 1;

                 }
             }
 
             /* clip motion vector prediction to frame border */

             mx = av_clip(mx, extra_width - 6 * x, h_edge_pos - 6 * x);
             my = av_clip(my, extra_width - 6 * y, v_edge_pos - 6 * y);

 
             /* get (optional) motion vector differential */
             if (mode == PREDICT_MODE) {
                 dx = dy = 0;
             } else {

                 dy = svq3_get_se_golomb(&h->gb);
                 dx = svq3_get_se_golomb(&h->gb);

 
                 if (dx == INVALID_VLC || dy == INVALID_VLC) {

                     av_log(h->avctx, AV_LOG_ERROR, "invalid MV vlc\n");

                     return -1;
                 }
             }
 
             /* compute motion vector */
             if (mode == THIRDPEL_MODE) {
                 int fx, fy;

                 mx  = (mx + 1 >> 1) + dx;
                 my  = (my + 1 >> 1) + dy;
                 fx  = (unsigned)(mx + 0x3000) / 3 - 0x1000;
                 fy  = (unsigned)(my + 0x3000) / 3 - 0x1000;

                 dxy = (mx - 3 * fx) + 4 * (my - 3 * fy);
 
                 svq3_mc_dir_part(s, x, y, part_width, part_height,
                                  fx, fy, dxy, 1, dir, avg);

                 mx += mx;
                 my += my;
             } else if (mode == HALFPEL_MODE || mode == PREDICT_MODE) {

                 mx  = (unsigned)(mx + 1 + 0x3000) / 3 + dx - 0x1000;
                 my  = (unsigned)(my + 1 + 0x3000) / 3 + dy - 0x1000;

                 dxy = (mx & 1) + 2 * (my & 1);

                 svq3_mc_dir_part(s, x, y, part_width, part_height,
                                  mx >> 1, my >> 1, dxy, 0, dir, avg);

                 mx *= 3;
                 my *= 3;
             } else {

                 mx = (unsigned)(mx + 3 + 0x6000) / 6 + dx - 0x1000;
                 my = (unsigned)(my + 3 + 0x6000) / 6 + dy - 0x1000;

                 svq3_mc_dir_part(s, x, y, part_width, part_height,
                                  mx, my, 0, 0, dir, avg);

                 mx *= 6;
                 my *= 6;
             }
 
             /* update mv_cache */
             if (mode != PREDICT_MODE) {

                 int32_t mv = pack16to32(mx, my);

 
                 if (part_height == 8 && i < 8) {

                     AV_WN32A(h->mv_cache[dir][scan8[k] + 1 * 8], mv);

                     if (part_width == 8 && j < 8)
                         AV_WN32A(h->mv_cache[dir][scan8[k] + 1 + 1 * 8], mv);

                 }

                 if (part_width == 8 && j < 8)

                     AV_WN32A(h->mv_cache[dir][scan8[k] + 1], mv);

                 if (part_width == 4 || part_height == 4)

                     AV_WN32A(h->mv_cache[dir][scan8[k]], mv);

             }
 
             /* write back motion vectors */

             fill_rectangle(h->cur_pic.f.motion_val[dir][b_xy],

                            part_width >> 2, part_height >> 2, h->b_stride,
                            pack16to32(mx, my), 4);

         }

     return 0;

 }
 

 static int svq3_decode_mb(SVQ3Context *s, unsigned int mb_type)

 {

     H264Context *h = &s->h;

     int i, j, k, m, dir, mode;
     int cbp = 0;
     uint32_t vlc;
     int8_t *top, *left;

     const int mb_xy         = h->mb_xy;

     const int b_xy          = 4 * h->mb_x + 4 * h->mb_y * h->b_stride;

     h->top_samples_available      = (h->mb_y == 0) ? 0x33FF : 0xFFFF;
     h->left_samples_available     = (h->mb_x == 0) ? 0x5F5F : 0xFFFF;

     h->topright_samples_available = 0xFFFF;
 
     if (mb_type == 0) {           /* SKIP */

         if (h->pict_type == AV_PICTURE_TYPE_P ||
             s->next_pic->f.mb_type[mb_xy] == -1) {
             svq3_mc_dir_part(s, 16 * h->mb_x, 16 * h->mb_y, 16, 16,

                              0, 0, 0, 0, 0, 0);

             if (h->pict_type == AV_PICTURE_TYPE_B)
                 svq3_mc_dir_part(s, 16 * h->mb_x, 16 * h->mb_y, 16, 16,

                                  0, 0, 0, 0, 1, 1);

 
             mb_type = MB_TYPE_SKIP;
         } else {

             mb_type = FFMIN(s->next_pic->f.mb_type[mb_xy], 6);
             if (svq3_mc_dir(s, mb_type, PREDICT_MODE, 0, 0) < 0)

                 return -1;

             if (svq3_mc_dir(s, mb_type, PREDICT_MODE, 1, 1) < 0)

                 return -1;

             mb_type = MB_TYPE_16x16;

         }

     } else if (mb_type < 8) {     /* INTER */

         if (s->thirdpel_flag && s->halfpel_flag == !get_bits1(&h->gb))

             mode = THIRDPEL_MODE;

         else if (s->halfpel_flag &&
                  s->thirdpel_flag == !get_bits1(&h->gb))

             mode = HALFPEL_MODE;

         else

             mode = FULLPEL_MODE;

         /* fill caches */
         /* note ref_cache should contain here:

          *  ????????
          *  ???11111
          *  N??11111
          *  N??11111
          *  N??11111
          */

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

             if (h->mb_x > 0 && h->intra4x4_pred_mode[h->mb2br_xy[mb_xy - 1] + 6] != -1) {

                 for (i = 0; i < 4; i++)
                     AV_COPY32(h->mv_cache[m][scan8[0] - 1 + i * 8],

                               h->cur_pic.f.motion_val[m][b_xy - 1 + i * h->b_stride]);

             } else {

                 for (i = 0; i < 4; i++)
                     AV_ZERO32(h->mv_cache[m][scan8[0] - 1 + i * 8]);

             }

             if (h->mb_y > 0) {

                 memcpy(h->mv_cache[m][scan8[0] - 1 * 8],

                        h->cur_pic.f.motion_val[m][b_xy - h->b_stride],

                        4 * 2 * sizeof(int16_t));
                 memset(&h->ref_cache[m][scan8[0] - 1 * 8],

                        (h->intra4x4_pred_mode[h->mb2br_xy[mb_xy - h->mb_stride]] == -1) ? PART_NOT_AVAILABLE : 1, 4);

                 if (h->mb_x < h->mb_width - 1) {

                     AV_COPY32(h->mv_cache[m][scan8[0] + 4 - 1 * 8],

                               h->cur_pic.f.motion_val[m][b_xy - h->b_stride + 4]);

                     h->ref_cache[m][scan8[0] + 4 - 1 * 8] =

                         (h->intra4x4_pred_mode[h->mb2br_xy[mb_xy - h->mb_stride + 1] + 6] == -1 ||
                          h->intra4x4_pred_mode[h->mb2br_xy[mb_xy - h->mb_stride]] == -1) ? PART_NOT_AVAILABLE : 1;

                 } else
                     h->ref_cache[m][scan8[0] + 4 - 1 * 8] = PART_NOT_AVAILABLE;

                 if (h->mb_x > 0) {

                     AV_COPY32(h->mv_cache[m][scan8[0] - 1 - 1 * 8],

                               h->cur_pic.f.motion_val[m][b_xy - h->b_stride - 1]);

                     h->ref_cache[m][scan8[0] - 1 - 1 * 8] =

                         (h->intra4x4_pred_mode[h->mb2br_xy[mb_xy - h->mb_stride - 1] + 3] == -1) ? PART_NOT_AVAILABLE : 1;

                 } else
                     h->ref_cache[m][scan8[0] - 1 - 1 * 8] = PART_NOT_AVAILABLE;
             } else
                 memset(&h->ref_cache[m][scan8[0] - 1 * 8 - 1],
                        PART_NOT_AVAILABLE, 8);

             if (h->pict_type != AV_PICTURE_TYPE_B)

                 break;

         }

         /* decode motion vector(s) and form prediction(s) */

         if (h->pict_type == AV_PICTURE_TYPE_P) {
             if (svq3_mc_dir(s, mb_type - 1, mode, 0, 0) < 0)

                 return -1;

         } else {        /* AV_PICTURE_TYPE_B */

             if (mb_type != 2) {

                 if (svq3_mc_dir(s, 0, mode, 0, 0) < 0)

                     return -1;
             } else {

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

                     memset(h->cur_pic.f.motion_val[0][b_xy + i * h->b_stride],

                            0, 4 * 2 * sizeof(int16_t));

             }
             if (mb_type != 1) {

                 if (svq3_mc_dir(s, 0, mode, 1, mb_type == 3) < 0)

                     return -1;
             } else {

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

                     memset(h->cur_pic.f.motion_val[1][b_xy + i * h->b_stride],

                            0, 4 * 2 * sizeof(int16_t));

             }

         }

         mb_type = MB_TYPE_16x16;
     } else if (mb_type == 8 || mb_type == 33) {   /* INTRA4x4 */

         memset(h->intra4x4_pred_mode_cache, -1, 8 * 5 * sizeof(int8_t));

 
         if (mb_type == 8) {

             if (h->mb_x > 0) {

                 for (i = 0; i < 4; i++)
                     h->intra4x4_pred_mode_cache[scan8[0] - 1 + i * 8] = h->intra4x4_pred_mode[h->mb2br_xy[mb_xy - 1] + 6 - i];
                 if (h->intra4x4_pred_mode_cache[scan8[0] - 1] == -1)

                     h->left_samples_available = 0x5F5F;
             }

             if (h->mb_y > 0) {
                 h->intra4x4_pred_mode_cache[4 + 8 * 0] = h->intra4x4_pred_mode[h->mb2br_xy[mb_xy - h->mb_stride] + 0];
                 h->intra4x4_pred_mode_cache[5 + 8 * 0] = h->intra4x4_pred_mode[h->mb2br_xy[mb_xy - h->mb_stride] + 1];
                 h->intra4x4_pred_mode_cache[6 + 8 * 0] = h->intra4x4_pred_mode[h->mb2br_xy[mb_xy - h->mb_stride] + 2];
                 h->intra4x4_pred_mode_cache[7 + 8 * 0] = h->intra4x4_pred_mode[h->mb2br_xy[mb_xy - h->mb_stride] + 3];

                 if (h->intra4x4_pred_mode_cache[4 + 8 * 0] == -1)

                     h->top_samples_available = 0x33FF;
             }
 
             /* decode prediction codes for luma blocks */

             for (i = 0; i < 16; i += 2) {

                 vlc = svq3_get_ue_golomb(&h->gb);

                 if (vlc >= 25U) {

                     av_log(h->avctx, AV_LOG_ERROR, "luma prediction:%d\n", vlc);

                     return -1;
                 }
 

                 left = &h->intra4x4_pred_mode_cache[scan8[i] - 1];
                 top  = &h->intra4x4_pred_mode_cache[scan8[i] - 8];

 
                 left[1] = svq3_pred_1[top[0] + 1][left[0] + 1][svq3_pred_0[vlc][0]];
                 left[2] = svq3_pred_1[top[1] + 1][left[1] + 1][svq3_pred_0[vlc][1]];
 

                 if (left[1] == -1 || left[2] == -1) {

                     av_log(h->avctx, AV_LOG_ERROR, "weird prediction\n");

                     return -1;
                 }
             }
         } else {    /* mb_type == 33, DC_128_PRED block type */

             for (i = 0; i < 4; i++)
                 memset(&h->intra4x4_pred_mode_cache[scan8[0] + 8 * i], DC_PRED, 4);

         }

         write_back_intra_pred_mode(h);

         if (mb_type == 8) {

             ff_h264_check_intra4x4_pred_mode(h);

             h->top_samples_available  = (h->mb_y == 0) ? 0x33FF : 0xFFFF;
             h->left_samples_available = (h->mb_x == 0) ? 0x5F5F : 0xFFFF;

         } else {

             for (i = 0; i < 4; i++)
                 memset(&h->intra4x4_pred_mode_cache[scan8[0] + 8 * i], DC_128_PRED, 4);

             h->top_samples_available  = 0x33FF;
             h->left_samples_available = 0x5F5F;
         }

         mb_type = MB_TYPE_INTRA4x4;
     } else {                      /* INTRA16x16 */
         dir = i_mb_type_info[mb_type - 8].pred_mode;

         dir = (dir >> 1) ^ 3 * (dir & 1) ^ 1;

         if ((h->intra16x16_pred_mode = ff_h264_check_intra_pred_mode(h, dir, 0)) == -1) {

             av_log(h->avctx, AV_LOG_ERROR, "check_intra_pred_mode = -1\n");

             return -1;
         }

         cbp     = i_mb_type_info[mb_type - 8].cbp;

         mb_type = MB_TYPE_INTRA16x16;

     }

     if (!IS_INTER(mb_type) && h->pict_type != AV_PICTURE_TYPE_I) {

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

             memset(h->cur_pic.f.motion_val[0][b_xy + i * h->b_stride],

                    0, 4 * 2 * sizeof(int16_t));

         if (h->pict_type == AV_PICTURE_TYPE_B) {

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

                 memset(h->cur_pic.f.motion_val[1][b_xy + i * h->b_stride],

                        0, 4 * 2 * sizeof(int16_t));

         }

     }

     if (!IS_INTRA4x4(mb_type)) {

         memset(h->intra4x4_pred_mode + h->mb2br_xy[mb_xy], DC_PRED, 8);

     }

     if (!IS_SKIP(mb_type) || h->pict_type == AV_PICTURE_TYPE_B) {

         memset(h->non_zero_count_cache + 8, 0, 14 * 8 * sizeof(uint8_t));

     }

     if (!IS_INTRA16x16(mb_type) &&

         (!IS_SKIP(mb_type) || h->pict_type == AV_PICTURE_TYPE_B)) {

         if ((vlc = svq3_get_ue_golomb(&h->gb)) >= 48U){

             av_log(h->avctx, AV_LOG_ERROR, "cbp_vlc=%d\n", vlc);

             return -1;
         }

         cbp = IS_INTRA(mb_type) ? golomb_to_intra4x4_cbp[vlc]
                                 : golomb_to_inter_cbp[vlc];

     }

     if (IS_INTRA16x16(mb_type) ||

         (h->pict_type != AV_PICTURE_TYPE_I && s->adaptive_quant && cbp)) {
         h->qscale += svq3_get_se_golomb(&h->gb);

         if (h->qscale > 31u) {
             av_log(h->avctx, AV_LOG_ERROR, "qscale:%d\n", h->qscale);

             return -1;
         }

     }

     if (IS_INTRA16x16(mb_type)) {

         AV_ZERO128(h->mb_luma_dc[0] + 0);
         AV_ZERO128(h->mb_luma_dc[0] + 8);

         if (svq3_decode_block(&h->gb, h->mb_luma_dc[0], 0, 1)) {
             av_log(h->avctx, AV_LOG_ERROR,

                    "error while decoding intra luma dc\n");

             return -1;

         }

     }

     if (cbp) {
         const int index = IS_INTRA16x16(mb_type) ? 1 : 0;

         const int type  = ((h->qscale < 24 && IS_INTRA4x4(mb_type)) ? 2 : 1);

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

             if ((cbp & (1 << i))) {
                 for (j = 0; j < 4; j++) {

                     k = index ? (1 * (j & 1) + 2 * (i & 1) +
                                  2 * (j & 2) + 4 * (i & 2))
                               : (4 * i + j);
                     h->non_zero_count_cache[scan8[k]] = 1;
 

                     if (svq3_decode_block(&h->gb, &h->mb[16 * k], index, type)) {
                         av_log(h->avctx, AV_LOG_ERROR,

                                "error while decoding block\n");

                         return -1;
                     }
                 }
             }

         if ((cbp & 0x30)) {

             for (i = 1; i < 3; ++i)

                 if (svq3_decode_block(&h->gb, &h->mb[16 * 16 * i], 0, 3)) {
                     av_log(h->avctx, AV_LOG_ERROR,

                            "error while decoding chroma dc block\n");
                     return -1;
                 }

 
             if ((cbp & 0x20)) {

                 for (i = 1; i < 3; i++) {
                     for (j = 0; j < 4; j++) {

                         k                                 = 16 * i + j;
                         h->non_zero_count_cache[scan8[k]] = 1;

                         if (svq3_decode_block(&h->gb, &h->mb[16 * k], 1, 1)) {
                             av_log(h->avctx, AV_LOG_ERROR,

                                    "error while decoding chroma ac block\n");

                             return -1;
                         }

                     }
                 }
             }

         }

     }
 

     h->cbp                              = cbp;

     h->cur_pic.f.mb_type[mb_xy] = mb_type;

     if (IS_INTRA(mb_type))

         h->chroma_pred_mode = ff_h264_check_intra_pred_mode(h, DC_PRED8x8, 1);

     return 0;

 }
 

 static int svq3_decode_slice_header(AVCodecContext *avctx)

 {

     SVQ3Context *s = avctx->priv_data;
     H264Context *h    = &s->h;

     const int mb_xy   = h->mb_xy;

     int i, header;

     unsigned slice_id;

     header = get_bits(&h->gb, 8);

     if (((header & 0x9F) != 1 && (header & 0x9F) != 2) || (header & 0x60) == 0) {
         /* TODO: what? */

         av_log(avctx, AV_LOG_ERROR, "unsupported slice header (%02X)\n", header);

         return -1;
     } else {

         int length = header >> 5 & 3;

         s->next_slice_index = get_bits_count(&h->gb) +
                               8 * show_bits(&h->gb, 8 * length) +
                               8 * length;

         if (s->next_slice_index > h->gb.size_in_bits) {

             av_log(avctx, AV_LOG_ERROR, "slice after bitstream end\n");

             return -1;

         }

         h->gb.size_in_bits = s->next_slice_index - 8 * (length - 1);
         skip_bits(&h->gb, 8);

         if (s->watermark_key) {
             uint32_t header = AV_RL32(&h->gb.buffer[(get_bits_count(&h->gb) >> 3) + 1]);
             AV_WL32(&h->gb.buffer[(get_bits_count(&h->gb) >> 3) + 1],
                     header ^ s->watermark_key);

         }
         if (length > 0) {

             memcpy((uint8_t *) &h->gb.buffer[get_bits_count(&h->gb) >> 3],
                    &h->gb.buffer[h->gb.size_in_bits >> 3], length - 1);

         }

         skip_bits_long(&h->gb, 0);

     }
 

     if ((slice_id = svq3_get_ue_golomb(&h->gb)) >= 3) {
         av_log(h->avctx, AV_LOG_ERROR, "illegal slice type %d \n", slice_id);

         return -1;
     }

     h->slice_type = golomb_to_pict_type[slice_id];

     if ((header & 0x9F) == 2) {

         i              = (h->mb_num < 64) ? 6 : (1 + av_log2(h->mb_num - 1));
         h->mb_skip_run = get_bits(&h->gb, i) -
                          (h->mb_y * h->mb_width + h->mb_x);

     } else {

         skip_bits1(&h->gb);
         h->mb_skip_run = 0;

     }

     h->slice_num      = get_bits(&h->gb, 8);
     h->qscale         = get_bits(&h->gb, 5);
     s->adaptive_quant = get_bits1(&h->gb);

     /* unknown fields */

     skip_bits1(&h->gb);

     if (s->unknown_flag)
         skip_bits1(&h->gb);

     skip_bits1(&h->gb);
     skip_bits(&h->gb, 2);

     while (get_bits1(&h->gb))
         skip_bits(&h->gb, 8);

     /* reset intra predictors and invalidate motion vector references */

     if (h->mb_x > 0) {

         memset(h->intra4x4_pred_mode + h->mb2br_xy[mb_xy - 1] + 3,
                -1, 4 * sizeof(int8_t));

         memset(h->intra4x4_pred_mode + h->mb2br_xy[mb_xy - h->mb_x],
                -1, 8 * sizeof(int8_t) * h->mb_x);

     }

     if (h->mb_y > 0) {
         memset(h->intra4x4_pred_mode + h->mb2br_xy[mb_xy - h->mb_stride],
                -1, 8 * sizeof(int8_t) * (h->mb_width - h->mb_x));

         if (h->mb_x > 0)
             h->intra4x4_pred_mode[h->mb2br_xy[mb_xy - h->mb_stride - 1] + 3] = -1;

     }
 

     return 0;

 }
 

 static av_cold int svq3_decode_init(AVCodecContext *avctx)

 {

     SVQ3Context *s = avctx->priv_data;
     H264Context *h = &s->h;

     int m;

     unsigned char *extradata;

     unsigned char *extradata_end;

     unsigned int size;

     int marker_found = 0;

     s->cur_pic  = av_mallocz(sizeof(*s->cur_pic));
     s->last_pic = av_mallocz(sizeof(*s->last_pic));
     s->next_pic = av_mallocz(sizeof(*s->next_pic));
     if (!s->next_pic || !s->last_pic || !s->cur_pic) {
         av_freep(&s->cur_pic);
         av_freep(&s->last_pic);
         av_freep(&s->next_pic);
         return AVERROR(ENOMEM);
     }
 

     if (ff_h264_decode_init(avctx) < 0)

         return -1;
 

     h->flags           = avctx->flags;

     h->is_complex      = 1;

     h->sps.chroma_format_idc = 1;

     h->picture_structure = PICT_FRAME;

     avctx->pix_fmt     = avctx->codec->pix_fmts[0];

     h->chroma_qp[0] = h->chroma_qp[1] = 4;

     h->chroma_x_shift = h->chroma_y_shift = 1;

     s->halfpel_flag  = 1;
     s->thirdpel_flag = 1;
     s->unknown_flag  = 0;

 
     /* prowl for the "SEQH" marker in the extradata */
     extradata     = (unsigned char *)avctx->extradata;
     extradata_end = avctx->extradata + avctx->extradata_size;
     if (extradata) {
         for (m = 0; m + 8 < avctx->extradata_size; m++) {
             if (!memcmp(extradata, "SEQH", 4)) {
                 marker_found = 1;
                 break;

             }

             extradata++;

         }

     }

     /* if a match was found, parse the extra data */
     if (marker_found) {
         GetBitContext gb;
         int frame_size_code;
 
         size = AV_RB32(&extradata[4]);
         if (size > extradata_end - extradata - 8)
             return AVERROR_INVALIDDATA;
         init_get_bits(&gb, extradata + 8, size * 8);
 
         /* 'frame size code' and optional 'width, height' */
         frame_size_code = get_bits(&gb, 3);
         switch (frame_size_code) {
         case 0:
             avctx->width  = 160;
             avctx->height = 120;
             break;
         case 1:
             avctx->width  = 128;
             avctx->height =  96;
             break;
         case 2:
             avctx->width  = 176;
             avctx->height = 144;
             break;
         case 3:
             avctx->width  = 352;
             avctx->height = 288;
             break;
         case 4:
             avctx->width  = 704;
             avctx->height = 576;
             break;
         case 5:
             avctx->width  = 240;
             avctx->height = 180;
             break;
         case 6:
             avctx->width  = 320;
             avctx->height = 240;
             break;
         case 7:
             avctx->width  = get_bits(&gb, 12);
             avctx->height = get_bits(&gb, 12);
             break;
         }

         s->halfpel_flag  = get_bits1(&gb);
         s->thirdpel_flag = get_bits1(&gb);

         /* unknown fields */
         skip_bits1(&gb);
         skip_bits1(&gb);
         skip_bits1(&gb);
         skip_bits1(&gb);

         h->low_delay = get_bits1(&gb);

         /* unknown field */
         skip_bits1(&gb);

         while (get_bits1(&gb))
             skip_bits(&gb, 8);

         s->unknown_flag  = get_bits1(&gb);
         avctx->has_b_frames = !h->low_delay;
         if (s->unknown_flag) {

 #if CONFIG_ZLIB

             unsigned watermark_width  = svq3_get_ue_golomb(&gb);
             unsigned watermark_height = svq3_get_ue_golomb(&gb);
             int u1                    = svq3_get_ue_golomb(&gb);
             int u2                    = get_bits(&gb, 8);
             int u3                    = get_bits(&gb, 2);
             int u4                    = svq3_get_ue_golomb(&gb);
             unsigned long buf_len     = watermark_width *
                                         watermark_height * 4;
             int offset                = get_bits_count(&gb) + 7 >> 3;
             uint8_t *buf;
 

             if (watermark_height <= 0 || (uint64_t)watermark_width*4 > UINT_MAX/watermark_height)

                 return -1;

             buf = av_malloc(buf_len);
             av_log(avctx, AV_LOG_DEBUG, "watermark size: %dx%d\n",
                    watermark_width, watermark_height);
             av_log(avctx, AV_LOG_DEBUG,
                    "u1: %x u2: %x u3: %x compressed data size: %d offset: %d\n",
                    u1, u2, u3, u4, offset);
             if (uncompress(buf, &buf_len, extradata + 8 + offset,
                            size - offset) != Z_OK) {

                 av_log(avctx, AV_LOG_ERROR,

                        "could not uncompress watermark logo\n");
                 av_free(buf);

                 return -1;
             }

             s->watermark_key = ff_svq1_packet_checksum(buf, buf_len, 0);
             s->watermark_key = s->watermark_key << 16 | s->watermark_key;

             av_log(avctx, AV_LOG_DEBUG,

                    "watermark key %#x\n", s->watermark_key);

             av_free(buf);
 #else
             av_log(avctx, AV_LOG_ERROR,
                    "this svq3 file contains watermark which need zlib support compiled in\n");
             return -1;
 #endif

         }

     }

     h->width  = avctx->width;
     h->height = avctx->height;
     h->mb_width  = (h->width + 15) / 16;
     h->mb_height = (h->height + 15) / 16;
     h->mb_stride = h->mb_width + 1;
     h->mb_num    = h->mb_width * h->mb_height;
     h->b_stride = 4 * h->mb_width;
     s->h_edge_pos = h->mb_width * 16;
     s->v_edge_pos = h->mb_height * 16;

     if (ff_h264_alloc_tables(h) < 0) {
         av_log(avctx, AV_LOG_ERROR, "svq3 memory allocation failed\n");
         return AVERROR(ENOMEM);

     }

     return 0;
 }
 

 static int get_buffer(AVCodecContext *avctx, Picture *pic)
 {
     SVQ3Context *s = avctx->priv_data;
     H264Context *h = &s->h;
     const int big_mb_num    = h->mb_stride * (h->mb_height + 1) + 1;
     const int mb_array_size = h->mb_stride * h->mb_height;
     const int b4_stride     = h->mb_width * 4 + 1;
     const int b4_array_size = b4_stride * h->mb_height * 4;
     int ret;
 
     if (!pic->motion_val_base[0]) {
         int i;
 
         pic->mb_type_base = av_mallocz((big_mb_num + h->mb_stride) * sizeof(uint32_t));
         if (!pic->mb_type_base)
             return AVERROR(ENOMEM);
         pic->f.mb_type = pic->mb_type_base + 2 * h->mb_stride + 1;
 
         for (i = 0; i < 2; i++) {
             pic->motion_val_base[i] = av_mallocz(2 * (b4_array_size + 4) * sizeof(int16_t));
             pic->f.ref_index[i]     = av_mallocz(4 * mb_array_size);
             if (!pic->motion_val_base[i] || !pic->f.ref_index[i])
                 return AVERROR(ENOMEM);
 
             pic->f.motion_val[i] = pic->motion_val_base[i] + 4;
         }
     }
     pic->f.motion_subsample_log2 = 2;
     pic->f.reference = !(h->pict_type == AV_PICTURE_TYPE_B);
 
     ret = ff_get_buffer(avctx, &pic->f);

     if (!h->edge_emu_buffer) {
         h->edge_emu_buffer = av_mallocz(pic->f.linesize[0] * 17);
         if (!h->edge_emu_buffer)
             return AVERROR(ENOMEM);
     }

 
     h->linesize   = pic->f.linesize[0];
     h->uvlinesize = pic->f.linesize[1];
 
     return ret;
 }
 

 static int svq3_decode_frame(AVCodecContext *avctx, void *data,

                              int *got_frame, AVPacket *avpkt)

 {

     SVQ3Context *s     = avctx->priv_data;
     H264Context *h     = &s->h;

     int buf_size       = avpkt->size;

     int left;

     uint8_t *buf;

     int ret, m, i;

     /* special case for last picture */
     if (buf_size == 0) {

         if (s->next_pic->f.data[0] && !h->low_delay && !s->last_frame_output) {
             *(AVFrame *) data   = s->next_pic->f;
             s->last_frame_output = 1;

             *got_frame          = 1;

         }
         return 0;

     }

     h->mb_x = h->mb_y = h->mb_xy = 0;

     if (s->watermark_key) {
         av_fast_malloc(&s->buf, &s->buf_size,

                        buf_size+FF_INPUT_BUFFER_PADDING_SIZE);

         if (!s->buf)

             return AVERROR(ENOMEM);

         memcpy(s->buf, avpkt->data, buf_size);
         buf = s->buf;

     } else {
         buf = avpkt->data;
     }
 

     init_get_bits(&h->gb, buf, 8 * buf_size);

     if (svq3_decode_slice_header(avctx))

         return -1;

     h->pict_type = h->slice_type;

     if (h->pict_type != AV_PICTURE_TYPE_B)
         FFSWAP(Picture*, s->next_pic, s->last_pic);
 
     if (s->cur_pic->f.data[0])
         avctx->release_buffer(avctx, &s->cur_pic->f);

     /* for skipping the frame */

     s->cur_pic->f.pict_type = h->pict_type;
     s->cur_pic->f.key_frame = (h->pict_type == AV_PICTURE_TYPE_I);

     ret = get_buffer(avctx, s->cur_pic);
     if (ret < 0)
         return ret;
 
     h->cur_pic_ptr = s->cur_pic;
     h->cur_pic     = *s->cur_pic;
 
     for (i = 0; i < 16; i++) {
         h->block_offset[i]           = (4 * ((scan8[i] - scan8[0]) & 7)) + 4 * h->linesize * ((scan8[i] - scan8[0]) >> 3);
         h->block_offset[48 + i]      = (4 * ((scan8[i] - scan8[0]) & 7)) + 8 * h->linesize * ((scan8[i] - scan8[0]) >> 3);
     }
     for (i = 0; i < 16; i++) {
         h->block_offset[16 + i]      =
         h->block_offset[32 + i]      = (4 * ((scan8[i] - scan8[0]) & 7)) + 4 * h->uvlinesize * ((scan8[i] - scan8[0]) >> 3);
         h->block_offset[48 + 16 + i] =
         h->block_offset[48 + 32 + i] = (4 * ((scan8[i] - scan8[0]) & 7)) + 8 * h->uvlinesize * ((scan8[i] - scan8[0]) >> 3);
     }
 
     if (h->pict_type != AV_PICTURE_TYPE_I) {
         if (!s->last_pic->f.data[0]) {
             av_log(avctx, AV_LOG_ERROR, "Missing reference frame.\n");
             ret = get_buffer(avctx, s->last_pic);
             if (ret < 0)
                 return ret;
             memset(s->last_pic->f.data[0], 0, avctx->height * s->last_pic->f.linesize[0]);
             memset(s->last_pic->f.data[1], 0x80, (avctx->height / 2) *
                    s->last_pic->f.linesize[1]);
             memset(s->last_pic->f.data[2], 0x80, (avctx->height / 2) *
                    s->last_pic->f.linesize[2]);
         }
 
         if (h->pict_type == AV_PICTURE_TYPE_B && !s->next_pic->f.data[0]) {
             av_log(avctx, AV_LOG_ERROR, "Missing reference frame.\n");
             ret = get_buffer(avctx, s->next_pic);
             if (ret < 0)
                 return ret;
             memset(s->next_pic->f.data[0], 0, avctx->height * s->next_pic->f.linesize[0]);
             memset(s->next_pic->f.data[1], 0x80, (avctx->height / 2) *
                    s->next_pic->f.linesize[1]);
             memset(s->next_pic->f.data[2], 0x80, (avctx->height / 2) *
                    s->next_pic->f.linesize[2]);
         }
     }
 
     if (avctx->debug & FF_DEBUG_PICT_INFO)
         av_log(h->avctx, AV_LOG_DEBUG,
                "%c hpel:%d, tpel:%d aqp:%d qp:%d, slice_num:%02X\n",
                av_get_picture_type_char(h->pict_type),
                s->halfpel_flag, s->thirdpel_flag,
                s->adaptive_quant, h->qscale, h->slice_num);
 
     if (avctx->skip_frame >= AVDISCARD_NONREF && h->pict_type == AV_PICTURE_TYPE_B ||
         avctx->skip_frame >= AVDISCARD_NONKEY && h->pict_type != AV_PICTURE_TYPE_I ||

         avctx->skip_frame >= AVDISCARD_ALL)

         return 0;
 
     if (s->next_p_frame_damaged) {

         if (h->pict_type == AV_PICTURE_TYPE_B)

             return 0;
         else
             s->next_p_frame_damaged = 0;
     }

     if (h->pict_type == AV_PICTURE_TYPE_B) {

         h->frame_num_offset = h->slice_num - h->prev_frame_num;

         if (h->frame_num_offset < 0)

             h->frame_num_offset += 256;

         if (h->frame_num_offset == 0 ||
             h->frame_num_offset >= h->prev_frame_num_offset) {

             av_log(h->avctx, AV_LOG_ERROR, "error in B-frame picture id\n");

             return -1;
         }
     } else {

         h->prev_frame_num        = h->frame_num;
         h->frame_num             = h->slice_num;

         h->prev_frame_num_offset = h->frame_num - h->prev_frame_num;

         if (h->prev_frame_num_offset < 0)

             h->prev_frame_num_offset += 256;

     }
 

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

         int i;

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

             int j;
             for (j = -1; j < 4; j++)

                 h->ref_cache[m][scan8[0] + 8 * i + j] = 1;

             if (i < 3)

                 h->ref_cache[m][scan8[0] + 8 * i + j] = PART_NOT_AVAILABLE;

         }

     }
 

     for (h->mb_y = 0; h->mb_y < h->mb_height; h->mb_y++) {
         for (h->mb_x = 0; h->mb_x < h->mb_width; h->mb_x++) {

             unsigned mb_type;

             h->mb_xy = h->mb_x + h->mb_y * h->mb_stride;

             if ((get_bits_count(&h->gb) + 7) >= h->gb.size_in_bits &&
                 ((get_bits_count(&h->gb) & 7) == 0 ||
                  show_bits(&h->gb, -get_bits_count(&h->gb) & 7) == 0)) {
                 skip_bits(&h->gb, s->next_slice_index - get_bits_count(&h->gb));
                 h->gb.size_in_bits = 8 * buf_size;

                 if (svq3_decode_slice_header(avctx))

                     return -1;

                 /* TODO: support s->mb_skip_run */
             }

             mb_type = svq3_get_ue_golomb(&h->gb);

             if (h->pict_type == AV_PICTURE_TYPE_I)

                 mb_type += 8;

             else if (h->pict_type == AV_PICTURE_TYPE_B && mb_type >= 4)

                 mb_type += 4;

             if (mb_type > 33 || svq3_decode_mb(s, mb_type)) {
                 av_log(h->avctx, AV_LOG_ERROR,
                        "error while decoding MB %d %d\n", h->mb_x, h->mb_y);

                 return -1;
             }

             if (mb_type != 0 || h->cbp)

                 ff_h264_hl_decode_mb(h);

             if (h->pict_type != AV_PICTURE_TYPE_B && !h->low_delay)
                 h->cur_pic.f.mb_type[h->mb_x + h->mb_y * h->mb_stride] =
                     (h->pict_type == AV_PICTURE_TYPE_P && mb_type < 8) ? (mb_type - 1) : -1;

         }

         ff_draw_horiz_band(avctx, NULL, s->cur_pic, s->last_pic->f.data[0] ? s->last_pic : NULL,
                            16 * h->mb_y, 16, h->picture_structure, 0, 0,

                            h->low_delay, h->mb_height * 16, h->mb_width * 16);

     }

     left = buf_size*8 - get_bits_count(&h->gb);

     if (h->mb_y != h->mb_height || h->mb_x != h->mb_width) {
         av_log(avctx, AV_LOG_INFO, "frame num %d incomplete pic x %d y %d left %d\n", avctx->frame_number, h->mb_y, h->mb_x, left);

         //av_hex_dump(stderr, buf+buf_size-8, 8);
     }
 
     if (left < 0) {
         av_log(avctx, AV_LOG_ERROR, "frame num %d left %d\n", avctx->frame_number, left);
         return -1;
     }
 

     if (h->pict_type == AV_PICTURE_TYPE_B || h->low_delay)
         *(AVFrame *)data = s->cur_pic->f;

     else

         *(AVFrame *)data = s->last_pic->f;

     /* Do not output the last pic after seeking. */

     if (s->last_pic->f.data[0] || h->low_delay)

         *got_frame = 1;

     if (h->pict_type != AV_PICTURE_TYPE_B) {
         FFSWAP(Picture*, s->cur_pic, s->next_pic);
     }
 

     return buf_size;

 }
 

 static void free_picture(AVCodecContext *avctx, Picture *pic)
 {
     int i;
     for (i = 0; i < 2; i++) {
         av_freep(&pic->motion_val_base[i]);
         av_freep(&pic->f.ref_index[i]);
     }
     av_freep(&pic->mb_type_base);
 
     if (pic->f.data[0])
         avctx->release_buffer(avctx, &pic->f);
     av_freep(&pic);
 }
 

 static int svq3_decode_end(AVCodecContext *avctx)
 {

     SVQ3Context *s = avctx->priv_data;
     H264Context *h = &s->h;

     free_picture(avctx, s->cur_pic);
     free_picture(avctx, s->next_pic);
     free_picture(avctx, s->last_pic);

     ff_h264_free_context(h);

     av_freep(&s->buf);
     s->buf_size = 0;

     av_freep(&h->edge_emu_buffer);

     return 0;
 }

 AVCodec ff_svq3_decoder = {

     .name           = "svq3",
     .type           = AVMEDIA_TYPE_VIDEO,

     .id             = AV_CODEC_ID_SVQ3,

     .priv_data_size = sizeof(SVQ3Context),
     .init           = svq3_decode_init,
     .close          = svq3_decode_end,
     .decode         = svq3_decode_frame,

     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND |
                       CODEC_CAP_DR1             |

                       CODEC_CAP_DELAY,
     .long_name      = NULL_IF_CONFIG_SMALL("Sorenson Vector Quantizer 3 / Sorenson Video 3 / SVQ3"),

     .pix_fmts       = (const enum AVPixelFormat[]) { AV_PIX_FMT_YUVJ420P,
                                                      AV_PIX_FMT_NONE},

 };