/*
  * Chinese AVS video (AVS1-P2, JiZhun profile) decoder.
  * Copyright (c) 2006  Stefan Gehrer <stefan.gehrer@gmx.de>
  *

  * 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

  */
 

 /**

  * @file

  * Chinese AVS video (AVS1-P2, JiZhun profile) decoder
  * @author Stefan Gehrer <stefan.gehrer@gmx.de>
  */
 

 #include "avcodec.h"

 #include "get_bits.h"

 #include "golomb.h"

 #include "h264chroma.h"

 #include "idctdsp.h"

 #include "internal.h"

 #include "mathops.h"

 #include "qpeldsp.h"

 #include "cavs.h"

 static const uint8_t alpha_tab[64] = {

      0,  0,  0,  0,  0,  0,  1,  1,  1,  1,  1,  2,  2,  2,  3,  3,
      4,  4,  5,  5,  6,  7,  8,  9, 10, 11, 12, 13, 15, 16, 18, 20,
     22, 24, 26, 28, 30, 33, 33, 35, 35, 36, 37, 37, 39, 39, 42, 44,
     46, 48, 50, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64

 };
 
 static const uint8_t beta_tab[64] = {

      0,  0,  0,  0,  0,  0,  1,  1,  1,  1,  1,  1,  1,  2,  2,  2,
      2,  2,  3,  3,  3,  3,  4,  4,  4,  4,  5,  5,  5,  5,  6,  6,
      6,  7,  7,  7,  8,  8,  8,  9,  9, 10, 10, 11, 11, 12, 13, 14,
     15, 16, 17, 18, 19, 20, 21, 22, 23, 23, 24, 24, 25, 25, 26, 27

 };
 
 static const uint8_t tc_tab[64] = {

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

 };
 
 /** mark block as unavailable, i.e. out of picture

  *  or not yet decoded */

 static const cavs_vector un_mv = { 0, 0, 1, NOT_AVAIL };
 
 static const int8_t left_modifier_l[8] = {  0, -1,  6, -1, -1, 7, 6, 7 };
 static const int8_t top_modifier_l[8]  = { -1,  1,  5, -1, -1, 5, 7, 7 };
 static const int8_t left_modifier_c[7] = {  5, -1,  2, -1,  6, 5, 6 };
 static const int8_t top_modifier_c[7]  = {  4,  1, -1, -1,  4, 6, 6 };

 
 /*****************************************************************************
  *
  * in-loop deblocking filter
  *
  ****************************************************************************/
 

 static inline int get_bs(cavs_vector *mvP, cavs_vector *mvQ, int b)
 {
     if ((mvP->ref == REF_INTRA) || (mvQ->ref == REF_INTRA))

         return 2;

     if((abs(mvP->x - mvQ->x) >= 4) ||
        (abs(mvP->y - mvQ->y) >= 4) ||
        (mvP->ref != mvQ->ref))

         return 1;

     if (b) {

         mvP += MV_BWD_OFFS;
         mvQ += MV_BWD_OFFS;

         if((abs(mvP->x - mvQ->x) >= 4) ||
            (abs(mvP->y - mvQ->y) >= 4) ||
            (mvP->ref != mvQ->ref))

             return 1;
     }
     return 0;
 }
 

 #define SET_PARAMS                                                \

     alpha = alpha_tab[av_clip_uintp2(qp_avg + h->alpha_offset, 6)];  \
     beta  =  beta_tab[av_clip_uintp2(qp_avg + h->beta_offset,  6)];  \
     tc    =    tc_tab[av_clip_uintp2(qp_avg + h->alpha_offset, 6)];

 
 /**
  * in-loop deblocking filter for a single macroblock
  *
  * boundary strength (bs) mapping:

  *
  * --4---5--
  * 0   2   |
  * | 6 | 7 |
  * 1   3   |
  * ---------
  */

 void ff_cavs_filter(AVSContext *h, enum cavs_mb mb_type)
 {

     uint8_t bs[8];

     int qp_avg, alpha, beta, tc;
     int i;
 
     /* save un-deblocked lines */

     h->topleft_border_y = h->top_border_y[h->mbx * 16 + 15];
     h->topleft_border_u = h->top_border_u[h->mbx * 10 + 8];
     h->topleft_border_v = h->top_border_v[h->mbx * 10 + 8];
     memcpy(&h->top_border_y[h->mbx * 16],     h->cy + 15 * h->l_stride, 16);
     memcpy(&h->top_border_u[h->mbx * 10 + 1], h->cu +  7 * h->c_stride, 8);
     memcpy(&h->top_border_v[h->mbx * 10 + 1], h->cv +  7 * h->c_stride, 8);
     for (i = 0; i < 8; i++) {
         h->left_border_y[i * 2 + 1] = *(h->cy + 15 + (i * 2 + 0) * h->l_stride);
         h->left_border_y[i * 2 + 2] = *(h->cy + 15 + (i * 2 + 1) * h->l_stride);
         h->left_border_u[i + 1]     = *(h->cu + 7  +  i          * h->c_stride);
         h->left_border_v[i + 1]     = *(h->cv + 7  +  i          * h->c_stride);

     }

     if (!h->loop_filter_disable) {

         /* determine bs */

         if (mb_type == I_8X8)
             memset(bs, 2, 8);

         else {

             memset(bs, 0, 8);
             if (ff_cavs_partition_flags[mb_type] & SPLITV) {

                 bs[2] = get_bs(&h->mv[MV_FWD_X0], &h->mv[MV_FWD_X1], mb_type > P_8X8);
                 bs[3] = get_bs(&h->mv[MV_FWD_X2], &h->mv[MV_FWD_X3], mb_type > P_8X8);

             }

             if (ff_cavs_partition_flags[mb_type] & SPLITH) {

                 bs[6] = get_bs(&h->mv[MV_FWD_X0], &h->mv[MV_FWD_X2], mb_type > P_8X8);
                 bs[7] = get_bs(&h->mv[MV_FWD_X1], &h->mv[MV_FWD_X3], mb_type > P_8X8);
             }
             bs[0] = get_bs(&h->mv[MV_FWD_A1], &h->mv[MV_FWD_X0], mb_type > P_8X8);
             bs[1] = get_bs(&h->mv[MV_FWD_A3], &h->mv[MV_FWD_X2], mb_type > P_8X8);
             bs[4] = get_bs(&h->mv[MV_FWD_B2], &h->mv[MV_FWD_X0], mb_type > P_8X8);
             bs[5] = get_bs(&h->mv[MV_FWD_B3], &h->mv[MV_FWD_X1], mb_type > P_8X8);

         }

         if (AV_RN64(bs)) {
             if (h->flags & A_AVAIL) {

                 qp_avg = (h->qp + h->left_qp + 1) >> 1;
                 SET_PARAMS;

                 h->cdsp.cavs_filter_lv(h->cy, h->l_stride, alpha, beta, tc, bs[0], bs[1]);

                 qp_avg = (ff_cavs_chroma_qp[h->qp] + ff_cavs_chroma_qp[h->left_qp] + 1) >> 1;
                 SET_PARAMS;

                 h->cdsp.cavs_filter_cv(h->cu, h->c_stride, alpha, beta, tc, bs[0], bs[1]);
                 h->cdsp.cavs_filter_cv(h->cv, h->c_stride, alpha, beta, tc, bs[0], bs[1]);

             }
             qp_avg = h->qp;
             SET_PARAMS;

             h->cdsp.cavs_filter_lv(h->cy + 8,               h->l_stride, alpha, beta, tc, bs[2], bs[3]);
             h->cdsp.cavs_filter_lh(h->cy + 8 * h->l_stride, h->l_stride, alpha, beta, tc, bs[6], bs[7]);

             if (h->flags & B_AVAIL) {

                 qp_avg = (h->qp + h->top_qp[h->mbx] + 1) >> 1;
                 SET_PARAMS;

                 h->cdsp.cavs_filter_lh(h->cy, h->l_stride, alpha, beta, tc, bs[4], bs[5]);

                 qp_avg = (ff_cavs_chroma_qp[h->qp] + ff_cavs_chroma_qp[h->top_qp[h->mbx]] + 1) >> 1;
                 SET_PARAMS;

                 h->cdsp.cavs_filter_ch(h->cu, h->c_stride, alpha, beta, tc, bs[4], bs[5]);
                 h->cdsp.cavs_filter_ch(h->cv, h->c_stride, alpha, beta, tc, bs[4], bs[5]);

             }
         }
     }

     h->left_qp        = h->qp;

     h->top_qp[h->mbx] = h->qp;
 }
 
 #undef SET_PARAMS
 
 /*****************************************************************************
  *
  * spatial intra prediction
  *
  ****************************************************************************/
 

 void ff_cavs_load_intra_pred_luma(AVSContext *h, uint8_t *top,

                                   uint8_t **left, int block)
 {

     int i;
 

     switch (block) {

     case 0:

         *left               = h->left_border_y;

         h->left_border_y[0] = h->left_border_y[1];

         memset(&h->left_border_y[17], h->left_border_y[16], 9);
         memcpy(&top[1], &h->top_border_y[h->mbx * 16], 16);

         top[17] = top[16];

         top[0]  = top[1];
         if ((h->flags & A_AVAIL) && (h->flags & B_AVAIL))

             h->left_border_y[0] = top[0] = h->topleft_border_y;
         break;
     case 1:
         *left = h->intern_border_y;

         for (i = 0; i < 8; i++)
             h->intern_border_y[i + 1] = *(h->cy + 7 + i * h->l_stride);
         memset(&h->intern_border_y[9], h->intern_border_y[8], 9);

         h->intern_border_y[0] = h->intern_border_y[1];

         memcpy(&top[1], &h->top_border_y[h->mbx * 16 + 8], 8);
         if (h->flags & C_AVAIL)
             memcpy(&top[9], &h->top_border_y[(h->mbx + 1) * 16], 8);

         else

             memset(&top[9], top[8], 9);

         top[17] = top[16];

         top[0]  = top[1];
         if (h->flags & B_AVAIL)
             h->intern_border_y[0] = top[0] = h->top_border_y[h->mbx * 16 + 7];

         break;
     case 2:
         *left = &h->left_border_y[8];

         memcpy(&top[1], h->cy + 7 * h->l_stride, 16);

         top[17] = top[16];

         top[0]  = top[1];
         if (h->flags & A_AVAIL)

             top[0] = h->left_border_y[8];
         break;
     case 3:
         *left = &h->intern_border_y[8];

         for (i = 0; i < 8; i++)
             h->intern_border_y[i + 9] = *(h->cy + 7 + (i + 8) * h->l_stride);
         memset(&h->intern_border_y[17], h->intern_border_y[16], 9);
         memcpy(&top[0], h->cy + 7 + 7 * h->l_stride, 9);
         memset(&top[9], top[8], 9);

         break;
     }
 }
 

 void ff_cavs_load_intra_pred_chroma(AVSContext *h)
 {

     /* extend borders by one pixel */

     h->left_border_u[9]              = h->left_border_u[8];
     h->left_border_v[9]              = h->left_border_v[8];

     if(h->flags & C_AVAIL) {
         h->top_border_u[h->mbx*10 + 9] = h->top_border_u[h->mbx*10 + 11];
         h->top_border_v[h->mbx*10 + 9] = h->top_border_v[h->mbx*10 + 11];
     } else {
         h->top_border_u[h->mbx * 10 + 9] = h->top_border_u[h->mbx * 10 + 8];
         h->top_border_v[h->mbx * 10 + 9] = h->top_border_v[h->mbx * 10 + 8];
     }
     if((h->flags & A_AVAIL) && (h->flags & B_AVAIL)) {

         h->top_border_u[h->mbx * 10] = h->left_border_u[0] = h->topleft_border_u;
         h->top_border_v[h->mbx * 10] = h->left_border_v[0] = h->topleft_border_v;

     } else {

         h->left_border_u[0]          = h->left_border_u[1];
         h->left_border_v[0]          = h->left_border_v[1];

         h->top_border_u[h->mbx * 10] = h->top_border_u[h->mbx * 10 + 1];
         h->top_border_v[h->mbx * 10] = h->top_border_v[h->mbx * 10 + 1];

     }
 }
 

 static void intra_pred_vert(uint8_t *d, uint8_t *top, uint8_t *left, ptrdiff_t stride)

 {

     int y;

     uint64_t a = AV_RN64(&top[1]);

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

         *((uint64_t *)(d + y * stride)) = a;

 }
 

 static void intra_pred_horiz(uint8_t *d, uint8_t *top, uint8_t *left, ptrdiff_t stride)

 {

     int y;
     uint64_t a;

     for (y = 0; y < 8; y++) {
         a = left[y + 1] * 0x0101010101010101ULL;
         *((uint64_t *)(d + y * stride)) = a;

     }
 }
 

 static void intra_pred_dc_128(uint8_t *d, uint8_t *top, uint8_t *left, ptrdiff_t stride)

 {

     int y;
     uint64_t a = 0x8080808080808080ULL;

     for (y = 0; y < 8; y++)
         *((uint64_t *)(d + y * stride)) = a;

 }
 

 static void intra_pred_plane(uint8_t *d, uint8_t *top, uint8_t *left, ptrdiff_t stride)

 {
     int x, y, ia;

     int ih = 0;
     int iv = 0;

     const uint8_t *cm = ff_crop_tab + MAX_NEG_CROP;

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

         ih += (x + 1) *  (top[5 + x] -  top[3 - x]);

         iv += (x + 1) * (left[5 + x] - left[3 - x]);

     }

     ia = (top[8] + left[8]) << 4;
     ih = (17 * ih + 16) >> 5;
     iv = (17 * iv + 16) >> 5;
     for (y = 0; y < 8; y++)
         for (x = 0; x < 8; x++)
             d[y * stride + x] = cm[(ia + (x - 3) * ih + (y - 3) * iv + 16) >> 5];

 }
 

 #define LOWPASS(ARRAY, INDEX)                                           \

     ((ARRAY[(INDEX) - 1] + 2 * ARRAY[(INDEX)] + ARRAY[(INDEX) + 1] + 2) >> 2)

 static void intra_pred_lp(uint8_t *d, uint8_t *top, uint8_t *left, ptrdiff_t stride)

 {
     int x, y;
     for (y = 0; y < 8; y++)
         for (x = 0; x < 8; x++)
             d[y * stride + x] = (LOWPASS(top, x + 1) + LOWPASS(left, y + 1)) >> 1;

 }
 

 static void intra_pred_down_left(uint8_t *d, uint8_t *top, uint8_t *left, ptrdiff_t stride)

 {
     int x, y;
     for (y = 0; y < 8; y++)
         for (x = 0; x < 8; x++)
             d[y * stride + x] = (LOWPASS(top, x + y + 2) + LOWPASS(left, x + y + 2)) >> 1;

 }
 

 static void intra_pred_down_right(uint8_t *d, uint8_t *top, uint8_t *left, ptrdiff_t stride)

 {
     int x, y;
     for (y = 0; y < 8; y++)
         for (x = 0; x < 8; x++)
             if (x == y)
                 d[y * stride + x] = (left[1] + 2 * top[0] + top[1] + 2) >> 2;
             else if (x > y)
                 d[y * stride + x] = LOWPASS(top, x - y);

             else

                 d[y * stride + x] = LOWPASS(left, y - x);

 }
 

 static void intra_pred_lp_left(uint8_t *d, uint8_t *top, uint8_t *left, ptrdiff_t stride)

 {
     int x, y;
     for (y = 0; y < 8; y++)
         for (x = 0; x < 8; x++)
             d[y * stride + x] = LOWPASS(left, y + 1);

 }
 

 static void intra_pred_lp_top(uint8_t *d, uint8_t *top, uint8_t *left, ptrdiff_t stride)

 {
     int x, y;
     for (y = 0; y < 8; y++)
         for (x = 0; x < 8; x++)
             d[y * stride + x] = LOWPASS(top, x + 1);

 }
 
 #undef LOWPASS
 

 static inline void modify_pred(const int8_t *mod_table, int *mode)
 {
     *mode = mod_table[*mode];

     if (*mode < 0) {

         av_log(NULL, AV_LOG_ERROR, "Illegal intra prediction mode\n");
         *mode = 0;
     }
 }
 

 void ff_cavs_modify_mb_i(AVSContext *h, int *pred_mode_uv)
 {

     /* save pred modes before they get modified */

     h->pred_mode_Y[3]             = h->pred_mode_Y[5];
     h->pred_mode_Y[6]             = h->pred_mode_Y[8];

     h->top_pred_Y[h->mbx * 2 + 0] = h->pred_mode_Y[7];
     h->top_pred_Y[h->mbx * 2 + 1] = h->pred_mode_Y[8];

 
     /* modify pred modes according to availability of neighbour samples */

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

         modify_pred(left_modifier_l, &h->pred_mode_Y[4]);
         modify_pred(left_modifier_l, &h->pred_mode_Y[7]);
         modify_pred(left_modifier_c, pred_mode_uv);

     }

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

         modify_pred(top_modifier_l, &h->pred_mode_Y[4]);
         modify_pred(top_modifier_l, &h->pred_mode_Y[5]);
         modify_pred(top_modifier_c, pred_mode_uv);

     }
 }
 

 /*****************************************************************************
  *
  * motion compensation
  *
  ****************************************************************************/
 

 static inline void mc_dir_part(AVSContext *h, AVFrame *pic, int chroma_height,
                                int delta, int list, uint8_t *dest_y,
                                uint8_t *dest_cb, uint8_t *dest_cr,
                                int src_x_offset, int src_y_offset,
                                qpel_mc_func *qpix_op,
                                h264_chroma_mc_func chroma_op, cavs_vector *mv)

 {

     const int mx         = mv->x + src_x_offset * 8;
     const int my         = mv->y + src_y_offset * 8;

     const int luma_xy    = (mx & 3) + ((my & 3) << 2);
     uint8_t *src_y       = pic->data[0] + (mx >> 2) + (my >> 2) * h->l_stride;
     uint8_t *src_cb      = pic->data[1] + (mx >> 3) + (my >> 3) * h->c_stride;
     uint8_t *src_cr      = pic->data[2] + (mx >> 3) + (my >> 3) * h->c_stride;
     int extra_width      = 0;
     int extra_height     = extra_width;
     const int full_mx    = mx >> 2;
     const int full_my    = my >> 2;
     const int pic_width  = 16 * h->mb_width;
     const int pic_height = 16 * h->mb_height;
     int emu = 0;

     if (!pic->data[0])

         return;

     if (mx & 7)
         extra_width  -= 3;
     if (my & 7)
         extra_height -= 3;
 
     if (full_mx < 0 - extra_width ||
         full_my < 0 - extra_height ||
         full_mx + 16 /* FIXME */ > pic_width + extra_width ||
         full_my + 16 /* FIXME */ > pic_height + extra_height) {
         h->vdsp.emulated_edge_mc(h->edge_emu_buffer,

                                  src_y - 2 - 2 * h->l_stride,
                                  h->l_stride, h->l_stride,

                                  16 + 5, 16 + 5 /* FIXME */,
                                  full_mx - 2, full_my - 2,
                                  pic_width, pic_height);
         src_y = h->edge_emu_buffer + 2 + 2 * h->l_stride;

         emu   = 1;

     }
 

     // FIXME try variable height perhaps?
     qpix_op[luma_xy](dest_y, src_y, h->l_stride);

     if (emu) {
         h->vdsp.emulated_edge_mc(h->edge_emu_buffer, src_cb,

                                  h->c_stride, h->c_stride,

                                  9, 9 /* FIXME */,
                                  mx >> 3, my >> 3,
                                  pic_width >> 1, pic_height >> 1);
         src_cb = h->edge_emu_buffer;

     }

     chroma_op(dest_cb, src_cb, h->c_stride, chroma_height, mx & 7, my & 7);
 
     if (emu) {
         h->vdsp.emulated_edge_mc(h->edge_emu_buffer, src_cr,

                                  h->c_stride, h->c_stride,

                                  9, 9 /* FIXME */,
                                  mx >> 3, my >> 3,
                                  pic_width >> 1, pic_height >> 1);
         src_cr = h->edge_emu_buffer;

     }

     chroma_op(dest_cr, src_cr, h->c_stride, chroma_height, mx & 7, my & 7);

 }
 

 static inline void mc_part_std(AVSContext *h, int chroma_height, int delta,
                                uint8_t *dest_y,
                                uint8_t *dest_cb,
                                uint8_t *dest_cr,
                                int x_offset, int y_offset,
                                qpel_mc_func *qpix_put,
                                h264_chroma_mc_func chroma_put,
                                qpel_mc_func *qpix_avg,
                                h264_chroma_mc_func chroma_avg,
                                cavs_vector *mv)

 {

     qpel_mc_func *qpix_op =  qpix_put;
     h264_chroma_mc_func chroma_op = chroma_put;

     dest_y   += x_offset * 2 + y_offset * h->l_stride * 2;
     dest_cb  += x_offset     + y_offset * h->c_stride;
     dest_cr  += x_offset     + y_offset * h->c_stride;

     x_offset += 8 * h->mbx;
     y_offset += 8 * h->mby;

     if (mv->ref >= 0) {

         AVFrame *ref = h->DPB[mv->ref].f;

         mc_dir_part(h, ref, chroma_height, delta, 0,

                     dest_y, dest_cb, dest_cr, x_offset, y_offset,
                     qpix_op, chroma_op, mv);
 

         qpix_op   = qpix_avg;
         chroma_op = chroma_avg;

     }
 

     if ((mv + MV_BWD_OFFS)->ref >= 0) {

         AVFrame *ref = h->DPB[0].f;

         mc_dir_part(h, ref, chroma_height, delta, 1,

                     dest_y, dest_cb, dest_cr, x_offset, y_offset,

                     qpix_op, chroma_op, mv + MV_BWD_OFFS);

     }
 }
 

 void ff_cavs_inter(AVSContext *h, enum cavs_mb mb_type)
 {
     if (ff_cavs_partition_flags[mb_type] == 0) { // 16x16

         mc_part_std(h, 8, 0, h->cy, h->cu, h->cv, 0, 0,

                     h->cdsp.put_cavs_qpel_pixels_tab[0],
                     h->h264chroma.put_h264_chroma_pixels_tab[0],
                     h->cdsp.avg_cavs_qpel_pixels_tab[0],
                     h->h264chroma.avg_h264_chroma_pixels_tab[0],
                     &h->mv[MV_FWD_X0]);
     } else {

         mc_part_std(h, 4, 0, h->cy, h->cu, h->cv, 0, 0,

                     h->cdsp.put_cavs_qpel_pixels_tab[1],
                     h->h264chroma.put_h264_chroma_pixels_tab[1],
                     h->cdsp.avg_cavs_qpel_pixels_tab[1],
                     h->h264chroma.avg_h264_chroma_pixels_tab[1],
                     &h->mv[MV_FWD_X0]);

         mc_part_std(h, 4, 0, h->cy, h->cu, h->cv, 4, 0,

                     h->cdsp.put_cavs_qpel_pixels_tab[1],
                     h->h264chroma.put_h264_chroma_pixels_tab[1],
                     h->cdsp.avg_cavs_qpel_pixels_tab[1],
                     h->h264chroma.avg_h264_chroma_pixels_tab[1],
                     &h->mv[MV_FWD_X1]);

         mc_part_std(h, 4, 0, h->cy, h->cu, h->cv, 0, 4,

                     h->cdsp.put_cavs_qpel_pixels_tab[1],
                     h->h264chroma.put_h264_chroma_pixels_tab[1],
                     h->cdsp.avg_cavs_qpel_pixels_tab[1],
                     h->h264chroma.avg_h264_chroma_pixels_tab[1],
                     &h->mv[MV_FWD_X2]);

         mc_part_std(h, 4, 0, h->cy, h->cu, h->cv, 4, 4,

                     h->cdsp.put_cavs_qpel_pixels_tab[1],
                     h->h264chroma.put_h264_chroma_pixels_tab[1],
                     h->cdsp.avg_cavs_qpel_pixels_tab[1],
                     h->h264chroma.avg_h264_chroma_pixels_tab[1],
                     &h->mv[MV_FWD_X3]);

     }

 }
 
 /*****************************************************************************
  *
  * motion vector prediction
  *
  ****************************************************************************/
 

 static inline void scale_mv(AVSContext *h, int *d_x, int *d_y,
                             cavs_vector *src, int distp)
 {

     int64_t den = h->scale_den[FFMAX(src->ref, 0)];

     *d_x = (src->x * distp * den + 256 + FF_SIGNBIT(src->x)) >> 9;
     *d_y = (src->y * distp * den + 256 + FF_SIGNBIT(src->y)) >> 9;

 }
 

 static inline void mv_pred_median(AVSContext *h,
                                   cavs_vector *mvP,
                                   cavs_vector *mvA,
                                   cavs_vector *mvB,
                                   cavs_vector *mvC)
 {

     int ax, ay, bx, by, cx, cy;
     int len_ab, len_bc, len_ca, len_mid;
 
     /* scale candidates according to their temporal span */
     scale_mv(h, &ax, &ay, mvA, mvP->dist);
     scale_mv(h, &bx, &by, mvB, mvP->dist);
     scale_mv(h, &cx, &cy, mvC, mvP->dist);
     /* find the geometrical median of the three candidates */

     len_ab  = abs(ax - bx) + abs(ay - by);
     len_bc  = abs(bx - cx) + abs(by - cy);
     len_ca  = abs(cx - ax) + abs(cy - ay);

     len_mid = mid_pred(len_ab, len_bc, len_ca);

     if (len_mid == len_ab) {

         mvP->x = cx;
         mvP->y = cy;

     } else if (len_mid == len_bc) {

         mvP->x = ax;
         mvP->y = ay;
     } else {
         mvP->x = bx;
         mvP->y = by;
     }
 }
 

 void ff_cavs_mv(AVSContext *h, enum cavs_mv_loc nP, enum cavs_mv_loc nC,

                 enum cavs_mv_pred mode, enum cavs_block size, int ref)
 {

     cavs_vector *mvP = &h->mv[nP];
     cavs_vector *mvA = &h->mv[nP-1];
     cavs_vector *mvB = &h->mv[nP-4];
     cavs_vector *mvC = &h->mv[nC];
     const cavs_vector *mvP2 = NULL;

     mvP->ref  = ref;

     mvP->dist = h->dist[mvP->ref];

     if (mvC->ref == NOT_AVAIL || (nP == MV_FWD_X3) || (nP == MV_BWD_X3 ))

         mvC = &h->mv[nP - 5];  // set to top-left (mvD)

     if (mode == MV_PRED_PSKIP &&
         (mvA->ref == NOT_AVAIL ||
          mvB->ref == NOT_AVAIL ||
          (mvA->x | mvA->y | mvA->ref) == 0 ||
          (mvB->x | mvB->y | mvB->ref) == 0)) {

         mvP2 = &un_mv;

     /* if there is only one suitable candidate, take it */

     } else if (mvA->ref >= 0 && mvB->ref < 0  && mvC->ref < 0) {
         mvP2 = mvA;
     } else if (mvA->ref < 0  && mvB->ref >= 0 && mvC->ref < 0) {
         mvP2 = mvB;
     } else if (mvA->ref < 0  && mvB->ref < 0  && mvC->ref >= 0) {
         mvP2 = mvC;
     } else if (mode == MV_PRED_LEFT     && mvA->ref == ref) {
         mvP2 = mvA;
     } else if (mode == MV_PRED_TOP      && mvB->ref == ref) {
         mvP2 = mvB;
     } else if (mode == MV_PRED_TOPRIGHT && mvC->ref == ref) {
         mvP2 = mvC;

     }

     if (mvP2) {

         mvP->x = mvP2->x;
         mvP->y = mvP2->y;

     } else

         mv_pred_median(h, mvP, mvA, mvB, mvC);
 

     if (mode < MV_PRED_PSKIP) {

         int mx = get_se_golomb(&h->gb) + (unsigned)mvP->x;
         int my = get_se_golomb(&h->gb) + (unsigned)mvP->y;
 
         if (mx != (int16_t)mx || my != (int16_t)my) {
             av_log(h->avctx, AV_LOG_ERROR, "MV %d %d out of supported range\n", mx, my);
         } else {
             mvP->x = mx;
             mvP->y = my;
         }

     }

     set_mvs(mvP, size);

 }
 
 /*****************************************************************************
  *

  * macroblock level
  *
  ****************************************************************************/
 
 /**
  * initialise predictors for motion vectors and intra prediction
  */

 void ff_cavs_init_mb(AVSContext *h)
 {

     int i;
 
     /* copy predictors from top line (MB B and C) into cache */

     for (i = 0; i < 3; i++) {
         h->mv[MV_FWD_B2 + i] = h->top_mv[0][h->mbx * 2 + i];
         h->mv[MV_BWD_B2 + i] = h->top_mv[1][h->mbx * 2 + i];

     }

     h->pred_mode_Y[1] = h->top_pred_Y[h->mbx * 2 + 0];
     h->pred_mode_Y[2] = h->top_pred_Y[h->mbx * 2 + 1];

     /* clear top predictors if MB B is not available */

     if (!(h->flags & B_AVAIL)) {
         h->mv[MV_FWD_B2]  = un_mv;
         h->mv[MV_FWD_B3]  = un_mv;
         h->mv[MV_BWD_B2]  = un_mv;
         h->mv[MV_BWD_B3]  = un_mv;

         h->pred_mode_Y[1] = h->pred_mode_Y[2] = NOT_AVAIL;

         h->flags         &= ~(C_AVAIL | D_AVAIL);
     } else if (h->mbx) {

         h->flags |= D_AVAIL;
     }

     if (h->mbx == h->mb_width - 1) // MB C not available

         h->flags &= ~C_AVAIL;
     /* clear top-right predictors if MB C is not available */

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

         h->mv[MV_FWD_C2] = un_mv;
         h->mv[MV_BWD_C2] = un_mv;

     }
     /* clear top-left predictors if MB D is not available */

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

         h->mv[MV_FWD_D3] = un_mv;
         h->mv[MV_BWD_D3] = un_mv;

     }
 }
 
 /**
  * save predictors for later macroblocks and increase
  * macroblock address

  * @return 0 if end of frame is reached, 1 otherwise

  */

 int ff_cavs_next_mb(AVSContext *h)
 {

     int i;
 
     h->flags |= A_AVAIL;

     h->cy    += 16;
     h->cu    += 8;
     h->cv    += 8;

     /* copy mvs as predictors to the left */

     for (i = 0; i <= 20; i += 4)
         h->mv[i] = h->mv[i + 2];

     /* copy bottom mvs from cache to top line */

     h->top_mv[0][h->mbx * 2 + 0] = h->mv[MV_FWD_X2];
     h->top_mv[0][h->mbx * 2 + 1] = h->mv[MV_FWD_X3];
     h->top_mv[1][h->mbx * 2 + 0] = h->mv[MV_BWD_X2];
     h->top_mv[1][h->mbx * 2 + 1] = h->mv[MV_BWD_X3];

     /* next MB address */

     h->mbidx++;

     h->mbx++;

     if (h->mbx == h->mb_width) { // New mb line
         h->flags = B_AVAIL | C_AVAIL;

         /* clear left pred_modes */
         h->pred_mode_Y[3] = h->pred_mode_Y[6] = NOT_AVAIL;
         /* clear left mv predictors */

         for (i = 0; i <= 20; i += 4)

             h->mv[i] = un_mv;

         h->mbx = 0;
         h->mby++;
         /* re-calculate sample pointers */

         h->cy = h->cur.f->data[0] + h->mby * 16 * h->l_stride;

         h->cu = h->cur.f->data[1] + h->mby * 8 * h->c_stride;
         h->cv = h->cur.f->data[2] + h->mby * 8 * h->c_stride;
         if (h->mby == h->mb_height) { // Frame end

             return 0;
         }
     }
     return 1;
 }
 
 /*****************************************************************************
  *

  * frame level
  *
  ****************************************************************************/
 

 int ff_cavs_init_pic(AVSContext *h)

 {

     int i;
 
     /* clear some predictors */

     for (i = 0; i <= 20; i += 4)

         h->mv[i] = un_mv;

     h->mv[MV_BWD_X0] = ff_cavs_dir_mv;

     set_mvs(&h->mv[MV_BWD_X0], BLK_16X16);

     h->mv[MV_FWD_X0] = ff_cavs_dir_mv;

     set_mvs(&h->mv[MV_FWD_X0], BLK_16X16);
     h->pred_mode_Y[3] = h->pred_mode_Y[6] = NOT_AVAIL;

     h->cy             = h->cur.f->data[0];
     h->cu             = h->cur.f->data[1];
     h->cv             = h->cur.f->data[2];
     h->l_stride       = h->cur.f->linesize[0];
     h->c_stride       = h->cur.f->linesize[1];
     h->luma_scan[2]   = 8 * h->l_stride;
     h->luma_scan[3]   = 8 * h->l_stride + 8;
     h->mbx            = h->mby = h->mbidx = 0;
     h->flags          = 0;

 
     return 0;

 }
 
 /*****************************************************************************
  *
  * headers and interface
  *
  ****************************************************************************/
 

 /**
  * some predictions require data from the top-neighbouring macroblock.
  * this data has to be stored for one complete row of macroblocks
  * and this storage space is allocated here
  */

 int ff_cavs_init_top_lines(AVSContext *h)

 {

     /* alloc top line of predictors */

     h->top_qp       = av_mallocz(h->mb_width);

     h->top_mv[0]    = av_mallocz_array(h->mb_width * 2 + 1,  sizeof(cavs_vector));
     h->top_mv[1]    = av_mallocz_array(h->mb_width * 2 + 1,  sizeof(cavs_vector));
     h->top_pred_Y   = av_mallocz_array(h->mb_width * 2,  sizeof(*h->top_pred_Y));
     h->top_border_y = av_mallocz_array(h->mb_width + 1,  16);
     h->top_border_u = av_mallocz_array(h->mb_width,  10);
     h->top_border_v = av_mallocz_array(h->mb_width,  10);

 
     /* alloc space for co-located MVs and types */

     h->col_mv        = av_mallocz_array(h->mb_width * h->mb_height,
                                         4 * sizeof(cavs_vector));

     h->col_type_base = av_mallocz(h->mb_width * h->mb_height);
     h->block         = av_mallocz(64 * sizeof(int16_t));

 
     if (!h->top_qp || !h->top_mv[0] || !h->top_mv[1] || !h->top_pred_Y ||
         !h->top_border_y || !h->top_border_u || !h->top_border_v ||
         !h->col_mv || !h->col_type_base || !h->block) {
         av_freep(&h->top_qp);
         av_freep(&h->top_mv[0]);
         av_freep(&h->top_mv[1]);
         av_freep(&h->top_pred_Y);
         av_freep(&h->top_border_y);
         av_freep(&h->top_border_u);
         av_freep(&h->top_border_v);
         av_freep(&h->col_mv);
         av_freep(&h->col_type_base);
         av_freep(&h->block);
         return AVERROR(ENOMEM);
     }
     return 0;

 }
 

 av_cold int ff_cavs_init(AVCodecContext *avctx)
 {

     AVSContext *h = avctx->priv_data;

     ff_blockdsp_init(&h->bdsp, avctx);

     ff_h264chroma_init(&h->h264chroma, 8);

     ff_idctdsp_init(&h->idsp, avctx);

     ff_videodsp_init(&h->vdsp, 8);

     ff_cavsdsp_init(&h->cdsp, avctx);

     ff_init_scantable_permutation(h->idsp.idct_permutation,

                                   h->cdsp.idct_perm);

     ff_init_scantable(h->idsp.idct_permutation, &h->scantable, ff_zigzag_direct);

     h->avctx       = avctx;
     avctx->pix_fmt = AV_PIX_FMT_YUV420P;

     h->cur.f    = av_frame_alloc();
     h->DPB[0].f = av_frame_alloc();
     h->DPB[1].f = av_frame_alloc();

     if (!h->cur.f || !h->DPB[0].f || !h->DPB[1].f) {
         ff_cavs_end(avctx);
         return AVERROR(ENOMEM);
     }
 

     h->luma_scan[0]                     = 0;
     h->luma_scan[1]                     = 8;
     h->intra_pred_l[INTRA_L_VERT]       = intra_pred_vert;
     h->intra_pred_l[INTRA_L_HORIZ]      = intra_pred_horiz;
     h->intra_pred_l[INTRA_L_LP]         = intra_pred_lp;
     h->intra_pred_l[INTRA_L_DOWN_LEFT]  = intra_pred_down_left;

     h->intra_pred_l[INTRA_L_DOWN_RIGHT] = intra_pred_down_right;

     h->intra_pred_l[INTRA_L_LP_LEFT]    = intra_pred_lp_left;
     h->intra_pred_l[INTRA_L_LP_TOP]     = intra_pred_lp_top;
     h->intra_pred_l[INTRA_L_DC_128]     = intra_pred_dc_128;
     h->intra_pred_c[INTRA_C_LP]         = intra_pred_lp;
     h->intra_pred_c[INTRA_C_HORIZ]      = intra_pred_horiz;
     h->intra_pred_c[INTRA_C_VERT]       = intra_pred_vert;
     h->intra_pred_c[INTRA_C_PLANE]      = intra_pred_plane;
     h->intra_pred_c[INTRA_C_LP_LEFT]    = intra_pred_lp_left;
     h->intra_pred_c[INTRA_C_LP_TOP]     = intra_pred_lp_top;
     h->intra_pred_c[INTRA_C_DC_128]     = intra_pred_dc_128;
     h->mv[7]                            = un_mv;
     h->mv[19]                           = un_mv;

     return 0;
 }
 

 av_cold int ff_cavs_end(AVCodecContext *avctx)
 {

     AVSContext *h = avctx->priv_data;

     av_frame_free(&h->cur.f);
     av_frame_free(&h->DPB[0].f);
     av_frame_free(&h->DPB[1].f);

     av_freep(&h->top_qp);
     av_freep(&h->top_mv[0]);
     av_freep(&h->top_mv[1]);
     av_freep(&h->top_pred_Y);
     av_freep(&h->top_border_y);
     av_freep(&h->top_border_u);
     av_freep(&h->top_border_v);
     av_freep(&h->col_mv);
     av_freep(&h->col_type_base);
     av_freep(&h->block);

     av_freep(&h->edge_emu_buffer);

     return 0;
 }