text: /*
   * Error resilience / concealment
   *
   * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
   *
   * 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
   * Error resilience / concealment.
   */
  
  #include <limits.h>
  
  #include "libavutil/internal.h"
  #include "avcodec.h"
  #include "error_resilience.h"
  #include "me_cmp.h"
  #include "mpegutils.h"
  #include "mpegvideo.h"
  #include "rectangle.h"
  #include "thread.h"
  #include "version.h"
  
  /**
   * @param stride the number of MVs to get to the next row
   * @param mv_step the number of MVs per row or column in a macroblock
   */
  static void set_mv_strides(ERContext *s, ptrdiff_t *mv_step, ptrdiff_t *stride)
  {
      if (s->avctx->codec_id == AV_CODEC_ID_H264) {
          av_assert0(s->quarter_sample);
          *mv_step = 4;
          *stride  = s->mb_width * 4;
      } else {
          *mv_step = 2;
          *stride  = s->b8_stride;
      }
  }
  
  /**
   * Replace the current MB with a flat dc-only version.
   */
  static void put_dc(ERContext *s, uint8_t *dest_y, uint8_t *dest_cb,
                     uint8_t *dest_cr, int mb_x, int mb_y)
  {
      int *linesize = s->cur_pic.f->linesize;
      int dc, dcu, dcv, y, i;
      for (i = 0; i < 4; i++) {
          dc = s->dc_val[0][mb_x * 2 + (i &  1) + (mb_y * 2 + (i >> 1)) * s->b8_stride];
          if (dc < 0)
              dc = 0;
          else if (dc > 2040)
              dc = 2040;
          for (y = 0; y < 8; y++) {
              int x;
              for (x = 0; x < 8; x++)
                  dest_y[x + (i &  1) * 8 + (y + (i >> 1) * 8) * linesize[0]] = dc / 8;
          }
      }
      dcu = s->dc_val[1][mb_x + mb_y * s->mb_stride];
      dcv = s->dc_val[2][mb_x + mb_y * s->mb_stride];
      if (dcu < 0)
          dcu = 0;
      else if (dcu > 2040)
          dcu = 2040;
      if (dcv < 0)
          dcv = 0;
      else if (dcv > 2040)
          dcv = 2040;
  
      if (dest_cr)
      for (y = 0; y < 8; y++) {
          int x;
          for (x = 0; x < 8; x++) {
              dest_cb[x + y * linesize[1]] = dcu / 8;
              dest_cr[x + y * linesize[2]] = dcv / 8;
          }
      }
  }
  
  static void filter181(int16_t *data, int width, int height, ptrdiff_t stride)
  {
      int x, y;
  
      /* horizontal filter */
      for (y = 1; y < height - 1; y++) {
          int prev_dc = data[0 + y * stride];
  
          for (x = 1; x < width - 1; x++) {
              int dc;
              dc = -prev_dc +
                   data[x     + y * stride] * 8 -
                   data[x + 1 + y * stride];
              dc = (av_clip(dc, INT_MIN/10923, INT_MAX/10923 - 32768) * 10923 + 32768) >> 16;
              prev_dc = data[x + y * stride];
              data[x + y * stride] = dc;
          }
      }
  
      /* vertical filter */
      for (x = 1; x < width - 1; x++) {
          int prev_dc = data[x];
  
          for (y = 1; y < height - 1; y++) {
              int dc;
  
              dc = -prev_dc +
                   data[x +  y      * stride] * 8 -
                   data[x + (y + 1) * stride];
              dc = (av_clip(dc, INT_MIN/10923, INT_MAX/10923 - 32768) * 10923 + 32768) >> 16;
              prev_dc = data[x + y * stride];
              data[x + y * stride] = dc;
          }
      }
  }
  
  /**
   * guess the dc of blocks which do not have an undamaged dc
   * @param w     width in 8 pixel blocks
   * @param h     height in 8 pixel blocks
   */
  static void guess_dc(ERContext *s, int16_t *dc, int w,
                       int h, ptrdiff_t stride, int is_luma)
  {
      int b_x, b_y;
      int16_t  (*col )[4] = av_malloc_array(stride, h*sizeof( int16_t)*4);
      uint32_t (*dist)[4] = av_malloc_array(stride, h*sizeof(uint32_t)*4);
  
      if(!col || !dist) {
          av_log(s->avctx, AV_LOG_ERROR, "guess_dc() is out of memory\n");
          goto fail;
      }
  
      for(b_y=0; b_y<h; b_y++){
          int color= 1024;
          int distance= -1;
          for(b_x=0; b_x<w; b_x++){
              int mb_index_j= (b_x>>is_luma) + (b_y>>is_luma)*s->mb_stride;
              int error_j= s->error_status_table[mb_index_j];
              int intra_j = IS_INTRA(s->cur_pic.mb_type[mb_index_j]);
              if(intra_j==0 || !(error_j&ER_DC_ERROR)){
                  color= dc[b_x + b_y*stride];
                  distance= b_x;
              }
              col [b_x + b_y*stride][1]= color;
              dist[b_x + b_y*stride][1]= distance >= 0 ? b_x-distance : 9999;
          }
          color= 1024;
          distance= -1;
          for(b_x=w-1; b_x>=0; b_x--){
              int mb_index_j= (b_x>>is_luma) + (b_y>>is_luma)*s->mb_stride;
              int error_j= s->error_status_table[mb_index_j];
              int intra_j = IS_INTRA(s->cur_pic.mb_type[mb_index_j]);
              if(intra_j==0 || !(error_j&ER_DC_ERROR)){
                  color= dc[b_x + b_y*stride];
                  distance= b_x;
              }
              col [b_x + b_y*stride][0]= color;
              dist[b_x + b_y*stride][0]= distance >= 0 ? distance-b_x : 9999;
          }
      }
      for(b_x=0; b_x<w; b_x++){
          int color= 1024;
          int distance= -1;
          for(b_y=0; b_y<h; b_y++){
              int mb_index_j= (b_x>>is_luma) + (b_y>>is_luma)*s->mb_stride;
              int error_j= s->error_status_table[mb_index_j];
              int intra_j = IS_INTRA(s->cur_pic.mb_type[mb_index_j]);
              if(intra_j==0 || !(error_j&ER_DC_ERROR)){
                  color= dc[b_x + b_y*stride];
                  distance= b_y;
              }
              col [b_x + b_y*stride][3]= color;
              dist[b_x + b_y*stride][3]= distance >= 0 ? b_y-distance : 9999;
          }
          color= 1024;
          distance= -1;
          for(b_y=h-1; b_y>=0; b_y--){
              int mb_index_j= (b_x>>is_luma) + (b_y>>is_luma)*s->mb_stride;
              int error_j= s->error_status_table[mb_index_j];
              int intra_j = IS_INTRA(s->cur_pic.mb_type[mb_index_j]);
              if(intra_j==0 || !(error_j&ER_DC_ERROR)){
                  color= dc[b_x + b_y*stride];
                  distance= b_y;
              }
              col [b_x + b_y*stride][2]= color;
              dist[b_x + b_y*stride][2]= distance >= 0 ? distance-b_y : 9999;
          }
      }
  
      for (b_y = 0; b_y < h; b_y++) {
          for (b_x = 0; b_x < w; b_x++) {
              int mb_index, error, j;
              int64_t guess, weight_sum;
              mb_index = (b_x >> is_luma) + (b_y >> is_luma) * s->mb_stride;
              error    = s->error_status_table[mb_index];
  
              if (IS_INTER(s->cur_pic.mb_type[mb_index]))
                  continue; // inter
              if (!(error & ER_DC_ERROR))
                  continue; // dc-ok
  
              weight_sum = 0;
              guess      = 0;
              for (j = 0; j < 4; j++) {
                  int64_t weight  = 256 * 256 * 256 * 16 / FFMAX(dist[b_x + b_y*stride][j], 1);
                  guess          += weight*(int64_t)col[b_x + b_y*stride][j];
                  weight_sum     += weight;
              }
              guess = (guess + weight_sum / 2) / weight_sum;
              dc[b_x + b_y * stride] = guess;
          }
      }
  
  fail:
      av_freep(&col);
      av_freep(&dist);
  }
  
  /**
   * simple horizontal deblocking filter used for error resilience
   * @param w     width in 8 pixel blocks
   * @param h     height in 8 pixel blocks
   */
  static void h_block_filter(ERContext *s, uint8_t *dst, int w,
                             int h, ptrdiff_t stride, int is_luma)
  {
      int b_x, b_y;
      ptrdiff_t mvx_stride, mvy_stride;
      const uint8_t *cm = ff_crop_tab + MAX_NEG_CROP;
      set_mv_strides(s, &mvx_stride, &mvy_stride);
      mvx_stride >>= is_luma;
      mvy_stride *= mvx_stride;
  
      for (b_y = 0; b_y < h; b_y++) {
          for (b_x = 0; b_x < w - 1; b_x++) {
              int y;
              int left_status  = s->error_status_table[( b_x      >> is_luma) + (b_y >> is_luma) * s->mb_stride];
              int right_status = s->error_status_table[((b_x + 1) >> is_luma) + (b_y >> is_luma) * s->mb_stride];
              int left_intra   = IS_INTRA(s->cur_pic.mb_type[( b_x      >> is_luma) + (b_y >> is_luma) * s->mb_stride]);
              int right_intra  = IS_INTRA(s->cur_pic.mb_type[((b_x + 1) >> is_luma) + (b_y >> is_luma) * s->mb_stride]);
              int left_damage  = left_status & ER_MB_ERROR;
              int right_damage = right_status & ER_MB_ERROR;
              int offset       = b_x * 8 + b_y * stride * 8;
              int16_t *left_mv  = s->cur_pic.motion_val[0][mvy_stride * b_y + mvx_stride *  b_x];
              int16_t *right_mv = s->cur_pic.motion_val[0][mvy_stride * b_y + mvx_stride * (b_x + 1)];
              if (!(left_damage || right_damage))
                  continue; // both undamaged
              if ((!left_intra) && (!right_intra) &&
                  FFABS(left_mv[0] - right_mv[0]) +
                  FFABS(left_mv[1] + right_mv[1]) < 2)
                  continue;
  
              for (y = 0; y < 8; y++) {
                  int a, b, c, d;
  
                  a = dst[offset + 7 + y * stride] - dst[offset + 6 + y * stride];
                  b = dst[offset + 8 + y * stride] - dst[offset + 7 + y * stride];
                  c = dst[offset + 9 + y * stride] - dst[offset + 8 + y * stride];
  
                  d = FFABS(b) - ((FFABS(a) + FFABS(c) + 1) >> 1);
                  d = FFMAX(d, 0);
                  if (b < 0)
                      d = -d;
  
                  if (d == 0)
                      continue;
  
                  if (!(left_damage && right_damage))
                      d = d * 16 / 9;
  
                  if (left_damage) {
                      dst[offset + 7 + y * stride] = cm[dst[offset + 7 + y * stride] + ((d * 7) >> 4)];
                      dst[offset + 6 + y * stride] = cm[dst[offset + 6 + y * stride] + ((d * 5) >> 4)];
                      dst[offset + 5 + y * stride] = cm[dst[offset + 5 + y * stride] + ((d * 3) >> 4)];
                      dst[offset + 4 + y * stride] = cm[dst[offset + 4 + y * stride] + ((d * 1) >> 4)];
                  }
                  if (right_damage) {
                      dst[offset + 8 + y * stride] = cm[dst[offset +  8 + y * stride] - ((d * 7) >> 4)];
                      dst[offset + 9 + y * stride] = cm[dst[offset +  9 + y * stride] - ((d * 5) >> 4)];
                      dst[offset + 10+ y * stride] = cm[dst[offset + 10 + y * stride] - ((d * 3) >> 4)];
                      dst[offset + 11+ y * stride] = cm[dst[offset + 11 + y * stride] - ((d * 1) >> 4)];
                  }
              }
          }
      }
  }
  
  /**
   * simple vertical deblocking filter used for error resilience
   * @param w     width in 8 pixel blocks
   * @param h     height in 8 pixel blocks
   */
  static void v_block_filter(ERContext *s, uint8_t *dst, int w, int h,
                             ptrdiff_t stride, int is_luma)
  {
      int b_x, b_y;
      ptrdiff_t mvx_stride, mvy_stride;
      const uint8_t *cm = ff_crop_tab + MAX_NEG_CROP;
      set_mv_strides(s, &mvx_stride, &mvy_stride);
      mvx_stride >>= is_luma;
      mvy_stride *= mvx_stride;
  
      for (b_y = 0; b_y < h - 1; b_y++) {
          for (b_x = 0; b_x < w; b_x++) {
              int x;
              int top_status    = s->error_status_table[(b_x >> is_luma) +  (b_y      >> is_luma) * s->mb_stride];
              int bottom_status = s->error_status_table[(b_x >> is_luma) + ((b_y + 1) >> is_luma) * s->mb_stride];
              int top_intra     = IS_INTRA(s->cur_pic.mb_type[(b_x >> is_luma) + ( b_y      >> is_luma) * s->mb_stride]);
              int bottom_intra  = IS_INTRA(s->cur_pic.mb_type[(b_x >> is_luma) + ((b_y + 1) >> is_luma) * s->mb_stride]);
              int top_damage    = top_status & ER_MB_ERROR;
              int bottom_damage = bottom_status & ER_MB_ERROR;
              int offset        = b_x * 8 + b_y * stride * 8;
  
              int16_t *top_mv    = s->cur_pic.motion_val[0][mvy_stride *  b_y      + mvx_stride * b_x];
              int16_t *bottom_mv = s->cur_pic.motion_val[0][mvy_stride * (b_y + 1) + mvx_stride * b_x];
  
              if (!(top_damage || bottom_damage))
                  continue; // both undamaged
  
              if ((!top_intra) && (!bottom_intra) &&
                  FFABS(top_mv[0] - bottom_mv[0]) +
                  FFABS(top_mv[1] + bottom_mv[1]) < 2)
                  continue;
  
              for (x = 0; x < 8; x++) {
                  int a, b, c, d;
  
                  a = dst[offset + x + 7 * stride] - dst[offset + x + 6 * stride];
                  b = dst[offset + x + 8 * stride] - dst[offset + x + 7 * stride];
                  c = dst[offset + x + 9 * stride] - dst[offset + x + 8 * stride];
  
                  d = FFABS(b) - ((FFABS(a) + FFABS(c) + 1) >> 1);
                  d = FFMAX(d, 0);
                  if (b < 0)
                      d = -d;
  
                  if (d == 0)
                      continue;
  
                  if (!(top_damage && bottom_damage))
                      d = d * 16 / 9;
  
                  if (top_damage) {
                      dst[offset + x +  7 * stride] = cm[dst[offset + x +  7 * stride] + ((d * 7) >> 4)];
                      dst[offset + x +  6 * stride] = cm[dst[offset + x +  6 * stride] + ((d * 5) >> 4)];
                      dst[offset + x +  5 * stride] = cm[dst[offset + x +  5 * stride] + ((d * 3) >> 4)];
                      dst[offset + x +  4 * stride] = cm[dst[offset + x +  4 * stride] + ((d * 1) >> 4)];
                  }
                  if (bottom_damage) {
                      dst[offset + x +  8 * stride] = cm[dst[offset + x +  8 * stride] - ((d * 7) >> 4)];
                      dst[offset + x +  9 * stride] = cm[dst[offset + x +  9 * stride] - ((d * 5) >> 4)];
                      dst[offset + x + 10 * stride] = cm[dst[offset + x + 10 * stride] - ((d * 3) >> 4)];
                      dst[offset + x + 11 * stride] = cm[dst[offset + x + 11 * stride] - ((d * 1) >> 4)];
                  }
              }
          }
      }
  }
  
  #define MV_FROZEN    8
  #define MV_CHANGED   4
  #define MV_UNCHANGED 2
  #define MV_LISTED    1
  static av_always_inline void add_blocklist(int (*blocklist)[2], int *blocklist_length, uint8_t *fixed, int mb_x, int mb_y, int mb_xy)
  {
      if (fixed[mb_xy])
          return;
      fixed[mb_xy] = MV_LISTED;
      blocklist[ *blocklist_length   ][0] = mb_x;
      blocklist[(*blocklist_length)++][1] = mb_y;
  }
  
  static void guess_mv(ERContext *s)
  {
      int (*blocklist)[2], (*next_blocklist)[2];
      uint8_t *fixed;
      const ptrdiff_t mb_stride = s->mb_stride;
      const int mb_width  = s->mb_width;
      int mb_height = s->mb_height;
      int i, depth, num_avail;
      int mb_x, mb_y;
      ptrdiff_t mot_step, mot_stride;
      int blocklist_length, next_blocklist_length;
  
      if (s->last_pic.f && s->last_pic.f->data[0])
          mb_height = FFMIN(mb_height, (s->last_pic.f->height+15)>>4);
      if (s->next_pic.f && s->next_pic.f->data[0])
          mb_height = FFMIN(mb_height, (s->next_pic.f->height+15)>>4);
  
      blocklist      = (int (*)[2])s->er_temp_buffer;
      next_blocklist = blocklist + s->mb_stride * s->mb_height;
      fixed          = (uint8_t *)(next_blocklist + s->mb_stride * s->mb_height);
  
      set_mv_strides(s, &mot_step, &mot_stride);
  
      num_avail = 0;
      if (s->last_pic.motion_val[0])
          ff_thread_await_progress(s->last_pic.tf, mb_height-1, 0);
      for (i = 0; i < mb_width * mb_height; i++) {
          const int mb_xy = s->mb_index2xy[i];
          int f = 0;
          int error = s->error_status_table[mb_xy];
  
          if (IS_INTRA(s->cur_pic.mb_type[mb_xy]))
              f = MV_FROZEN; // intra // FIXME check
          if (!(error & ER_MV_ERROR))
              f = MV_FROZEN; // inter with undamaged MV
  
          fixed[mb_xy] = f;
          if (f == MV_FROZEN)
              num_avail++;
          else if(s->last_pic.f->data[0] && s->last_pic.motion_val[0]){
              const int mb_y= mb_xy / s->mb_stride;
              const int mb_x= mb_xy % s->mb_stride;
              const int mot_index= (mb_x + mb_y*mot_stride) * mot_step;
              s->cur_pic.motion_val[0][mot_index][0]= s->last_pic.motion_val[0][mot_index][0];
              s->cur_pic.motion_val[0][mot_index][1]= s->last_pic.motion_val[0][mot_index][1];
              s->cur_pic.ref_index[0][4*mb_xy]      = s->last_pic.ref_index[0][4*mb_xy];
          }
      }
  
      if ((!(s->avctx->error_concealment&FF_EC_GUESS_MVS)) ||
          num_avail <= FFMAX(mb_width, mb_height) / 2) {
          for (mb_y = 0; mb_y < mb_height; mb_y++) {
              for (mb_x = 0; mb_x < s->mb_width; mb_x++) {
                  const int mb_xy = mb_x + mb_y * s->mb_stride;
                  int mv_dir = (s->last_pic.f && s->last_pic.f->data[0]) ? MV_DIR_FORWARD : MV_DIR_BACKWARD;
  
                  if (IS_INTRA(s->cur_pic.mb_type[mb_xy]))
                      continue;
                  if (!(s->error_status_table[mb_xy] & ER_MV_ERROR))
                      continue;
  
                  s->mv[0][0][0] = 0;
                  s->mv[0][0][1] = 0;
                  s->decode_mb(s->opaque, 0, mv_dir, MV_TYPE_16X16, &s->mv,
                               mb_x, mb_y, 0, 0);
              }
          }
          return;
      }
  
      blocklist_length = 0;
      for (mb_y = 0; mb_y < mb_height; mb_y++) {
          for (mb_x = 0; mb_x < mb_width; mb_x++) {
              const int mb_xy = mb_x + mb_y * mb_stride;
              if (fixed[mb_xy] == MV_FROZEN) {
                  if (mb_x)               add_blocklist(blocklist, &blocklist_length, fixed, mb_x - 1, mb_y, mb_xy - 1);
                  if (mb_y)               add_blocklist(blocklist, &blocklist_length, fixed, mb_x, mb_y - 1, mb_xy - mb_stride);
                  if (mb_x+1 < mb_width)  add_blocklist(blocklist, &blocklist_length, fixed, mb_x + 1, mb_y, mb_xy + 1);
                  if (mb_y+1 < mb_height) add_blocklist(blocklist, &blocklist_length, fixed, mb_x, mb_y + 1, mb_xy + mb_stride);
              }
          }
      }
  
      for (depth = 0; ; depth++) {
          int changed, pass, none_left;
          int blocklist_index;
  
          none_left = 1;
          changed   = 1;
          for (pass = 0; (changed || pass < 2) && pass < 10; pass++) {
              int score_sum = 0;
  
              changed = 0;
              for (blocklist_index = 0; blocklist_index < blocklist_length; blocklist_index++) {
                  const int mb_x = blocklist[blocklist_index][0];
                  const int mb_y = blocklist[blocklist_index][1];
                  const int mb_xy = mb_x + mb_y * mb_stride;
                  int mv_predictor[8][2];
                  int ref[8];
                  int pred_count;
                  int j;
                  int best_score;
                  int best_pred;
                  int mot_index;
                  int prev_x, prev_y, prev_ref;
  
                  if ((mb_x ^ mb_y ^ pass) & 1)
                      continue;
                  av_assert2(fixed[mb_xy] != MV_FROZEN);
  
  
                  av_assert1(!IS_INTRA(s->cur_pic.mb_type[mb_xy]));
                  av_assert1(s->last_pic.f && s->last_pic.f->data[0]);
  
                  j = 0;
                  if (mb_x > 0)
                      j |= fixed[mb_xy - 1];
                  if (mb_x + 1 < mb_width)
                      j |= fixed[mb_xy + 1];
                  if (mb_y > 0)
                      j |= fixed[mb_xy - mb_stride];
                  if (mb_y + 1 < mb_height)
                      j |= fixed[mb_xy + mb_stride];
  
                  av_assert2(j & MV_FROZEN);
  
                  if (!(j & MV_CHANGED) && pass > 1)
                      continue;
  
                  none_left = 0;
                  pred_count = 0;
                  mot_index  = (mb_x + mb_y * mot_stride) * mot_step;
  
                  if (mb_x > 0 && fixed[mb_xy - 1] > 1) {
                      mv_predictor[pred_count][0] =
                          s->cur_pic.motion_val[0][mot_index - mot_step][0];
                      mv_predictor[pred_count][1] =
                          s->cur_pic.motion_val[0][mot_index - mot_step][1];
                      ref[pred_count] =
                          s->cur_pic.ref_index[0][4 * (mb_xy - 1)];
                      pred_count++;
                  }
                  if (mb_x + 1 < mb_width && fixed[mb_xy + 1] > 1) {
                      mv_predictor[pred_count][0] =
                          s->cur_pic.motion_val[0][mot_index + mot_step][0];
                      mv_predictor[pred_count][1] =
                          s->cur_pic.motion_val[0][mot_index + mot_step][1];
                      ref[pred_count] =
                          s->cur_pic.ref_index[0][4 * (mb_xy + 1)];
                      pred_count++;
                  }
                  if (mb_y > 0 && fixed[mb_xy - mb_stride] > 1) {
                      mv_predictor[pred_count][0] =
                          s->cur_pic.motion_val[0][mot_index - mot_stride * mot_step][0];
                      mv_predictor[pred_count][1] =
                          s->cur_pic.motion_val[0][mot_index - mot_stride * mot_step][1];
                      ref[pred_count] =
                          s->cur_pic.ref_index[0][4 * (mb_xy - s->mb_stride)];
                      pred_count++;
                  }
                  if (mb_y + 1<mb_height && fixed[mb_xy + mb_stride] > 1) {
                      mv_predictor[pred_count][0] =
                          s->cur_pic.motion_val[0][mot_index + mot_stride * mot_step][0];
                      mv_predictor[pred_count][1] =
                          s->cur_pic.motion_val[0][mot_index + mot_stride * mot_step][1];
                      ref[pred_count] =
                          s->cur_pic.ref_index[0][4 * (mb_xy + s->mb_stride)];
                      pred_count++;
                  }
                  if (pred_count == 0)
                      continue;
  
                  if (pred_count > 1) {
                      int sum_x = 0, sum_y = 0, sum_r = 0;
                      int max_x, max_y, min_x, min_y, max_r, min_r;
  
                      for (j = 0; j < pred_count; j++) {
                          sum_x += mv_predictor[j][0];
                          sum_y += mv_predictor[j][1];
                          sum_r += ref[j];
                          if (j && ref[j] != ref[j - 1])
                              goto skip_mean_and_median;
                      }
  
                      /* mean */
                      mv_predictor[pred_count][0] = sum_x / j;
                      mv_predictor[pred_count][1] = sum_y / j;
                               ref[pred_count]    = sum_r / j;
  
                      /* median */
                      if (pred_count >= 3) {
                          min_y = min_x = min_r =  99999;
                          max_y = max_x = max_r = -99999;
                      } else {
                          min_x = min_y = max_x = max_y = min_r = max_r = 0;
                      }
                      for (j = 0; j < pred_count; j++) {
                          max_x = FFMAX(max_x, mv_predictor[j][0]);
                          max_y = FFMAX(max_y, mv_predictor[j][1]);
                          max_r = FFMAX(max_r, ref[j]);
                          min_x = FFMIN(min_x, mv_predictor[j][0]);
                          min_y = FFMIN(min_y, mv_predictor[j][1]);
                          min_r = FFMIN(min_r, ref[j]);
                      }
                      mv_predictor[pred_count + 1][0] = sum_x - max_x - min_x;
                      mv_predictor[pred_count + 1][1] = sum_y - max_y - min_y;
                               ref[pred_count + 1]    = sum_r - max_r - min_r;
  
                      if (pred_count == 4) {
                          mv_predictor[pred_count + 1][0] /= 2;
                          mv_predictor[pred_count + 1][1] /= 2;
                                   ref[pred_count + 1]    /= 2;
                      }
                      pred_count += 2;
                  }
  
  skip_mean_and_median:
                  /* zero MV */
                  mv_predictor[pred_count][0] =
                  mv_predictor[pred_count][1] =
                           ref[pred_count]    = 0;
                  pred_count++;
  
                  prev_x   = s->cur_pic.motion_val[0][mot_index][0];
                  prev_y   = s->cur_pic.motion_val[0][mot_index][1];
                  prev_ref = s->cur_pic.ref_index[0][4 * mb_xy];
  
                  /* last MV */
                  mv_predictor[pred_count][0] = prev_x;
                  mv_predictor[pred_count][1] = prev_y;
                           ref[pred_count]    = prev_ref;
                  pred_count++;
  
                  best_pred = 0;
                  best_score = 256 * 256 * 256 * 64;
                  for (j = 0; j < pred_count; j++) {
                      int *linesize = s->cur_pic.f->linesize;
                      int score = 0;
                      uint8_t *src = s->cur_pic.f->data[0] +
                                     mb_x * 16 + mb_y * 16 * linesize[0];
  
                      s->cur_pic.motion_val[0][mot_index][0] =
                          s->mv[0][0][0] = mv_predictor[j][0];
                      s->cur_pic.motion_val[0][mot_index][1] =
                          s->mv[0][0][1] = mv_predictor[j][1];
  
                      // predictor intra or otherwise not available
                      if (ref[j] < 0)
                          continue;
  
                      s->decode_mb(s->opaque, ref[j], MV_DIR_FORWARD,
                                   MV_TYPE_16X16, &s->mv, mb_x, mb_y, 0, 0);
  
                      if (mb_x > 0 && fixed[mb_xy - 1] > 1) {
                          int k;
                          for (k = 0; k < 16; k++)
                              score += FFABS(src[k * linesize[0] - 1] -
                                             src[k * linesize[0]]);
                      }
                      if (mb_x + 1 < mb_width && fixed[mb_xy + 1] > 1) {
                          int k;
                          for (k = 0; k < 16; k++)
                              score += FFABS(src[k * linesize[0] + 15] -
                                             src[k * linesize[0] + 16]);
                      }
                      if (mb_y > 0 && fixed[mb_xy - mb_stride] > 1) {
                          int k;
                          for (k = 0; k < 16; k++)
                              score += FFABS(src[k - linesize[0]] - src[k]);
                      }
                      if (mb_y + 1 < mb_height && fixed[mb_xy + mb_stride] > 1) {
                          int k;
                          for (k = 0; k < 16; k++)
                              score += FFABS(src[k + linesize[0] * 15] -
                                             src[k + linesize[0] * 16]);
                      }
  
                      if (score <= best_score) { // <= will favor the last MV
                          best_score = score;
                          best_pred  = j;
                      }
                  }
                  score_sum += best_score;
                  s->mv[0][0][0] = mv_predictor[best_pred][0];
                  s->mv[0][0][1] = mv_predictor[best_pred][1];
  
                  for (i = 0; i < mot_step; i++)
                      for (j = 0; j < mot_step; j++) {
                          s->cur_pic.motion_val[0][mot_index + i + j * mot_stride][0] = s->mv[0][0][0];
                          s->cur_pic.motion_val[0][mot_index + i + j * mot_stride][1] = s->mv[0][0][1];
                      }
  
                  s->decode_mb(s->opaque, ref[best_pred], MV_DIR_FORWARD,
                               MV_TYPE_16X16, &s->mv, mb_x, mb_y, 0, 0);
  
  
                  if (s->mv[0][0][0] != prev_x || s->mv[0][0][1] != prev_y) {
                      fixed[mb_xy] = MV_CHANGED;
                      changed++;
                  } else
                      fixed[mb_xy] = MV_UNCHANGED;
              }
          }
  
          if (none_left)
              return;
  
          next_blocklist_length = 0;
  
          for (blocklist_index = 0; blocklist_index < blocklist_length; blocklist_index++) {
              const int mb_x = blocklist[blocklist_index][0];
              const int mb_y = blocklist[blocklist_index][1];
              const int mb_xy = mb_x + mb_y * mb_stride;
  
              if (fixed[mb_xy] & (MV_CHANGED|MV_UNCHANGED|MV_FROZEN)) {
                  fixed[mb_xy] = MV_FROZEN;
                  if (mb_x > 0)
                      add_blocklist(next_blocklist, &next_blocklist_length, fixed, mb_x - 1, mb_y, mb_xy - 1);
                  if (mb_y > 0)
                      add_blocklist(next_blocklist, &next_blocklist_length, fixed, mb_x, mb_y - 1, mb_xy - mb_stride);
                  if (mb_x + 1 < mb_width)
                      add_blocklist(next_blocklist, &next_blocklist_length, fixed, mb_x + 1, mb_y, mb_xy + 1);
                  if (mb_y + 1 < mb_height)
                      add_blocklist(next_blocklist, &next_blocklist_length, fixed, mb_x, mb_y + 1, mb_xy + mb_stride);
              }
          }
          av_assert0(next_blocklist_length <= mb_height * mb_width);
          FFSWAP(int , blocklist_length, next_blocklist_length);
          FFSWAP(void*, blocklist, next_blocklist);
      }
  }
  
  static int is_intra_more_likely(ERContext *s)
  {
      int is_intra_likely, i, j, undamaged_count, skip_amount, mb_x, mb_y;
  
      if (!s->last_pic.f || !s->last_pic.f->data[0])
          return 1; // no previous frame available -> use spatial prediction
  
      if (s->avctx->error_concealment & FF_EC_FAVOR_INTER)
          return 0;
  
      undamaged_count = 0;
      for (i = 0; i < s->mb_num; i++) {
          const int mb_xy = s->mb_index2xy[i];
          const int error = s->error_status_table[mb_xy];
          if (!((error & ER_DC_ERROR) && (error & ER_MV_ERROR)))
              undamaged_count++;
      }
  
      if (undamaged_count < 5)
          return 0; // almost all MBs damaged -> use temporal prediction
  
      // prevent dsp.sad() check, that requires access to the image
      if (CONFIG_XVMC    &&
          s->avctx->hwaccel && s->avctx->hwaccel->decode_mb &&
          s->cur_pic.f->pict_type == AV_PICTURE_TYPE_I)
          return 1;
  
      skip_amount     = FFMAX(undamaged_count / 50, 1); // check only up to 50 MBs
      is_intra_likely = 0;
  
      j = 0;
      for (mb_y = 0; mb_y < s->mb_height - 1; mb_y++) {
          for (mb_x = 0; mb_x < s->mb_width; mb_x++) {
              int error;
              const int mb_xy = mb_x + mb_y * s->mb_stride;
  
              error = s->error_status_table[mb_xy];
              if ((error & ER_DC_ERROR) && (error & ER_MV_ERROR))
                  continue; // skip damaged
  
              j++;
              // skip a few to speed things up
              if ((j % skip_amount) != 0)
                  continue;
  
              if (s->cur_pic.f->pict_type == AV_PICTURE_TYPE_I) {
                  int *linesize = s->cur_pic.f->linesize;
                  uint8_t *mb_ptr      = s->cur_pic.f->data[0] +
                                         mb_x * 16 + mb_y * 16 * linesize[0];
                  uint8_t *last_mb_ptr = s->last_pic.f->data[0] +
                                         mb_x * 16 + mb_y * 16 * linesize[0];
  
                  if (s->avctx->codec_id == AV_CODEC_ID_H264) {
                      // FIXME
                  } else {
                      ff_thread_await_progress(s->last_pic.tf, mb_y, 0);
                  }
                  is_intra_likely += s->mecc.sad[0](NULL, last_mb_ptr, mb_ptr,
                                                    linesize[0], 16);
                  // FIXME need await_progress() here
                  is_intra_likely -= s->mecc.sad[0](NULL, last_mb_ptr,
                                                    last_mb_ptr + linesize[0] * 16,
                                                    linesize[0], 16);
              } else {
                  if (IS_INTRA(s->cur_pic.mb_type[mb_xy]))
                     is_intra_likely++;
                  else
                     is_intra_likely--;
              }
          }
      }
  //      av_log(NULL, AV_LOG_ERROR, "is_intra_likely: %d type:%d\n", is_intra_likely, s->pict_type);
      return is_intra_likely > 0;
  }
  
  void ff_er_frame_start(ERContext *s)
  {
      if (!s->avctx->error_concealment)
          return;
  
      if (!s->mecc_inited) {
          ff_me_cmp_init(&s->mecc, s->avctx);
          s->mecc_inited = 1;
      }
  
      memset(s->error_status_table, ER_MB_ERROR | VP_START | ER_MB_END,
             s->mb_stride * s->mb_height * sizeof(uint8_t));
      atomic_init(&s->error_count, 3 * s->mb_num);
      s->error_occurred = 0;
  }
  
  static int er_supported(ERContext *s)
  {
      if(s->avctx->hwaccel && s->avctx->hwaccel->decode_slice           ||
         !s->cur_pic.f                                                  ||
         s->cur_pic.field_picture
      )
          return 0;
      return 1;
  }
  
  /**
   * Add a slice.
   * @param endx   x component of the last macroblock, can be -1
   *               for the last of the previous line
   * @param status the status at the end (ER_MV_END, ER_AC_ERROR, ...), it is
   *               assumed that no earlier end or error of the same type occurred
   */
  void ff_er_add_slice(ERContext *s, int startx, int starty,
                       int endx, int endy, int status)
  {
      const int start_i  = av_clip(startx + starty * s->mb_width, 0, s->mb_num - 1);
      const int end_i    = av_clip(endx   + endy   * s->mb_width, 0, s->mb_num);
      const int start_xy = s->mb_index2xy[start_i];
      const int end_xy   = s->mb_index2xy[end_i];
      int mask           = -1;
  
      if (s->avctx->hwaccel && s->avctx->hwaccel->decode_slice)
          return;
  
      if (start_i > end_i || start_xy > end_xy) {
          av_log(s->avctx, AV_LOG_ERROR,
                 "internal error, slice end before start\n");
          return;
      }
  
      if (!s->avctx->error_concealment)
          return;
  
      mask &= ~VP_START;
      if (status & (ER_AC_ERROR | ER_AC_END)) {
          mask           &= ~(ER_AC_ERROR | ER_AC_END);
          atomic_fetch_add(&s->error_count, start_i - end_i - 1);
      }
      if (status & (ER_DC_ERROR | ER_DC_END)) {
          mask           &= ~(ER_DC_ERROR | ER_DC_END);
          atomic_fetch_add(&s->error_count, start_i - end_i - 1);
      }
      if (status & (ER_MV_ERROR | ER_MV_END)) {
          mask           &= ~(ER_MV_ERROR | ER_MV_END);
          atomic_fetch_add(&s->error_count, start_i - end_i - 1);
      }
  
      if (status & ER_MB_ERROR) {
          s->error_occurred = 1;
          atomic_store(&s->error_count, INT_MAX);
      }
  
      if (mask == ~0x7F) {
          memset(&s->error_status_table[start_xy], 0,
                 (end_xy - start_xy) * sizeof(uint8_t));
      } else {
          int i;
          for (i = start_xy; i < end_xy; i++)
              s->error_status_table[i] &= mask;
      }
  
      if (end_i == s->mb_num)
          atomic_store(&s->error_count, INT_MAX);
      else {
          s->error_status_table[end_xy] &= mask;
          s->error_status_table[end_xy] |= status;
      }
  
      s->error_status_table[start_xy] |= VP_START;
  
      if (start_xy > 0 && !(s->avctx->active_thread_type & FF_THREAD_SLICE) &&
          er_supported(s) && s->avctx->skip_top * s->mb_width < start_i) {
          int prev_status = s->error_status_table[s->mb_index2xy[start_i - 1]];
  
          prev_status &= ~ VP_START;
          if (prev_status != (ER_MV_END | ER_DC_END | ER_AC_END)) {
              s->error_occurred = 1;
              atomic_store(&s->error_count, INT_MAX);
          }
      }
  }
  
  void ff_er_frame_end(ERContext *s)
  {
      int *linesize = NULL;
      int i, mb_x, mb_y, error, error_type, dc_error, mv_error, ac_error;
      int distance;
      int threshold_part[4] = { 100, 100, 100 };
      int threshold = 50;
      int is_intra_likely;
      int size = s->b8_stride * 2 * s->mb_height;
  
      /* We do not support ER of field pictures yet,
       * though it should not crash if enabled. */
      if (!s->avctx->error_concealment || !atomic_load(&s->error_count)  ||
          s->avctx->lowres                                               ||
          !er_supported(s)                                               ||
          atomic_load(&s->error_count) == 3 * s->mb_width *
                            (s->avctx->skip_top + s->avctx->skip_bottom)) {
          return;
      }
      linesize = s->cur_pic.f->linesize;
      for (mb_x = 0; mb_x < s->mb_width; mb_x++) {
          int status = s->error_status_table[mb_x + (s->mb_height - 1) * s->mb_stride];
          if (status != 0x7F)
              break;
      }
  
      if (   mb_x == s->mb_width
          && s->avctx->codec_id == AV_CODEC_ID_MPEG2VIDEO
          && (FFALIGN(s->avctx->height, 16)&16)
          && atomic_load(&s->error_count) == 3 * s->mb_width * (s->avctx->skip_top + s->avctx->skip_bottom + 1)
      ) {
          av_log(s->avctx, AV_LOG_DEBUG, "ignoring last missing slice\n");
          return;
      }
  
      if (s->last_pic.f) {
          if (s->last_pic.f->width  != s->cur_pic.f->width  ||
              s->last_pic.f->height != s->cur_pic.f->height ||
              s->last_pic.f->format != s->cur_pic.f->format) {
              av_log(s->avctx, AV_LOG_WARNING, "Cannot use previous picture in error concealment\n");
              memset(&s->last_pic, 0, sizeof(s->last_pic));
          }
      }
      if (s->next_pic.f) {
          if (s->next_pic.f->width  != s->cur_pic.f->width  ||
              s->next_pic.f->height != s->cur_pic.f->height ||
              s->next_pic.f->format != s->cur_pic.f->format) {
              av_log(s->avctx, AV_LOG_WARNING, "Cannot use next picture in error concealment\n");
              memset(&s->next_pic, 0, sizeof(s->next_pic));
          }
      }
  
      if (!s->cur_pic.motion_val[0] || !s->cur_pic.ref_index[0]) {
          av_log(s->avctx, AV_LOG_ERROR, "Warning MVs not available\n");
  
          for (i = 0; i < 2; i++) {
              s->ref_index_buf[i]  = av_buffer_allocz(s->mb_stride * s->mb_height * 4 * sizeof(uint8_t));
              s->motion_val_buf[i] = av_buffer_allocz((size + 4) * 2 * sizeof(uint16_t));
              if (!s->ref_index_buf[i] || !s->motion_val_buf[i])
                  break;
              s->cur_pic.ref_index[i]  = s->ref_index_buf[i]->data;
              s->cur_pic.motion_val[i] = (int16_t (*)[2])s->motion_val_buf[i]->data + 4;
          }
          if (i < 2) {
              for (i = 0; i < 2; i++) {
                  av_buffer_unref(&s->ref_index_buf[i]);
                  av_buffer_unref(&s->motion_val_buf[i]);
                  s->cur_pic.ref_index[i]  = NULL;
                  s->cur_pic.motion_val[i] = NULL;
              }
              return;
          }
      }
  
      if (s->avctx->debug & FF_DEBUG_ER) {
          for (mb_y = 0; mb_y < s->mb_height; mb_y++) {
              for (mb_x = 0; mb_x < s->mb_width; mb_x++) {
                  int status = s->error_status_table[mb_x + mb_y * s->mb_stride];
  
                  av_log(s->avctx, AV_LOG_DEBUG, "%2X ", status);
              }
              av_log(s->avctx, AV_LOG_DEBUG, "\n");
          }
      }
  
  #if 1
      /* handle overlapping slices */
      for (error_type = 1; error_type <= 3; error_type++) {
          int end_ok = 0;
  
          for (i = s->mb_num - 1; i >= 0; i--) {
              const int mb_xy = s->mb_index2xy[i];
              int error       = s->error_status_table[mb_xy];
  
              if (error & (1 << error_type))
                  end_ok = 1;
              if (error & (8 << error_type))
                  end_ok = 1;
  
              if (!end_ok)
                  s->error_status_table[mb_xy] |= 1 << error_type;
  
              if (error & VP_START)
                  end_ok = 0;
          }
      }
  #endif
  #if 1
      /* handle slices with partitions of different length */
      if (s->partitioned_frame) {
          int end_ok = 0;
  
          for (i = s->mb_num - 1; i >= 0; i--) {
              const int mb_xy = s->mb_index2xy[i];
              int error       = s->error_status_table[mb_xy];
  
              if (error & ER_AC_END)
                  end_ok = 0;
              if ((error & ER_MV_END) ||
                  (error & ER_DC_END) ||
                  (error & ER_AC_ERROR))
                  end_ok = 1;
  
              if (!end_ok)
                  s->error_status_table[mb_xy]|= ER_AC_ERROR;
  
              if (error & VP_START)
                  end_ok = 0;
          }
      }
  #endif
      /* handle missing slices */
      if (s->avctx->err_recognition & AV_EF_EXPLODE) {
          int end_ok = 1;
  
          // FIXME + 100 hack
          for (i = s->mb_num - 2; i >= s->mb_width + 100; i--) {
              const int mb_xy = s->mb_index2xy[i];
              int error1 = s->error_status_table[mb_xy];
              int error2 = s->error_status_table[s->mb_index2xy[i + 1]];
  
              if (error1 & VP_START)
                  end_ok = 1;
  
              if (error2 == (VP_START | ER_MB_ERROR | ER_MB_END) &&
                  error1 != (VP_START | ER_MB_ERROR | ER_MB_END) &&
                  ((error1 & ER_AC_END) || (error1 & ER_DC_END) ||
                  (error1 & ER_MV_END))) {
                  // end & uninit
                  end_ok = 0;
              }
  
              if (!end_ok)
                  s->error_status_table[mb_xy] |= ER_MB_ERROR;
          }
      }
  
  #if 1
      /* backward mark errors */
      distance = 9999999;
      for (error_type = 1; error_type <= 3; error_type++) {
          for (i = s->mb_num - 1; i >= 0; i--) {
              const int mb_xy = s->mb_index2xy[i];
              int       error = s->error_status_table[mb_xy];
  
              if (!s->mbskip_table || !s->mbskip_table[mb_xy]) // FIXME partition specific
                  distance++;
              if (error & (1 << error_type))
                  distance = 0;
  
              if (s->partitioned_frame) {
                  if (distance < threshold_part[error_type - 1])
                      s->error_status_table[mb_xy] |= 1 << error_type;
              } else {
                  if (distance < threshold)
                      s->error_status_table[mb_xy] |= 1 << error_type;
              }
  
              if (error & VP_START)
                  distance = 9999999;
          }
      }
  #endif
  
      /* forward mark errors */
      error = 0;
      for (i = 0; i < s->mb_num; i++) {
          const int mb_xy = s->mb_index2xy[i];
          int old_error   = s->error_status_table[mb_xy];
  
          if (old_error & VP_START) {
              error = old_error & ER_MB_ERROR;
          } else {
              error |= old_error & ER_MB_ERROR;
              s->error_status_table[mb_xy] |= error;
          }
      }
  #if 1
      /* handle not partitioned case */
      if (!s->partitioned_frame) {
          for (i = 0; i < s->mb_num; i++) {
              const int mb_xy = s->mb_index2xy[i];
              int error = s->error_status_table[mb_xy];
              if (error & ER_MB_ERROR)
                  error |= ER_MB_ERROR;
              s->error_status_table[mb_xy] = error;
          }
      }
  #endif
  
      dc_error = ac_error = mv_error = 0;
      for (i = 0; i < s->mb_num; i++) {
          const int mb_xy = s->mb_index2xy[i];
          int error = s->error_status_table[mb_xy];
          if (error & ER_DC_ERROR)
              dc_error++;
          if (error & ER_AC_ERROR)
              ac_error++;
          if (error & ER_MV_ERROR)
              mv_error++;
      }
      av_log(s->avctx, AV_LOG_INFO, "concealing %d DC, %d AC, %d MV errors in %c frame\n",
             dc_error, ac_error, mv_error, av_get_picture_type_char(s->cur_pic.f->pict_type));
  
      is_intra_likely = is_intra_more_likely(s);
  
      /* set unknown mb-type to most likely */
      for (i = 0; i < s->mb_num; i++) {
          const int mb_xy = s->mb_index2xy[i];
          int error = s->error_status_table[mb_xy];
          if (!((error & ER_DC_ERROR) && (error & ER_MV_ERROR)))
              continue;
  
          if (is_intra_likely)
              s->cur_pic.mb_type[mb_xy] = MB_TYPE_INTRA4x4;
          else
              s->cur_pic.mb_type[mb_xy] = MB_TYPE_16x16 | MB_TYPE_L0;
      }
  
      // change inter to intra blocks if no reference frames are available
      if (!(s->last_pic.f && s->last_pic.f->data[0]) &&
          !(s->next_pic.f && s->next_pic.f->data[0]))
          for (i = 0; i < s->mb_num; i++) {
              const int mb_xy = s->mb_index2xy[i];
              if (!IS_INTRA(s->cur_pic.mb_type[mb_xy]))
                  s->cur_pic.mb_type[mb_xy] = MB_TYPE_INTRA4x4;
          }
  
      /* handle inter blocks with damaged AC */
      for (mb_y = 0; mb_y < s->mb_height; mb_y++) {
          for (mb_x = 0; mb_x < s->mb_width; mb_x++) {
              const int mb_xy   = mb_x + mb_y * s->mb_stride;
              const int mb_type = s->cur_pic.mb_type[mb_xy];
              const int dir     = !(s->last_pic.f && s->last_pic.f->data[0]);
              const int mv_dir  = dir ? MV_DIR_BACKWARD : MV_DIR_FORWARD;
              int mv_type;
  
              int error = s->error_status_table[mb_xy];
  
              if (IS_INTRA(mb_type))
                  continue; // intra
              if (error & ER_MV_ERROR)
                  continue; // inter with damaged MV
              if (!(error & ER_AC_ERROR))
                  continue; // undamaged inter
  
              if (IS_8X8(mb_type)) {
                  int mb_index = mb_x * 2 + mb_y * 2 * s->b8_stride;
                  int j;
                  mv_type = MV_TYPE_8X8;
                  for (j = 0; j < 4; j++) {
                      s->mv[0][j][0] = s->cur_pic.motion_val[dir][mb_index + (j & 1) + (j >> 1) * s->b8_stride][0];
                      s->mv[0][j][1] = s->cur_pic.motion_val[dir][mb_index + (j & 1) + (j >> 1) * s->b8_stride][1];
                  }
              } else {
                  mv_type     = MV_TYPE_16X16;
                  s->mv[0][0][0] = s->cur_pic.motion_val[dir][mb_x * 2 + mb_y * 2 * s->b8_stride][0];
                  s->mv[0][0][1] = s->cur_pic.motion_val[dir][mb_x * 2 + mb_y * 2 * s->b8_stride][1];
              }
  
              s->decode_mb(s->opaque, 0 /* FIXME H.264 partitioned slices need this set */,
                           mv_dir, mv_type, &s->mv, mb_x, mb_y, 0, 0);
          }
      }
  
      /* guess MVs */
      if (s->cur_pic.f->pict_type == AV_PICTURE_TYPE_B) {
          for (mb_y = 0; mb_y < s->mb_height; mb_y++) {
              for (mb_x = 0; mb_x < s->mb_width; mb_x++) {
                  int       xy      = mb_x * 2 + mb_y * 2 * s->b8_stride;
                  const int mb_xy   = mb_x + mb_y * s->mb_stride;
                  const int mb_type = s->cur_pic.mb_type[mb_xy];
                  int mv_dir = MV_DIR_FORWARD | MV_DIR_BACKWARD;
  
                  int error = s->error_status_table[mb_xy];
  
                  if (IS_INTRA(mb_type))
                      continue;
                  if (!(error & ER_MV_ERROR))
                      continue; // inter with undamaged MV
                  if (!(error & ER_AC_ERROR))
                      continue; // undamaged inter
  
                  if (!(s->last_pic.f && s->last_pic.f->data[0]))
                      mv_dir &= ~MV_DIR_FORWARD;
                  if (!(s->next_pic.f && s->next_pic.f->data[0]))
                      mv_dir &= ~MV_DIR_BACKWARD;
  
                  if (s->pp_time) {
                      int time_pp = s->pp_time;
                      int time_pb = s->pb_time;
  
                      av_assert0(s->avctx->codec_id != AV_CODEC_ID_H264);
                      ff_thread_await_progress(s->next_pic.tf, mb_y, 0);
  
                      s->mv[0][0][0] = s->next_pic.motion_val[0][xy][0] *  time_pb            / time_pp;
                      s->mv[0][0][1] = s->next_pic.motion_val[0][xy][1] *  time_pb            / time_pp;
                      s->mv[1][0][0] = s->next_pic.motion_val[0][xy][0] * (time_pb - time_pp) / time_pp;
                      s->mv[1][0][1] = s->next_pic.motion_val[0][xy][1] * (time_pb - time_pp) / time_pp;
                  } else {
                      s->mv[0][0][0] = 0;
                      s->mv[0][0][1] = 0;
                      s->mv[1][0][0] = 0;
                      s->mv[1][0][1] = 0;
                  }
  
                  s->decode_mb(s->opaque, 0, mv_dir, MV_TYPE_16X16, &s->mv,
                               mb_x, mb_y, 0, 0);
              }
          }
      } else
          guess_mv(s);
  
      /* the filters below manipulate raw image, skip them */
      if (CONFIG_XVMC && s->avctx->hwaccel && s->avctx->hwaccel->decode_mb)
          goto ec_clean;
      /* fill DC for inter blocks */
      for (mb_y = 0; mb_y < s->mb_height; mb_y++) {
          for (mb_x = 0; mb_x < s->mb_width; mb_x++) {
              int dc, dcu, dcv, y, n;
              int16_t *dc_ptr;
              uint8_t *dest_y, *dest_cb, *dest_cr;
              const int mb_xy   = mb_x + mb_y * s->mb_stride;
              const int mb_type = s->cur_pic.mb_type[mb_xy];
  
              // error = s->error_status_table[mb_xy];
  
              if (IS_INTRA(mb_type) && s->partitioned_frame)
                  continue;
              // if (error & ER_MV_ERROR)
              //     continue; // inter data damaged FIXME is this good?
  
              dest_y  = s->cur_pic.f->data[0] + mb_x * 16 + mb_y * 16 * linesize[0];
              dest_cb = s->cur_pic.f->data[1] + mb_x *  8 + mb_y *  8 * linesize[1];
              dest_cr = s->cur_pic.f->data[2] + mb_x *  8 + mb_y *  8 * linesize[2];
  
              dc_ptr = &s->dc_val[0][mb_x * 2 + mb_y * 2 * s->b8_stride];
              for (n = 0; n < 4; n++) {
                  dc = 0;
                  for (y = 0; y < 8; y++) {
                      int x;
                      for (x = 0; x < 8; x++)
                         dc += dest_y[x + (n & 1) * 8 +
                               (y + (n >> 1) * 8) * linesize[0]];
                  }
                  dc_ptr[(n & 1) + (n >> 1) * s->b8_stride] = (dc + 4) >> 3;
              }
  
              if (!s->cur_pic.f->data[2])
                  continue;
  
              dcu = dcv = 0;
              for (y = 0; y < 8; y++) {
                  int x;
                  for (x = 0; x < 8; x++) {
                      dcu += dest_cb[x + y * linesize[1]];
                      dcv += dest_cr[x + y * linesize[2]];
                  }
              }
              s->dc_val[1][mb_x + mb_y * s->mb_stride] = (dcu + 4) >> 3;
              s->dc_val[2][mb_x + mb_y * s->mb_stride] = (dcv + 4) >> 3;
          }
      }
  #if 1
      /* guess DC for damaged blocks */
      guess_dc(s, s->dc_val[0], s->mb_width*2, s->mb_height*2, s->b8_stride, 1);
      guess_dc(s, s->dc_val[1], s->mb_width  , s->mb_height  , s->mb_stride, 0);
      guess_dc(s, s->dc_val[2], s->mb_width  , s->mb_height  , s->mb_stride, 0);
  #endif
  
      /* filter luma DC */
      filter181(s->dc_val[0], s->mb_width * 2, s->mb_height * 2, s->b8_stride);
  
  #if 1
      /* render DC only intra */
      for (mb_y = 0; mb_y < s->mb_height; mb_y++) {
          for (mb_x = 0; mb_x < s->mb_width; mb_x++) {
              uint8_t *dest_y, *dest_cb, *dest_cr;
              const int mb_xy   = mb_x + mb_y * s->mb_stride;
              const int mb_type = s->cur_pic.mb_type[mb_xy];
  
              int error = s->error_status_table[mb_xy];
  
              if (IS_INTER(mb_type))
                  continue;
              if (!(error & ER_AC_ERROR))
                  continue; // undamaged
  
              dest_y  = s->cur_pic.f->data[0] + mb_x * 16 + mb_y * 16 * linesize[0];
              dest_cb = s->cur_pic.f->data[1] + mb_x *  8 + mb_y *  8 * linesize[1];
              dest_cr = s->cur_pic.f->data[2] + mb_x *  8 + mb_y *  8 * linesize[2];
              if (!s->cur_pic.f->data[2])
                  dest_cb = dest_cr = NULL;
  
              put_dc(s, dest_y, dest_cb, dest_cr, mb_x, mb_y);
          }
      }
  #endif
  
      if (s->avctx->error_concealment & FF_EC_DEBLOCK) {
          /* filter horizontal block boundaries */
          h_block_filter(s, s->cur_pic.f->data[0], s->mb_width * 2,
                         s->mb_height * 2, linesize[0], 1);
  
          /* filter vertical block boundaries */
          v_block_filter(s, s->cur_pic.f->data[0], s->mb_width * 2,
                         s->mb_height * 2, linesize[0], 1);
  
          if (s->cur_pic.f->data[2]) {
              h_block_filter(s, s->cur_pic.f->data[1], s->mb_width,
                          s->mb_height, linesize[1], 0);
              h_block_filter(s, s->cur_pic.f->data[2], s->mb_width,
                          s->mb_height, linesize[2], 0);
              v_block_filter(s, s->cur_pic.f->data[1], s->mb_width,
                          s->mb_height, linesize[1], 0);
              v_block_filter(s, s->cur_pic.f->data[2], s->mb_width,
                          s->mb_height, linesize[2], 0);
          }
      }
  
  ec_clean:
      /* clean a few tables */
      for (i = 0; i < s->mb_num; i++) {
          const int mb_xy = s->mb_index2xy[i];
          int       error = s->error_status_table[mb_xy];
  
          if (s->mbskip_table && s->cur_pic.f->pict_type != AV_PICTURE_TYPE_B &&
              (error & (ER_DC_ERROR | ER_MV_ERROR | ER_AC_ERROR))) {
              s->mbskip_table[mb_xy] = 0;
          }
          if (s->mbintra_table)
              s->mbintra_table[mb_xy] = 1;
      }
  
      for (i = 0; i < 2; i++) {
          av_buffer_unref(&s->ref_index_buf[i]);
          av_buffer_unref(&s->motion_val_buf[i]);
          s->cur_pic.ref_index[i]  = NULL;
          s->cur_pic.motion_val[i] = NULL;
      }
  
      memset(&s->cur_pic, 0, sizeof(ERPicture));
      memset(&s->last_pic, 0, sizeof(ERPicture));
      memset(&s->next_pic, 0, sizeof(ERPicture));
  }
  