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FFmpeg/libavcodec/error_resilience.c
Michael Niedermayer 7d8f115843 Merge remote-tracking branch 'qatar/master' 
* qatar/master:
  mpegenc: use avctx->slices as number of slices
  v410enc: fix undefined signed left shift caused by integer promotion
  Release notes: mention cleaned up header includes
  fix Changelog file
  Fix a bunch of typos.
  Drop some pointless void* return value casts from av_malloc() invocations.
  wavpack: fix typos in previous cosmetic clean-up commit
  wavpack: cosmetics: K&R pretty-printing
  avconv: remove the 'codec framerate is different from stream' warning
  wavpack: determine sample_fmt before requesting a buffer
  bmv audio: implement new audio decoding API
  mpegaudiodec: skip all channels when skipping granules
  mpegenc: simplify muxrate calculation

Conflicts:
	Changelog
	avconv.c
	doc/RELEASE_NOTES
	libavcodec/h264.c
	libavcodec/mpeg12.c
	libavcodec/mpegaudiodec.c
	libavcodec/mpegvideo.c
	libavformat/mpegenc.c

Merged-by: Michael Niedermayer <michaelni@gmx.at>
2012-01-03 03:06:45 +01:00

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/*
* 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 "avcodec.h"
#include "dsputil.h"
#include "mpegvideo.h"
#include "h264.h"
#include "rectangle.h"
#include "thread.h"
/*
* H264 redefines mb_intra so it is not mistakely used (its uninitialized in h264)
* but error concealment must support both h264 and h263 thus we must undo this
*/
#undef mb_intra
static void decode_mb(MpegEncContext *s, int ref){
s->dest[0] = s->current_picture.f.data[0] + (s->mb_y * 16 * s->linesize) + s->mb_x * 16;
s->dest[1] = s->current_picture.f.data[1] + (s->mb_y * (16 >> s->chroma_y_shift) * s->uvlinesize) + s->mb_x * (16 >> s->chroma_x_shift);
s->dest[2] = s->current_picture.f.data[2] + (s->mb_y * (16 >> s->chroma_y_shift) * s->uvlinesize) + s->mb_x * (16 >> s->chroma_x_shift);
if(CONFIG_H264_DECODER && s->codec_id == CODEC_ID_H264){
H264Context *h= (void*)s;
h->mb_xy= s->mb_x + s->mb_y*s->mb_stride;
memset(h->non_zero_count_cache, 0, sizeof(h->non_zero_count_cache));
assert(ref>=0);
/* FIXME: It is posible albeit uncommon that slice references
* differ between slices. We take the easy approach and ignore
* it for now. If this turns out to have any relevance in
* practice then correct remapping should be added. */
if (ref >= h->ref_count[0])
ref=0;
fill_rectangle(&s->current_picture.f.ref_index[0][4*h->mb_xy], 2, 2, 2, ref, 1);
fill_rectangle(&h->ref_cache[0][scan8[0]], 4, 4, 8, ref, 1);
fill_rectangle(h->mv_cache[0][ scan8[0] ], 4, 4, 8, pack16to32(s->mv[0][0][0],s->mv[0][0][1]), 4);
assert(!FRAME_MBAFF);
ff_h264_hl_decode_mb(h);
}else{
assert(ref==0);
MPV_decode_mb(s, s->block);
}
}
/**
* @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(MpegEncContext *s, int *mv_step, int *stride){
if(s->codec_id == CODEC_ID_H264){
H264Context *h= (void*)s;
assert(s->quarter_sample);
*mv_step= 4;
*stride= h->b_stride;
}else{
*mv_step= 2;
*stride= s->b8_stride;
}
}
/**
* Replace the current MB with a flat dc-only version.
*/
static void put_dc(MpegEncContext *s, uint8_t *dest_y, uint8_t *dest_cb, uint8_t *dest_cr, int mb_x, int mb_y)
{
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)*s->linesize]= 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;
for(y=0; y<8; y++){
int x;
for(x=0; x<8; x++){
dest_cb[x + y*(s->uvlinesize)]= dcu/8;
dest_cr[x + y*(s->uvlinesize)]= dcv/8;
}
}
}
static void filter181(int16_t *data, int width, int height, int 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= (dc*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= (dc*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(MpegEncContext *s, int16_t *dc, int w, int h, int stride, int is_luma){
int b_x, b_y;
int16_t (*col )[4] = av_malloc(stride*h*sizeof( int16_t)*4);
uint16_t (*dist)[4] = av_malloc(stride*h*sizeof(uint16_t)*4);
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->current_picture.f.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->current_picture.f.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->current_picture.f.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->current_picture.f.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->current_picture.f.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/dist[b_x + b_y*stride][j];
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;
}
}
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(MpegEncContext *s, uint8_t *dst, int w, int h, int stride, int is_luma){
int b_x, b_y, mvx_stride, mvy_stride;
uint8_t *cm = ff_cropTbl + 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->current_picture.f.mb_type[( b_x >> is_luma) + (b_y >> is_luma) * s->mb_stride]);
int right_intra = IS_INTRA(s->current_picture.f.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->current_picture.f.motion_val[0][mvy_stride*b_y + mvx_stride* b_x ];
int16_t *right_mv= s->current_picture.f.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(MpegEncContext *s, uint8_t *dst, int w, int h, int stride, int is_luma){
int b_x, b_y, mvx_stride, mvy_stride;
uint8_t *cm = ff_cropTbl + 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->current_picture.f.mb_type[(b_x >> is_luma) + ( b_y >> is_luma) * s->mb_stride]);
int bottom_intra = IS_INTRA(s->current_picture.f.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->current_picture.f.motion_val[0][mvy_stride * b_y + mvx_stride * b_x];
int16_t *bottom_mv = s->current_picture.f.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)];
}
}
}
}
}
static void guess_mv(MpegEncContext *s){
uint8_t *fixed = av_malloc(s->mb_stride * s->mb_height);
#define MV_FROZEN 3
#define MV_CHANGED 2
#define MV_UNCHANGED 1
const int mb_stride = s->mb_stride;
const int mb_width = s->mb_width;
const int mb_height= s->mb_height;
int i, depth, num_avail;
int mb_x, mb_y, mot_step, mot_stride;
set_mv_strides(s, &mot_step, &mot_stride);
num_avail=0;
for(i=0; i<s->mb_num; i++){
const int mb_xy= s->mb_index2xy[ i ];
int f=0;
int error= s->error_status_table[mb_xy];
if(IS_INTRA(s->current_picture.f.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_picture.f.data[0] && s->last_picture.f.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->current_picture.f.motion_val[0][mot_index][0]= s->last_picture.f.motion_val[0][mot_index][0];
s->current_picture.f.motion_val[0][mot_index][1]= s->last_picture.f.motion_val[0][mot_index][1];
s->current_picture.f.ref_index[0][4*mb_xy] = s->last_picture.f.ref_index[0][4*mb_xy];
}
}
if((!(s->avctx->error_concealment&FF_EC_GUESS_MVS)) || num_avail <= mb_width/2){
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;
if(IS_INTRA(s->current_picture.f.mb_type[mb_xy])) continue;
if(!(s->error_status_table[mb_xy]&ER_MV_ERROR)) continue;
s->mv_dir = s->last_picture.f.data[0] ? MV_DIR_FORWARD : MV_DIR_BACKWARD;
s->mb_intra=0;
s->mv_type = MV_TYPE_16X16;
s->mb_skipped=0;
s->dsp.clear_blocks(s->block[0]);
s->mb_x= mb_x;
s->mb_y= mb_y;
s->mv[0][0][0]= 0;
s->mv[0][0][1]= 0;
decode_mb(s, 0);
}
}
goto end;
}
for(depth=0;; depth++){
int changed, pass, none_left;
none_left=1;
changed=1;
for(pass=0; (changed || pass<2) && pass<10; pass++){
int mb_x, mb_y;
int score_sum=0;
changed=0;
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;
int mv_predictor[8][2]={{0}};
int ref[8]={0};
int pred_count=0;
int j;
int best_score=256*256*256*64;
int best_pred=0;
const int mot_index= (mb_x + mb_y*mot_stride) * mot_step;
int prev_x, prev_y, prev_ref;
if((mb_x^mb_y^pass)&1) continue;
if(fixed[mb_xy]==MV_FROZEN) continue;
assert(!IS_INTRA(s->current_picture.f.mb_type[mb_xy]));
assert(s->last_picture_ptr && s->last_picture_ptr->f.data[0]);
j=0;
if(mb_x>0 && fixed[mb_xy-1 ]==MV_FROZEN) j=1;
if(mb_x+1<mb_width && fixed[mb_xy+1 ]==MV_FROZEN) j=1;
if(mb_y>0 && fixed[mb_xy-mb_stride]==MV_FROZEN) j=1;
if(mb_y+1<mb_height && fixed[mb_xy+mb_stride]==MV_FROZEN) j=1;
if(j==0) continue;
j=0;
if(mb_x>0 && fixed[mb_xy-1 ]==MV_CHANGED) j=1;
if(mb_x+1<mb_width && fixed[mb_xy+1 ]==MV_CHANGED) j=1;
if(mb_y>0 && fixed[mb_xy-mb_stride]==MV_CHANGED) j=1;
if(mb_y+1<mb_height && fixed[mb_xy+mb_stride]==MV_CHANGED) j=1;
if(j==0 && pass>1) continue;
none_left=0;
if(mb_x>0 && fixed[mb_xy-1]){
mv_predictor[pred_count][0]= s->current_picture.f.motion_val[0][mot_index - mot_step][0];
mv_predictor[pred_count][1]= s->current_picture.f.motion_val[0][mot_index - mot_step][1];
ref [pred_count] = s->current_picture.f.ref_index[0][4*(mb_xy-1)];
pred_count++;
}
if(mb_x+1<mb_width && fixed[mb_xy+1]){
mv_predictor[pred_count][0]= s->current_picture.f.motion_val[0][mot_index + mot_step][0];
mv_predictor[pred_count][1]= s->current_picture.f.motion_val[0][mot_index + mot_step][1];
ref [pred_count] = s->current_picture.f.ref_index[0][4*(mb_xy+1)];
pred_count++;
}
if(mb_y>0 && fixed[mb_xy-mb_stride]){
mv_predictor[pred_count][0]= s->current_picture.f.motion_val[0][mot_index - mot_stride*mot_step][0];
mv_predictor[pred_count][1]= s->current_picture.f.motion_val[0][mot_index - mot_stride*mot_step][1];
ref [pred_count] = s->current_picture.f.ref_index[0][4*(mb_xy-s->mb_stride)];
pred_count++;
}
if(mb_y+1<mb_height && fixed[mb_xy+mb_stride]){
mv_predictor[pred_count][0]= s->current_picture.f.motion_val[0][mot_index + mot_stride*mot_step][0];
mv_predictor[pred_count][1]= s->current_picture.f.motion_val[0][mot_index + mot_stride*mot_step][1];
ref [pred_count] = s->current_picture.f.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 */
pred_count++;
if (!fixed[mb_xy] && 0) {
if (s->avctx->codec_id == CODEC_ID_H264) {
// FIXME
} else {
ff_thread_await_progress((AVFrame *) s->last_picture_ptr,
mb_y, 0);
}
if (!s->last_picture.f.motion_val[0] ||
!s->last_picture.f.ref_index[0])
goto skip_last_mv;
prev_x = s->last_picture.f.motion_val[0][mot_index][0];
prev_y = s->last_picture.f.motion_val[0][mot_index][1];
prev_ref = s->last_picture.f.ref_index[0][4*mb_xy];
} else {
prev_x = s->current_picture.f.motion_val[0][mot_index][0];
prev_y = s->current_picture.f.motion_val[0][mot_index][1];
prev_ref = s->current_picture.f.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++;
skip_last_mv:
s->mv_dir = MV_DIR_FORWARD;
s->mb_intra=0;
s->mv_type = MV_TYPE_16X16;
s->mb_skipped=0;
s->dsp.clear_blocks(s->block[0]);
s->mb_x= mb_x;
s->mb_y= mb_y;
for(j=0; j<pred_count; j++){
int score=0;
uint8_t *src = s->current_picture.f.data[0] + mb_x*16 + mb_y*16*s->linesize;
s->current_picture.f.motion_val[0][mot_index][0] = s->mv[0][0][0] = mv_predictor[j][0];
s->current_picture.f.motion_val[0][mot_index][1] = s->mv[0][0][1] = mv_predictor[j][1];
if(ref[j]<0) //predictor intra or otherwise not available
continue;
decode_mb(s, ref[j]);
if(mb_x>0 && fixed[mb_xy-1]){
int k;
for(k=0; k<16; k++)
score += FFABS(src[k*s->linesize-1 ]-src[k*s->linesize ]);
}
if(mb_x+1<mb_width && fixed[mb_xy+1]){
int k;
for(k=0; k<16; k++)
score += FFABS(src[k*s->linesize+15]-src[k*s->linesize+16]);
}
if(mb_y>0 && fixed[mb_xy-mb_stride]){
int k;
for(k=0; k<16; k++)
score += FFABS(src[k-s->linesize ]-src[k ]);
}
if(mb_y+1<mb_height && fixed[mb_xy+mb_stride]){
int k;
for(k=0; k<16; k++)
score += FFABS(src[k+s->linesize*15]-src[k+s->linesize*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->current_picture.f.motion_val[0][mot_index + i + j * mot_stride][0] = s->mv[0][0][0];
s->current_picture.f.motion_val[0][mot_index + i + j * mot_stride][1] = s->mv[0][0][1];
}
decode_mb(s, ref[best_pred]);
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;
}
}
// printf(".%d/%d", changed, score_sum); fflush(stdout);
}
if(none_left)
goto end;
for(i=0; i<s->mb_num; i++){
int mb_xy= s->mb_index2xy[i];
if(fixed[mb_xy])
fixed[mb_xy]=MV_FROZEN;
}
// printf(":"); fflush(stdout);
}
end:
av_free(fixed);
}
static int is_intra_more_likely(MpegEncContext *s){
int is_intra_likely, i, j, undamaged_count, skip_amount, mb_x, mb_y;
if (!s->last_picture_ptr || !s->last_picture_ptr->f.data[0]) return 1; //no previous frame available -> use spatial prediction
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(s->codec_id == CODEC_ID_H264){
H264Context *h= (void*)s;
if (h->list_count <= 0 || h->ref_count[0] <= 0 || !h->ref_list[0][0].f.data[0])
return 1;
}
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_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration && s->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++;
if((j%skip_amount) != 0) continue; //skip a few to speed things up
if(s->pict_type==AV_PICTURE_TYPE_I){
uint8_t *mb_ptr = s->current_picture.f.data[0] + mb_x*16 + mb_y*16*s->linesize;
uint8_t *last_mb_ptr= s->last_picture.f.data [0] + mb_x*16 + mb_y*16*s->linesize;
if (s->avctx->codec_id == CODEC_ID_H264) {
// FIXME
} else {
ff_thread_await_progress((AVFrame *) s->last_picture_ptr,
mb_y, 0);
}
is_intra_likely += s->dsp.sad[0](NULL, last_mb_ptr, mb_ptr , s->linesize, 16);
// FIXME need await_progress() here
is_intra_likely -= s->dsp.sad[0](NULL, last_mb_ptr, last_mb_ptr+s->linesize*16, s->linesize, 16);
}else{
if (IS_INTRA(s->current_picture.f.mb_type[mb_xy]))
is_intra_likely++;
else
is_intra_likely--;
}
}
}
//printf("is_intra_likely: %d type:%d\n", is_intra_likely, s->pict_type);
return is_intra_likely > 0;
}
void ff_er_frame_start(MpegEncContext *s){
if(!s->err_recognition) return;
memset(s->error_status_table, ER_MB_ERROR|VP_START|ER_MB_END, s->mb_stride*s->mb_height*sizeof(uint8_t));
s->error_count= 3*s->mb_num;
s->error_occurred = 0;
}
/**
* 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(MpegEncContext *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)
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->err_recognition) return;
mask &= ~VP_START;
if(status & (ER_AC_ERROR|ER_AC_END)){
mask &= ~(ER_AC_ERROR|ER_AC_END);
s->error_count -= end_i - start_i + 1;
}
if(status & (ER_DC_ERROR|ER_DC_END)){
mask &= ~(ER_DC_ERROR|ER_DC_END);
s->error_count -= end_i - start_i + 1;
}
if(status & (ER_MV_ERROR|ER_MV_END)){
mask &= ~(ER_MV_ERROR|ER_MV_END);
s->error_count -= end_i - start_i + 1;
}
if(status & ER_MB_ERROR) {
s->error_occurred = 1;
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)
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->thread_count <= 1 && 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_count= INT_MAX;
}
}
void ff_er_frame_end(MpegEncContext *s){
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;
Picture *pic= s->current_picture_ptr;
if(!s->err_recognition || s->error_count==0 || s->avctx->lowres ||
s->avctx->hwaccel ||
s->avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU ||
s->picture_structure != PICT_FRAME || // we do not support ER of field pictures yet, though it should not crash if enabled
s->error_count==3*s->mb_width*(s->avctx->skip_top + s->avctx->skip_bottom)) return;
if (s->current_picture.f.motion_val[0] == NULL) {
av_log(s->avctx, AV_LOG_ERROR, "Warning MVs not available\n");
for(i=0; i<2; i++){
pic->f.ref_index[i] = av_mallocz(s->mb_stride * s->mb_height * 4 * sizeof(uint8_t));
pic->motion_val_base[i]= av_mallocz((size+4) * 2 * sizeof(uint16_t));
pic->f.motion_val[i] = pic->motion_val_base[i] + 4;
}
pic->f.motion_subsample_log2 = 3;
s->current_picture= *s->current_picture_ptr;
}
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->err_recognition&AV_EF_EXPLODE){
int end_ok=1;
for(i=s->mb_num-2; i>=s->mb_width+100; i--){ //FIXME +100 hack
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[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];
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];
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\n", dc_error, ac_error, mv_error);
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];
error= s->error_status_table[mb_xy];
if(!((error&ER_DC_ERROR) && (error&ER_MV_ERROR)))
continue;
if(is_intra_likely)
s->current_picture.f.mb_type[mb_xy] = MB_TYPE_INTRA4x4;
else
s->current_picture.f.mb_type[mb_xy] = MB_TYPE_16x16 | MB_TYPE_L0;
}
// change inter to intra blocks if no reference frames are available
if (!s->last_picture.f.data[0] && !s->next_picture.f.data[0])
for(i=0; i<s->mb_num; i++){
const int mb_xy= s->mb_index2xy[i];
if (!IS_INTRA(s->current_picture.f.mb_type[mb_xy]))
s->current_picture.f.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->current_picture.f.mb_type[mb_xy];
int dir = !s->last_picture.f.data[0];
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
s->mv_dir = dir ? MV_DIR_BACKWARD : MV_DIR_FORWARD;
s->mb_intra=0;
s->mb_skipped=0;
if(IS_8X8(mb_type)){
int mb_index= mb_x*2 + mb_y*2*s->b8_stride;
int j;
s->mv_type = MV_TYPE_8X8;
for(j=0; j<4; j++){
s->mv[0][j][0] = s->current_picture.f.motion_val[dir][mb_index + (j & 1) + (j >> 1) * s->b8_stride][0];
s->mv[0][j][1] = s->current_picture.f.motion_val[dir][mb_index + (j & 1) + (j >> 1) * s->b8_stride][1];
}
}else{
s->mv_type = MV_TYPE_16X16;
s->mv[0][0][0] = s->current_picture.f.motion_val[dir][ mb_x*2 + mb_y*2*s->b8_stride ][0];
s->mv[0][0][1] = s->current_picture.f.motion_val[dir][ mb_x*2 + mb_y*2*s->b8_stride ][1];
}
s->dsp.clear_blocks(s->block[0]);
s->mb_x= mb_x;
s->mb_y= mb_y;
decode_mb(s, 0/*FIXME h264 partitioned slices need this set*/);
}
}
/* guess MVs */
if(s->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->current_picture.f.mb_type[mb_xy];
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
s->mv_dir = MV_DIR_FORWARD|MV_DIR_BACKWARD;
if(!s->last_picture.f.data[0]) s->mv_dir &= ~MV_DIR_FORWARD;
if(!s->next_picture.f.data[0]) s->mv_dir &= ~MV_DIR_BACKWARD;
s->mb_intra=0;
s->mv_type = MV_TYPE_16X16;
s->mb_skipped=0;
if(s->pp_time){
int time_pp= s->pp_time;
int time_pb= s->pb_time;
if (s->avctx->codec_id == CODEC_ID_H264) {
//FIXME
} else {
ff_thread_await_progress((AVFrame *) s->next_picture_ptr,
mb_y, 0);
}
s->mv[0][0][0] = s->next_picture.f.motion_val[0][xy][0] * time_pb / time_pp;
s->mv[0][0][1] = s->next_picture.f.motion_val[0][xy][1] * time_pb / time_pp;
s->mv[1][0][0] = s->next_picture.f.motion_val[0][xy][0] * (time_pb - time_pp) / time_pp;
s->mv[1][0][1] = s->next_picture.f.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->dsp.clear_blocks(s->block[0]);
s->mb_x= mb_x;
s->mb_y= mb_y;
decode_mb(s, 0);
}
}
}else
guess_mv(s);
/* the filters below are not XvMC compatible, skip them */
if(CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration)
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->current_picture.f.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->current_picture.f.data[0] + mb_x * 16 + mb_y * 16 * s->linesize;
dest_cb = s->current_picture.f.data[1] + mb_x * 8 + mb_y * 8 * s->uvlinesize;
dest_cr = s->current_picture.f.data[2] + mb_x * 8 + mb_y * 8 * s->uvlinesize;
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)*s->linesize];
}
}
dc_ptr[(n&1) + (n>>1)*s->b8_stride]= (dc+4)>>3;
}
dcu=dcv=0;
for(y=0; y<8; y++){
int x;
for(x=0; x<8; x++){
dcu+=dest_cb[x + y*(s->uvlinesize)];
dcv+=dest_cr[x + y*(s->uvlinesize)];
}
}
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->current_picture.f.mb_type[mb_xy];
error= s->error_status_table[mb_xy];
if(IS_INTER(mb_type)) continue;
if(!(error&ER_AC_ERROR)) continue; //undamaged
dest_y = s->current_picture.f.data[0] + mb_x * 16 + mb_y * 16 * s->linesize;
dest_cb = s->current_picture.f.data[1] + mb_x * 8 + mb_y * 8 * s->uvlinesize;
dest_cr = s->current_picture.f.data[2] + mb_x * 8 + mb_y * 8 * s->uvlinesize;
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->current_picture.f.data[0], s->mb_width*2, s->mb_height*2, s->linesize , 1);
h_block_filter(s, s->current_picture.f.data[1], s->mb_width , s->mb_height , s->uvlinesize, 0);
h_block_filter(s, s->current_picture.f.data[2], s->mb_width , s->mb_height , s->uvlinesize, 0);
/* filter vertical block boundaries */
v_block_filter(s, s->current_picture.f.data[0], s->mb_width*2, s->mb_height*2, s->linesize , 1);
v_block_filter(s, s->current_picture.f.data[1], s->mb_width , s->mb_height , s->uvlinesize, 0);
v_block_filter(s, s->current_picture.f.data[2], s->mb_width , s->mb_height , s->uvlinesize, 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->pict_type!=AV_PICTURE_TYPE_B && (error&(ER_DC_ERROR|ER_MV_ERROR|ER_AC_ERROR))){
s->mbskip_table[mb_xy]=0;
}
s->mbintra_table[mb_xy]=1;
}
}
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