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FFmpeg/libavcodec/error_resilience.c
Michael Niedermayer bf36dc50ea Merge commit '578ea75a9e4ac56e0bbbbe668700be756aa699f8' 
* commit '578ea75a9e4ac56e0bbbbe668700be756aa699f8':
  vdpau: remove old-style decoders

Conflicts:
	libavcodec/allcodecs.c
	libavcodec/h263dec.c
	libavcodec/h264.c
	libavcodec/mpeg12dec.c
	libavcodec/mpeg4videodec.c
	libavcodec/vc1dec.c
	libavcodec/vdpau.c

Merged-by: Michael Niedermayer <michaelni@gmx.at>
2013-08-06 13:24:22 +02:00

1275 lines
48 KiB
C
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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 "error_resilience.h"
#include "mpegvideo.h"
#include "rectangle.h"
#include "thread.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, int *mv_step, int *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;
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, 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(ERContext *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);
uint32_t (*dist)[4] = av_malloc(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, int stride, int is_luma)
{
int b_x, b_y, mvx_stride, mvy_stride;
const 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->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,
int stride, int is_luma)
{
int b_x, b_y, mvx_stride, mvy_stride;
const 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->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)];
}
}
}
}
}
static void guess_mv(ERContext *s)
{
uint8_t *fixed = s->er_temp_buffer;
#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->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 <= 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;
int mv_dir = (s->last_pic && 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;
}
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;
av_assert1(!IS_INTRA(s->cur_pic->mb_type[mb_xy]));
av_assert1(s->last_pic && s->last_pic->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->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]) {
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]) {
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]) {
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 */
pred_count++;
if (!fixed[mb_xy] && 0) {
if (s->avctx->codec_id == AV_CODEC_ID_H264) {
// FIXME
} else {
ff_thread_await_progress(&s->last_pic->tf,
mb_y, 0);
}
if (!s->last_pic->motion_val[0] ||
!s->last_pic->ref_index[0])
goto skip_last_mv;
prev_x = s->last_pic->motion_val[0][mot_index][0];
prev_y = s->last_pic->motion_val[0][mot_index][1];
prev_ref = s->last_pic->ref_index[0][4 * mb_xy];
} else {
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++;
skip_last_mv:
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]) {
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]) {
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]) {
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]) {
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;
for (i = 0; i < s->mb_num; i++) {
int mb_xy = s->mb_index2xy[i];
if (fixed[mb_xy])
fixed[mb_xy] = MV_FROZEN;
}
}
}
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 || !s->last_pic->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->avctx->codec_id == AV_CODEC_ID_H264 && s->ref_count <= 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->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->dsp->sad[0](NULL, last_mb_ptr, mb_ptr,
linesize[0], 16);
// FIXME need await_progress() here
is_intra_likely -= s->dsp->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--;
}
}
}
// printf("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->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(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)
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->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->active_thread_type & FF_THREAD_SLICE) &&
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;
s->error_count = INT_MAX;
}
}
}
void ff_er_frame_end(ERContext *s)
{
int *linesize = s->cur_pic->f.linesize;
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->err_recognition || s->error_count == 0 ||
s->avctx->lowres ||
s->avctx->hwaccel ||
!s->cur_pic || s->cur_pic->field_picture ||
s->error_count == 3 * s->mb_width *
(s->avctx->skip_top + s->avctx->skip_bottom)) {
return;
}
if (s->last_pic) {
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");
s->last_pic = NULL;
}
}
if (s->next_pic) {
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");
s->next_pic = NULL;
}
}
if (s->cur_pic->motion_val[0] == NULL) {
av_log(s->avctx, AV_LOG_ERROR, "Warning MVs not available\n");
for (i = 0; i < 2; i++) {
s->cur_pic->ref_index_buf[i] = av_buffer_allocz(s->mb_stride * s->mb_height * 4 * sizeof(uint8_t));
s->cur_pic->motion_val_buf[i] = av_buffer_allocz((size + 4) * 2 * sizeof(uint16_t));
if (!s->cur_pic->ref_index_buf[i] || !s->cur_pic->motion_val_buf[i])
break;
s->cur_pic->ref_index[i] = s->cur_pic->ref_index_buf[i]->data;
s->cur_pic->motion_val[i] = (int16_t (*)[2])s->cur_pic->motion_val_buf[i]->data + 4;
}
if (i < 2) {
for (i = 0; i < 2; i++) {
av_buffer_unref(&s->cur_pic->ref_index_buf[i]);
av_buffer_unref(&s->cur_pic->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[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 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];
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 && s->last_pic->f.data[0]) &&
!(s->next_pic && 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 && s->last_pic->f.data[0]);
const int mv_dir = dir ? MV_DIR_BACKWARD : MV_DIR_FORWARD;
int mv_type;
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 h264 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;
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 && s->last_pic->f.data[0]))
mv_dir &= ~MV_DIR_FORWARD;
if (!(s->next_pic && 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 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->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;
}
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];
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];
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);
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);
/* 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);
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->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;
}
s->mbintra_table[mb_xy] = 1;
}
s->cur_pic = NULL;
s->next_pic = NULL;
s->last_pic = NULL;
}
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