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ffmpeg/libavcodec/h263dec.c

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/*
* H263 decoder
* Copyright (c) 2001 Fabrice Bellard.
*
* This library 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 of the License, or (at your option) any later version.
*
* This library 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 this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "avcodec.h"
#include "dsputil.h"
#include "mpegvideo.h"
#if 1
#define PRINT_QP(a, b) {}
#else
#define PRINT_QP(a, b) printf(a, b)
#endif
//#define DEBUG
//#define PRINT_FRAME_TIME
#ifdef PRINT_FRAME_TIME
static inline long long rdtsc()
{
long long l;
asm volatile( "rdtsc\n\t"
: "=A" (l)
);
// printf("%d\n", int(l/1000));
return l;
}
#endif
static int h263_decode_init(AVCodecContext *avctx)
{
MpegEncContext *s = avctx->priv_data;
s->avctx = avctx;
s->out_format = FMT_H263;
s->width = avctx->width;
s->height = avctx->height;
s->workaround_bugs= avctx->workaround_bugs;
// set defaults
s->quant_precision=5;
s->progressive_sequence=1;
s->decode_mb= ff_h263_decode_mb;
/* select sub codec */
switch(avctx->codec->id) {
case CODEC_ID_H263:
s->gob_number = 0;
break;
case CODEC_ID_MPEG4:
s->time_increment_bits = 4; /* default value for broken headers */
s->h263_pred = 1;
s->has_b_frames = 1; //default, might be overriden in the vol header during header parsing
break;
case CODEC_ID_MSMPEG4V1:
s->h263_msmpeg4 = 1;
s->h263_pred = 1;
s->msmpeg4_version=1;
break;
case CODEC_ID_MSMPEG4V2:
s->h263_msmpeg4 = 1;
s->h263_pred = 1;
s->msmpeg4_version=2;
break;
case CODEC_ID_MSMPEG4V3:
s->h263_msmpeg4 = 1;
s->h263_pred = 1;
s->msmpeg4_version=3;
break;
case CODEC_ID_WMV1:
s->h263_msmpeg4 = 1;
s->h263_pred = 1;
s->msmpeg4_version=4;
break;
case CODEC_ID_WMV2:
s->h263_msmpeg4 = 1;
s->h263_pred = 1;
s->msmpeg4_version=5;
break;
case CODEC_ID_H263I:
s->h263_intel = 1;
break;
default:
return -1;
}
s->codec_id= avctx->codec->id;
/* for h263, we allocate the images after having read the header */
if (avctx->codec->id != CODEC_ID_H263 && avctx->codec->id != CODEC_ID_MPEG4)
if (MPV_common_init(s) < 0)
return -1;
if (s->h263_msmpeg4)
ff_msmpeg4_decode_init(s);
else
h263_decode_init_vlc(s);
return 0;
}
static int h263_decode_end(AVCodecContext *avctx)
{
MpegEncContext *s = avctx->priv_data;
MPV_common_end(s);
return 0;
}
/**
* retunrs the number of bytes consumed for building the current frame
*/
static int get_consumed_bytes(MpegEncContext *s, int buf_size){
int pos= (get_bits_count(&s->gb)+7)>>3;
if(s->divx_version>=500){
//we would have to scan through the whole buf to handle the weird reordering ...
return buf_size;
}else{
if(pos==0) pos=1; //avoid infinite loops (i doubt thats needed but ...)
if(pos+10>buf_size) pos=buf_size; // oops ;)
return pos;
}
}
static int decode_slice(MpegEncContext *s){
s->last_resync_gb= s->gb;
s->first_slice_line= 1;
s->resync_mb_x= s->mb_x;
s->resync_mb_y= s->mb_y;
s->y_dc_scale= s->y_dc_scale_table[ s->qscale ];
s->c_dc_scale= s->c_dc_scale_table[ s->qscale ];
if(s->partitioned_frame){
const int qscale= s->qscale;
if(s->codec_id==CODEC_ID_MPEG4){
if(ff_mpeg4_decode_partitions(s) < 0)
return -1;
}
/* restore variables which where modified */
s->first_slice_line=1;
s->mb_x= s->resync_mb_x;
s->mb_y= s->resync_mb_y;
s->qscale= qscale;
s->y_dc_scale= s->y_dc_scale_table[ s->qscale ];
s->c_dc_scale= s->c_dc_scale_table[ s->qscale ];
}
for(; s->mb_y < s->mb_height; s->mb_y++) {
/* per-row end of slice checks */
if(s->msmpeg4_version){
if(s->resync_mb_y + s->slice_height == s->mb_y){
const int xy= s->mb_x + s->mb_y*s->mb_width;
s->error_status_table[xy-1]|= AC_END|DC_END|MV_END;
return 0;
}
}
if(s->msmpeg4_version==1){
s->last_dc[0]=
s->last_dc[1]=
s->last_dc[2]= 128;
}
ff_init_block_index(s);
for(; s->mb_x < s->mb_width; s->mb_x++) {
int ret;
ff_update_block_index(s);
if(s->resync_mb_x == s->mb_x && s->resync_mb_y+1 == s->mb_y){
s->first_slice_line=0;
}
/* DCT & quantize */
clear_blocks(s->block[0]);
s->mv_dir = MV_DIR_FORWARD;
s->mv_type = MV_TYPE_16X16;
//printf("%d %d %06X\n", ret, get_bits_count(&s->gb), show_bits(&s->gb, 24));
ret= s->decode_mb(s, s->block);
PRINT_QP("%2d", s->qscale);
MPV_decode_mb(s, s->block);
if(ret<0){
const int xy= s->mb_x + s->mb_y*s->mb_width;
if(ret==SLICE_END){
//printf("%d %d %d %06X\n", s->mb_x, s->mb_y, s->gb.size*8 - get_bits_count(&s->gb), show_bits(&s->gb, 24));
s->error_status_table[xy]|= AC_END;
if(!s->partitioned_frame)
s->error_status_table[xy]|= MV_END|DC_END;
s->padding_bug_score--;
if(++s->mb_x >= s->mb_width){
s->mb_x=0;
ff_draw_horiz_band(s);
s->mb_y++;
}
return 0;
}else if(ret==SLICE_NOEND){
fprintf(stderr,"Slice mismatch at MB: %d\n", xy);
return -1;
}
fprintf(stderr,"Error at MB: %d\n", xy);
s->error_status_table[xy]|= AC_ERROR;
if(!s->partitioned_frame)
s->error_status_table[xy]|= DC_ERROR|MV_ERROR;
return -1;
}
}
ff_draw_horiz_band(s);
PRINT_QP("%s", "\n");
s->mb_x= 0;
}
assert(s->mb_x==0 && s->mb_y==s->mb_height);
/* try to detect the padding bug */
if( s->codec_id==CODEC_ID_MPEG4
&& (s->workaround_bugs&FF_BUG_AUTODETECT)
&& s->gb.size*8 - get_bits_count(&s->gb) >=0
&& s->gb.size*8 - get_bits_count(&s->gb) < 48
&& !s->resync_marker
&& !s->data_partitioning){
const int bits_count= get_bits_count(&s->gb);
const int bits_left = s->gb.size*8 - bits_count;
if(bits_left==0 || bits_left>8){
s->padding_bug_score++;
} else if(bits_left != 1){
int v= show_bits(&s->gb, 8);
v|= 0x7F >> (7-(bits_count&7));
if(v==0x7F)
s->padding_bug_score--;
else
s->padding_bug_score++;
}
if(s->padding_bug_score > -2)
s->workaround_bugs |= FF_BUG_NO_PADDING;
else
s->workaround_bugs &= ~FF_BUG_NO_PADDING;
}
// handle formats which dont have unique end markers
if(s->msmpeg4_version || (s->workaround_bugs&FF_BUG_NO_PADDING)){ //FIXME perhaps solve this more cleanly
int left= s->gb.size*8 - get_bits_count(&s->gb);
int max_extra=7;
/* no markers in M$ crap */
if(s->msmpeg4_version && s->pict_type==I_TYPE)
max_extra+= 17;
/* buggy padding but the frame should still end approximately at the bitstream end */
if((s->workaround_bugs&FF_BUG_NO_PADDING) && s->error_resilience>=3)
max_extra+= 48;
else if((s->workaround_bugs&FF_BUG_NO_PADDING))
max_extra+= 256*256*256*64;
if(left>max_extra){
fprintf(stderr, "discarding %d junk bits at end, next would be %X\n", left, show_bits(&s->gb, 24));
}
else if(left<0){
fprintf(stderr, "overreading %d bits\n", -left);
}else
s->error_status_table[s->mb_num-1]|= AC_END|MV_END|DC_END;
return 0;
}
fprintf(stderr, "slice end not reached but screenspace end (%d left %06X)\n",
s->gb.size*8 - get_bits_count(&s->gb),
show_bits(&s->gb, 24));
return -1;
}
static int h263_decode_frame(AVCodecContext *avctx,
void *data, int *data_size,
UINT8 *buf, int buf_size)
{
MpegEncContext *s = avctx->priv_data;
int ret,i;
AVPicture *pict = data;
#ifdef PRINT_FRAME_TIME
uint64_t time= rdtsc();
#endif
#ifdef DEBUG
printf("*****frame %d size=%d\n", avctx->frame_number, buf_size);
printf("bytes=%x %x %x %x\n", buf[0], buf[1], buf[2], buf[3]);
#endif
s->hurry_up= avctx->hurry_up;
s->error_resilience= avctx->error_resilience;
s->flags= avctx->flags;
*data_size = 0;
/* no supplementary picture */
if (buf_size == 0) {
return 0;
}
retry:
if(s->bitstream_buffer_size && buf_size<20){ //divx 5.01+ frame reorder
init_get_bits(&s->gb, s->bitstream_buffer, s->bitstream_buffer_size);
}else
init_get_bits(&s->gb, buf, buf_size);
s->bitstream_buffer_size=0;
if (!s->context_initialized) {
if (MPV_common_init(s) < 0) //we need the idct permutaton for reading a custom matrix
return -1;
}
/* let's go :-) */
if (s->h263_msmpeg4) {
ret = msmpeg4_decode_picture_header(s);
} else if (s->h263_pred) {
if(s->avctx->extradata_size && s->picture_number==0){
GetBitContext gb;
init_get_bits(&gb, s->avctx->extradata, s->avctx->extradata_size);
ret = ff_mpeg4_decode_picture_header(s, &gb);
}
ret = ff_mpeg4_decode_picture_header(s, &s->gb);
if(s->flags& CODEC_FLAG_LOW_DELAY)
s->low_delay=1;
s->has_b_frames= !s->low_delay;
} else if (s->h263_intel) {
ret = intel_h263_decode_picture_header(s);
} else {
ret = h263_decode_picture_header(s);
}
avctx->has_b_frames= s->has_b_frames;
if(s->workaround_bugs&FF_BUG_AUTODETECT){
if(s->avctx->fourcc == ff_get_fourcc("XVIX"))
s->workaround_bugs|= FF_BUG_XVID_ILACE;
if(s->avctx->fourcc == ff_get_fourcc("MP4S"))
s->workaround_bugs|= FF_BUG_AC_VLC;
if(s->avctx->fourcc == ff_get_fourcc("M4S2"))
s->workaround_bugs|= FF_BUG_AC_VLC;
if(s->avctx->fourcc == ff_get_fourcc("UMP4")){
s->workaround_bugs|= FF_BUG_UMP4;
s->workaround_bugs|= FF_BUG_AC_VLC;
}
if(s->divx_version){
s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
}
if(s->avctx->fourcc == ff_get_fourcc("XVID") && s->xvid_build==0)
s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
if(s->xvid_build && s->xvid_build<=1)
s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
//printf("padding_bug_score: %d\n", s->padding_bug_score);
#if 0
if(s->divx_version==500)
s->workaround_bugs|= FF_BUG_NO_PADDING;
/* very ugly XVID padding bug detection FIXME/XXX solve this differently
* lets hope this at least works
*/
if( s->resync_marker==0 && s->data_partitioning==0 && s->divx_version==0
&& s->codec_id==CODEC_ID_MPEG4 && s->vo_type==0)
s->workaround_bugs|= FF_BUG_NO_PADDING;
if(s->lavc_build && s->lavc_build<4609) //FIXME not sure about the version num but a 4609 file seems ok
s->workaround_bugs|= FF_BUG_NO_PADDING;
#endif
}
#if 0 // dump bits per frame / qp / complexity
{
static FILE *f=NULL;
if(!f) f=fopen("rate_qp_cplx.txt", "w");
fprintf(f, "%d %d %f\n", buf_size, s->qscale, buf_size*(double)s->qscale);
}
#endif
/* After H263 & mpeg4 header decode we have the height, width,*/
/* and other parameters. So then we could init the picture */
/* FIXME: By the way H263 decoder is evolving it should have */
/* an H263EncContext */
if ( s->width != avctx->width || s->height != avctx->height
|| avctx->aspect_ratio_info != s->aspect_ratio_info
|| avctx->aspected_width != s->aspected_width
|| avctx->aspected_height != s->aspected_height) {
/* H.263 could change picture size any time */
MPV_common_end(s);
s->context_initialized=0;
}
if (!s->context_initialized) {
avctx->width = s->width;
avctx->height = s->height;
avctx->aspect_ratio_info= s->aspect_ratio_info;
if (s->aspect_ratio_info == FF_ASPECT_EXTENDED)
{
avctx->aspected_width = s->aspected_width;
avctx->aspected_height = s->aspected_height;
}
goto retry;
}
if((s->codec_id==CODEC_ID_H263 || s->codec_id==CODEC_ID_H263P))
s->gob_index = ff_h263_get_gob_height(s);
if(ret==FRAME_SKIPED) return get_consumed_bytes(s, buf_size);
/* skip if the header was thrashed */
if (ret < 0){
fprintf(stderr, "header damaged\n");
return -1;
}
/* skip b frames if we dont have reference frames */
if(s->num_available_buffers<2 && s->pict_type==B_TYPE) return get_consumed_bytes(s, buf_size);
/* skip b frames if we are in a hurry */
if(s->hurry_up && s->pict_type==B_TYPE) return get_consumed_bytes(s, buf_size);
if(s->next_p_frame_damaged){
if(s->pict_type==B_TYPE)
return get_consumed_bytes(s, buf_size);
else
s->next_p_frame_damaged=0;
}
if(MPV_frame_start(s, avctx) < 0)
return -1;
#ifdef DEBUG
printf("qscale=%d\n", s->qscale);
#endif
if(s->error_resilience)
memset(s->error_status_table, MV_ERROR|AC_ERROR|DC_ERROR|VP_START|AC_END|DC_END|MV_END, s->mb_num*sizeof(UINT8));
/* decode each macroblock */
s->block_wrap[0]=
s->block_wrap[1]=
s->block_wrap[2]=
s->block_wrap[3]= s->mb_width*2 + 2;
s->block_wrap[4]=
s->block_wrap[5]= s->mb_width + 2;
s->mb_x=0;
s->mb_y=0;
decode_slice(s);
s->error_status_table[0]|= VP_START;
while(s->mb_y<s->mb_height && s->gb.size*8 - get_bits_count(&s->gb)>16){
if(s->msmpeg4_version){
if(s->mb_x!=0 || (s->mb_y%s->slice_height)!=0)
break;
}else{
if(ff_h263_resync(s)<0)
break;
}
if(s->msmpeg4_version!=4 && s->h263_pred)
ff_mpeg4_clean_buffers(s);
decode_slice(s);
s->error_status_table[s->resync_mb_x + s->resync_mb_y*s->mb_width]|= VP_START;
}
if (s->h263_msmpeg4 && s->msmpeg4_version<4 && s->pict_type==I_TYPE)
if(msmpeg4_decode_ext_header(s, buf_size) < 0) return -1;
/* divx 5.01+ bistream reorder stuff */
if(s->codec_id==CODEC_ID_MPEG4 && s->bitstream_buffer_size==0 && s->divx_version>=500){
int current_pos= get_bits_count(&s->gb)>>3;
if( buf_size - current_pos > 5
&& buf_size - current_pos < BITSTREAM_BUFFER_SIZE){
int i;
int startcode_found=0;
for(i=current_pos; i<buf_size-3; i++){
if(buf[i]==0 && buf[i+1]==0 && buf[i+2]==1 && buf[i+3]==0xB6){
startcode_found=1;
break;
}
}
if(startcode_found){
memcpy(s->bitstream_buffer, buf + current_pos, buf_size - current_pos);
s->bitstream_buffer_size= buf_size - current_pos;
}
}
}
if(s->error_resilience){
int error=0, num_end_markers=0;
for(i=0; i<s->mb_num; i++){
int status= s->error_status_table[i];
#if 0
if(i%s->mb_width == 0) printf("\n");
printf("%2X ", status);
#endif
if(status==0) continue;
if(status&(DC_ERROR|AC_ERROR|MV_ERROR))
error=1;
if(status&VP_START){
if(num_end_markers)
error=1;
num_end_markers=3;
}
if(status&AC_END)
num_end_markers--;
if(status&DC_END)
num_end_markers--;
if(status&MV_END)
num_end_markers--;
}
if(num_end_markers || error){
fprintf(stderr, "concealing errors\n");
//printf("type:%d\n", s->pict_type);
ff_error_resilience(s);
}
}
MPV_frame_end(s);
#if 0 //dirty show MVs, we should export the MV tables and write a filter to show them
{
int mb_y;
s->has_b_frames=1;
for(mb_y=0; mb_y<s->mb_height; mb_y++){
int mb_x;
int y= mb_y*16 + 8;
for(mb_x=0; mb_x<s->mb_width; mb_x++){
int x= mb_x*16 + 8;
uint8_t *ptr= s->last_picture[0];
int xy= 1 + mb_x*2 + (mb_y*2 + 1)*(s->mb_width*2 + 2);
int mx= (s->motion_val[xy][0]>>1) + x;
int my= (s->motion_val[xy][1]>>1) + y;
int i;
int max;
if(mx<0) mx=0;
if(my<0) my=0;
if(mx>=s->width) mx= s->width -1;
if(my>=s->height) my= s->height-1;
max= ABS(mx-x);
if(ABS(my-y) > max) max= ABS(my-y);
/* the ugliest linedrawing routine ... */
for(i=0; i<max; i++){
int x1= x + (mx-x)*i/max;
int y1= y + (my-y)*i/max;
ptr[y1*s->linesize + x1]+=100;
}
ptr[y*s->linesize + x]+=100;
s->mbskip_table[mb_x + mb_y*s->mb_width]=0;
}
}
}
#endif
if(s->pict_type==B_TYPE || (!s->has_b_frames)){
pict->data[0] = s->current_picture[0];
pict->data[1] = s->current_picture[1];
pict->data[2] = s->current_picture[2];
} else {
pict->data[0] = s->last_picture[0];
pict->data[1] = s->last_picture[1];
pict->data[2] = s->last_picture[2];
}
pict->linesize[0] = s->linesize;
pict->linesize[1] = s->uvlinesize;
pict->linesize[2] = s->uvlinesize;
avctx->quality = s->qscale;
/* Return the Picture timestamp as the frame number */
/* we substract 1 because it is added on utils.c */
avctx->frame_number = s->picture_number - 1;
/* dont output the last pic after seeking
note we allready added +1 for the current pix in MPV_frame_end(s) */
if(s->num_available_buffers>=2 || (!s->has_b_frames))
*data_size = sizeof(AVPicture);
#ifdef PRINT_FRAME_TIME
printf("%Ld\n", rdtsc()-time);
#endif
return get_consumed_bytes(s, buf_size);
}
AVCodec mpeg4_decoder = {
"mpeg4",
CODEC_TYPE_VIDEO,
CODEC_ID_MPEG4,
sizeof(MpegEncContext),
h263_decode_init,
NULL,
h263_decode_end,
h263_decode_frame,
CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
};
AVCodec h263_decoder = {
"h263",
CODEC_TYPE_VIDEO,
CODEC_ID_H263,
sizeof(MpegEncContext),
h263_decode_init,
NULL,
h263_decode_end,
h263_decode_frame,
CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
};
AVCodec msmpeg4v1_decoder = {
"msmpeg4v1",
CODEC_TYPE_VIDEO,
CODEC_ID_MSMPEG4V1,
sizeof(MpegEncContext),
h263_decode_init,
NULL,
h263_decode_end,
h263_decode_frame,
CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
};
AVCodec msmpeg4v2_decoder = {
"msmpeg4v2",
CODEC_TYPE_VIDEO,
CODEC_ID_MSMPEG4V2,
sizeof(MpegEncContext),
h263_decode_init,
NULL,
h263_decode_end,
h263_decode_frame,
CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
};
AVCodec msmpeg4v3_decoder = {
"msmpeg4",
CODEC_TYPE_VIDEO,
CODEC_ID_MSMPEG4V3,
sizeof(MpegEncContext),
h263_decode_init,
NULL,
h263_decode_end,
h263_decode_frame,
CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
};
AVCodec wmv1_decoder = {
"wmv1",
CODEC_TYPE_VIDEO,
CODEC_ID_WMV1,
sizeof(MpegEncContext),
h263_decode_init,
NULL,
h263_decode_end,
h263_decode_frame,
CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
};
AVCodec wmv2_decoder = {
"wmv2",
CODEC_TYPE_VIDEO,
CODEC_ID_WMV2,
sizeof(MpegEncContext),
h263_decode_init,
NULL,
h263_decode_end,
h263_decode_frame,
CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
};
AVCodec h263i_decoder = {
"h263i",
CODEC_TYPE_VIDEO,
CODEC_ID_H263I,
sizeof(MpegEncContext),
h263_decode_init,
NULL,
h263_decode_end,
h263_decode_frame,
CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
};
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