3 * Copyright (c) 2001 Fabrice Bellard
4 * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
6 * This file is part of FFmpeg.
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
28 #define UNCHECKED_BITSTREAM_READER 1
30 #include "libavutil/cpu.h"
34 #include "mpegvideo.h"
36 #include "h263_parser.h"
37 #include "mpeg4video_parser.h"
39 #include "vdpau_internal.h"
42 #include "mpeg4video.h"
45 //#define PRINT_FRAME_TIME
47 av_cold int ff_h263_decode_init(AVCodecContext *avctx)
49 MpegEncContext *s = avctx->priv_data;
52 s->out_format = FMT_H263;
54 s->width = avctx->coded_width;
55 s->height = avctx->coded_height;
56 s->workaround_bugs= avctx->workaround_bugs;
59 ff_MPV_decode_defaults(s);
61 s->decode_mb= ff_h263_decode_mb;
63 avctx->pix_fmt= avctx->get_format(avctx, avctx->codec->pix_fmts);
64 s->unrestricted_mv= 1;
66 /* select sub codec */
67 switch(avctx->codec->id) {
70 s->unrestricted_mv= 0;
71 avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;
75 case CODEC_ID_MSMPEG4V1:
79 case CODEC_ID_MSMPEG4V2:
83 case CODEC_ID_MSMPEG4V3:
97 case CODEC_ID_VC1IMAGE:
98 case CODEC_ID_WMV3IMAGE:
100 s->msmpeg4_version=6;
101 avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;
111 s->codec_id= avctx->codec->id;
112 avctx->hwaccel= ff_find_hwaccel(avctx->codec->id, avctx->pix_fmt);
114 /* for h263, we allocate the images after having read the header */
115 if (avctx->codec->id != CODEC_ID_H263 && avctx->codec->id != CODEC_ID_H263P && avctx->codec->id != CODEC_ID_MPEG4)
116 if (ff_MPV_common_init(s) < 0)
119 ff_h263_decode_init_vlc(s);
124 av_cold int ff_h263_decode_end(AVCodecContext *avctx)
126 MpegEncContext *s = avctx->priv_data;
128 ff_MPV_common_end(s);
133 * Return the number of bytes consumed for building the current frame.
135 static int get_consumed_bytes(MpegEncContext *s, int buf_size){
136 int pos= (get_bits_count(&s->gb)+7)>>3;
138 if(s->divx_packed || s->avctx->hwaccel){
139 //we would have to scan through the whole buf to handle the weird reordering ...
141 }else if(s->flags&CODEC_FLAG_TRUNCATED){
142 pos -= s->parse_context.last_index;
143 if(pos<0) pos=0; // padding is not really read so this might be -1
146 if(pos==0) pos=1; //avoid infinite loops (i doubt that is needed but ...)
147 if(pos+10>buf_size) pos=buf_size; // oops ;)
153 static int decode_slice(MpegEncContext *s){
154 const int part_mask= s->partitioned_frame ? (ER_AC_END|ER_AC_ERROR) : 0x7F;
155 const int mb_size= 16>>s->avctx->lowres;
156 s->last_resync_gb= s->gb;
157 s->first_slice_line= 1;
159 s->resync_mb_x= s->mb_x;
160 s->resync_mb_y= s->mb_y;
162 ff_set_qscale(s, s->qscale);
164 if (s->avctx->hwaccel) {
165 const uint8_t *start= s->gb.buffer + get_bits_count(&s->gb)/8;
166 const uint8_t *end = ff_h263_find_resync_marker(start + 1, s->gb.buffer_end);
167 skip_bits_long(&s->gb, 8*(end - start));
168 return s->avctx->hwaccel->decode_slice(s->avctx, start, end - start);
171 if(s->partitioned_frame){
172 const int qscale= s->qscale;
174 if(CONFIG_MPEG4_DECODER && s->codec_id==CODEC_ID_MPEG4){
175 if(ff_mpeg4_decode_partitions(s) < 0)
179 /* restore variables which were modified */
180 s->first_slice_line=1;
181 s->mb_x= s->resync_mb_x;
182 s->mb_y= s->resync_mb_y;
183 ff_set_qscale(s, qscale);
186 for(; s->mb_y < s->mb_height; s->mb_y++) {
187 /* per-row end of slice checks */
188 if(s->msmpeg4_version){
189 if(s->resync_mb_y + s->slice_height == s->mb_y){
190 ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, ER_MB_END);
196 if(s->msmpeg4_version==1){
202 ff_init_block_index(s);
203 for(; s->mb_x < s->mb_width; s->mb_x++) {
206 ff_update_block_index(s);
208 if(s->resync_mb_x == s->mb_x && s->resync_mb_y+1 == s->mb_y){
209 s->first_slice_line=0;
214 s->mv_dir = MV_DIR_FORWARD;
215 s->mv_type = MV_TYPE_16X16;
216 // s->mb_skipped = 0;
217 //printf("%d %d %06X\n", ret, get_bits_count(&s->gb), show_bits(&s->gb, 24));
218 ret= s->decode_mb(s, s->block);
220 if (s->pict_type!=AV_PICTURE_TYPE_B)
221 ff_h263_update_motion_val(s);
224 const int xy= s->mb_x + s->mb_y*s->mb_stride;
226 ff_MPV_decode_mb(s, s->block);
228 ff_h263_loop_filter(s);
230 //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));
231 ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, ER_MB_END&part_mask);
233 s->padding_bug_score--;
235 if(++s->mb_x >= s->mb_width){
237 ff_draw_horiz_band(s, s->mb_y*mb_size, mb_size);
238 ff_MPV_report_decode_progress(s);
242 }else if(ret==SLICE_NOEND){
243 av_log(s->avctx, AV_LOG_ERROR, "Slice mismatch at MB: %d\n", xy);
244 ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x+1, s->mb_y, ER_MB_END&part_mask);
247 av_log(s->avctx, AV_LOG_ERROR, "Error at MB: %d\n", xy);
248 ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, ER_MB_ERROR&part_mask);
253 ff_MPV_decode_mb(s, s->block);
255 ff_h263_loop_filter(s);
258 ff_draw_horiz_band(s, s->mb_y*mb_size, mb_size);
259 ff_MPV_report_decode_progress(s);
264 assert(s->mb_x==0 && s->mb_y==s->mb_height);
266 if(s->codec_id==CODEC_ID_MPEG4
267 && (s->workaround_bugs&FF_BUG_AUTODETECT)
268 && get_bits_left(&s->gb) >= 48
269 && show_bits(&s->gb, 24)==0x4010
270 && !s->data_partitioning)
271 s->padding_bug_score+=32;
273 /* try to detect the padding bug */
274 if( s->codec_id==CODEC_ID_MPEG4
275 && (s->workaround_bugs&FF_BUG_AUTODETECT)
276 && get_bits_left(&s->gb) >=0
277 && get_bits_left(&s->gb) < 137
278 // && !s->resync_marker
279 && !s->data_partitioning){
281 const int bits_count= get_bits_count(&s->gb);
282 const int bits_left = s->gb.size_in_bits - bits_count;
285 s->padding_bug_score+=16;
286 } else if(bits_left != 1){
287 int v= show_bits(&s->gb, 8);
288 v|= 0x7F >> (7-(bits_count&7));
290 if(v==0x7F && bits_left<=8)
291 s->padding_bug_score--;
292 else if(v==0x7F && ((get_bits_count(&s->gb)+8)&8) && bits_left<=16)
293 s->padding_bug_score+= 4;
295 s->padding_bug_score++;
299 if(s->workaround_bugs&FF_BUG_AUTODETECT){
300 if(s->padding_bug_score > -2 && !s->data_partitioning /*&& (s->divx_version>=0 || !s->resync_marker)*/)
301 s->workaround_bugs |= FF_BUG_NO_PADDING;
303 s->workaround_bugs &= ~FF_BUG_NO_PADDING;
306 // handle formats which don't have unique end markers
307 if(s->msmpeg4_version || (s->workaround_bugs&FF_BUG_NO_PADDING)){ //FIXME perhaps solve this more cleanly
308 int left= get_bits_left(&s->gb);
311 /* no markers in M$ crap */
312 if(s->msmpeg4_version && s->pict_type==AV_PICTURE_TYPE_I)
315 /* buggy padding but the frame should still end approximately at the bitstream end */
316 if((s->workaround_bugs&FF_BUG_NO_PADDING) && (s->err_recognition&(AV_EF_BUFFER|AV_EF_AGGRESSIVE)))
318 else if((s->workaround_bugs&FF_BUG_NO_PADDING))
319 max_extra+= 256*256*256*64;
322 av_log(s->avctx, AV_LOG_ERROR, "discarding %d junk bits at end, next would be %X\n", left, show_bits(&s->gb, 24));
325 av_log(s->avctx, AV_LOG_ERROR, "overreading %d bits\n", -left);
327 ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, ER_MB_END);
332 av_log(s->avctx, AV_LOG_ERROR, "slice end not reached but screenspace end (%d left %06X, score= %d)\n",
333 get_bits_left(&s->gb),
334 show_bits(&s->gb, 24), s->padding_bug_score);
336 ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, ER_MB_END&part_mask);
341 int ff_h263_decode_frame(AVCodecContext *avctx,
342 void *data, int *data_size,
345 const uint8_t *buf = avpkt->data;
346 int buf_size = avpkt->size;
347 MpegEncContext *s = avctx->priv_data;
349 AVFrame *pict = data;
351 #ifdef PRINT_FRAME_TIME
352 uint64_t time= rdtsc();
354 s->flags= avctx->flags;
355 s->flags2= avctx->flags2;
357 /* no supplementary picture */
359 /* special case for last picture */
360 if (s->low_delay==0 && s->next_picture_ptr) {
361 *pict = s->next_picture_ptr->f;
362 s->next_picture_ptr= NULL;
364 *data_size = sizeof(AVFrame);
370 if(s->flags&CODEC_FLAG_TRUNCATED){
373 if(CONFIG_MPEG4_DECODER && s->codec_id==CODEC_ID_MPEG4){
374 next= ff_mpeg4_find_frame_end(&s->parse_context, buf, buf_size);
375 }else if(CONFIG_H263_DECODER && s->codec_id==CODEC_ID_H263){
376 next= ff_h263_find_frame_end(&s->parse_context, buf, buf_size);
377 }else if(CONFIG_H263P_DECODER && s->codec_id==CODEC_ID_H263P){
378 next= ff_h263_find_frame_end(&s->parse_context, buf, buf_size);
380 av_log(s->avctx, AV_LOG_ERROR, "this codec does not support truncated bitstreams\n");
384 if( ff_combine_frame(&s->parse_context, next, (const uint8_t **)&buf, &buf_size) < 0 )
390 if(s->divx_packed && s->bitstream_buffer_size){
392 for(i=0; i<buf_size-3; i++){
393 if(buf[i]==0 && buf[i+1]==0 && buf[i+2]==1){
395 av_log(s->avctx, AV_LOG_WARNING, "Discarding excessive bitstream in packed xvid\n");
396 s->bitstream_buffer_size=0;
403 if(s->bitstream_buffer_size && (s->divx_packed || buf_size<20)){ //divx 5.01+/xvid frame reorder
404 init_get_bits(&s->gb, s->bitstream_buffer, s->bitstream_buffer_size*8);
406 init_get_bits(&s->gb, buf, buf_size*8);
407 s->bitstream_buffer_size=0;
409 if (!s->context_initialized) {
410 if (ff_MPV_common_init(s) < 0) //we need the idct permutaton for reading a custom matrix
414 /* We need to set current_picture_ptr before reading the header,
415 * otherwise we cannot store anyting in there */
416 if (s->current_picture_ptr == NULL || s->current_picture_ptr->f.data[0]) {
417 int i= ff_find_unused_picture(s, 0);
420 s->current_picture_ptr= &s->picture[i];
424 if (CONFIG_WMV2_DECODER && s->msmpeg4_version==5) {
425 ret= ff_wmv2_decode_picture_header(s);
426 } else if (CONFIG_MSMPEG4_DECODER && s->msmpeg4_version) {
427 ret = ff_msmpeg4_decode_picture_header(s);
428 } else if (CONFIG_MPEG4_DECODER && s->h263_pred) {
429 if(s->avctx->extradata_size && s->picture_number==0){
432 init_get_bits(&gb, s->avctx->extradata, s->avctx->extradata_size*8);
433 ret = ff_mpeg4_decode_picture_header(s, &gb);
435 ret = ff_mpeg4_decode_picture_header(s, &s->gb);
436 } else if (CONFIG_H263I_DECODER && s->codec_id == CODEC_ID_H263I) {
437 ret = ff_intel_h263_decode_picture_header(s);
438 } else if (CONFIG_FLV_DECODER && s->h263_flv) {
439 ret = ff_flv_decode_picture_header(s);
441 ret = ff_h263_decode_picture_header(s);
444 if (ret < 0 || ret==FRAME_SKIPPED) {
445 if ( s->width != avctx->coded_width
446 || s->height != avctx->coded_height) {
447 av_log(s->avctx, AV_LOG_WARNING, "Reverting picture dimensions change due to header decoding failure\n");
448 s->width = avctx->coded_width;
449 s->height= avctx->coded_height;
452 if(ret==FRAME_SKIPPED) return get_consumed_bytes(s, buf_size);
454 /* skip if the header was thrashed */
456 av_log(s->avctx, AV_LOG_ERROR, "header damaged\n");
458 } else if ((s->width != avctx->coded_width ||
459 s->height != avctx->coded_height ||
460 (s->width + 15) >> 4 != s->mb_width ||
461 (s->height + 15) >> 4 != s->mb_height) &&
462 (HAVE_THREADS && (s->avctx->active_thread_type & FF_THREAD_FRAME))) {
463 av_log_missing_feature(s->avctx, "Width/height/bit depth/chroma idc changing with threads is", 0);
464 s->width = avctx->coded_width;
465 s->height= avctx->coded_height;
466 return AVERROR_PATCHWELCOME; // width / height changed during parallelized decoding
469 avctx->has_b_frames= !s->low_delay;
471 if(s->xvid_build==-1 && s->divx_version==-1 && s->lavc_build==-1){
472 if(s->stream_codec_tag == AV_RL32("XVID") ||
473 s->codec_tag == AV_RL32("XVID") || s->codec_tag == AV_RL32("XVIX") ||
474 s->codec_tag == AV_RL32("RMP4") ||
475 s->codec_tag == AV_RL32("SIPP")
479 if(s->codec_tag == AV_RL32("DIVX") && s->vo_type==0 && s->vol_control_parameters==1
480 && s->padding_bug_score > 0 && s->low_delay) // XVID with modified fourcc
485 if(s->xvid_build==-1 && s->divx_version==-1 && s->lavc_build==-1){
486 if(s->codec_tag == AV_RL32("DIVX") && s->vo_type==0 && s->vol_control_parameters==0)
487 s->divx_version= 400; //divx 4
490 if(s->xvid_build>=0 && s->divx_version>=0){
495 if(s->workaround_bugs&FF_BUG_AUTODETECT){
496 if(s->codec_tag == AV_RL32("XVIX"))
497 s->workaround_bugs|= FF_BUG_XVID_ILACE;
499 if(s->codec_tag == AV_RL32("UMP4")){
500 s->workaround_bugs|= FF_BUG_UMP4;
503 if(s->divx_version>=500 && s->divx_build<1814){
504 s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
507 if(s->divx_version>502 && s->divx_build<1814){
508 s->workaround_bugs|= FF_BUG_QPEL_CHROMA2;
511 if(s->xvid_build<=3U)
512 s->padding_bug_score= 256*256*256*64;
514 if(s->xvid_build<=1U)
515 s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
517 if(s->xvid_build<=12U)
518 s->workaround_bugs|= FF_BUG_EDGE;
520 if(s->xvid_build<=32U)
521 s->workaround_bugs|= FF_BUG_DC_CLIP;
523 #define SET_QPEL_FUNC(postfix1, postfix2) \
524 s->dsp.put_ ## postfix1 = ff_put_ ## postfix2;\
525 s->dsp.put_no_rnd_ ## postfix1 = ff_put_no_rnd_ ## postfix2;\
526 s->dsp.avg_ ## postfix1 = ff_avg_ ## postfix2;
528 if(s->lavc_build<4653U)
529 s->workaround_bugs|= FF_BUG_STD_QPEL;
531 if(s->lavc_build<4655U)
532 s->workaround_bugs|= FF_BUG_DIRECT_BLOCKSIZE;
534 if(s->lavc_build<4670U){
535 s->workaround_bugs|= FF_BUG_EDGE;
538 if(s->lavc_build<=4712U)
539 s->workaround_bugs|= FF_BUG_DC_CLIP;
541 if(s->divx_version>=0)
542 s->workaround_bugs|= FF_BUG_DIRECT_BLOCKSIZE;
543 //printf("padding_bug_score: %d\n", s->padding_bug_score);
544 if(s->divx_version==501 && s->divx_build==20020416)
545 s->padding_bug_score= 256*256*256*64;
547 if(s->divx_version<500U){
548 s->workaround_bugs|= FF_BUG_EDGE;
551 if(s->divx_version>=0)
552 s->workaround_bugs|= FF_BUG_HPEL_CHROMA;
554 if(s->divx_version==500)
555 s->padding_bug_score= 256*256*256*64;
557 /* very ugly XVID padding bug detection FIXME/XXX solve this differently
558 * Let us hope this at least works.
560 if( s->resync_marker==0 && s->data_partitioning==0 && s->divx_version==-1
561 && s->codec_id==CODEC_ID_MPEG4 && s->vo_type==0)
562 s->workaround_bugs|= FF_BUG_NO_PADDING;
564 if(s->lavc_build<4609U) //FIXME not sure about the version num but a 4609 file seems ok
565 s->workaround_bugs|= FF_BUG_NO_PADDING;
569 if(s->workaround_bugs& FF_BUG_STD_QPEL){
570 SET_QPEL_FUNC(qpel_pixels_tab[0][ 5], qpel16_mc11_old_c)
571 SET_QPEL_FUNC(qpel_pixels_tab[0][ 7], qpel16_mc31_old_c)
572 SET_QPEL_FUNC(qpel_pixels_tab[0][ 9], qpel16_mc12_old_c)
573 SET_QPEL_FUNC(qpel_pixels_tab[0][11], qpel16_mc32_old_c)
574 SET_QPEL_FUNC(qpel_pixels_tab[0][13], qpel16_mc13_old_c)
575 SET_QPEL_FUNC(qpel_pixels_tab[0][15], qpel16_mc33_old_c)
577 SET_QPEL_FUNC(qpel_pixels_tab[1][ 5], qpel8_mc11_old_c)
578 SET_QPEL_FUNC(qpel_pixels_tab[1][ 7], qpel8_mc31_old_c)
579 SET_QPEL_FUNC(qpel_pixels_tab[1][ 9], qpel8_mc12_old_c)
580 SET_QPEL_FUNC(qpel_pixels_tab[1][11], qpel8_mc32_old_c)
581 SET_QPEL_FUNC(qpel_pixels_tab[1][13], qpel8_mc13_old_c)
582 SET_QPEL_FUNC(qpel_pixels_tab[1][15], qpel8_mc33_old_c)
585 if(avctx->debug & FF_DEBUG_BUGS)
586 av_log(s->avctx, AV_LOG_DEBUG, "bugs: %X lavc_build:%d xvid_build:%d divx_version:%d divx_build:%d %s\n",
587 s->workaround_bugs, s->lavc_build, s->xvid_build, s->divx_version, s->divx_build,
588 s->divx_packed ? "p" : "");
591 if (s->codec_id == CODEC_ID_MPEG4 && s->xvid_build>=0 && avctx->idct_algo == FF_IDCT_AUTO && (av_get_cpu_flags() & AV_CPU_FLAG_MMX)) {
592 avctx->idct_algo= FF_IDCT_XVIDMMX;
593 ff_dct_common_init(s);
597 /* After H263 & mpeg4 header decode we have the height, width,*/
598 /* and other parameters. So then we could init the picture */
599 /* FIXME: By the way H263 decoder is evolving it should have */
600 /* an H263EncContext */
602 if ( s->width != avctx->coded_width
603 || s->height != avctx->coded_height) {
604 /* H.263 could change picture size any time */
605 ParseContext pc= s->parse_context; //FIXME move these demuxng hack to avformat
607 s->parse_context.buffer=0;
608 ff_MPV_common_end(s);
609 s->parse_context= pc;
611 if (!s->context_initialized) {
612 avcodec_set_dimensions(avctx, s->width, s->height);
617 if((s->codec_id==CODEC_ID_H263 || s->codec_id==CODEC_ID_H263P || s->codec_id == CODEC_ID_H263I))
618 s->gob_index = ff_h263_get_gob_height(s);
620 // for skipping the frame
621 s->current_picture.f.pict_type = s->pict_type;
622 s->current_picture.f.key_frame = s->pict_type == AV_PICTURE_TYPE_I;
624 /* skip B-frames if we don't have reference frames */
625 if(s->last_picture_ptr==NULL && (s->pict_type==AV_PICTURE_TYPE_B || s->dropable)) return get_consumed_bytes(s, buf_size);
626 if( (avctx->skip_frame >= AVDISCARD_NONREF && s->pict_type==AV_PICTURE_TYPE_B)
627 || (avctx->skip_frame >= AVDISCARD_NONKEY && s->pict_type!=AV_PICTURE_TYPE_I)
628 || avctx->skip_frame >= AVDISCARD_ALL)
629 return get_consumed_bytes(s, buf_size);
631 if(s->next_p_frame_damaged){
632 if(s->pict_type==AV_PICTURE_TYPE_B)
633 return get_consumed_bytes(s, buf_size);
635 s->next_p_frame_damaged=0;
638 if((s->avctx->flags2 & CODEC_FLAG2_FAST) && s->pict_type==AV_PICTURE_TYPE_B){
639 s->me.qpel_put= s->dsp.put_2tap_qpel_pixels_tab;
640 s->me.qpel_avg= s->dsp.avg_2tap_qpel_pixels_tab;
641 }else if((!s->no_rounding) || s->pict_type==AV_PICTURE_TYPE_B){
642 s->me.qpel_put= s->dsp.put_qpel_pixels_tab;
643 s->me.qpel_avg= s->dsp.avg_qpel_pixels_tab;
645 s->me.qpel_put= s->dsp.put_no_rnd_qpel_pixels_tab;
646 s->me.qpel_avg= s->dsp.avg_qpel_pixels_tab;
649 if(ff_MPV_frame_start(s, avctx) < 0)
652 if (!s->divx_packed) ff_thread_finish_setup(avctx);
654 if (CONFIG_MPEG4_VDPAU_DECODER && (s->avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU)) {
655 ff_vdpau_mpeg4_decode_picture(s, s->gb.buffer, s->gb.buffer_end - s->gb.buffer);
659 if (avctx->hwaccel) {
660 if (avctx->hwaccel->start_frame(avctx, s->gb.buffer, s->gb.buffer_end - s->gb.buffer) < 0)
664 ff_er_frame_start(s);
666 //the second part of the wmv2 header contains the MB skip bits which are stored in current_picture->mb_type
667 //which is not available before ff_MPV_frame_start()
668 if (CONFIG_WMV2_DECODER && s->msmpeg4_version==5){
669 ret = ff_wmv2_decode_secondary_picture_header(s);
670 if(ret<0) return ret;
671 if(ret==1) goto intrax8_decoded;
674 /* decode each macroblock */
678 ret = decode_slice(s);
679 while(s->mb_y<s->mb_height){
680 if(s->msmpeg4_version){
681 if(s->slice_height==0 || s->mb_x!=0 || (s->mb_y%s->slice_height)!=0 || get_bits_left(&s->gb)<0)
684 int prev_x=s->mb_x, prev_y=s->mb_y;
685 if(ff_h263_resync(s)<0)
687 if (prev_y * s->mb_width + prev_x < s->mb_y * s->mb_width + s->mb_x)
688 s->error_occurred = 1;
691 if(s->msmpeg4_version<4 && s->h263_pred)
692 ff_mpeg4_clean_buffers(s);
694 if (decode_slice(s) < 0) ret = AVERROR_INVALIDDATA;
697 if (s->msmpeg4_version && s->msmpeg4_version<4 && s->pict_type==AV_PICTURE_TYPE_I)
698 if(!CONFIG_MSMPEG4_DECODER || ff_msmpeg4_decode_ext_header(s, buf_size) < 0){
699 s->error_status_table[s->mb_num-1]= ER_MB_ERROR;
702 assert(s->bitstream_buffer_size==0);
704 /* divx 5.01+ bistream reorder stuff */
705 if(s->codec_id==CODEC_ID_MPEG4 && s->divx_packed){
706 int current_pos= s->gb.buffer == s->bitstream_buffer ? 0 : (get_bits_count(&s->gb)>>3);
707 int startcode_found=0;
709 if(buf_size - current_pos > 7){
711 for(i=current_pos; i<buf_size-4; i++){
712 if(buf[i]==0 && buf[i+1]==0 && buf[i+2]==1 && buf[i+3]==0xB6){
713 startcode_found=!(buf[i+4]&0x40);
721 &s->bitstream_buffer,
722 &s->allocated_bitstream_buffer_size,
723 buf_size - current_pos + FF_INPUT_BUFFER_PADDING_SIZE);
724 if (!s->bitstream_buffer)
725 return AVERROR(ENOMEM);
726 memcpy(s->bitstream_buffer, buf + current_pos, buf_size - current_pos);
727 s->bitstream_buffer_size= buf_size - current_pos;
734 if (avctx->hwaccel) {
735 if (avctx->hwaccel->end_frame(avctx) < 0)
741 assert(s->current_picture.f.pict_type == s->current_picture_ptr->f.pict_type);
742 assert(s->current_picture.f.pict_type == s->pict_type);
743 if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay) {
744 *pict = s->current_picture_ptr->f;
745 } else if (s->last_picture_ptr != NULL) {
746 *pict = s->last_picture_ptr->f;
749 if(s->last_picture_ptr || s->low_delay){
750 *data_size = sizeof(AVFrame);
751 ff_print_debug_info(s, pict);
754 #ifdef PRINT_FRAME_TIME
755 av_log(avctx, AV_LOG_DEBUG, "%"PRId64"\n", rdtsc()-time);
758 return (ret && (avctx->err_recognition & AV_EF_EXPLODE))?ret:get_consumed_bytes(s, buf_size);
761 AVCodec ff_h263_decoder = {
763 .type = AVMEDIA_TYPE_VIDEO,
765 .priv_data_size = sizeof(MpegEncContext),
766 .init = ff_h263_decode_init,
767 .close = ff_h263_decode_end,
768 .decode = ff_h263_decode_frame,
769 .capabilities = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
770 CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
771 .flush = ff_mpeg_flush,
773 .long_name = NULL_IF_CONFIG_SMALL("H.263 / H.263-1996, H.263+ / H.263-1998 / H.263 version 2"),
774 .pix_fmts = ff_hwaccel_pixfmt_list_420,
777 AVCodec ff_h263p_decoder = {
779 .type = AVMEDIA_TYPE_VIDEO,
780 .id = CODEC_ID_H263P,
781 .priv_data_size = sizeof(MpegEncContext),
782 .init = ff_h263_decode_init,
783 .close = ff_h263_decode_end,
784 .decode = ff_h263_decode_frame,
785 .capabilities = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
786 CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
787 .flush = ff_mpeg_flush,
789 .long_name = NULL_IF_CONFIG_SMALL("H.263 / H.263-1996, H.263+ / H.263-1998 / H.263 version 2"),
790 .pix_fmts = ff_hwaccel_pixfmt_list_420,