3 * Copyright (c) 2001 Fabrice Bellard
4 * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
6 * This file is part of Libav.
8 * Libav 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 * Libav 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 Libav; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
28 #include "libavutil/cpu.h"
32 #include "mpegvideo.h"
34 #include "h263_parser.h"
35 #include "mpeg4video_parser.h"
37 #include "vdpau_internal.h"
40 #include "mpeg4video.h"
43 //#define PRINT_FRAME_TIME
45 av_cold int ff_h263_decode_init(AVCodecContext *avctx)
47 MpegEncContext *s = avctx->priv_data;
50 s->out_format = FMT_H263;
52 s->width = avctx->coded_width;
53 s->height = avctx->coded_height;
54 s->workaround_bugs= avctx->workaround_bugs;
57 MPV_decode_defaults(s);
59 s->decode_mb= ff_h263_decode_mb;
61 avctx->pix_fmt= avctx->get_format(avctx, avctx->codec->pix_fmts);
62 s->unrestricted_mv= 1;
64 /* select sub codec */
65 switch(avctx->codec->id) {
67 s->unrestricted_mv= 0;
68 avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;
72 case CODEC_ID_MSMPEG4V1:
76 case CODEC_ID_MSMPEG4V2:
80 case CODEC_ID_MSMPEG4V3:
94 case CODEC_ID_VC1IMAGE:
95 case CODEC_ID_WMV3IMAGE:
98 avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;
108 s->codec_id= avctx->codec->id;
109 avctx->hwaccel= ff_find_hwaccel(avctx->codec->id, avctx->pix_fmt);
111 /* for h263, we allocate the images after having read the header */
112 if (avctx->codec->id != CODEC_ID_H263 && avctx->codec->id != CODEC_ID_MPEG4)
113 if (MPV_common_init(s) < 0)
116 h263_decode_init_vlc(s);
121 av_cold int ff_h263_decode_end(AVCodecContext *avctx)
123 MpegEncContext *s = avctx->priv_data;
130 * Return the number of bytes consumed for building the current frame.
132 static int get_consumed_bytes(MpegEncContext *s, int buf_size){
133 int pos= (get_bits_count(&s->gb)+7)>>3;
135 if(s->divx_packed || s->avctx->hwaccel){
136 //we would have to scan through the whole buf to handle the weird reordering ...
138 }else if(s->flags&CODEC_FLAG_TRUNCATED){
139 pos -= s->parse_context.last_index;
140 if(pos<0) pos=0; // padding is not really read so this might be -1
143 if(pos==0) pos=1; //avoid infinite loops (i doubt that is needed but ...)
144 if(pos+10>buf_size) pos=buf_size; // oops ;)
150 static int decode_slice(MpegEncContext *s){
151 const int part_mask= s->partitioned_frame ? (ER_AC_END|ER_AC_ERROR) : 0x7F;
152 const int mb_size= 16>>s->avctx->lowres;
153 s->last_resync_gb= s->gb;
154 s->first_slice_line= 1;
156 s->resync_mb_x= s->mb_x;
157 s->resync_mb_y= s->mb_y;
159 ff_set_qscale(s, s->qscale);
161 if (s->avctx->hwaccel) {
162 const uint8_t *start= s->gb.buffer + get_bits_count(&s->gb)/8;
163 const uint8_t *end = ff_h263_find_resync_marker(start + 1, s->gb.buffer_end);
164 skip_bits_long(&s->gb, 8*(end - start));
165 return s->avctx->hwaccel->decode_slice(s->avctx, start, end - start);
168 if(s->partitioned_frame){
169 const int qscale= s->qscale;
171 if(CONFIG_MPEG4_DECODER && s->codec_id==CODEC_ID_MPEG4){
172 if(ff_mpeg4_decode_partitions(s) < 0)
176 /* restore variables which were modified */
177 s->first_slice_line=1;
178 s->mb_x= s->resync_mb_x;
179 s->mb_y= s->resync_mb_y;
180 ff_set_qscale(s, qscale);
183 for(; s->mb_y < s->mb_height; s->mb_y++) {
184 /* per-row end of slice checks */
185 if(s->msmpeg4_version){
186 if(s->resync_mb_y + s->slice_height == s->mb_y){
187 ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, ER_MB_END);
193 if(s->msmpeg4_version==1){
199 ff_init_block_index(s);
200 for(; s->mb_x < s->mb_width; s->mb_x++) {
203 ff_update_block_index(s);
205 if(s->resync_mb_x == s->mb_x && s->resync_mb_y+1 == s->mb_y){
206 s->first_slice_line=0;
211 s->mv_dir = MV_DIR_FORWARD;
212 s->mv_type = MV_TYPE_16X16;
213 // s->mb_skipped = 0;
214 //printf("%d %d %06X\n", ret, get_bits_count(&s->gb), show_bits(&s->gb, 24));
215 ret= s->decode_mb(s, s->block);
217 if (s->pict_type!=AV_PICTURE_TYPE_B)
218 ff_h263_update_motion_val(s);
221 const int xy= s->mb_x + s->mb_y*s->mb_stride;
223 MPV_decode_mb(s, s->block);
225 ff_h263_loop_filter(s);
227 //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));
228 ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, ER_MB_END&part_mask);
230 s->padding_bug_score--;
232 if(++s->mb_x >= s->mb_width){
234 ff_draw_horiz_band(s, s->mb_y*mb_size, mb_size);
235 MPV_report_decode_progress(s);
239 }else if(ret==SLICE_NOEND){
240 av_log(s->avctx, AV_LOG_ERROR, "Slice mismatch at MB: %d\n", xy);
241 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);
244 av_log(s->avctx, AV_LOG_ERROR, "Error at MB: %d\n", xy);
245 ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, ER_MB_ERROR&part_mask);
250 MPV_decode_mb(s, s->block);
252 ff_h263_loop_filter(s);
255 ff_draw_horiz_band(s, s->mb_y*mb_size, mb_size);
256 MPV_report_decode_progress(s);
261 assert(s->mb_x==0 && s->mb_y==s->mb_height);
263 if(s->codec_id==CODEC_ID_MPEG4
264 && (s->workaround_bugs&FF_BUG_AUTODETECT)
265 && get_bits_left(&s->gb) >= 48
266 && show_bits(&s->gb, 24)==0x4010
267 && !s->data_partitioning)
268 s->padding_bug_score+=32;
270 /* try to detect the padding bug */
271 if( s->codec_id==CODEC_ID_MPEG4
272 && (s->workaround_bugs&FF_BUG_AUTODETECT)
273 && get_bits_left(&s->gb) >=0
274 && get_bits_left(&s->gb) < 48
275 // && !s->resync_marker
276 && !s->data_partitioning){
278 const int bits_count= get_bits_count(&s->gb);
279 const int bits_left = s->gb.size_in_bits - bits_count;
282 s->padding_bug_score+=16;
283 } else if(bits_left != 1){
284 int v= show_bits(&s->gb, 8);
285 v|= 0x7F >> (7-(bits_count&7));
287 if(v==0x7F && bits_left<=8)
288 s->padding_bug_score--;
289 else if(v==0x7F && ((get_bits_count(&s->gb)+8)&8) && bits_left<=16)
290 s->padding_bug_score+= 4;
292 s->padding_bug_score++;
296 if(s->workaround_bugs&FF_BUG_AUTODETECT){
297 if(s->padding_bug_score > -2 && !s->data_partitioning /*&& (s->divx_version>=0 || !s->resync_marker)*/)
298 s->workaround_bugs |= FF_BUG_NO_PADDING;
300 s->workaround_bugs &= ~FF_BUG_NO_PADDING;
303 // handle formats which don't have unique end markers
304 if(s->msmpeg4_version || (s->workaround_bugs&FF_BUG_NO_PADDING)){ //FIXME perhaps solve this more cleanly
305 int left= get_bits_left(&s->gb);
308 /* no markers in M$ crap */
309 if(s->msmpeg4_version && s->pict_type==AV_PICTURE_TYPE_I)
312 /* buggy padding but the frame should still end approximately at the bitstream end */
313 if((s->workaround_bugs&FF_BUG_NO_PADDING) && (s->err_recognition&AV_EF_BUFFER))
315 else if((s->workaround_bugs&FF_BUG_NO_PADDING))
316 max_extra+= 256*256*256*64;
319 av_log(s->avctx, AV_LOG_ERROR, "discarding %d junk bits at end, next would be %X\n", left, show_bits(&s->gb, 24));
322 av_log(s->avctx, AV_LOG_ERROR, "overreading %d bits\n", -left);
324 ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, ER_MB_END);
329 av_log(s->avctx, AV_LOG_ERROR, "slice end not reached but screenspace end (%d left %06X, score= %d)\n",
330 get_bits_left(&s->gb),
331 show_bits(&s->gb, 24), s->padding_bug_score);
333 ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, ER_MB_END&part_mask);
338 int ff_h263_decode_frame(AVCodecContext *avctx,
339 void *data, int *data_size,
342 const uint8_t *buf = avpkt->data;
343 int buf_size = avpkt->size;
344 MpegEncContext *s = avctx->priv_data;
346 AVFrame *pict = data;
348 #ifdef PRINT_FRAME_TIME
349 uint64_t time= rdtsc();
351 s->flags= avctx->flags;
352 s->flags2= avctx->flags2;
354 /* no supplementary picture */
356 /* special case for last picture */
357 if (s->low_delay==0 && s->next_picture_ptr) {
358 *pict= *(AVFrame*)s->next_picture_ptr;
359 s->next_picture_ptr= NULL;
361 *data_size = sizeof(AVFrame);
367 if(s->flags&CODEC_FLAG_TRUNCATED){
370 if(CONFIG_MPEG4_DECODER && s->codec_id==CODEC_ID_MPEG4){
371 next= ff_mpeg4_find_frame_end(&s->parse_context, buf, buf_size);
372 }else if(CONFIG_H263_DECODER && s->codec_id==CODEC_ID_H263){
373 next= ff_h263_find_frame_end(&s->parse_context, buf, buf_size);
375 av_log(s->avctx, AV_LOG_ERROR, "this codec does not support truncated bitstreams\n");
379 if( ff_combine_frame(&s->parse_context, next, (const uint8_t **)&buf, &buf_size) < 0 )
386 if(s->bitstream_buffer_size && (s->divx_packed || buf_size<20)){ //divx 5.01+/xvid frame reorder
387 init_get_bits(&s->gb, s->bitstream_buffer, s->bitstream_buffer_size*8);
389 init_get_bits(&s->gb, buf, buf_size*8);
390 s->bitstream_buffer_size=0;
392 if (!s->context_initialized) {
393 if (MPV_common_init(s) < 0) //we need the idct permutaton for reading a custom matrix
397 /* We need to set current_picture_ptr before reading the header,
398 * otherwise we cannot store anyting in there */
399 if (s->current_picture_ptr == NULL || s->current_picture_ptr->f.data[0]) {
400 int i= ff_find_unused_picture(s, 0);
403 s->current_picture_ptr= &s->picture[i];
407 if (CONFIG_WMV2_DECODER && s->msmpeg4_version==5) {
408 ret= ff_wmv2_decode_picture_header(s);
409 } else if (CONFIG_MSMPEG4_DECODER && s->msmpeg4_version) {
410 ret = msmpeg4_decode_picture_header(s);
411 } else if (CONFIG_MPEG4_DECODER && s->h263_pred) {
412 if(s->avctx->extradata_size && s->picture_number==0){
415 init_get_bits(&gb, s->avctx->extradata, s->avctx->extradata_size*8);
416 ret = ff_mpeg4_decode_picture_header(s, &gb);
418 ret = ff_mpeg4_decode_picture_header(s, &s->gb);
419 } else if (CONFIG_H263I_DECODER && s->codec_id == CODEC_ID_H263I) {
420 ret = ff_intel_h263_decode_picture_header(s);
421 } else if (CONFIG_FLV_DECODER && s->h263_flv) {
422 ret = ff_flv_decode_picture_header(s);
424 ret = h263_decode_picture_header(s);
427 if(ret==FRAME_SKIPPED) return get_consumed_bytes(s, buf_size);
429 /* skip if the header was thrashed */
431 av_log(s->avctx, AV_LOG_ERROR, "header damaged\n");
435 avctx->has_b_frames= !s->low_delay;
437 if(s->xvid_build==-1 && s->divx_version==-1 && s->lavc_build==-1){
438 if(s->stream_codec_tag == AV_RL32("XVID") ||
439 s->codec_tag == AV_RL32("XVID") || s->codec_tag == AV_RL32("XVIX") ||
440 s->codec_tag == AV_RL32("RMP4") ||
441 s->codec_tag == AV_RL32("SIPP")
445 if(s->codec_tag == AV_RL32("DIVX") && s->vo_type==0 && s->vol_control_parameters==1
446 && s->padding_bug_score > 0 && s->low_delay) // XVID with modified fourcc
451 if(s->xvid_build==-1 && s->divx_version==-1 && s->lavc_build==-1){
452 if(s->codec_tag == AV_RL32("DIVX") && s->vo_type==0 && s->vol_control_parameters==0)
453 s->divx_version= 400; //divx 4
456 if(s->xvid_build>=0 && s->divx_version>=0){
461 if(s->workaround_bugs&FF_BUG_AUTODETECT){
462 if(s->codec_tag == AV_RL32("XVIX"))
463 s->workaround_bugs|= FF_BUG_XVID_ILACE;
465 if(s->codec_tag == AV_RL32("UMP4")){
466 s->workaround_bugs|= FF_BUG_UMP4;
469 if(s->divx_version>=500 && s->divx_build<1814){
470 s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
473 if(s->divx_version>502 && s->divx_build<1814){
474 s->workaround_bugs|= FF_BUG_QPEL_CHROMA2;
477 if(s->xvid_build<=3U)
478 s->padding_bug_score= 256*256*256*64;
480 if(s->xvid_build<=1U)
481 s->workaround_bugs|= FF_BUG_QPEL_CHROMA;
483 if(s->xvid_build<=12U)
484 s->workaround_bugs|= FF_BUG_EDGE;
486 if(s->xvid_build<=32U)
487 s->workaround_bugs|= FF_BUG_DC_CLIP;
489 #define SET_QPEL_FUNC(postfix1, postfix2) \
490 s->dsp.put_ ## postfix1 = ff_put_ ## postfix2;\
491 s->dsp.put_no_rnd_ ## postfix1 = ff_put_no_rnd_ ## postfix2;\
492 s->dsp.avg_ ## postfix1 = ff_avg_ ## postfix2;
494 if(s->lavc_build<4653U)
495 s->workaround_bugs|= FF_BUG_STD_QPEL;
497 if(s->lavc_build<4655U)
498 s->workaround_bugs|= FF_BUG_DIRECT_BLOCKSIZE;
500 if(s->lavc_build<4670U){
501 s->workaround_bugs|= FF_BUG_EDGE;
504 if(s->lavc_build<=4712U)
505 s->workaround_bugs|= FF_BUG_DC_CLIP;
507 if(s->divx_version>=0)
508 s->workaround_bugs|= FF_BUG_DIRECT_BLOCKSIZE;
509 //printf("padding_bug_score: %d\n", s->padding_bug_score);
510 if(s->divx_version==501 && s->divx_build==20020416)
511 s->padding_bug_score= 256*256*256*64;
513 if(s->divx_version<500U){
514 s->workaround_bugs|= FF_BUG_EDGE;
517 if(s->divx_version>=0)
518 s->workaround_bugs|= FF_BUG_HPEL_CHROMA;
520 if(s->divx_version==500)
521 s->padding_bug_score= 256*256*256*64;
523 /* very ugly XVID padding bug detection FIXME/XXX solve this differently
524 * Let us hope this at least works.
526 if( s->resync_marker==0 && s->data_partitioning==0 && s->divx_version==-1
527 && s->codec_id==CODEC_ID_MPEG4 && s->vo_type==0)
528 s->workaround_bugs|= FF_BUG_NO_PADDING;
530 if(s->lavc_build<4609U) //FIXME not sure about the version num but a 4609 file seems ok
531 s->workaround_bugs|= FF_BUG_NO_PADDING;
535 if(s->workaround_bugs& FF_BUG_STD_QPEL){
536 SET_QPEL_FUNC(qpel_pixels_tab[0][ 5], qpel16_mc11_old_c)
537 SET_QPEL_FUNC(qpel_pixels_tab[0][ 7], qpel16_mc31_old_c)
538 SET_QPEL_FUNC(qpel_pixels_tab[0][ 9], qpel16_mc12_old_c)
539 SET_QPEL_FUNC(qpel_pixels_tab[0][11], qpel16_mc32_old_c)
540 SET_QPEL_FUNC(qpel_pixels_tab[0][13], qpel16_mc13_old_c)
541 SET_QPEL_FUNC(qpel_pixels_tab[0][15], qpel16_mc33_old_c)
543 SET_QPEL_FUNC(qpel_pixels_tab[1][ 5], qpel8_mc11_old_c)
544 SET_QPEL_FUNC(qpel_pixels_tab[1][ 7], qpel8_mc31_old_c)
545 SET_QPEL_FUNC(qpel_pixels_tab[1][ 9], qpel8_mc12_old_c)
546 SET_QPEL_FUNC(qpel_pixels_tab[1][11], qpel8_mc32_old_c)
547 SET_QPEL_FUNC(qpel_pixels_tab[1][13], qpel8_mc13_old_c)
548 SET_QPEL_FUNC(qpel_pixels_tab[1][15], qpel8_mc33_old_c)
551 if(avctx->debug & FF_DEBUG_BUGS)
552 av_log(s->avctx, AV_LOG_DEBUG, "bugs: %X lavc_build:%d xvid_build:%d divx_version:%d divx_build:%d %s\n",
553 s->workaround_bugs, s->lavc_build, s->xvid_build, s->divx_version, s->divx_build,
554 s->divx_packed ? "p" : "");
557 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)) {
558 avctx->idct_algo= FF_IDCT_XVIDMMX;
559 avctx->coded_width= 0; // force reinit
560 // dsputil_init(&s->dsp, avctx);
565 /* After H263 & mpeg4 header decode we have the height, width,*/
566 /* and other parameters. So then we could init the picture */
567 /* FIXME: By the way H263 decoder is evolving it should have */
568 /* an H263EncContext */
570 if ( s->width != avctx->coded_width
571 || s->height != avctx->coded_height) {
572 /* H.263 could change picture size any time */
573 ParseContext pc= s->parse_context; //FIXME move these demuxng hack to avformat
574 s->parse_context.buffer=0;
576 s->parse_context= pc;
578 if (!s->context_initialized) {
579 avcodec_set_dimensions(avctx, s->width, s->height);
584 if((s->codec_id==CODEC_ID_H263 || s->codec_id==CODEC_ID_H263P || s->codec_id == CODEC_ID_H263I))
585 s->gob_index = ff_h263_get_gob_height(s);
587 // for skipping the frame
588 s->current_picture.f.pict_type = s->pict_type;
589 s->current_picture.f.key_frame = s->pict_type == AV_PICTURE_TYPE_I;
591 /* skip B-frames if we don't have reference frames */
592 if(s->last_picture_ptr==NULL && (s->pict_type==AV_PICTURE_TYPE_B || s->dropable)) return get_consumed_bytes(s, buf_size);
593 if( (avctx->skip_frame >= AVDISCARD_NONREF && s->pict_type==AV_PICTURE_TYPE_B)
594 || (avctx->skip_frame >= AVDISCARD_NONKEY && s->pict_type!=AV_PICTURE_TYPE_I)
595 || avctx->skip_frame >= AVDISCARD_ALL)
596 return get_consumed_bytes(s, buf_size);
598 if(s->next_p_frame_damaged){
599 if(s->pict_type==AV_PICTURE_TYPE_B)
600 return get_consumed_bytes(s, buf_size);
602 s->next_p_frame_damaged=0;
605 if((s->avctx->flags2 & CODEC_FLAG2_FAST) && s->pict_type==AV_PICTURE_TYPE_B){
606 s->me.qpel_put= s->dsp.put_2tap_qpel_pixels_tab;
607 s->me.qpel_avg= s->dsp.avg_2tap_qpel_pixels_tab;
608 }else if((!s->no_rounding) || s->pict_type==AV_PICTURE_TYPE_B){
609 s->me.qpel_put= s->dsp.put_qpel_pixels_tab;
610 s->me.qpel_avg= s->dsp.avg_qpel_pixels_tab;
612 s->me.qpel_put= s->dsp.put_no_rnd_qpel_pixels_tab;
613 s->me.qpel_avg= s->dsp.avg_qpel_pixels_tab;
616 if(MPV_frame_start(s, avctx) < 0)
619 if (!s->divx_packed) ff_thread_finish_setup(avctx);
621 if (CONFIG_MPEG4_VDPAU_DECODER && (s->avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU)) {
622 ff_vdpau_mpeg4_decode_picture(s, s->gb.buffer, s->gb.buffer_end - s->gb.buffer);
626 if (avctx->hwaccel) {
627 if (avctx->hwaccel->start_frame(avctx, s->gb.buffer, s->gb.buffer_end - s->gb.buffer) < 0)
631 ff_er_frame_start(s);
633 //the second part of the wmv2 header contains the MB skip bits which are stored in current_picture->mb_type
634 //which is not available before MPV_frame_start()
635 if (CONFIG_WMV2_DECODER && s->msmpeg4_version==5){
636 ret = ff_wmv2_decode_secondary_picture_header(s);
637 if(ret<0) return ret;
638 if(ret==1) goto intrax8_decoded;
641 /* decode each macroblock */
645 ret = decode_slice(s);
646 while(s->mb_y<s->mb_height){
647 if(s->msmpeg4_version){
648 if(s->slice_height==0 || s->mb_x!=0 || (s->mb_y%s->slice_height)!=0 || get_bits_count(&s->gb) > s->gb.size_in_bits)
651 int prev_x=s->mb_x, prev_y=s->mb_y;
652 if(ff_h263_resync(s)<0)
654 if (prev_y * s->mb_width + prev_x < s->mb_y * s->mb_width + s->mb_x)
655 s->error_occurred = 1;
658 if(s->msmpeg4_version<4 && s->h263_pred)
659 ff_mpeg4_clean_buffers(s);
661 if (decode_slice(s) < 0) ret = AVERROR_INVALIDDATA;
664 if (s->msmpeg4_version && s->msmpeg4_version<4 && s->pict_type==AV_PICTURE_TYPE_I)
665 if(!CONFIG_MSMPEG4_DECODER || msmpeg4_decode_ext_header(s, buf_size) < 0){
666 s->error_status_table[s->mb_num-1]= ER_MB_ERROR;
669 assert(s->bitstream_buffer_size==0);
671 /* divx 5.01+ bistream reorder stuff */
672 if(s->codec_id==CODEC_ID_MPEG4 && s->divx_packed){
673 int current_pos= get_bits_count(&s->gb)>>3;
674 int startcode_found=0;
676 if(buf_size - current_pos > 5){
678 for(i=current_pos; i<buf_size-3; i++){
679 if(buf[i]==0 && buf[i+1]==0 && buf[i+2]==1 && buf[i+3]==0xB6){
685 if(s->gb.buffer == s->bitstream_buffer && buf_size>7 && s->xvid_build>=0){ //xvid style
692 &s->bitstream_buffer,
693 &s->allocated_bitstream_buffer_size,
694 buf_size - current_pos + FF_INPUT_BUFFER_PADDING_SIZE);
695 if (!s->bitstream_buffer)
696 return AVERROR(ENOMEM);
697 memcpy(s->bitstream_buffer, buf + current_pos, buf_size - current_pos);
698 s->bitstream_buffer_size= buf_size - current_pos;
705 if (avctx->hwaccel) {
706 if (avctx->hwaccel->end_frame(avctx) < 0)
712 assert(s->current_picture.f.pict_type == s->current_picture_ptr->f.pict_type);
713 assert(s->current_picture.f.pict_type == s->pict_type);
714 if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay) {
715 *pict= *(AVFrame*)s->current_picture_ptr;
716 } else if (s->last_picture_ptr != NULL) {
717 *pict= *(AVFrame*)s->last_picture_ptr;
720 if(s->last_picture_ptr || s->low_delay){
721 *data_size = sizeof(AVFrame);
722 ff_print_debug_info(s, pict);
725 #ifdef PRINT_FRAME_TIME
726 av_log(avctx, AV_LOG_DEBUG, "%"PRId64"\n", rdtsc()-time);
729 return (ret && (avctx->err_recognition & AV_EF_EXPLODE))?ret:get_consumed_bytes(s, buf_size);
732 AVCodec ff_h263_decoder = {
734 .type = AVMEDIA_TYPE_VIDEO,
736 .priv_data_size = sizeof(MpegEncContext),
737 .init = ff_h263_decode_init,
738 .close = ff_h263_decode_end,
739 .decode = ff_h263_decode_frame,
740 .capabilities = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
741 .flush= ff_mpeg_flush,
743 .long_name= NULL_IF_CONFIG_SMALL("H.263 / H.263-1996, H.263+ / H.263-1998 / H.263 version 2"),
744 .pix_fmts= ff_hwaccel_pixfmt_list_420,