FFmpeg
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
h263dec.c
Go to the documentation of this file.
1 /*
2  * H.263 decoder
3  * Copyright (c) 2001 Fabrice Bellard
4  * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
5  *
6  * This file is part of FFmpeg.
7  *
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.
12  *
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.
17  *
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
21  */
22 
23 /**
24  * @file
25  * H.263 decoder.
26  */
27 
28 #define UNCHECKED_BITSTREAM_READER 1
29 
30 #include "libavutil/cpu.h"
31 #include "avcodec.h"
32 #include "error_resilience.h"
33 #include "flv.h"
34 #include "h263.h"
35 #include "h263_parser.h"
36 #include "internal.h"
37 #include "mpeg4video.h"
38 #include "mpeg4video_parser.h"
39 #include "mpegvideo.h"
40 #include "msmpeg4.h"
41 #include "vdpau_internal.h"
42 #include "thread.h"
43 
45 {
46  MpegEncContext *s = avctx->priv_data;
47  int ret;
48 
49  s->avctx = avctx;
50  s->out_format = FMT_H263;
51  s->width = avctx->coded_width;
52  s->height = avctx->coded_height;
53  s->workaround_bugs = avctx->workaround_bugs;
54 
55  // set defaults
57  s->quant_precision = 5;
59  s->low_delay = 1;
60  if (avctx->codec->id == AV_CODEC_ID_MSS2)
61  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
62  else
63  avctx->pix_fmt = avctx->get_format(avctx, avctx->codec->pix_fmts);
64  s->unrestricted_mv = 1;
65 
66  /* select sub codec */
67  switch (avctx->codec->id) {
68  case AV_CODEC_ID_H263:
69  case AV_CODEC_ID_H263P:
70  s->unrestricted_mv = 0;
72  break;
73  case AV_CODEC_ID_MPEG4:
74  break;
76  s->h263_pred = 1;
77  s->msmpeg4_version = 1;
78  break;
80  s->h263_pred = 1;
81  s->msmpeg4_version = 2;
82  break;
84  s->h263_pred = 1;
85  s->msmpeg4_version = 3;
86  break;
87  case AV_CODEC_ID_WMV1:
88  s->h263_pred = 1;
89  s->msmpeg4_version = 4;
90  break;
91  case AV_CODEC_ID_WMV2:
92  s->h263_pred = 1;
93  s->msmpeg4_version = 5;
94  break;
95  case AV_CODEC_ID_VC1:
96  case AV_CODEC_ID_WMV3:
99  case AV_CODEC_ID_MSS2:
100  s->h263_pred = 1;
101  s->msmpeg4_version = 6;
103  break;
104  case AV_CODEC_ID_H263I:
105  break;
106  case AV_CODEC_ID_FLV1:
107  s->h263_flv = 1;
108  break;
109  default:
110  return AVERROR(EINVAL);
111  }
112  s->codec_id = avctx->codec->id;
113  avctx->hwaccel = ff_find_hwaccel(avctx->codec->id, avctx->pix_fmt);
114 
115  if (avctx->stream_codec_tag == AV_RL32("l263") && avctx->extradata_size == 56 && avctx->extradata[0] == 1)
116  s->ehc_mode = 1;
117 
118  /* for h263, we allocate the images after having read the header */
119  if (avctx->codec->id != AV_CODEC_ID_H263 &&
120  avctx->codec->id != AV_CODEC_ID_H263P &&
121  avctx->codec->id != AV_CODEC_ID_MPEG4)
122  if ((ret = ff_MPV_common_init(s)) < 0)
123  return ret;
124 
126 
127  return 0;
128 }
129 
131 {
132  MpegEncContext *s = avctx->priv_data;
133 
135  return 0;
136 }
137 
138 /**
139  * Return the number of bytes consumed for building the current frame.
140  */
141 static int get_consumed_bytes(MpegEncContext *s, int buf_size)
142 {
143  int pos = (get_bits_count(&s->gb) + 7) >> 3;
144 
145  if (s->divx_packed || s->avctx->hwaccel) {
146  /* We would have to scan through the whole buf to handle the weird
147  * reordering ... */
148  return buf_size;
149  } else if (s->flags & CODEC_FLAG_TRUNCATED) {
150  pos -= s->parse_context.last_index;
151  // padding is not really read so this might be -1
152  if (pos < 0)
153  pos = 0;
154  return pos;
155  } else {
156  // avoid infinite loops (maybe not needed...)
157  if (pos == 0)
158  pos = 1;
159  // oops ;)
160  if (pos + 10 > buf_size)
161  pos = buf_size;
162 
163  return pos;
164  }
165 }
166 
168 {
169  const int part_mask = s->partitioned_frame ? (ER_AC_END | ER_AC_ERROR) : 0x7F;
170  const int mb_size = 16 >> s->avctx->lowres;
171  int ret;
172 
173  s->last_resync_gb = s->gb;
174  s->first_slice_line = 1;
175  s->resync_mb_x = s->mb_x;
176  s->resync_mb_y = s->mb_y;
177 
178  ff_set_qscale(s, s->qscale);
179 
180  if (s->avctx->hwaccel) {
181  const uint8_t *start = s->gb.buffer + get_bits_count(&s->gb) / 8;
182  ret = s->avctx->hwaccel->decode_slice(s->avctx, start, s->gb.buffer_end - start);
183  // ensure we exit decode loop
184  s->mb_y = s->mb_height;
185  return ret;
186  }
187 
188  if (s->partitioned_frame) {
189  const int qscale = s->qscale;
190 
191  if (CONFIG_MPEG4_DECODER && s->codec_id == AV_CODEC_ID_MPEG4)
192  if ((ret = ff_mpeg4_decode_partitions(s)) < 0)
193  return ret;
194 
195  /* restore variables which were modified */
196  s->first_slice_line = 1;
197  s->mb_x = s->resync_mb_x;
198  s->mb_y = s->resync_mb_y;
199  ff_set_qscale(s, qscale);
200  }
201 
202  for (; s->mb_y < s->mb_height; s->mb_y++) {
203  /* per-row end of slice checks */
204  if (s->msmpeg4_version) {
205  if (s->resync_mb_y + s->slice_height == s->mb_y) {
207  s->mb_x - 1, s->mb_y, ER_MB_END);
208 
209  return 0;
210  }
211  }
212 
213  if (s->msmpeg4_version == 1) {
214  s->last_dc[0] =
215  s->last_dc[1] =
216  s->last_dc[2] = 128;
217  }
218 
220  for (; s->mb_x < s->mb_width; s->mb_x++) {
221  int ret;
222 
224 
225  if (s->resync_mb_x == s->mb_x && s->resync_mb_y + 1 == s->mb_y)
226  s->first_slice_line = 0;
227 
228  /* DCT & quantize */
229 
230  s->mv_dir = MV_DIR_FORWARD;
231  s->mv_type = MV_TYPE_16X16;
232 // s->mb_skipped = 0;
233  av_dlog(s, "%d %d %06X\n",
234  ret, get_bits_count(&s->gb), show_bits(&s->gb, 24));
235  ret = s->decode_mb(s, s->block);
236 
237  if (s->pict_type != AV_PICTURE_TYPE_B)
239 
240  if (ret < 0) {
241  const int xy = s->mb_x + s->mb_y * s->mb_stride;
242  if (ret == SLICE_END) {
243  ff_MPV_decode_mb(s, s->block);
244  if (s->loop_filter)
246 
248  s->mb_x, s->mb_y, ER_MB_END & part_mask);
249 
250  s->padding_bug_score--;
251 
252  if (++s->mb_x >= s->mb_width) {
253  s->mb_x = 0;
254  ff_mpeg_draw_horiz_band(s, s->mb_y * mb_size, mb_size);
256  s->mb_y++;
257  }
258  return 0;
259  } else if (ret == SLICE_NOEND) {
261  "Slice mismatch at MB: %d\n", xy);
263  s->mb_x + 1, s->mb_y,
264  ER_MB_END & part_mask);
265  return AVERROR_INVALIDDATA;
266  }
267  av_log(s->avctx, AV_LOG_ERROR, "Error at MB: %d\n", xy);
269  s->mb_x, s->mb_y, ER_MB_ERROR & part_mask);
270 
271  return AVERROR_INVALIDDATA;
272  }
273 
274  ff_MPV_decode_mb(s, s->block);
275  if (s->loop_filter)
277  }
278 
279  ff_mpeg_draw_horiz_band(s, s->mb_y * mb_size, mb_size);
281 
282  s->mb_x = 0;
283  }
284 
285  av_assert1(s->mb_x == 0 && s->mb_y == s->mb_height);
286 
287  if (s->codec_id == AV_CODEC_ID_MPEG4 &&
289  get_bits_left(&s->gb) >= 48 &&
290  show_bits(&s->gb, 24) == 0x4010 &&
291  !s->data_partitioning)
292  s->padding_bug_score += 32;
293 
294  /* try to detect the padding bug */
295  if (s->codec_id == AV_CODEC_ID_MPEG4 &&
297  get_bits_left(&s->gb) >= 0 &&
298  get_bits_left(&s->gb) < 137 &&
299  // !s->resync_marker &&
300  !s->data_partitioning) {
301  const int bits_count = get_bits_count(&s->gb);
302  const int bits_left = s->gb.size_in_bits - bits_count;
303 
304  if (bits_left == 0) {
305  s->padding_bug_score += 16;
306  } else if (bits_left != 1) {
307  int v = show_bits(&s->gb, 8);
308  v |= 0x7F >> (7 - (bits_count & 7));
309 
310  if (v == 0x7F && bits_left <= 8)
311  s->padding_bug_score--;
312  else if (v == 0x7F && ((get_bits_count(&s->gb) + 8) & 8) &&
313  bits_left <= 16)
314  s->padding_bug_score += 4;
315  else
316  s->padding_bug_score++;
317  }
318  }
319 
321  if (s->padding_bug_score > -2 && !s->data_partitioning
322  /* && (s->divx_version >= 0 || !s->resync_marker) */)
324  else
326  }
327 
328  // handle formats which don't have unique end markers
329  if (s->msmpeg4_version || (s->workaround_bugs & FF_BUG_NO_PADDING)) { // FIXME perhaps solve this more cleanly
330  int left = get_bits_left(&s->gb);
331  int max_extra = 7;
332 
333  /* no markers in M$ crap */
335  max_extra += 17;
336 
337  /* buggy padding but the frame should still end approximately at
338  * the bitstream end */
339  if ((s->workaround_bugs & FF_BUG_NO_PADDING) &&
341  max_extra += 48;
342  else if ((s->workaround_bugs & FF_BUG_NO_PADDING))
343  max_extra += 256 * 256 * 256 * 64;
344 
345  if (left > max_extra)
347  "discarding %d junk bits at end, next would be %X\n",
348  left, show_bits(&s->gb, 24));
349  else if (left < 0)
350  av_log(s->avctx, AV_LOG_ERROR, "overreading %d bits\n", -left);
351  else
353  s->mb_x - 1, s->mb_y, ER_MB_END);
354 
355  return 0;
356  }
357 
359  "slice end not reached but screenspace end (%d left %06X, score= %d)\n",
360  get_bits_left(&s->gb), show_bits(&s->gb, 24), s->padding_bug_score);
361 
362  ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y,
363  ER_MB_END & part_mask);
364 
365  return AVERROR_INVALIDDATA;
366 }
367 
368 int ff_h263_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
369  AVPacket *avpkt)
370 {
371  const uint8_t *buf = avpkt->data;
372  int buf_size = avpkt->size;
373  MpegEncContext *s = avctx->priv_data;
374  int ret;
375  AVFrame *pict = data;
376 
377  s->flags = avctx->flags;
378  s->flags2 = avctx->flags2;
379 
380  /* no supplementary picture */
381  if (buf_size == 0) {
382  /* special case for last picture */
383  if (s->low_delay == 0 && s->next_picture_ptr) {
384  if ((ret = av_frame_ref(pict, &s->next_picture_ptr->f)) < 0)
385  return ret;
386  s->next_picture_ptr = NULL;
387 
388  *got_frame = 1;
389  }
390 
391  return 0;
392  }
393 
394  if (s->flags & CODEC_FLAG_TRUNCATED) {
395  int next;
396 
397  if (CONFIG_MPEG4_DECODER && s->codec_id == AV_CODEC_ID_MPEG4) {
398  next = ff_mpeg4_find_frame_end(&s->parse_context, buf, buf_size);
399  } else if (CONFIG_H263_DECODER && s->codec_id == AV_CODEC_ID_H263) {
400  next = ff_h263_find_frame_end(&s->parse_context, buf, buf_size);
401  } else if (CONFIG_H263P_DECODER && s->codec_id == AV_CODEC_ID_H263P) {
402  next = ff_h263_find_frame_end(&s->parse_context, buf, buf_size);
403  } else {
405  "this codec does not support truncated bitstreams\n");
406  return AVERROR(EINVAL);
407  }
408 
409  if (ff_combine_frame(&s->parse_context, next, (const uint8_t **)&buf,
410  &buf_size) < 0)
411  return buf_size;
412  }
413 
414 retry:
415  if (s->divx_packed && s->bitstream_buffer_size) {
416  int i;
417  for(i=0; i < buf_size-3; i++) {
418  if (buf[i]==0 && buf[i+1]==0 && buf[i+2]==1) {
419  if (buf[i+3]==0xB0) {
420  av_log(s->avctx, AV_LOG_WARNING, "Discarding excessive bitstream in packed xvid\n");
421  s->bitstream_buffer_size = 0;
422  }
423  break;
424  }
425  }
426  }
427 
428  if (s->bitstream_buffer_size && (s->divx_packed || buf_size < 20)) // divx 5.01+/xvid frame reorder
430  else
431  ret = init_get_bits8(&s->gb, buf, buf_size);
432 
433  s->bitstream_buffer_size = 0;
434  if (ret < 0)
435  return ret;
436 
437  if (!s->context_initialized)
438  if ((ret = ff_MPV_common_init(s)) < 0) // we need the idct permutaton for reading a custom matrix
439  return ret;
440 
441  /* We need to set current_picture_ptr before reading the header,
442  * otherwise we cannot store anyting in there */
443  if (s->current_picture_ptr == NULL || s->current_picture_ptr->f.data[0]) {
444  int i = ff_find_unused_picture(s, 0);
445  if (i < 0)
446  return i;
447  s->current_picture_ptr = &s->picture[i];
448  }
449 
450  /* let's go :-) */
451  if (CONFIG_WMV2_DECODER && s->msmpeg4_version == 5) {
453  } else if (CONFIG_MSMPEG4_DECODER && s->msmpeg4_version) {
455  } else if (CONFIG_MPEG4_DECODER && s->h263_pred) {
456  if (s->avctx->extradata_size && s->picture_number == 0) {
457  GetBitContext gb;
458 
459  if (init_get_bits8(&gb, s->avctx->extradata, s->avctx->extradata_size) >= 0 )
460  ret = ff_mpeg4_decode_picture_header(s, &gb);
461  }
462  ret = ff_mpeg4_decode_picture_header(s, &s->gb);
463  } else if (CONFIG_H263I_DECODER && s->codec_id == AV_CODEC_ID_H263I) {
465  } else if (CONFIG_FLV_DECODER && s->h263_flv) {
467  } else {
469  }
470 
471  if (ret < 0 || ret == FRAME_SKIPPED) {
472  if ( s->width != avctx->coded_width
473  || s->height != avctx->coded_height) {
474  av_log(s->avctx, AV_LOG_WARNING, "Reverting picture dimensions change due to header decoding failure\n");
475  s->width = avctx->coded_width;
476  s->height= avctx->coded_height;
477  }
478  }
479  if (ret == FRAME_SKIPPED)
480  return get_consumed_bytes(s, buf_size);
481 
482  /* skip if the header was thrashed */
483  if (ret < 0) {
484  av_log(s->avctx, AV_LOG_ERROR, "header damaged\n");
485  return ret;
486  }
487 
488  avctx->has_b_frames = !s->low_delay;
489 
490  if (s->xvid_build == -1 && s->divx_version == -1 && s->lavc_build == -1) {
491  if (s->stream_codec_tag == AV_RL32("XVID") ||
492  s->codec_tag == AV_RL32("XVID") ||
493  s->codec_tag == AV_RL32("XVIX") ||
494  s->codec_tag == AV_RL32("RMP4") ||
495  s->codec_tag == AV_RL32("ZMP4") ||
496  s->codec_tag == AV_RL32("SIPP"))
497  s->xvid_build = 0;
498 #if 0
499  if (s->codec_tag == AV_RL32("DIVX") && s->vo_type == 0 &&
500  s->vol_control_parameters == 1 &&
501  s->padding_bug_score > 0 && s->low_delay) // XVID with modified fourcc
502  s->xvid_build = 0;
503 #endif
504  }
505 
506  if (s->xvid_build == -1 && s->divx_version == -1 && s->lavc_build == -1)
507  if (s->codec_tag == AV_RL32("DIVX") && s->vo_type == 0 &&
508  s->vol_control_parameters == 0)
509  s->divx_version = 400; // divx 4
510 
511  if (s->xvid_build >= 0 && s->divx_version >= 0) {
512  s->divx_version =
513  s->divx_build = -1;
514  }
515 
517  if (s->codec_tag == AV_RL32("XVIX"))
519 
520  if (s->codec_tag == AV_RL32("UMP4"))
522 
523  if (s->divx_version >= 500 && s->divx_build < 1814)
525 
526  if (s->divx_version > 502 && s->divx_build < 1814)
528 
529  if (s->xvid_build <= 3U)
530  s->padding_bug_score = 256 * 256 * 256 * 64;
531 
532  if (s->xvid_build <= 1U)
534 
535  if (s->xvid_build <= 12U)
537 
538  if (s->xvid_build <= 32U)
540 
541 #define SET_QPEL_FUNC(postfix1, postfix2) \
542  s->dsp.put_ ## postfix1 = ff_put_ ## postfix2; \
543  s->dsp.put_no_rnd_ ## postfix1 = ff_put_no_rnd_ ## postfix2; \
544  s->dsp.avg_ ## postfix1 = ff_avg_ ## postfix2;
545 
546  if (s->lavc_build < 4653U)
548 
549  if (s->lavc_build < 4655U)
551 
552  if (s->lavc_build < 4670U)
554 
555  if (s->lavc_build <= 4712U)
557 
558  if (s->divx_version >= 0)
560  if (s->divx_version == 501 && s->divx_build == 20020416)
561  s->padding_bug_score = 256 * 256 * 256 * 64;
562 
563  if (s->divx_version < 500U)
565 
566  if (s->divx_version >= 0)
568 #if 0
569  if (s->divx_version == 500)
570  s->padding_bug_score = 256 * 256 * 256 * 64;
571 
572  /* very ugly XVID padding bug detection FIXME/XXX solve this differently
573  * Let us hope this at least works. */
574  if (s->resync_marker == 0 && s->data_partitioning == 0 &&
575  s->divx_version == -1 && s->codec_id == AV_CODEC_ID_MPEG4 &&
576  s->vo_type == 0)
578 
579  // FIXME not sure about the version num but a 4609 file seems ok
580  if (s->lavc_build < 4609U)
582 #endif
583  }
584 
585  if (s->workaround_bugs & FF_BUG_STD_QPEL) {
586  SET_QPEL_FUNC(qpel_pixels_tab[0][5], qpel16_mc11_old_c)
587  SET_QPEL_FUNC(qpel_pixels_tab[0][7], qpel16_mc31_old_c)
588  SET_QPEL_FUNC(qpel_pixels_tab[0][9], qpel16_mc12_old_c)
589  SET_QPEL_FUNC(qpel_pixels_tab[0][11], qpel16_mc32_old_c)
590  SET_QPEL_FUNC(qpel_pixels_tab[0][13], qpel16_mc13_old_c)
591  SET_QPEL_FUNC(qpel_pixels_tab[0][15], qpel16_mc33_old_c)
592 
593  SET_QPEL_FUNC(qpel_pixels_tab[1][5], qpel8_mc11_old_c)
594  SET_QPEL_FUNC(qpel_pixels_tab[1][7], qpel8_mc31_old_c)
595  SET_QPEL_FUNC(qpel_pixels_tab[1][9], qpel8_mc12_old_c)
596  SET_QPEL_FUNC(qpel_pixels_tab[1][11], qpel8_mc32_old_c)
597  SET_QPEL_FUNC(qpel_pixels_tab[1][13], qpel8_mc13_old_c)
598  SET_QPEL_FUNC(qpel_pixels_tab[1][15], qpel8_mc33_old_c)
599  }
600 
601  if (avctx->debug & FF_DEBUG_BUGS)
603  "bugs: %X lavc_build:%d xvid_build:%d divx_version:%d divx_build:%d %s\n",
605  s->divx_version, s->divx_build, s->divx_packed ? "p" : "");
606 
607 #if HAVE_MMX
608  if (s->codec_id == AV_CODEC_ID_MPEG4 && s->xvid_build >= 0 &&
609  avctx->idct_algo == FF_IDCT_AUTO &&
611  avctx->idct_algo = FF_IDCT_XVIDMMX;
613  goto retry;
614  }
615 #endif
616 
617  /* After H263 & mpeg4 header decode we have the height, width,
618  * and other parameters. So then we could init the picture.
619  * FIXME: By the way H263 decoder is evolving it should have
620  * an H263EncContext */
621  if (s->width != avctx->coded_width ||
622  s->height != avctx->coded_height ||
623  s->context_reinit) {
624  /* H.263 could change picture size any time */
625  s->context_reinit = 0;
626 
627  avcodec_set_dimensions(avctx, s->width, s->height);
628 
629  if ((ret = ff_MPV_common_frame_size_change(s)))
630  return ret;
631  }
632 
633  if (s->codec_id == AV_CODEC_ID_H263 ||
634  s->codec_id == AV_CODEC_ID_H263P ||
637 
638  // for skipping the frame
641 
642  /* skip B-frames if we don't have reference frames */
643  if (s->last_picture_ptr == NULL &&
644  (s->pict_type == AV_PICTURE_TYPE_B || s->droppable))
645  return get_consumed_bytes(s, buf_size);
646  if ((avctx->skip_frame >= AVDISCARD_NONREF &&
647  s->pict_type == AV_PICTURE_TYPE_B) ||
648  (avctx->skip_frame >= AVDISCARD_NONKEY &&
649  s->pict_type != AV_PICTURE_TYPE_I) ||
650  avctx->skip_frame >= AVDISCARD_ALL)
651  return get_consumed_bytes(s, buf_size);
652 
653  if (s->next_p_frame_damaged) {
654  if (s->pict_type == AV_PICTURE_TYPE_B)
655  return get_consumed_bytes(s, buf_size);
656  else
657  s->next_p_frame_damaged = 0;
658  }
659 
660  if ((!s->no_rounding) || s->pict_type == AV_PICTURE_TYPE_B) {
663  } else {
666  }
667 
668  if ((ret = ff_MPV_frame_start(s, avctx)) < 0)
669  return ret;
670 
671  if (!s->divx_packed && !avctx->hwaccel)
672  ff_thread_finish_setup(avctx);
673 
674  if (CONFIG_MPEG4_VDPAU_DECODER && (s->avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU)) {
676  goto frame_end;
677  }
678 
679  if (avctx->hwaccel)
680  if ((ret = avctx->hwaccel->start_frame(avctx, s->gb.buffer,
681  s->gb.buffer_end - s->gb.buffer)) < 0)
682  return ret;
683 
685 
686  /* the second part of the wmv2 header contains the MB skip bits which
687  * are stored in current_picture->mb_type which is not available before
688  * ff_MPV_frame_start() */
689  if (CONFIG_WMV2_DECODER && s->msmpeg4_version == 5) {
691  if (ret < 0)
692  return ret;
693  if (ret == 1)
694  goto frame_end;
695  }
696 
697  /* decode each macroblock */
698  s->mb_x = 0;
699  s->mb_y = 0;
700 
701  ret = decode_slice(s);
702  while (s->mb_y < s->mb_height) {
703  if (s->msmpeg4_version) {
704  if (s->slice_height == 0 || s->mb_x != 0 ||
705  (s->mb_y % s->slice_height) != 0 || get_bits_left(&s->gb) < 0)
706  break;
707  } else {
708  int prev_x = s->mb_x, prev_y = s->mb_y;
709  if (ff_h263_resync(s) < 0)
710  break;
711  if (prev_y * s->mb_width + prev_x < s->mb_y * s->mb_width + s->mb_x)
712  s->er.error_occurred = 1;
713  }
714 
715  if (s->msmpeg4_version < 4 && s->h263_pred)
717 
718  if (decode_slice(s) < 0)
719  ret = AVERROR_INVALIDDATA;
720  }
721 
722  if (s->msmpeg4_version && s->msmpeg4_version < 4 &&
724  if (!CONFIG_MSMPEG4_DECODER ||
725  ff_msmpeg4_decode_ext_header(s, buf_size) < 0)
727 
729 frame_end:
730  ff_er_frame_end(&s->er);
731 
732  if (avctx->hwaccel)
733  if ((ret = avctx->hwaccel->end_frame(avctx)) < 0)
734  return ret;
735 
736  ff_MPV_frame_end(s);
737 
738  /* divx 5.01+ bitstream reorder stuff */
739  /* Since this clobbers the input buffer and hwaccel codecs still need the
740  * data during hwaccel->end_frame we should not do this any earlier */
741  if (s->codec_id == AV_CODEC_ID_MPEG4 && s->divx_packed) {
742  int current_pos = s->gb.buffer == s->bitstream_buffer ? 0 : (get_bits_count(&s->gb) >> 3);
743  int startcode_found = 0;
744 
745  if (buf_size - current_pos > 7) {
746  int i;
747  for (i = current_pos; i < buf_size - 4; i++)
748  if (buf[i] == 0 &&
749  buf[i + 1] == 0 &&
750  buf[i + 2] == 1 &&
751  buf[i + 3] == 0xB6) {
752  startcode_found = !(buf[i + 4] & 0x40);
753  break;
754  }
755  }
756 
757  if (startcode_found) {
760  buf_size - current_pos +
762  if (!s->bitstream_buffer)
763  return AVERROR(ENOMEM);
764  memcpy(s->bitstream_buffer, buf + current_pos,
765  buf_size - current_pos);
766  s->bitstream_buffer_size = buf_size - current_pos;
767  }
768  }
769 
770  if (!s->divx_packed && avctx->hwaccel)
771  ff_thread_finish_setup(avctx);
772 
775  if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay) {
776  if ((ret = av_frame_ref(pict, &s->current_picture_ptr->f)) < 0)
777  return ret;
780  } else if (s->last_picture_ptr != NULL) {
781  if ((ret = av_frame_ref(pict, &s->last_picture_ptr->f)) < 0)
782  return ret;
785  }
786 
787  if (s->last_picture_ptr || s->low_delay) {
788  if ( pict->format == AV_PIX_FMT_YUV420P
789  && (s->codec_tag == AV_RL32("GEOV") || s->codec_tag == AV_RL32("GEOX"))) {
790  int x, y, p;
792  for (p=0; p<3; p++) {
793  int w = FF_CEIL_RSHIFT(pict-> width, !!p);
794  int h = FF_CEIL_RSHIFT(pict->height, !!p);
795  int linesize = pict->linesize[p];
796  for (y=0; y<(h>>1); y++)
797  for (x=0; x<w; x++)
798  FFSWAP(int,
799  pict->data[p][x + y*linesize],
800  pict->data[p][x + (h-1-y)*linesize]);
801  }
802  }
803  *got_frame = 1;
804  }
805 
806  if (ret && (avctx->err_recognition & AV_EF_EXPLODE))
807  return ret;
808  else
809  return get_consumed_bytes(s, buf_size);
810 }
811 
813 #if CONFIG_VAAPI
815 #endif
816 #if CONFIG_VDPAU
818 #endif
821 };
822 
824  .name = "h263",
825  .long_name = NULL_IF_CONFIG_SMALL("H.263 / H.263-1996, H.263+ / H.263-1998 / H.263 version 2"),
826  .type = AVMEDIA_TYPE_VIDEO,
827  .id = AV_CODEC_ID_H263,
828  .priv_data_size = sizeof(MpegEncContext),
832  .capabilities = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
834  .flush = ff_mpeg_flush,
835  .max_lowres = 3,
837 };
838 
840  .name = "h263p",
841  .long_name = NULL_IF_CONFIG_SMALL("H.263 / H.263-1996, H.263+ / H.263-1998 / H.263 version 2"),
842  .type = AVMEDIA_TYPE_VIDEO,
843  .id = AV_CODEC_ID_H263P,
844  .priv_data_size = sizeof(MpegEncContext),
848  .capabilities = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
850  .flush = ff_mpeg_flush,
851  .max_lowres = 3,
853 };