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"
30 #include "error_resilience.h"
33 #include "h263_parser.h"
35 #include "mpeg4video.h"
36 #include "mpeg4video_parser.h"
37 #include "mpegvideo.h"
41 av_cold int ff_h263_decode_init(AVCodecContext *avctx)
43 MpegEncContext *s = avctx->priv_data;
47 s->out_format = FMT_H263;
48 s->width = avctx->coded_width;
49 s->height = avctx->coded_height;
50 s->workaround_bugs = avctx->workaround_bugs;
53 ff_MPV_decode_defaults(s);
54 s->quant_precision = 5;
55 s->decode_mb = ff_h263_decode_mb;
57 if (avctx->codec->id == AV_CODEC_ID_MSS2)
58 avctx->pix_fmt = AV_PIX_FMT_YUV420P;
60 avctx->pix_fmt = avctx->get_format(avctx, avctx->codec->pix_fmts);
61 s->unrestricted_mv = 1;
63 /* select sub codec */
64 switch (avctx->codec->id) {
65 case AV_CODEC_ID_H263:
66 s->unrestricted_mv = 0;
67 avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;
69 case AV_CODEC_ID_MPEG4:
71 case AV_CODEC_ID_MSMPEG4V1:
73 s->msmpeg4_version = 1;
75 case AV_CODEC_ID_MSMPEG4V2:
77 s->msmpeg4_version = 2;
79 case AV_CODEC_ID_MSMPEG4V3:
81 s->msmpeg4_version = 3;
83 case AV_CODEC_ID_WMV1:
85 s->msmpeg4_version = 4;
87 case AV_CODEC_ID_WMV2:
89 s->msmpeg4_version = 5;
92 case AV_CODEC_ID_WMV3:
93 case AV_CODEC_ID_VC1IMAGE:
94 case AV_CODEC_ID_WMV3IMAGE:
95 case AV_CODEC_ID_MSS2:
97 s->msmpeg4_version = 6;
98 avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;
100 case AV_CODEC_ID_H263I:
102 case AV_CODEC_ID_FLV1:
106 av_log(avctx, AV_LOG_ERROR, "Unsupported codec %d\n",
108 return AVERROR(ENOSYS);
110 s->codec_id = avctx->codec->id;
111 avctx->hwaccel = ff_find_hwaccel(avctx);
113 /* for h263, we allocate the images after having read the header */
114 if (avctx->codec->id != AV_CODEC_ID_H263 &&
115 avctx->codec->id != AV_CODEC_ID_MPEG4)
116 if ((ret = ff_MPV_common_init(s)) < 0)
119 ff_h263dsp_init(&s->h263dsp);
120 ff_h263_decode_init_vlc();
125 av_cold int ff_h263_decode_end(AVCodecContext *avctx)
127 MpegEncContext *s = avctx->priv_data;
129 ff_MPV_common_end(s);
134 * Return the number of bytes consumed for building the current frame.
136 static int get_consumed_bytes(MpegEncContext *s, int buf_size)
138 int pos = (get_bits_count(&s->gb) + 7) >> 3;
140 if (s->divx_packed || s->avctx->hwaccel) {
141 /* We would have to scan through the whole buf to handle the weird
144 } else if (s->flags & CODEC_FLAG_TRUNCATED) {
145 pos -= s->parse_context.last_index;
146 // padding is not really read so this might be -1
151 // avoid infinite loops (maybe not needed...)
155 if (pos + 10 > buf_size)
162 static int decode_slice(MpegEncContext *s)
164 const int part_mask = s->partitioned_frame
165 ? (ER_AC_END | ER_AC_ERROR) : 0x7F;
166 const int mb_size = 16;
169 s->last_resync_gb = s->gb;
170 s->first_slice_line = 1;
171 s->resync_mb_x = s->mb_x;
172 s->resync_mb_y = s->mb_y;
174 ff_set_qscale(s, s->qscale);
176 if (s->avctx->hwaccel) {
177 const uint8_t *start = s->gb.buffer + get_bits_count(&s->gb) / 8;
178 const uint8_t *end = ff_h263_find_resync_marker(start + 1,
180 skip_bits_long(&s->gb, 8 * (end - start));
181 return s->avctx->hwaccel->decode_slice(s->avctx, start, end - start);
184 if (s->partitioned_frame) {
185 const int qscale = s->qscale;
187 if (CONFIG_MPEG4_DECODER && s->codec_id == AV_CODEC_ID_MPEG4)
188 if ((ret = ff_mpeg4_decode_partitions(s->avctx->priv_data)) < 0)
191 /* restore variables which were modified */
192 s->first_slice_line = 1;
193 s->mb_x = s->resync_mb_x;
194 s->mb_y = s->resync_mb_y;
195 ff_set_qscale(s, qscale);
198 for (; s->mb_y < s->mb_height; s->mb_y++) {
199 /* per-row end of slice checks */
200 if (s->msmpeg4_version) {
201 if (s->resync_mb_y + s->slice_height == s->mb_y) {
202 ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
203 s->mb_x - 1, s->mb_y, ER_MB_END);
209 if (s->msmpeg4_version == 1) {
215 ff_init_block_index(s);
216 for (; s->mb_x < s->mb_width; s->mb_x++) {
219 ff_update_block_index(s);
221 if (s->resync_mb_x == s->mb_x && s->resync_mb_y + 1 == s->mb_y)
222 s->first_slice_line = 0;
226 s->mv_dir = MV_DIR_FORWARD;
227 s->mv_type = MV_TYPE_16X16;
228 av_dlog(s, "%d %d %06X\n",
229 ret, get_bits_count(&s->gb), show_bits(&s->gb, 24));
230 ret = s->decode_mb(s, s->block);
232 if (s->pict_type != AV_PICTURE_TYPE_B)
233 ff_h263_update_motion_val(s);
236 const int xy = s->mb_x + s->mb_y * s->mb_stride;
237 if (ret == SLICE_END) {
238 ff_MPV_decode_mb(s, s->block);
240 ff_h263_loop_filter(s);
242 ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
243 s->mb_x, s->mb_y, ER_MB_END & part_mask);
245 s->padding_bug_score--;
247 if (++s->mb_x >= s->mb_width) {
249 ff_mpeg_draw_horiz_band(s, s->mb_y * mb_size, mb_size);
250 ff_MPV_report_decode_progress(s);
254 } else if (ret == SLICE_NOEND) {
255 av_log(s->avctx, AV_LOG_ERROR,
256 "Slice mismatch at MB: %d\n", xy);
257 ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
258 s->mb_x + 1, s->mb_y,
259 ER_MB_END & part_mask);
260 return AVERROR_INVALIDDATA;
262 av_log(s->avctx, AV_LOG_ERROR, "Error at MB: %d\n", xy);
263 ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
264 s->mb_x, s->mb_y, ER_MB_ERROR & part_mask);
266 return AVERROR_INVALIDDATA;
269 ff_MPV_decode_mb(s, s->block);
271 ff_h263_loop_filter(s);
274 ff_mpeg_draw_horiz_band(s, s->mb_y * mb_size, mb_size);
275 ff_MPV_report_decode_progress(s);
280 assert(s->mb_x == 0 && s->mb_y == s->mb_height);
282 if (s->codec_id == AV_CODEC_ID_MPEG4 &&
283 (s->workaround_bugs & FF_BUG_AUTODETECT) &&
284 get_bits_left(&s->gb) >= 48 &&
285 show_bits(&s->gb, 24) == 0x4010 &&
286 !s->data_partitioning)
287 s->padding_bug_score += 32;
289 /* try to detect the padding bug */
290 if (s->codec_id == AV_CODEC_ID_MPEG4 &&
291 (s->workaround_bugs & FF_BUG_AUTODETECT) &&
292 get_bits_left(&s->gb) >= 0 &&
293 get_bits_left(&s->gb) < 48 &&
294 !s->data_partitioning) {
295 const int bits_count = get_bits_count(&s->gb);
296 const int bits_left = s->gb.size_in_bits - bits_count;
298 if (bits_left == 0) {
299 s->padding_bug_score += 16;
300 } else if (bits_left != 1) {
301 int v = show_bits(&s->gb, 8);
302 v |= 0x7F >> (7 - (bits_count & 7));
304 if (v == 0x7F && bits_left <= 8)
305 s->padding_bug_score--;
306 else if (v == 0x7F && ((get_bits_count(&s->gb) + 8) & 8) &&
308 s->padding_bug_score += 4;
310 s->padding_bug_score++;
314 if (s->workaround_bugs & FF_BUG_AUTODETECT) {
315 if (s->padding_bug_score > -2 && !s->data_partitioning)
316 s->workaround_bugs |= FF_BUG_NO_PADDING;
318 s->workaround_bugs &= ~FF_BUG_NO_PADDING;
321 // handle formats which don't have unique end markers
322 if (s->msmpeg4_version || (s->workaround_bugs & FF_BUG_NO_PADDING)) { // FIXME perhaps solve this more cleanly
323 int left = get_bits_left(&s->gb);
326 /* no markers in M$ crap */
327 if (s->msmpeg4_version && s->pict_type == AV_PICTURE_TYPE_I)
330 /* buggy padding but the frame should still end approximately at
331 * the bitstream end */
332 if ((s->workaround_bugs & FF_BUG_NO_PADDING) &&
333 (s->err_recognition & AV_EF_BUFFER))
335 else if ((s->workaround_bugs & FF_BUG_NO_PADDING))
336 max_extra += 256 * 256 * 256 * 64;
338 if (left > max_extra)
339 av_log(s->avctx, AV_LOG_ERROR,
340 "discarding %d junk bits at end, next would be %X\n",
341 left, show_bits(&s->gb, 24));
343 av_log(s->avctx, AV_LOG_ERROR, "overreading %d bits\n", -left);
345 ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
346 s->mb_x - 1, s->mb_y, ER_MB_END);
351 av_log(s->avctx, AV_LOG_ERROR,
352 "slice end not reached but screenspace end (%d left %06X, score= %d)\n",
353 get_bits_left(&s->gb), show_bits(&s->gb, 24), s->padding_bug_score);
355 ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y,
356 ER_MB_END & part_mask);
358 return AVERROR_INVALIDDATA;
361 int ff_h263_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
364 const uint8_t *buf = avpkt->data;
365 int buf_size = avpkt->size;
366 MpegEncContext *s = avctx->priv_data;
368 AVFrame *pict = data;
370 s->flags = avctx->flags;
371 s->flags2 = avctx->flags2;
373 /* no supplementary picture */
375 /* special case for last picture */
376 if (s->low_delay == 0 && s->next_picture_ptr) {
377 if ((ret = av_frame_ref(pict, &s->next_picture_ptr->f)) < 0)
379 s->next_picture_ptr = NULL;
387 if (s->flags & CODEC_FLAG_TRUNCATED) {
390 if (CONFIG_MPEG4_DECODER && s->codec_id == AV_CODEC_ID_MPEG4) {
391 next = ff_mpeg4_find_frame_end(&s->parse_context, buf, buf_size);
392 } else if (CONFIG_H263_DECODER && s->codec_id == AV_CODEC_ID_H263) {
393 next = ff_h263_find_frame_end(&s->parse_context, buf, buf_size);
395 av_log(s->avctx, AV_LOG_ERROR,
396 "this codec does not support truncated bitstreams\n");
397 return AVERROR(ENOSYS);
400 if (ff_combine_frame(&s->parse_context, next, (const uint8_t **)&buf,
405 if (s->bitstream_buffer_size && (s->divx_packed || buf_size < 20)) // divx 5.01+/xvid frame reorder
406 ret = init_get_bits8(&s->gb, s->bitstream_buffer,
407 s->bitstream_buffer_size);
409 ret = init_get_bits8(&s->gb, buf, buf_size);
410 s->bitstream_buffer_size = 0;
415 if (!s->context_initialized)
416 // we need the idct permutaton for reading a custom matrix
417 if ((ret = ff_MPV_common_init(s)) < 0)
420 /* We need to set current_picture_ptr before reading the header,
421 * otherwise we cannot store anyting in there */
422 if (s->current_picture_ptr == NULL || s->current_picture_ptr->f.data[0]) {
423 int i = ff_find_unused_picture(s, 0);
426 s->current_picture_ptr = &s->picture[i];
430 if (CONFIG_WMV2_DECODER && s->msmpeg4_version == 5) {
431 ret = ff_wmv2_decode_picture_header(s);
432 } else if (CONFIG_MSMPEG4_DECODER && s->msmpeg4_version) {
433 ret = ff_msmpeg4_decode_picture_header(s);
434 } else if (CONFIG_MPEG4_DECODER && avctx->codec_id == AV_CODEC_ID_MPEG4) {
435 if (s->avctx->extradata_size && s->picture_number == 0) {
438 ret = init_get_bits8(&gb, s->avctx->extradata,
439 s->avctx->extradata_size);
442 ff_mpeg4_decode_picture_header(avctx->priv_data, &gb);
444 ret = ff_mpeg4_decode_picture_header(avctx->priv_data, &s->gb);
445 } else if (CONFIG_H263I_DECODER && s->codec_id == AV_CODEC_ID_H263I) {
446 ret = ff_intel_h263_decode_picture_header(s);
447 } else if (CONFIG_FLV_DECODER && s->h263_flv) {
448 ret = ff_flv_decode_picture_header(s);
450 ret = ff_h263_decode_picture_header(s);
453 if (ret == FRAME_SKIPPED)
454 return get_consumed_bytes(s, buf_size);
456 /* skip if the header was thrashed */
458 av_log(s->avctx, AV_LOG_ERROR, "header damaged\n");
462 avctx->has_b_frames = !s->low_delay;
464 #define SET_QPEL_FUNC(postfix1, postfix2) \
465 s->dsp.put_ ## postfix1 = ff_put_ ## postfix2; \
466 s->dsp.put_no_rnd_ ## postfix1 = ff_put_no_rnd_ ## postfix2; \
467 s->dsp.avg_ ## postfix1 = ff_avg_ ## postfix2;
469 if (s->workaround_bugs & FF_BUG_STD_QPEL) {
470 SET_QPEL_FUNC(qpel_pixels_tab[0][5], qpel16_mc11_old_c)
471 SET_QPEL_FUNC(qpel_pixels_tab[0][7], qpel16_mc31_old_c)
472 SET_QPEL_FUNC(qpel_pixels_tab[0][9], qpel16_mc12_old_c)
473 SET_QPEL_FUNC(qpel_pixels_tab[0][11], qpel16_mc32_old_c)
474 SET_QPEL_FUNC(qpel_pixels_tab[0][13], qpel16_mc13_old_c)
475 SET_QPEL_FUNC(qpel_pixels_tab[0][15], qpel16_mc33_old_c)
477 SET_QPEL_FUNC(qpel_pixels_tab[1][5], qpel8_mc11_old_c)
478 SET_QPEL_FUNC(qpel_pixels_tab[1][7], qpel8_mc31_old_c)
479 SET_QPEL_FUNC(qpel_pixels_tab[1][9], qpel8_mc12_old_c)
480 SET_QPEL_FUNC(qpel_pixels_tab[1][11], qpel8_mc32_old_c)
481 SET_QPEL_FUNC(qpel_pixels_tab[1][13], qpel8_mc13_old_c)
482 SET_QPEL_FUNC(qpel_pixels_tab[1][15], qpel8_mc33_old_c)
485 /* After H263 & mpeg4 header decode we have the height, width,
486 * and other parameters. So then we could init the picture.
487 * FIXME: By the way H263 decoder is evolving it should have
488 * an H263EncContext */
489 if (s->width != avctx->coded_width ||
490 s->height != avctx->coded_height ||
492 /* H.263 could change picture size any time */
493 s->context_reinit = 0;
495 ret = ff_set_dimensions(avctx, s->width, s->height);
499 if ((ret = ff_MPV_common_frame_size_change(s)))
503 if (s->codec_id == AV_CODEC_ID_H263 ||
504 s->codec_id == AV_CODEC_ID_H263P ||
505 s->codec_id == AV_CODEC_ID_H263I)
506 s->gob_index = ff_h263_get_gob_height(s);
508 // for skipping the frame
509 s->current_picture.f.pict_type = s->pict_type;
510 s->current_picture.f.key_frame = s->pict_type == AV_PICTURE_TYPE_I;
512 /* skip B-frames if we don't have reference frames */
513 if (s->last_picture_ptr == NULL &&
514 (s->pict_type == AV_PICTURE_TYPE_B || s->droppable))
515 return get_consumed_bytes(s, buf_size);
516 if ((avctx->skip_frame >= AVDISCARD_NONREF &&
517 s->pict_type == AV_PICTURE_TYPE_B) ||
518 (avctx->skip_frame >= AVDISCARD_NONKEY &&
519 s->pict_type != AV_PICTURE_TYPE_I) ||
520 avctx->skip_frame >= AVDISCARD_ALL)
521 return get_consumed_bytes(s, buf_size);
523 if (s->next_p_frame_damaged) {
524 if (s->pict_type == AV_PICTURE_TYPE_B)
525 return get_consumed_bytes(s, buf_size);
527 s->next_p_frame_damaged = 0;
530 if ((!s->no_rounding) || s->pict_type == AV_PICTURE_TYPE_B) {
531 s->me.qpel_put = s->dsp.put_qpel_pixels_tab;
532 s->me.qpel_avg = s->dsp.avg_qpel_pixels_tab;
534 s->me.qpel_put = s->dsp.put_no_rnd_qpel_pixels_tab;
535 s->me.qpel_avg = s->dsp.avg_qpel_pixels_tab;
538 if ((ret = ff_MPV_frame_start(s, avctx)) < 0)
541 if (!s->divx_packed && !avctx->hwaccel)
542 ff_thread_finish_setup(avctx);
544 if (avctx->hwaccel) {
545 ret = avctx->hwaccel->start_frame(avctx, s->gb.buffer,
546 s->gb.buffer_end - s->gb.buffer);
551 ff_mpeg_er_frame_start(s);
553 /* the second part of the wmv2 header contains the MB skip bits which
554 * are stored in current_picture->mb_type which is not available before
555 * ff_MPV_frame_start() */
556 if (CONFIG_WMV2_DECODER && s->msmpeg4_version == 5) {
557 ret = ff_wmv2_decode_secondary_picture_header(s);
561 goto intrax8_decoded;
564 /* decode each macroblock */
568 ret = decode_slice(s);
569 while (s->mb_y < s->mb_height) {
570 if (s->msmpeg4_version) {
571 if (s->slice_height == 0 || s->mb_x != 0 ||
572 (s->mb_y % s->slice_height) != 0 || get_bits_left(&s->gb) < 0)
575 int prev_x = s->mb_x, prev_y = s->mb_y;
576 if (ff_h263_resync(s) < 0)
578 if (prev_y * s->mb_width + prev_x < s->mb_y * s->mb_width + s->mb_x)
579 s->er.error_occurred = 1;
582 if (s->msmpeg4_version < 4 && s->h263_pred)
583 ff_mpeg4_clean_buffers(s);
585 if (decode_slice(s) < 0)
586 ret = AVERROR_INVALIDDATA;
589 if (s->msmpeg4_version && s->msmpeg4_version < 4 &&
590 s->pict_type == AV_PICTURE_TYPE_I)
591 if (!CONFIG_MSMPEG4_DECODER ||
592 ff_msmpeg4_decode_ext_header(s, buf_size) < 0)
593 s->er.error_status_table[s->mb_num - 1] = ER_MB_ERROR;
595 assert(s->bitstream_buffer_size == 0);
597 if (CONFIG_MPEG4_DECODER && avctx->codec_id == AV_CODEC_ID_MPEG4)
598 ff_mpeg4_frame_end(avctx, buf, buf_size);
601 ff_er_frame_end(&s->er);
603 if (avctx->hwaccel) {
604 ret = avctx->hwaccel->end_frame(avctx);
611 if (!s->divx_packed && avctx->hwaccel)
612 ff_thread_finish_setup(avctx);
614 assert(s->current_picture.f.pict_type ==
615 s->current_picture_ptr->f.pict_type);
616 assert(s->current_picture.f.pict_type == s->pict_type);
617 if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay) {
618 if ((ret = av_frame_ref(pict, &s->current_picture_ptr->f)) < 0)
620 ff_print_debug_info(s, s->current_picture_ptr);
621 } else if (s->last_picture_ptr != NULL) {
622 if ((ret = av_frame_ref(pict, &s->last_picture_ptr->f)) < 0)
624 ff_print_debug_info(s, s->last_picture_ptr);
627 if (s->last_picture_ptr || s->low_delay)
630 if (ret && (avctx->err_recognition & AV_EF_EXPLODE))
633 return get_consumed_bytes(s, buf_size);
636 const enum AVPixelFormat ff_h263_hwaccel_pixfmt_list_420[] = {
638 AV_PIX_FMT_VAAPI_VLD,
647 AVCodec ff_h263_decoder = {
649 .long_name = NULL_IF_CONFIG_SMALL("H.263 / H.263-1996, H.263+ / H.263-1998 / H.263 version 2"),
650 .type = AVMEDIA_TYPE_VIDEO,
651 .id = AV_CODEC_ID_H263,
652 .priv_data_size = sizeof(MpegEncContext),
653 .init = ff_h263_decode_init,
654 .close = ff_h263_decode_end,
655 .decode = ff_h263_decode_frame,
656 .capabilities = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
657 CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
658 .flush = ff_mpeg_flush,
659 .pix_fmts = ff_h263_hwaccel_pixfmt_list_420,