forked from FFmpeg/FFmpeg
-
Notifications
You must be signed in to change notification settings - Fork 0
/
h264_parser.c
712 lines (635 loc) · 25.4 KB
/
h264_parser.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
/*
* H.26L/H.264/AVC/JVT/14496-10/... parser
* Copyright (c) 2003 Michael Niedermayer <[email protected]>
*
* This file is part of FFmpeg.
*
* FFmpeg 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 2.1 of the License, or (at your option) any later version.
*
* FFmpeg 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 FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* H.264 / AVC / MPEG-4 part10 parser.
* @author Michael Niedermayer <[email protected]>
*/
#define UNCHECKED_BITSTREAM_READER 1
#include <assert.h>
#include <stdint.h>
#include "libavutil/avutil.h"
#include "libavutil/error.h"
#include "libavutil/log.h"
#include "libavutil/mem.h"
#include "libavutil/pixfmt.h"
#include "avcodec.h"
#include "get_bits.h"
#include "golomb.h"
#include "h264.h"
#include "h264_sei.h"
#include "h264_ps.h"
#include "h264data.h"
#include "internal.h"
#include "mpegutils.h"
#include "parser.h"
typedef struct H264ParseContext {
ParseContext pc;
H264ParamSets ps;
H264DSPContext h264dsp;
H264POCContext poc;
H264SEIContext sei;
int is_avc;
int nal_length_size;
int got_first;
int picture_structure;
uint8_t parse_history[6];
int parse_history_count;
int parse_last_mb;
int64_t reference_dts;
int last_frame_num, last_picture_structure;
} H264ParseContext;
static int h264_find_frame_end(H264ParseContext *p, const uint8_t *buf,
int buf_size, void *logctx)
{
int i, j;
uint32_t state;
ParseContext *pc = &p->pc;
int next_avc = p->is_avc ? 0 : buf_size;
// mb_addr= pc->mb_addr - 1;
state = pc->state;
if (state > 13)
state = 7;
if (p->is_avc && !p->nal_length_size)
av_log(logctx, AV_LOG_ERROR, "AVC-parser: nal length size invalid\n");
for (i = 0; i < buf_size; i++) {
if (i >= next_avc) {
int nalsize = 0;
i = next_avc;
for (j = 0; j < p->nal_length_size; j++)
nalsize = (nalsize << 8) | buf[i++];
if (nalsize <= 0 || nalsize > buf_size - i) {
av_log(logctx, AV_LOG_ERROR, "AVC-parser: nal size %d remaining %d\n", nalsize, buf_size - i);
return buf_size;
}
next_avc = i + nalsize;
state = 5;
}
if (state == 7) {
i += p->h264dsp.startcode_find_candidate(buf + i, next_avc - i);
if (i < next_avc)
state = 2;
} else if (state <= 2) {
if (buf[i] == 1)
state ^= 5; // 2->7, 1->4, 0->5
else if (buf[i])
state = 7;
else
state >>= 1; // 2->1, 1->0, 0->0
} else if (state <= 5) {
int nalu_type = buf[i] & 0x1F;
if (nalu_type == H264_NAL_SEI || nalu_type == H264_NAL_SPS ||
nalu_type == H264_NAL_PPS || nalu_type == H264_NAL_AUD) {
if (pc->frame_start_found) {
i++;
goto found;
}
} else if (nalu_type == H264_NAL_SLICE || nalu_type == H264_NAL_DPA ||
nalu_type == H264_NAL_IDR_SLICE) {
state += 8;
continue;
}
state = 7;
} else {
unsigned int mb, last_mb = p->parse_last_mb;
GetBitContext gb;
p->parse_history[p->parse_history_count++] = buf[i];
init_get_bits(&gb, p->parse_history, 8*p->parse_history_count);
mb= get_ue_golomb_long(&gb);
if (get_bits_left(&gb) > 0 || p->parse_history_count > 5) {
p->parse_last_mb = mb;
if (pc->frame_start_found) {
if (mb <= last_mb) {
i -= p->parse_history_count - 1;
p->parse_history_count = 0;
goto found;
}
} else
pc->frame_start_found = 1;
p->parse_history_count = 0;
state = 7;
}
}
}
pc->state = state;
if (p->is_avc)
return next_avc;
return END_NOT_FOUND;
found:
pc->state = 7;
pc->frame_start_found = 0;
if (p->is_avc)
return next_avc;
return i - (state & 5);
}
static int scan_mmco_reset(AVCodecParserContext *s, GetBitContext *gb,
void *logctx)
{
H264PredWeightTable pwt;
int slice_type_nos = s->pict_type & 3;
H264ParseContext *p = s->priv_data;
int list_count, ref_count[2];
if (p->ps.pps->redundant_pic_cnt_present)
get_ue_golomb(gb); // redundant_pic_count
if (slice_type_nos == AV_PICTURE_TYPE_B)
get_bits1(gb); // direct_spatial_mv_pred
if (ff_h264_parse_ref_count(&list_count, ref_count, gb, p->ps.pps,
slice_type_nos, p->picture_structure, logctx) < 0)
return AVERROR_INVALIDDATA;
if (slice_type_nos != AV_PICTURE_TYPE_I) {
int list;
for (list = 0; list < list_count; list++) {
if (get_bits1(gb)) {
int index;
for (index = 0; ; index++) {
unsigned int reordering_of_pic_nums_idc = get_ue_golomb_31(gb);
if (reordering_of_pic_nums_idc < 3)
get_ue_golomb_long(gb);
else if (reordering_of_pic_nums_idc > 3) {
av_log(logctx, AV_LOG_ERROR,
"illegal reordering_of_pic_nums_idc %d\n",
reordering_of_pic_nums_idc);
return AVERROR_INVALIDDATA;
} else
break;
if (index >= ref_count[list]) {
av_log(logctx, AV_LOG_ERROR,
"reference count %d overflow\n", index);
return AVERROR_INVALIDDATA;
}
}
}
}
}
if ((p->ps.pps->weighted_pred && slice_type_nos == AV_PICTURE_TYPE_P) ||
(p->ps.pps->weighted_bipred_idc == 1 && slice_type_nos == AV_PICTURE_TYPE_B))
ff_h264_pred_weight_table(gb, p->ps.sps, ref_count, slice_type_nos,
&pwt, p->picture_structure, logctx);
if (get_bits1(gb)) { // adaptive_ref_pic_marking_mode_flag
int i;
for (i = 0; i < MAX_MMCO_COUNT; i++) {
MMCOOpcode opcode = get_ue_golomb_31(gb);
if (opcode > (unsigned) MMCO_LONG) {
av_log(logctx, AV_LOG_ERROR,
"illegal memory management control operation %d\n",
opcode);
return AVERROR_INVALIDDATA;
}
if (opcode == MMCO_END)
return 0;
else if (opcode == MMCO_RESET)
return 1;
if (opcode == MMCO_SHORT2UNUSED || opcode == MMCO_SHORT2LONG)
get_ue_golomb_long(gb); // difference_of_pic_nums_minus1
if (opcode == MMCO_SHORT2LONG || opcode == MMCO_LONG2UNUSED ||
opcode == MMCO_LONG || opcode == MMCO_SET_MAX_LONG)
get_ue_golomb_31(gb);
}
}
return 0;
}
/**
* Parse NAL units of found picture and decode some basic information.
*
* @param s parser context.
* @param avctx codec context.
* @param buf buffer with field/frame data.
* @param buf_size size of the buffer.
*/
static inline int parse_nal_units(AVCodecParserContext *s,
AVCodecContext *avctx,
const uint8_t * const buf, int buf_size)
{
H264ParseContext *p = s->priv_data;
H2645RBSP rbsp = { NULL };
H2645NAL nal = { NULL };
int buf_index, next_avc;
unsigned int pps_id;
unsigned int slice_type;
int state = -1, got_reset = 0;
int q264 = buf_size >=4 && !memcmp("Q264", buf, 4);
int field_poc[2];
int ret;
/* set some sane default values */
s->pict_type = AV_PICTURE_TYPE_I;
s->key_frame = 0;
s->picture_structure = AV_PICTURE_STRUCTURE_UNKNOWN;
ff_h264_sei_uninit(&p->sei);
p->sei.frame_packing.arrangement_cancel_flag = -1;
if (!buf_size)
return 0;
av_fast_padded_malloc(&rbsp.rbsp_buffer, &rbsp.rbsp_buffer_alloc_size, buf_size);
if (!rbsp.rbsp_buffer)
return AVERROR(ENOMEM);
buf_index = 0;
next_avc = p->is_avc ? 0 : buf_size;
for (;;) {
const SPS *sps;
int src_length, consumed, nalsize = 0;
if (buf_index >= next_avc) {
nalsize = get_nalsize(p->nal_length_size, buf, buf_size, &buf_index, avctx);
if (nalsize < 0)
break;
next_avc = buf_index + nalsize;
} else {
buf_index = find_start_code(buf, buf_size, buf_index, next_avc);
if (buf_index >= buf_size)
break;
if (buf_index >= next_avc)
continue;
}
src_length = next_avc - buf_index;
state = buf[buf_index];
switch (state & 0x1f) {
case H264_NAL_SLICE:
case H264_NAL_IDR_SLICE:
// Do not walk the whole buffer just to decode slice header
if ((state & 0x1f) == H264_NAL_IDR_SLICE || ((state >> 5) & 0x3) == 0) {
/* IDR or disposable slice
* No need to decode many bytes because MMCOs shall not be present. */
if (src_length > 60)
src_length = 60;
} else {
/* To decode up to MMCOs */
if (src_length > 1000)
src_length = 1000;
}
break;
}
consumed = ff_h2645_extract_rbsp(buf + buf_index, src_length, &rbsp, &nal, 1);
if (consumed < 0)
break;
buf_index += consumed;
ret = init_get_bits8(&nal.gb, nal.data, nal.size);
if (ret < 0)
goto fail;
get_bits1(&nal.gb);
nal.ref_idc = get_bits(&nal.gb, 2);
nal.type = get_bits(&nal.gb, 5);
switch (nal.type) {
case H264_NAL_SPS:
ff_h264_decode_seq_parameter_set(&nal.gb, avctx, &p->ps, 0);
break;
case H264_NAL_PPS:
ff_h264_decode_picture_parameter_set(&nal.gb, avctx, &p->ps,
nal.size_bits);
break;
case H264_NAL_SEI:
ff_h264_sei_decode(&p->sei, &nal.gb, &p->ps, avctx);
break;
case H264_NAL_IDR_SLICE:
s->key_frame = 1;
p->poc.prev_frame_num = 0;
p->poc.prev_frame_num_offset = 0;
p->poc.prev_poc_msb =
p->poc.prev_poc_lsb = 0;
/* fall through */
case H264_NAL_SLICE:
get_ue_golomb_long(&nal.gb); // skip first_mb_in_slice
slice_type = get_ue_golomb_31(&nal.gb);
s->pict_type = ff_h264_golomb_to_pict_type[slice_type % 5];
if (p->sei.recovery_point.recovery_frame_cnt >= 0) {
/* key frame, since recovery_frame_cnt is set */
s->key_frame = 1;
}
pps_id = get_ue_golomb(&nal.gb);
if (pps_id >= MAX_PPS_COUNT) {
av_log(avctx, AV_LOG_ERROR,
"pps_id %u out of range\n", pps_id);
goto fail;
}
if (!p->ps.pps_list[pps_id]) {
av_log(avctx, AV_LOG_ERROR,
"non-existing PPS %u referenced\n", pps_id);
goto fail;
}
av_buffer_unref(&p->ps.pps_ref);
p->ps.pps = NULL;
p->ps.sps = NULL;
p->ps.pps_ref = av_buffer_ref(p->ps.pps_list[pps_id]);
if (!p->ps.pps_ref)
goto fail;
p->ps.pps = (const PPS*)p->ps.pps_ref->data;
p->ps.sps = p->ps.pps->sps;
sps = p->ps.sps;
// heuristic to detect non marked keyframes
if (p->ps.sps->ref_frame_count <= 1 && p->ps.pps->ref_count[0] <= 1 && s->pict_type == AV_PICTURE_TYPE_I)
s->key_frame = 1;
p->poc.frame_num = get_bits(&nal.gb, sps->log2_max_frame_num);
s->coded_width = 16 * sps->mb_width;
s->coded_height = 16 * sps->mb_height;
s->width = s->coded_width - (sps->crop_right + sps->crop_left);
s->height = s->coded_height - (sps->crop_top + sps->crop_bottom);
if (s->width <= 0 || s->height <= 0) {
s->width = s->coded_width;
s->height = s->coded_height;
}
switch (sps->bit_depth_luma) {
case 9:
if (sps->chroma_format_idc == 3) s->format = AV_PIX_FMT_YUV444P9;
else if (sps->chroma_format_idc == 2) s->format = AV_PIX_FMT_YUV422P9;
else s->format = AV_PIX_FMT_YUV420P9;
break;
case 10:
if (sps->chroma_format_idc == 3) s->format = AV_PIX_FMT_YUV444P10;
else if (sps->chroma_format_idc == 2) s->format = AV_PIX_FMT_YUV422P10;
else s->format = AV_PIX_FMT_YUV420P10;
break;
case 8:
if (sps->chroma_format_idc == 3) s->format = AV_PIX_FMT_YUV444P;
else if (sps->chroma_format_idc == 2) s->format = AV_PIX_FMT_YUV422P;
else s->format = AV_PIX_FMT_YUV420P;
break;
default:
s->format = AV_PIX_FMT_NONE;
}
avctx->profile = ff_h264_get_profile(sps);
avctx->level = sps->level_idc;
if (sps->frame_mbs_only_flag) {
p->picture_structure = PICT_FRAME;
} else {
if (get_bits1(&nal.gb)) { // field_pic_flag
p->picture_structure = PICT_TOP_FIELD + get_bits1(&nal.gb); // bottom_field_flag
} else {
p->picture_structure = PICT_FRAME;
}
}
if (nal.type == H264_NAL_IDR_SLICE)
get_ue_golomb_long(&nal.gb); /* idr_pic_id */
if (sps->poc_type == 0) {
p->poc.poc_lsb = get_bits(&nal.gb, sps->log2_max_poc_lsb);
if (p->ps.pps->pic_order_present == 1 &&
p->picture_structure == PICT_FRAME)
p->poc.delta_poc_bottom = get_se_golomb(&nal.gb);
}
if (sps->poc_type == 1 &&
!sps->delta_pic_order_always_zero_flag) {
p->poc.delta_poc[0] = get_se_golomb(&nal.gb);
if (p->ps.pps->pic_order_present == 1 &&
p->picture_structure == PICT_FRAME)
p->poc.delta_poc[1] = get_se_golomb(&nal.gb);
}
/* Decode POC of this picture.
* The prev_ values needed for decoding POC of the next picture are not set here. */
field_poc[0] = field_poc[1] = INT_MAX;
ret = ff_h264_init_poc(field_poc, &s->output_picture_number, sps,
&p->poc, p->picture_structure, nal.ref_idc);
if (ret < 0)
goto fail;
/* Continue parsing to check if MMCO_RESET is present.
* FIXME: MMCO_RESET could appear in non-first slice.
* Maybe, we should parse all undisposable non-IDR slice of this
* picture until encountering MMCO_RESET in a slice of it. */
if (nal.ref_idc && nal.type != H264_NAL_IDR_SLICE) {
got_reset = scan_mmco_reset(s, &nal.gb, avctx);
if (got_reset < 0)
goto fail;
}
/* Set up the prev_ values for decoding POC of the next picture. */
p->poc.prev_frame_num = got_reset ? 0 : p->poc.frame_num;
p->poc.prev_frame_num_offset = got_reset ? 0 : p->poc.frame_num_offset;
if (nal.ref_idc != 0) {
if (!got_reset) {
p->poc.prev_poc_msb = p->poc.poc_msb;
p->poc.prev_poc_lsb = p->poc.poc_lsb;
} else {
p->poc.prev_poc_msb = 0;
p->poc.prev_poc_lsb =
p->picture_structure == PICT_BOTTOM_FIELD ? 0 : field_poc[0];
}
}
if (p->sei.picture_timing.present) {
ret = ff_h264_sei_process_picture_timing(&p->sei.picture_timing,
sps, avctx);
if (ret < 0) {
av_log(avctx, AV_LOG_ERROR, "Error processing the picture timing SEI\n");
p->sei.picture_timing.present = 0;
}
}
if (sps->pic_struct_present_flag && p->sei.picture_timing.present) {
switch (p->sei.picture_timing.pic_struct) {
case H264_SEI_PIC_STRUCT_TOP_FIELD:
case H264_SEI_PIC_STRUCT_BOTTOM_FIELD:
s->repeat_pict = 0;
break;
case H264_SEI_PIC_STRUCT_FRAME:
case H264_SEI_PIC_STRUCT_TOP_BOTTOM:
case H264_SEI_PIC_STRUCT_BOTTOM_TOP:
s->repeat_pict = 1;
break;
case H264_SEI_PIC_STRUCT_TOP_BOTTOM_TOP:
case H264_SEI_PIC_STRUCT_BOTTOM_TOP_BOTTOM:
s->repeat_pict = 2;
break;
case H264_SEI_PIC_STRUCT_FRAME_DOUBLING:
s->repeat_pict = 3;
break;
case H264_SEI_PIC_STRUCT_FRAME_TRIPLING:
s->repeat_pict = 5;
break;
default:
s->repeat_pict = p->picture_structure == PICT_FRAME ? 1 : 0;
break;
}
} else {
s->repeat_pict = p->picture_structure == PICT_FRAME ? 1 : 0;
}
if (p->picture_structure == PICT_FRAME) {
s->picture_structure = AV_PICTURE_STRUCTURE_FRAME;
if (sps->pic_struct_present_flag && p->sei.picture_timing.present) {
switch (p->sei.picture_timing.pic_struct) {
case H264_SEI_PIC_STRUCT_TOP_BOTTOM:
case H264_SEI_PIC_STRUCT_TOP_BOTTOM_TOP:
s->field_order = AV_FIELD_TT;
break;
case H264_SEI_PIC_STRUCT_BOTTOM_TOP:
case H264_SEI_PIC_STRUCT_BOTTOM_TOP_BOTTOM:
s->field_order = AV_FIELD_BB;
break;
default:
s->field_order = AV_FIELD_PROGRESSIVE;
break;
}
} else {
if (field_poc[0] < field_poc[1])
s->field_order = AV_FIELD_TT;
else if (field_poc[0] > field_poc[1])
s->field_order = AV_FIELD_BB;
else
s->field_order = AV_FIELD_PROGRESSIVE;
}
} else {
if (p->picture_structure == PICT_TOP_FIELD)
s->picture_structure = AV_PICTURE_STRUCTURE_TOP_FIELD;
else
s->picture_structure = AV_PICTURE_STRUCTURE_BOTTOM_FIELD;
if (p->poc.frame_num == p->last_frame_num &&
p->last_picture_structure != AV_PICTURE_STRUCTURE_UNKNOWN &&
p->last_picture_structure != AV_PICTURE_STRUCTURE_FRAME &&
p->last_picture_structure != s->picture_structure) {
if (p->last_picture_structure == AV_PICTURE_STRUCTURE_TOP_FIELD)
s->field_order = AV_FIELD_TT;
else
s->field_order = AV_FIELD_BB;
} else {
s->field_order = AV_FIELD_UNKNOWN;
}
p->last_picture_structure = s->picture_structure;
p->last_frame_num = p->poc.frame_num;
}
av_freep(&rbsp.rbsp_buffer);
return 0; /* no need to evaluate the rest */
}
}
if (q264) {
av_freep(&rbsp.rbsp_buffer);
return 0;
}
/* didn't find a picture! */
av_log(avctx, AV_LOG_ERROR, "missing picture in access unit with size %d\n", buf_size);
fail:
av_freep(&rbsp.rbsp_buffer);
return -1;
}
static int h264_parse(AVCodecParserContext *s,
AVCodecContext *avctx,
const uint8_t **poutbuf, int *poutbuf_size,
const uint8_t *buf, int buf_size)
{
H264ParseContext *p = s->priv_data;
ParseContext *pc = &p->pc;
int next;
if (!p->got_first) {
p->got_first = 1;
if (avctx->extradata_size) {
ff_h264_decode_extradata(avctx->extradata, avctx->extradata_size,
&p->ps, &p->is_avc, &p->nal_length_size,
avctx->err_recognition, avctx);
}
}
if (s->flags & PARSER_FLAG_COMPLETE_FRAMES) {
next = buf_size;
} else {
next = h264_find_frame_end(p, buf, buf_size, avctx);
if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
*poutbuf = NULL;
*poutbuf_size = 0;
return buf_size;
}
if (next < 0 && next != END_NOT_FOUND) {
av_assert1(pc->last_index + next >= 0);
h264_find_frame_end(p, &pc->buffer[pc->last_index + next], -next, avctx); // update state
}
}
parse_nal_units(s, avctx, buf, buf_size);
if (avctx->framerate.num)
avctx->time_base = av_inv_q(av_mul_q(avctx->framerate, (AVRational){avctx->ticks_per_frame, 1}));
if (p->sei.picture_timing.cpb_removal_delay >= 0) {
s->dts_sync_point = p->sei.buffering_period.present;
s->dts_ref_dts_delta = p->sei.picture_timing.cpb_removal_delay;
s->pts_dts_delta = p->sei.picture_timing.dpb_output_delay;
} else {
s->dts_sync_point = INT_MIN;
s->dts_ref_dts_delta = INT_MIN;
s->pts_dts_delta = INT_MIN;
}
if (s->flags & PARSER_FLAG_ONCE) {
s->flags &= PARSER_FLAG_COMPLETE_FRAMES;
}
if (s->dts_sync_point >= 0) {
int64_t den = avctx->time_base.den * (int64_t)avctx->pkt_timebase.num;
if (den > 0) {
int64_t num = avctx->time_base.num * (int64_t)avctx->pkt_timebase.den;
if (s->dts != AV_NOPTS_VALUE) {
// got DTS from the stream, update reference timestamp
p->reference_dts = s->dts - av_rescale(s->dts_ref_dts_delta, num, den);
} else if (p->reference_dts != AV_NOPTS_VALUE) {
// compute DTS based on reference timestamp
s->dts = p->reference_dts + av_rescale(s->dts_ref_dts_delta, num, den);
}
if (p->reference_dts != AV_NOPTS_VALUE && s->pts == AV_NOPTS_VALUE)
s->pts = s->dts + av_rescale(s->pts_dts_delta, num, den);
if (s->dts_sync_point > 0)
p->reference_dts = s->dts; // new reference
}
}
*poutbuf = buf;
*poutbuf_size = buf_size;
return next;
}
static int h264_split(AVCodecContext *avctx,
const uint8_t *buf, int buf_size)
{
uint32_t state = -1;
int has_sps = 0;
int has_pps = 0;
const uint8_t *ptr = buf, *end = buf + buf_size;
int nalu_type;
while (ptr < end) {
ptr = avpriv_find_start_code(ptr, end, &state);
if ((state & 0xFFFFFF00) != 0x100)
break;
nalu_type = state & 0x1F;
if (nalu_type == H264_NAL_SPS) {
has_sps = 1;
} else if (nalu_type == H264_NAL_PPS)
has_pps = 1;
/* else if (nalu_type == 0x01 ||
* nalu_type == 0x02 ||
* nalu_type == 0x05) {
* }
*/
else if ((nalu_type != H264_NAL_SEI || has_pps) &&
nalu_type != H264_NAL_AUD && nalu_type != H264_NAL_SPS_EXT &&
nalu_type != 0x0f) {
if (has_sps) {
while (ptr - 4 > buf && ptr[-5] == 0)
ptr--;
return ptr - 4 - buf;
}
}
}
return 0;
}
static void h264_close(AVCodecParserContext *s)
{
H264ParseContext *p = s->priv_data;
ParseContext *pc = &p->pc;
av_freep(&pc->buffer);
ff_h264_sei_uninit(&p->sei);
ff_h264_ps_uninit(&p->ps);
}
static av_cold int init(AVCodecParserContext *s)
{
H264ParseContext *p = s->priv_data;
p->reference_dts = AV_NOPTS_VALUE;
p->last_frame_num = INT_MAX;
ff_h264dsp_init(&p->h264dsp, 8, 1);
return 0;
}
AVCodecParser ff_h264_parser = {
.codec_ids = { AV_CODEC_ID_H264 },
.priv_data_size = sizeof(H264ParseContext),
.parser_init = init,
.parser_parse = h264_parse,
.parser_close = h264_close,
.split = h264_split,
};