/libavcodec/h264_parser.c
C | 712 lines | 578 code | 77 blank | 57 comment | 226 complexity | ba218d4b72e90d48fb08b5d544c6c196 MD5 | raw file
1/* 2 * H.26L/H.264/AVC/JVT/14496-10/... parser 3 * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at> 4 * 5 * This file is part of FFmpeg. 6 * 7 * FFmpeg is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2.1 of the License, or (at your option) any later version. 11 * 12 * FFmpeg is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with FFmpeg; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 20 */ 21 22/** 23 * @file 24 * H.264 / AVC / MPEG-4 part10 parser. 25 * @author Michael Niedermayer <michaelni@gmx.at> 26 */ 27 28#define UNCHECKED_BITSTREAM_READER 1 29 30#include <assert.h> 31#include <stdint.h> 32 33#include "libavutil/avutil.h" 34#include "libavutil/error.h" 35#include "libavutil/log.h" 36#include "libavutil/mem.h" 37#include "libavutil/pixfmt.h" 38 39#include "avcodec.h" 40#include "get_bits.h" 41#include "golomb.h" 42#include "h264.h" 43#include "h264_sei.h" 44#include "h264_ps.h" 45#include "h264data.h" 46#include "internal.h" 47#include "mpegutils.h" 48#include "parser.h" 49 50typedef struct H264ParseContext { 51 ParseContext pc; 52 H264ParamSets ps; 53 H264DSPContext h264dsp; 54 H264POCContext poc; 55 H264SEIContext sei; 56 int is_avc; 57 int nal_length_size; 58 int got_first; 59 int picture_structure; 60 uint8_t parse_history[6]; 61 int parse_history_count; 62 int parse_last_mb; 63 int64_t reference_dts; 64 int last_frame_num, last_picture_structure; 65} H264ParseContext; 66 67 68static int h264_find_frame_end(H264ParseContext *p, const uint8_t *buf, 69 int buf_size, void *logctx) 70{ 71 int i, j; 72 uint32_t state; 73 ParseContext *pc = &p->pc; 74 75 int next_avc = p->is_avc ? 0 : buf_size; 76// mb_addr= pc->mb_addr - 1; 77 state = pc->state; 78 if (state > 13) 79 state = 7; 80 81 if (p->is_avc && !p->nal_length_size) 82 av_log(logctx, AV_LOG_ERROR, "AVC-parser: nal length size invalid\n"); 83 84 for (i = 0; i < buf_size; i++) { 85 if (i >= next_avc) { 86 int nalsize = 0; 87 i = next_avc; 88 for (j = 0; j < p->nal_length_size; j++) 89 nalsize = (nalsize << 8) | buf[i++]; 90 if (nalsize <= 0 || nalsize > buf_size - i) { 91 av_log(logctx, AV_LOG_ERROR, "AVC-parser: nal size %d remaining %d\n", nalsize, buf_size - i); 92 return buf_size; 93 } 94 next_avc = i + nalsize; 95 state = 5; 96 } 97 98 if (state == 7) { 99 i += p->h264dsp.startcode_find_candidate(buf + i, next_avc - i); 100 if (i < next_avc) 101 state = 2; 102 } else if (state <= 2) { 103 if (buf[i] == 1) 104 state ^= 5; // 2->7, 1->4, 0->5 105 else if (buf[i]) 106 state = 7; 107 else 108 state >>= 1; // 2->1, 1->0, 0->0 109 } else if (state <= 5) { 110 int nalu_type = buf[i] & 0x1F; 111 if (nalu_type == H264_NAL_SEI || nalu_type == H264_NAL_SPS || 112 nalu_type == H264_NAL_PPS || nalu_type == H264_NAL_AUD) { 113 if (pc->frame_start_found) { 114 i++; 115 goto found; 116 } 117 } else if (nalu_type == H264_NAL_SLICE || nalu_type == H264_NAL_DPA || 118 nalu_type == H264_NAL_IDR_SLICE) { 119 state += 8; 120 continue; 121 } 122 state = 7; 123 } else { 124 unsigned int mb, last_mb = p->parse_last_mb; 125 GetBitContext gb; 126 p->parse_history[p->parse_history_count++] = buf[i]; 127 128 init_get_bits(&gb, p->parse_history, 8*p->parse_history_count); 129 mb= get_ue_golomb_long(&gb); 130 if (get_bits_left(&gb) > 0 || p->parse_history_count > 5) { 131 p->parse_last_mb = mb; 132 if (pc->frame_start_found) { 133 if (mb <= last_mb) { 134 i -= p->parse_history_count - 1; 135 p->parse_history_count = 0; 136 goto found; 137 } 138 } else 139 pc->frame_start_found = 1; 140 p->parse_history_count = 0; 141 state = 7; 142 } 143 } 144 } 145 pc->state = state; 146 if (p->is_avc) 147 return next_avc; 148 return END_NOT_FOUND; 149 150found: 151 pc->state = 7; 152 pc->frame_start_found = 0; 153 if (p->is_avc) 154 return next_avc; 155 return i - (state & 5); 156} 157 158static int scan_mmco_reset(AVCodecParserContext *s, GetBitContext *gb, 159 void *logctx) 160{ 161 H264PredWeightTable pwt; 162 int slice_type_nos = s->pict_type & 3; 163 H264ParseContext *p = s->priv_data; 164 int list_count, ref_count[2]; 165 166 167 if (p->ps.pps->redundant_pic_cnt_present) 168 get_ue_golomb(gb); // redundant_pic_count 169 170 if (slice_type_nos == AV_PICTURE_TYPE_B) 171 get_bits1(gb); // direct_spatial_mv_pred 172 173 if (ff_h264_parse_ref_count(&list_count, ref_count, gb, p->ps.pps, 174 slice_type_nos, p->picture_structure, logctx) < 0) 175 return AVERROR_INVALIDDATA; 176 177 if (slice_type_nos != AV_PICTURE_TYPE_I) { 178 int list; 179 for (list = 0; list < list_count; list++) { 180 if (get_bits1(gb)) { 181 int index; 182 for (index = 0; ; index++) { 183 unsigned int reordering_of_pic_nums_idc = get_ue_golomb_31(gb); 184 185 if (reordering_of_pic_nums_idc < 3) 186 get_ue_golomb_long(gb); 187 else if (reordering_of_pic_nums_idc > 3) { 188 av_log(logctx, AV_LOG_ERROR, 189 "illegal reordering_of_pic_nums_idc %d\n", 190 reordering_of_pic_nums_idc); 191 return AVERROR_INVALIDDATA; 192 } else 193 break; 194 195 if (index >= ref_count[list]) { 196 av_log(logctx, AV_LOG_ERROR, 197 "reference count %d overflow\n", index); 198 return AVERROR_INVALIDDATA; 199 } 200 } 201 } 202 } 203 } 204 205 if ((p->ps.pps->weighted_pred && slice_type_nos == AV_PICTURE_TYPE_P) || 206 (p->ps.pps->weighted_bipred_idc == 1 && slice_type_nos == AV_PICTURE_TYPE_B)) 207 ff_h264_pred_weight_table(gb, p->ps.sps, ref_count, slice_type_nos, 208 &pwt, p->picture_structure, logctx); 209 210 if (get_bits1(gb)) { // adaptive_ref_pic_marking_mode_flag 211 int i; 212 for (i = 0; i < MAX_MMCO_COUNT; i++) { 213 MMCOOpcode opcode = get_ue_golomb_31(gb); 214 if (opcode > (unsigned) MMCO_LONG) { 215 av_log(logctx, AV_LOG_ERROR, 216 "illegal memory management control operation %d\n", 217 opcode); 218 return AVERROR_INVALIDDATA; 219 } 220 if (opcode == MMCO_END) 221 return 0; 222 else if (opcode == MMCO_RESET) 223 return 1; 224 225 if (opcode == MMCO_SHORT2UNUSED || opcode == MMCO_SHORT2LONG) 226 get_ue_golomb_long(gb); // difference_of_pic_nums_minus1 227 if (opcode == MMCO_SHORT2LONG || opcode == MMCO_LONG2UNUSED || 228 opcode == MMCO_LONG || opcode == MMCO_SET_MAX_LONG) 229 get_ue_golomb_31(gb); 230 } 231 } 232 233 return 0; 234} 235 236/** 237 * Parse NAL units of found picture and decode some basic information. 238 * 239 * @param s parser context. 240 * @param avctx codec context. 241 * @param buf buffer with field/frame data. 242 * @param buf_size size of the buffer. 243 */ 244static inline int parse_nal_units(AVCodecParserContext *s, 245 AVCodecContext *avctx, 246 const uint8_t * const buf, int buf_size) 247{ 248 H264ParseContext *p = s->priv_data; 249 H2645RBSP rbsp = { NULL }; 250 H2645NAL nal = { NULL }; 251 int buf_index, next_avc; 252 unsigned int pps_id; 253 unsigned int slice_type; 254 int state = -1, got_reset = 0; 255 int q264 = buf_size >=4 && !memcmp("Q264", buf, 4); 256 int field_poc[2]; 257 int ret; 258 259 /* set some sane default values */ 260 s->pict_type = AV_PICTURE_TYPE_I; 261 s->key_frame = 0; 262 s->picture_structure = AV_PICTURE_STRUCTURE_UNKNOWN; 263 264 ff_h264_sei_uninit(&p->sei); 265 p->sei.frame_packing.arrangement_cancel_flag = -1; 266 267 if (!buf_size) 268 return 0; 269 270 av_fast_padded_malloc(&rbsp.rbsp_buffer, &rbsp.rbsp_buffer_alloc_size, buf_size); 271 if (!rbsp.rbsp_buffer) 272 return AVERROR(ENOMEM); 273 274 buf_index = 0; 275 next_avc = p->is_avc ? 0 : buf_size; 276 for (;;) { 277 const SPS *sps; 278 int src_length, consumed, nalsize = 0; 279 280 if (buf_index >= next_avc) { 281 nalsize = get_nalsize(p->nal_length_size, buf, buf_size, &buf_index, avctx); 282 if (nalsize < 0) 283 break; 284 next_avc = buf_index + nalsize; 285 } else { 286 buf_index = find_start_code(buf, buf_size, buf_index, next_avc); 287 if (buf_index >= buf_size) 288 break; 289 if (buf_index >= next_avc) 290 continue; 291 } 292 src_length = next_avc - buf_index; 293 294 state = buf[buf_index]; 295 switch (state & 0x1f) { 296 case H264_NAL_SLICE: 297 case H264_NAL_IDR_SLICE: 298 // Do not walk the whole buffer just to decode slice header 299 if ((state & 0x1f) == H264_NAL_IDR_SLICE || ((state >> 5) & 0x3) == 0) { 300 /* IDR or disposable slice 301 * No need to decode many bytes because MMCOs shall not be present. */ 302 if (src_length > 60) 303 src_length = 60; 304 } else { 305 /* To decode up to MMCOs */ 306 if (src_length > 1000) 307 src_length = 1000; 308 } 309 break; 310 } 311 consumed = ff_h2645_extract_rbsp(buf + buf_index, src_length, &rbsp, &nal, 1); 312 if (consumed < 0) 313 break; 314 315 buf_index += consumed; 316 317 ret = init_get_bits8(&nal.gb, nal.data, nal.size); 318 if (ret < 0) 319 goto fail; 320 get_bits1(&nal.gb); 321 nal.ref_idc = get_bits(&nal.gb, 2); 322 nal.type = get_bits(&nal.gb, 5); 323 324 switch (nal.type) { 325 case H264_NAL_SPS: 326 ff_h264_decode_seq_parameter_set(&nal.gb, avctx, &p->ps, 0); 327 break; 328 case H264_NAL_PPS: 329 ff_h264_decode_picture_parameter_set(&nal.gb, avctx, &p->ps, 330 nal.size_bits); 331 break; 332 case H264_NAL_SEI: 333 ff_h264_sei_decode(&p->sei, &nal.gb, &p->ps, avctx); 334 break; 335 case H264_NAL_IDR_SLICE: 336 s->key_frame = 1; 337 338 p->poc.prev_frame_num = 0; 339 p->poc.prev_frame_num_offset = 0; 340 p->poc.prev_poc_msb = 341 p->poc.prev_poc_lsb = 0; 342 /* fall through */ 343 case H264_NAL_SLICE: 344 get_ue_golomb_long(&nal.gb); // skip first_mb_in_slice 345 slice_type = get_ue_golomb_31(&nal.gb); 346 s->pict_type = ff_h264_golomb_to_pict_type[slice_type % 5]; 347 if (p->sei.recovery_point.recovery_frame_cnt >= 0) { 348 /* key frame, since recovery_frame_cnt is set */ 349 s->key_frame = 1; 350 } 351 pps_id = get_ue_golomb(&nal.gb); 352 if (pps_id >= MAX_PPS_COUNT) { 353 av_log(avctx, AV_LOG_ERROR, 354 "pps_id %u out of range\n", pps_id); 355 goto fail; 356 } 357 if (!p->ps.pps_list[pps_id]) { 358 av_log(avctx, AV_LOG_ERROR, 359 "non-existing PPS %u referenced\n", pps_id); 360 goto fail; 361 } 362 363 av_buffer_unref(&p->ps.pps_ref); 364 p->ps.pps = NULL; 365 p->ps.sps = NULL; 366 p->ps.pps_ref = av_buffer_ref(p->ps.pps_list[pps_id]); 367 if (!p->ps.pps_ref) 368 goto fail; 369 p->ps.pps = (const PPS*)p->ps.pps_ref->data; 370 p->ps.sps = p->ps.pps->sps; 371 sps = p->ps.sps; 372 373 // heuristic to detect non marked keyframes 374 if (p->ps.sps->ref_frame_count <= 1 && p->ps.pps->ref_count[0] <= 1 && s->pict_type == AV_PICTURE_TYPE_I) 375 s->key_frame = 1; 376 377 p->poc.frame_num = get_bits(&nal.gb, sps->log2_max_frame_num); 378 379 s->coded_width = 16 * sps->mb_width; 380 s->coded_height = 16 * sps->mb_height; 381 s->width = s->coded_width - (sps->crop_right + sps->crop_left); 382 s->height = s->coded_height - (sps->crop_top + sps->crop_bottom); 383 if (s->width <= 0 || s->height <= 0) { 384 s->width = s->coded_width; 385 s->height = s->coded_height; 386 } 387 388 switch (sps->bit_depth_luma) { 389 case 9: 390 if (sps->chroma_format_idc == 3) s->format = AV_PIX_FMT_YUV444P9; 391 else if (sps->chroma_format_idc == 2) s->format = AV_PIX_FMT_YUV422P9; 392 else s->format = AV_PIX_FMT_YUV420P9; 393 break; 394 case 10: 395 if (sps->chroma_format_idc == 3) s->format = AV_PIX_FMT_YUV444P10; 396 else if (sps->chroma_format_idc == 2) s->format = AV_PIX_FMT_YUV422P10; 397 else s->format = AV_PIX_FMT_YUV420P10; 398 break; 399 case 8: 400 if (sps->chroma_format_idc == 3) s->format = AV_PIX_FMT_YUV444P; 401 else if (sps->chroma_format_idc == 2) s->format = AV_PIX_FMT_YUV422P; 402 else s->format = AV_PIX_FMT_YUV420P; 403 break; 404 default: 405 s->format = AV_PIX_FMT_NONE; 406 } 407 408 avctx->profile = ff_h264_get_profile(sps); 409 avctx->level = sps->level_idc; 410 411 if (sps->frame_mbs_only_flag) { 412 p->picture_structure = PICT_FRAME; 413 } else { 414 if (get_bits1(&nal.gb)) { // field_pic_flag 415 p->picture_structure = PICT_TOP_FIELD + get_bits1(&nal.gb); // bottom_field_flag 416 } else { 417 p->picture_structure = PICT_FRAME; 418 } 419 } 420 421 if (nal.type == H264_NAL_IDR_SLICE) 422 get_ue_golomb_long(&nal.gb); /* idr_pic_id */ 423 if (sps->poc_type == 0) { 424 p->poc.poc_lsb = get_bits(&nal.gb, sps->log2_max_poc_lsb); 425 426 if (p->ps.pps->pic_order_present == 1 && 427 p->picture_structure == PICT_FRAME) 428 p->poc.delta_poc_bottom = get_se_golomb(&nal.gb); 429 } 430 431 if (sps->poc_type == 1 && 432 !sps->delta_pic_order_always_zero_flag) { 433 p->poc.delta_poc[0] = get_se_golomb(&nal.gb); 434 435 if (p->ps.pps->pic_order_present == 1 && 436 p->picture_structure == PICT_FRAME) 437 p->poc.delta_poc[1] = get_se_golomb(&nal.gb); 438 } 439 440 /* Decode POC of this picture. 441 * The prev_ values needed for decoding POC of the next picture are not set here. */ 442 field_poc[0] = field_poc[1] = INT_MAX; 443 ret = ff_h264_init_poc(field_poc, &s->output_picture_number, sps, 444 &p->poc, p->picture_structure, nal.ref_idc); 445 if (ret < 0) 446 goto fail; 447 448 /* Continue parsing to check if MMCO_RESET is present. 449 * FIXME: MMCO_RESET could appear in non-first slice. 450 * Maybe, we should parse all undisposable non-IDR slice of this 451 * picture until encountering MMCO_RESET in a slice of it. */ 452 if (nal.ref_idc && nal.type != H264_NAL_IDR_SLICE) { 453 got_reset = scan_mmco_reset(s, &nal.gb, avctx); 454 if (got_reset < 0) 455 goto fail; 456 } 457 458 /* Set up the prev_ values for decoding POC of the next picture. */ 459 p->poc.prev_frame_num = got_reset ? 0 : p->poc.frame_num; 460 p->poc.prev_frame_num_offset = got_reset ? 0 : p->poc.frame_num_offset; 461 if (nal.ref_idc != 0) { 462 if (!got_reset) { 463 p->poc.prev_poc_msb = p->poc.poc_msb; 464 p->poc.prev_poc_lsb = p->poc.poc_lsb; 465 } else { 466 p->poc.prev_poc_msb = 0; 467 p->poc.prev_poc_lsb = 468 p->picture_structure == PICT_BOTTOM_FIELD ? 0 : field_poc[0]; 469 } 470 } 471 472 if (p->sei.picture_timing.present) { 473 ret = ff_h264_sei_process_picture_timing(&p->sei.picture_timing, 474 sps, avctx); 475 if (ret < 0) { 476 av_log(avctx, AV_LOG_ERROR, "Error processing the picture timing SEI\n"); 477 p->sei.picture_timing.present = 0; 478 } 479 } 480 481 if (sps->pic_struct_present_flag && p->sei.picture_timing.present) { 482 switch (p->sei.picture_timing.pic_struct) { 483 case H264_SEI_PIC_STRUCT_TOP_FIELD: 484 case H264_SEI_PIC_STRUCT_BOTTOM_FIELD: 485 s->repeat_pict = 0; 486 break; 487 case H264_SEI_PIC_STRUCT_FRAME: 488 case H264_SEI_PIC_STRUCT_TOP_BOTTOM: 489 case H264_SEI_PIC_STRUCT_BOTTOM_TOP: 490 s->repeat_pict = 1; 491 break; 492 case H264_SEI_PIC_STRUCT_TOP_BOTTOM_TOP: 493 case H264_SEI_PIC_STRUCT_BOTTOM_TOP_BOTTOM: 494 s->repeat_pict = 2; 495 break; 496 case H264_SEI_PIC_STRUCT_FRAME_DOUBLING: 497 s->repeat_pict = 3; 498 break; 499 case H264_SEI_PIC_STRUCT_FRAME_TRIPLING: 500 s->repeat_pict = 5; 501 break; 502 default: 503 s->repeat_pict = p->picture_structure == PICT_FRAME ? 1 : 0; 504 break; 505 } 506 } else { 507 s->repeat_pict = p->picture_structure == PICT_FRAME ? 1 : 0; 508 } 509 510 if (p->picture_structure == PICT_FRAME) { 511 s->picture_structure = AV_PICTURE_STRUCTURE_FRAME; 512 if (sps->pic_struct_present_flag && p->sei.picture_timing.present) { 513 switch (p->sei.picture_timing.pic_struct) { 514 case H264_SEI_PIC_STRUCT_TOP_BOTTOM: 515 case H264_SEI_PIC_STRUCT_TOP_BOTTOM_TOP: 516 s->field_order = AV_FIELD_TT; 517 break; 518 case H264_SEI_PIC_STRUCT_BOTTOM_TOP: 519 case H264_SEI_PIC_STRUCT_BOTTOM_TOP_BOTTOM: 520 s->field_order = AV_FIELD_BB; 521 break; 522 default: 523 s->field_order = AV_FIELD_PROGRESSIVE; 524 break; 525 } 526 } else { 527 if (field_poc[0] < field_poc[1]) 528 s->field_order = AV_FIELD_TT; 529 else if (field_poc[0] > field_poc[1]) 530 s->field_order = AV_FIELD_BB; 531 else 532 s->field_order = AV_FIELD_PROGRESSIVE; 533 } 534 } else { 535 if (p->picture_structure == PICT_TOP_FIELD) 536 s->picture_structure = AV_PICTURE_STRUCTURE_TOP_FIELD; 537 else 538 s->picture_structure = AV_PICTURE_STRUCTURE_BOTTOM_FIELD; 539 if (p->poc.frame_num == p->last_frame_num && 540 p->last_picture_structure != AV_PICTURE_STRUCTURE_UNKNOWN && 541 p->last_picture_structure != AV_PICTURE_STRUCTURE_FRAME && 542 p->last_picture_structure != s->picture_structure) { 543 if (p->last_picture_structure == AV_PICTURE_STRUCTURE_TOP_FIELD) 544 s->field_order = AV_FIELD_TT; 545 else 546 s->field_order = AV_FIELD_BB; 547 } else { 548 s->field_order = AV_FIELD_UNKNOWN; 549 } 550 p->last_picture_structure = s->picture_structure; 551 p->last_frame_num = p->poc.frame_num; 552 } 553 554 av_freep(&rbsp.rbsp_buffer); 555 return 0; /* no need to evaluate the rest */ 556 } 557 } 558 if (q264) { 559 av_freep(&rbsp.rbsp_buffer); 560 return 0; 561 } 562 /* didn't find a picture! */ 563 av_log(avctx, AV_LOG_ERROR, "missing picture in access unit with size %d\n", buf_size); 564fail: 565 av_freep(&rbsp.rbsp_buffer); 566 return -1; 567} 568 569static int h264_parse(AVCodecParserContext *s, 570 AVCodecContext *avctx, 571 const uint8_t **poutbuf, int *poutbuf_size, 572 const uint8_t *buf, int buf_size) 573{ 574 H264ParseContext *p = s->priv_data; 575 ParseContext *pc = &p->pc; 576 int next; 577 578 if (!p->got_first) { 579 p->got_first = 1; 580 if (avctx->extradata_size) { 581 ff_h264_decode_extradata(avctx->extradata, avctx->extradata_size, 582 &p->ps, &p->is_avc, &p->nal_length_size, 583 avctx->err_recognition, avctx); 584 } 585 } 586 587 if (s->flags & PARSER_FLAG_COMPLETE_FRAMES) { 588 next = buf_size; 589 } else { 590 next = h264_find_frame_end(p, buf, buf_size, avctx); 591 592 if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) { 593 *poutbuf = NULL; 594 *poutbuf_size = 0; 595 return buf_size; 596 } 597 598 if (next < 0 && next != END_NOT_FOUND) { 599 av_assert1(pc->last_index + next >= 0); 600 h264_find_frame_end(p, &pc->buffer[pc->last_index + next], -next, avctx); // update state 601 } 602 } 603 604 parse_nal_units(s, avctx, buf, buf_size); 605 606 if (avctx->framerate.num) 607 avctx->time_base = av_inv_q(av_mul_q(avctx->framerate, (AVRational){avctx->ticks_per_frame, 1})); 608 if (p->sei.picture_timing.cpb_removal_delay >= 0) { 609 s->dts_sync_point = p->sei.buffering_period.present; 610 s->dts_ref_dts_delta = p->sei.picture_timing.cpb_removal_delay; 611 s->pts_dts_delta = p->sei.picture_timing.dpb_output_delay; 612 } else { 613 s->dts_sync_point = INT_MIN; 614 s->dts_ref_dts_delta = INT_MIN; 615 s->pts_dts_delta = INT_MIN; 616 } 617 618 if (s->flags & PARSER_FLAG_ONCE) { 619 s->flags &= PARSER_FLAG_COMPLETE_FRAMES; 620 } 621 622 if (s->dts_sync_point >= 0) { 623 int64_t den = avctx->time_base.den * (int64_t)avctx->pkt_timebase.num; 624 if (den > 0) { 625 int64_t num = avctx->time_base.num * (int64_t)avctx->pkt_timebase.den; 626 if (s->dts != AV_NOPTS_VALUE) { 627 // got DTS from the stream, update reference timestamp 628 p->reference_dts = s->dts - av_rescale(s->dts_ref_dts_delta, num, den); 629 } else if (p->reference_dts != AV_NOPTS_VALUE) { 630 // compute DTS based on reference timestamp 631 s->dts = p->reference_dts + av_rescale(s->dts_ref_dts_delta, num, den); 632 } 633 634 if (p->reference_dts != AV_NOPTS_VALUE && s->pts == AV_NOPTS_VALUE) 635 s->pts = s->dts + av_rescale(s->pts_dts_delta, num, den); 636 637 if (s->dts_sync_point > 0) 638 p->reference_dts = s->dts; // new reference 639 } 640 } 641 642 *poutbuf = buf; 643 *poutbuf_size = buf_size; 644 return next; 645} 646 647static int h264_split(AVCodecContext *avctx, 648 const uint8_t *buf, int buf_size) 649{ 650 uint32_t state = -1; 651 int has_sps = 0; 652 int has_pps = 0; 653 const uint8_t *ptr = buf, *end = buf + buf_size; 654 int nalu_type; 655 656 while (ptr < end) { 657 ptr = avpriv_find_start_code(ptr, end, &state); 658 if ((state & 0xFFFFFF00) != 0x100) 659 break; 660 nalu_type = state & 0x1F; 661 if (nalu_type == H264_NAL_SPS) { 662 has_sps = 1; 663 } else if (nalu_type == H264_NAL_PPS) 664 has_pps = 1; 665 /* else if (nalu_type == 0x01 || 666 * nalu_type == 0x02 || 667 * nalu_type == 0x05) { 668 * } 669 */ 670 else if ((nalu_type != H264_NAL_SEI || has_pps) && 671 nalu_type != H264_NAL_AUD && nalu_type != H264_NAL_SPS_EXT && 672 nalu_type != 0x0f) { 673 if (has_sps) { 674 while (ptr - 4 > buf && ptr[-5] == 0) 675 ptr--; 676 return ptr - 4 - buf; 677 } 678 } 679 } 680 681 return 0; 682} 683 684static void h264_close(AVCodecParserContext *s) 685{ 686 H264ParseContext *p = s->priv_data; 687 ParseContext *pc = &p->pc; 688 689 av_freep(&pc->buffer); 690 691 ff_h264_sei_uninit(&p->sei); 692 ff_h264_ps_uninit(&p->ps); 693} 694 695static av_cold int init(AVCodecParserContext *s) 696{ 697 H264ParseContext *p = s->priv_data; 698 699 p->reference_dts = AV_NOPTS_VALUE; 700 p->last_frame_num = INT_MAX; 701 ff_h264dsp_init(&p->h264dsp, 8, 1); 702 return 0; 703} 704 705AVCodecParser ff_h264_parser = { 706 .codec_ids = { AV_CODEC_ID_H264 }, 707 .priv_data_size = sizeof(H264ParseContext), 708 .parser_init = init, 709 .parser_parse = h264_parse, 710 .parser_close = h264_close, 711 .split = h264_split, 712};