git.sesse.net Git - ffmpeg/blob - libavcodec/h264_parser.c

   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 Libav.
   6  *
   7  * Libav 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  * Libav 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 Libav; 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 #include <assert.h>
  29 #include <stdint.h>
  30
  31 #include "libavutil/avutil.h"
  32 #include "libavutil/error.h"
  33 #include "libavutil/log.h"
  34 #include "libavutil/mem.h"
  35 #include "libavutil/pixfmt.h"
  36
  37 #include "avcodec.h"
  38 #include "get_bits.h"
  39 #include "golomb.h"
  40 #include "h264.h"
  41 #include "h264_sei.h"
  42 #include "h264_ps.h"
  43 #include "h264data.h"
  44 #include "internal.h"
  45 #include "mpegutils.h"
  46 #include "parser.h"
  47
  48 typedef struct H264ParseContext {
  49     ParseContext pc;
  50     H264ParamSets ps;
  51     H264DSPContext h264dsp;
  52     H264POCContext poc;
  53     H264SEIContext sei;
  54     int is_avc;
  55     int nal_length_size;
  56     int got_first;
  57     int picture_structure;
  58 } H264ParseContext;
  59
  60
  61 static int h264_find_frame_end(H264ParseContext *p, const uint8_t *buf,
  62                                int buf_size)
  63 {
  64     int i;
  65     uint32_t state;
  66     ParseContext *pc = &p->pc;
  67 //    mb_addr= pc->mb_addr - 1;
  68     state = pc->state;
  69     if (state > 13)
  70         state = 7;
  71
  72     for (i = 0; i < buf_size; i++) {
  73         if (state == 7) {
  74             i += p->h264dsp.startcode_find_candidate(buf + i, buf_size - i);
  75             if (i < buf_size)
  76                 state = 2;
  77         } else if (state <= 2) {
  78             if (buf[i] == 1)
  79                 state ^= 5;            // 2->7, 1->4, 0->5
  80             else if (buf[i])
  81                 state = 7;
  82             else
  83                 state >>= 1;           // 2->1, 1->0, 0->0
  84         } else if (state <= 5) {
  85             int nalu_type = buf[i] & 0x1F;
  86             if (nalu_type == H264_NAL_SEI || nalu_type == H264_NAL_SPS ||
  87                 nalu_type == H264_NAL_PPS || nalu_type == H264_NAL_AUD) {
  88                 if (pc->frame_start_found) {
  89                     i++;
  90                     goto found;
  91                 }
  92             } else if (nalu_type == H264_NAL_SLICE || nalu_type == H264_NAL_DPA ||
  93                        nalu_type == H264_NAL_IDR_SLICE) {
  94                 if (pc->frame_start_found) {
  95                     state += 8;
  96                     continue;
  97                 } else
  98                     pc->frame_start_found = 1;
  99             }
 100             state = 7;
 101         } else {
 102             // first_mb_in_slice is 0, probably the first nal of a new slice
 103             if (buf[i] & 0x80)
 104                 goto found;
 105             state = 7;
 106         }
 107     }
 108     pc->state = state;
 109     return END_NOT_FOUND;
 110
 111 found:
 112     pc->state             = 7;
 113     pc->frame_start_found = 0;
 114     return i - (state & 5);
 115 }
 116
 117 static int scan_mmco_reset(AVCodecParserContext *s, GetBitContext *gb,
 118                            AVCodecContext *avctx)
 119 {
 120     H264PredWeightTable pwt;
 121     int slice_type_nos = s->pict_type & 3;
 122     H264ParseContext *p = s->priv_data;
 123     int list_count, ref_count[2];
 124
 125
 126     if (p->ps.pps->redundant_pic_cnt_present)
 127         get_ue_golomb(gb); // redundant_pic_count
 128
 129     if (slice_type_nos == AV_PICTURE_TYPE_B)
 130         get_bits1(gb); // direct_spatial_mv_pred
 131
 132     if (ff_h264_parse_ref_count(&list_count, ref_count, gb, p->ps.pps,
 133                                 slice_type_nos, p->picture_structure) < 0)
 134         return AVERROR_INVALIDDATA;
 135
 136     if (slice_type_nos != AV_PICTURE_TYPE_I) {
 137         int list;
 138         for (list = 0; list < list_count; list++) {
 139             if (get_bits1(gb)) {
 140                 int index;
 141                 for (index = 0; ; index++) {
 142                     unsigned int reordering_of_pic_nums_idc = get_ue_golomb_31(gb);
 143
 144                     if (reordering_of_pic_nums_idc < 3)
 145                         get_ue_golomb(gb);
 146                     else if (reordering_of_pic_nums_idc > 3) {
 147                         av_log(avctx, AV_LOG_ERROR,
 148                                "illegal reordering_of_pic_nums_idc %d\n",
 149                                reordering_of_pic_nums_idc);
 150                         return AVERROR_INVALIDDATA;
 151                     } else
 152                         break;
 153
 154                     if (index >= ref_count[list]) {
 155                         av_log(avctx, AV_LOG_ERROR,
 156                                "reference count %d overflow\n", index);
 157                         return AVERROR_INVALIDDATA;
 158                     }
 159                 }
 160             }
 161         }
 162     }
 163
 164     if ((p->ps.pps->weighted_pred && slice_type_nos == AV_PICTURE_TYPE_P) ||
 165         (p->ps.pps->weighted_bipred_idc == 1 && slice_type_nos == AV_PICTURE_TYPE_B))
 166         ff_h264_pred_weight_table(gb, p->ps.sps, ref_count, slice_type_nos,
 167                                   &pwt);
 168
 169     if (get_bits1(gb)) { // adaptive_ref_pic_marking_mode_flag
 170         int i;
 171         for (i = 0; i < MAX_MMCO_COUNT; i++) {
 172             MMCOOpcode opcode = get_ue_golomb_31(gb);
 173             if (opcode > (unsigned) MMCO_LONG) {
 174                 av_log(avctx, AV_LOG_ERROR,
 175                        "illegal memory management control operation %d\n",
 176                        opcode);
 177                 return AVERROR_INVALIDDATA;
 178             }
 179             if (opcode == MMCO_END)
 180                return 0;
 181             else if (opcode == MMCO_RESET)
 182                 return 1;
 183
 184             if (opcode == MMCO_SHORT2UNUSED || opcode == MMCO_SHORT2LONG)
 185                 get_ue_golomb(gb);
 186             if (opcode == MMCO_SHORT2LONG || opcode == MMCO_LONG2UNUSED ||
 187                 opcode == MMCO_LONG || opcode == MMCO_SET_MAX_LONG)
 188                 get_ue_golomb_31(gb);
 189         }
 190     }
 191
 192     return 0;
 193 }
 194
 195 /**
 196  * Parse NAL units of found picture and decode some basic information.
 197  *
 198  * @param s parser context.
 199  * @param avctx codec context.
 200  * @param buf buffer with field/frame data.
 201  * @param buf_size size of the buffer.
 202  */
 203 static inline int parse_nal_units(AVCodecParserContext *s,
 204                                   AVCodecContext *avctx,
 205                                   const uint8_t *buf, int buf_size)
 206 {
 207     H264ParseContext *p = s->priv_data;
 208     const uint8_t *buf_end = buf + buf_size;
 209
 210     H2645NAL nal = { NULL };
 211
 212     unsigned int pps_id;
 213     unsigned int slice_type;
 214     int state = -1, got_reset = 0;
 215     int field_poc[2];
 216     int ret;
 217
 218     /* set some sane default values */
 219     s->pict_type         = AV_PICTURE_TYPE_I;
 220     s->key_frame         = 0;
 221     s->picture_structure = AV_PICTURE_STRUCTURE_UNKNOWN;
 222
 223     ff_h264_sei_uninit(&p->sei);
 224
 225     if (!buf_size)
 226         return 0;
 227
 228     for (;;) {
 229         const SPS *sps;
 230         int src_length, consumed;
 231         buf = avpriv_find_start_code(buf, buf_end, &state);
 232         if (buf >= buf_end)
 233             break;
 234         --buf;
 235         src_length = buf_end - buf;
 236         switch (state & 0x1f) {
 237         case H264_NAL_SLICE:
 238         case H264_NAL_IDR_SLICE:
 239             // Do not walk the whole buffer just to decode slice header
 240             if ((state & 0x1f) == H264_NAL_IDR_SLICE || ((state >> 5) & 0x3) == 0) {
 241                 /* IDR or disposable slice
 242                  * No need to decode many bytes because MMCOs shall not be present. */
 243                 if (src_length > 60)
 244                     src_length = 60;
 245             } else {
 246                 /* To decode up to MMCOs */
 247                 if (src_length > 1000)
 248                     src_length = 1000;
 249             }
 250             break;
 251         }
 252
 253         consumed = ff_h2645_extract_rbsp(buf, src_length, &nal);
 254         if (consumed < 0)
 255             break;
 256
 257         ret = init_get_bits(&nal.gb, nal.data, nal.size * 8);
 258         if (ret < 0)
 259             goto fail;
 260         get_bits1(&nal.gb);
 261         nal.ref_idc = get_bits(&nal.gb, 2);
 262         nal.type    = get_bits(&nal.gb, 5);
 263
 264         switch (nal.type) {
 265         case H264_NAL_SPS:
 266             ff_h264_decode_seq_parameter_set(&nal.gb, avctx, &p->ps);
 267             break;
 268         case H264_NAL_PPS:
 269             ff_h264_decode_picture_parameter_set(&nal.gb, avctx, &p->ps,
 270                                                  nal.size_bits);
 271             break;
 272         case H264_NAL_SEI:
 273             ff_h264_sei_decode(&p->sei, &nal.gb, &p->ps, avctx);
 274             break;
 275         case H264_NAL_IDR_SLICE:
 276             s->key_frame = 1;
 277
 278             p->poc.prev_frame_num        = 0;
 279             p->poc.prev_frame_num_offset = 0;
 280             p->poc.prev_poc_msb          =
 281             p->poc.prev_poc_lsb          = 0;
 282         /* fall through */
 283         case H264_NAL_SLICE:
 284             get_ue_golomb(&nal.gb);  // skip first_mb_in_slice
 285             slice_type   = get_ue_golomb_31(&nal.gb);
 286             s->pict_type = ff_h264_golomb_to_pict_type[slice_type % 5];
 287             if (p->sei.recovery_point.recovery_frame_cnt >= 0) {
 288                 /* key frame, since recovery_frame_cnt is set */
 289                 s->key_frame = 1;
 290             }
 291             pps_id = get_ue_golomb(&nal.gb);
 292             if (pps_id >= MAX_PPS_COUNT) {
 293                 av_log(avctx, AV_LOG_ERROR,
 294                        "pps_id %u out of range\n", pps_id);
 295                 goto fail;
 296             }
 297             if (!p->ps.pps_list[pps_id]) {
 298                 av_log(avctx, AV_LOG_ERROR,
 299                        "non-existing PPS %u referenced\n", pps_id);
 300                 goto fail;
 301             }
 302             p->ps.pps = (const PPS*)p->ps.pps_list[pps_id]->data;
 303             if (!p->ps.sps_list[p->ps.pps->sps_id]) {
 304                 av_log(avctx, AV_LOG_ERROR,
 305                        "non-existing SPS %u referenced\n", p->ps.pps->sps_id);
 306                 goto fail;
 307             }
 308             p->ps.sps = (SPS*)p->ps.sps_list[p->ps.pps->sps_id]->data;
 309
 310             sps = p->ps.sps;
 311
 312             p->poc.frame_num = get_bits(&nal.gb, sps->log2_max_frame_num);
 313
 314             s->coded_width  = 16 * sps->mb_width;
 315             s->coded_height = 16 * sps->mb_height;
 316             s->width        = s->coded_width  - (sps->crop_right + sps->crop_left);
 317             s->height       = s->coded_height - (sps->crop_top   + sps->crop_bottom);
 318             if (s->width <= 0 || s->height <= 0) {
 319                 s->width  = s->coded_width;
 320                 s->height = s->coded_height;
 321             }
 322
 323             switch (sps->bit_depth_luma) {
 324             case 9:
 325                 if (sps->chroma_format_idc == 3)      s->format = AV_PIX_FMT_YUV444P9;
 326                 else if (sps->chroma_format_idc == 2) s->format = AV_PIX_FMT_YUV422P9;
 327                 else                                  s->format = AV_PIX_FMT_YUV420P9;
 328                 break;
 329             case 10:
 330                 if (sps->chroma_format_idc == 3)      s->format = AV_PIX_FMT_YUV444P10;
 331                 else if (sps->chroma_format_idc == 2) s->format = AV_PIX_FMT_YUV422P10;
 332                 else                                  s->format = AV_PIX_FMT_YUV420P10;
 333                 break;
 334             case 8:
 335                 if (sps->chroma_format_idc == 3)      s->format = AV_PIX_FMT_YUV444P;
 336                 else if (sps->chroma_format_idc == 2) s->format = AV_PIX_FMT_YUV422P;
 337                 else                                  s->format = AV_PIX_FMT_YUV420P;
 338                 break;
 339             default:
 340                 s->format = AV_PIX_FMT_NONE;
 341             }
 342
 343             avctx->profile = ff_h264_get_profile(sps);
 344             avctx->level   = sps->level_idc;
 345
 346             if (sps->frame_mbs_only_flag) {
 347                 p->picture_structure = PICT_FRAME;
 348             } else {
 349                 if (get_bits1(&nal.gb)) { // field_pic_flag
 350                     p->picture_structure = PICT_TOP_FIELD + get_bits1(&nal.gb); // bottom_field_flag
 351                 } else {
 352                     p->picture_structure = PICT_FRAME;
 353                 }
 354             }
 355
 356             if (nal.type == H264_NAL_IDR_SLICE)
 357                 get_ue_golomb(&nal.gb); /* idr_pic_id */
 358             if (sps->poc_type == 0) {
 359                 p->poc.poc_lsb = get_bits(&nal.gb, sps->log2_max_poc_lsb);
 360
 361                 if (p->ps.pps->pic_order_present == 1 &&
 362                     p->picture_structure == PICT_FRAME)
 363                     p->poc.delta_poc_bottom = get_se_golomb(&nal.gb);
 364             }
 365
 366             if (sps->poc_type == 1 &&
 367                 !sps->delta_pic_order_always_zero_flag) {
 368                 p->poc.delta_poc[0] = get_se_golomb(&nal.gb);
 369
 370                 if (p->ps.pps->pic_order_present == 1 &&
 371                     p->picture_structure == PICT_FRAME)
 372                     p->poc.delta_poc[1] = get_se_golomb(&nal.gb);
 373             }
 374
 375             /* Decode POC of this picture.
 376              * The prev_ values needed for decoding POC of the next picture are not set here. */
 377             field_poc[0] = field_poc[1] = INT_MAX;
 378             ff_h264_init_poc(field_poc, &s->output_picture_number, sps,
 379                              &p->poc, p->picture_structure, nal.ref_idc);
 380
 381             /* Continue parsing to check if MMCO_RESET is present.
 382              * FIXME: MMCO_RESET could appear in non-first slice.
 383              *        Maybe, we should parse all undisposable non-IDR slice of this
 384              *        picture until encountering MMCO_RESET in a slice of it. */
 385             if (nal.ref_idc && nal.type != H264_NAL_IDR_SLICE) {
 386                 got_reset = scan_mmco_reset(s, &nal.gb, avctx);
 387                 if (got_reset < 0)
 388                     goto fail;
 389             }
 390
 391             /* Set up the prev_ values for decoding POC of the next picture. */
 392             p->poc.prev_frame_num        = got_reset ? 0 : p->poc.frame_num;
 393             p->poc.prev_frame_num_offset = got_reset ? 0 : p->poc.frame_num_offset;
 394             if (nal.ref_idc != 0) {
 395                 if (!got_reset) {
 396                     p->poc.prev_poc_msb = p->poc.poc_msb;
 397                     p->poc.prev_poc_lsb = p->poc.poc_lsb;
 398                 } else {
 399                     p->poc.prev_poc_msb = 0;
 400                     p->poc.prev_poc_lsb =
 401                         p->picture_structure == PICT_BOTTOM_FIELD ? 0 : field_poc[0];
 402                 }
 403             }
 404
 405             if (sps->pic_struct_present_flag) {
 406                 switch (p->sei.picture_timing.pic_struct) {
 407                 case SEI_PIC_STRUCT_TOP_FIELD:
 408                 case SEI_PIC_STRUCT_BOTTOM_FIELD:
 409                     s->repeat_pict = 0;
 410                     break;
 411                 case SEI_PIC_STRUCT_FRAME:
 412                 case SEI_PIC_STRUCT_TOP_BOTTOM:
 413                 case SEI_PIC_STRUCT_BOTTOM_TOP:
 414                     s->repeat_pict = 1;
 415                     break;
 416                 case SEI_PIC_STRUCT_TOP_BOTTOM_TOP:
 417                 case SEI_PIC_STRUCT_BOTTOM_TOP_BOTTOM:
 418                     s->repeat_pict = 2;
 419                     break;
 420                 case SEI_PIC_STRUCT_FRAME_DOUBLING:
 421                     s->repeat_pict = 3;
 422                     break;
 423                 case SEI_PIC_STRUCT_FRAME_TRIPLING:
 424                     s->repeat_pict = 5;
 425                     break;
 426                 default:
 427                     s->repeat_pict = p->picture_structure == PICT_FRAME ? 1 : 0;
 428                     break;
 429                 }
 430             } else {
 431                 s->repeat_pict = p->picture_structure == PICT_FRAME ? 1 : 0;
 432             }
 433
 434             if (p->picture_structure == PICT_FRAME) {
 435                 s->picture_structure = AV_PICTURE_STRUCTURE_FRAME;
 436                 if (sps->pic_struct_present_flag) {
 437                     switch (p->sei.picture_timing.pic_struct) {
 438                     case SEI_PIC_STRUCT_TOP_BOTTOM:
 439                     case SEI_PIC_STRUCT_TOP_BOTTOM_TOP:
 440                         s->field_order = AV_FIELD_TT;
 441                         break;
 442                     case SEI_PIC_STRUCT_BOTTOM_TOP:
 443                     case SEI_PIC_STRUCT_BOTTOM_TOP_BOTTOM:
 444                         s->field_order = AV_FIELD_BB;
 445                         break;
 446                     default:
 447                         s->field_order = AV_FIELD_PROGRESSIVE;
 448                         break;
 449                     }
 450                 } else {
 451                     if (field_poc[0] < field_poc[1])
 452                         s->field_order = AV_FIELD_TT;
 453                     else if (field_poc[0] > field_poc[1])
 454                         s->field_order = AV_FIELD_BB;
 455                     else
 456                         s->field_order = AV_FIELD_PROGRESSIVE;
 457                 }
 458             } else {
 459                 if (p->picture_structure == PICT_TOP_FIELD)
 460                     s->picture_structure = AV_PICTURE_STRUCTURE_TOP_FIELD;
 461                 else
 462                     s->picture_structure = AV_PICTURE_STRUCTURE_BOTTOM_FIELD;
 463                 s->field_order = AV_FIELD_UNKNOWN;
 464             }
 465
 466             av_freep(&nal.rbsp_buffer);
 467             return 0; /* no need to evaluate the rest */
 468         }
 469         buf += consumed;
 470     }
 471     /* didn't find a picture! */
 472     av_log(avctx, AV_LOG_ERROR, "missing picture in access unit\n");
 473 fail:
 474     av_freep(&nal.rbsp_buffer);
 475     return -1;
 476 }
 477
 478 static int h264_parse(AVCodecParserContext *s,
 479                       AVCodecContext *avctx,
 480                       const uint8_t **poutbuf, int *poutbuf_size,
 481                       const uint8_t *buf, int buf_size)
 482 {
 483     H264ParseContext *p = s->priv_data;
 484     ParseContext *pc = &p->pc;
 485     int next;
 486
 487     if (!p->got_first) {
 488         p->got_first = 1;
 489         if (avctx->extradata_size) {
 490             ff_h264_decode_extradata(avctx->extradata, avctx->extradata_size,
 491                                      &p->ps, &p->is_avc, &p->nal_length_size,
 492                                      avctx->err_recognition, avctx);
 493         }
 494     }
 495
 496     if (s->flags & PARSER_FLAG_COMPLETE_FRAMES) {
 497         next = buf_size;
 498     } else {
 499         next = h264_find_frame_end(p, buf, buf_size);
 500
 501         if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
 502             *poutbuf      = NULL;
 503             *poutbuf_size = 0;
 504             return buf_size;
 505         }
 506
 507         if (next < 0 && next != END_NOT_FOUND) {
 508             assert(pc->last_index + next >= 0);
 509             h264_find_frame_end(p, &pc->buffer[pc->last_index + next], -next); // update state
 510         }
 511     }
 512
 513     parse_nal_units(s, avctx, buf, buf_size);
 514
 515     if (p->sei.picture_timing.cpb_removal_delay >= 0) {
 516         s->dts_sync_point    = p->sei.buffering_period.present;
 517         s->dts_ref_dts_delta = p->sei.picture_timing.cpb_removal_delay;
 518         s->pts_dts_delta     = p->sei.picture_timing.dpb_output_delay;
 519     } else {
 520         s->dts_sync_point    = INT_MIN;
 521         s->dts_ref_dts_delta = INT_MIN;
 522         s->pts_dts_delta     = INT_MIN;
 523     }
 524
 525     if (s->flags & PARSER_FLAG_ONCE) {
 526         s->flags &= PARSER_FLAG_COMPLETE_FRAMES;
 527     }
 528
 529     *poutbuf      = buf;
 530     *poutbuf_size = buf_size;
 531     return next;
 532 }
 533
 534 static int h264_split(AVCodecContext *avctx,
 535                       const uint8_t *buf, int buf_size)
 536 {
 537     int i;
 538     uint32_t state = -1;
 539     int has_sps    = 0;
 540
 541     for (i = 0; i <= buf_size; i++) {
 542         if ((state & 0xFFFFFF1F) == 0x107)
 543             has_sps = 1;
 544         /*  if((state&0xFFFFFF1F) == 0x101 ||
 545          *     (state&0xFFFFFF1F) == 0x102 ||
 546          *     (state&0xFFFFFF1F) == 0x105) {
 547          *  }
 548          */
 549         if ((state & 0xFFFFFF00) == 0x100 && (state & 0xFFFFFF1F) != 0x106 &&
 550             (state & 0xFFFFFF1F) != 0x107 && (state & 0xFFFFFF1F) != 0x108 &&
 551             (state & 0xFFFFFF1F) != 0x109 && (state & 0xFFFFFF1F) != 0x10d &&
 552             (state & 0xFFFFFF1F) != 0x10f) {
 553             if (has_sps) {
 554                 while (i > 4 && buf[i - 5] == 0)
 555                     i--;
 556                 return i - 4;
 557             }
 558         }
 559         if (i < buf_size)
 560             state = (state << 8) | buf[i];
 561     }
 562     return 0;
 563 }
 564
 565 static void h264_close(AVCodecParserContext *s)
 566 {
 567     H264ParseContext *p = s->priv_data;
 568     ParseContext *pc = &p->pc;
 569     int i;
 570
 571     av_free(pc->buffer);
 572
 573     ff_h264_sei_uninit(&p->sei);
 574
 575     for (i = 0; i < FF_ARRAY_ELEMS(p->ps.sps_list); i++)
 576         av_buffer_unref(&p->ps.sps_list[i]);
 577
 578     for (i = 0; i < FF_ARRAY_ELEMS(p->ps.pps_list); i++)
 579         av_buffer_unref(&p->ps.pps_list[i]);
 580 }
 581
 582 static av_cold int init(AVCodecParserContext *s)
 583 {
 584     H264ParseContext *p = s->priv_data;
 585
 586     ff_h264dsp_init(&p->h264dsp, 8, 1);
 587     return 0;
 588 }
 589
 590 AVCodecParser ff_h264_parser = {
 591     .codec_ids      = { AV_CODEC_ID_H264 },
 592     .priv_data_size = sizeof(H264ParseContext),
 593     .parser_init    = init,
 594     .parser_parse   = h264_parse,
 595     .parser_close   = h264_close,
 596     .split          = h264_split,
 597 };