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   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 / MPEG4 part10 parser.
  25  * @author Michael Niedermayer <michaelni@gmx.at>
  26  */
  27
  28 #define UNCHECKED_BITSTREAM_READER 1
  29
  30 #include "libavutil/attributes.h"
  31 #include "parser.h"
  32 #include "h264data.h"
  33 #include "golomb.h"
  34 #include "internal.h"
  35 #include "mpegutils.h"
  36
  37 typedef struct H264ParseContext {
  38     H264Context h;
  39     ParseContext pc;
  40     int got_first;
  41 } H264ParseContext;
  42
  43
  44 static int h264_find_frame_end(H264ParseContext *p, const uint8_t *buf,
  45                                int buf_size)
  46 {
  47     H264Context *h = &p->h;
  48     int i, j;
  49     uint32_t state;
  50     ParseContext *pc = &p->pc;
  51
  52     int next_avc= h->is_avc ? 0 : buf_size;
  53 //    mb_addr= pc->mb_addr - 1;
  54     state = pc->state;
  55     if (state > 13)
  56         state = 7;
  57
  58     if (h->is_avc && !h->nal_length_size)
  59         av_log(h->avctx, AV_LOG_ERROR, "AVC-parser: nal length size invalid\n");
  60
  61     for (i = 0; i < buf_size; i++) {
  62         if (i >= next_avc) {
  63             int nalsize = 0;
  64             i = next_avc;
  65             for (j = 0; j < h->nal_length_size; j++)
  66                 nalsize = (nalsize << 8) | buf[i++];
  67             if (nalsize <= 0 || nalsize > buf_size - i) {
  68                 av_log(h->avctx, AV_LOG_ERROR, "AVC-parser: nal size %d remaining %d\n", nalsize, buf_size - i);
  69                 return buf_size;
  70             }
  71             next_avc = i + nalsize;
  72             state    = 5;
  73         }
  74
  75         if (state == 7) {
  76             i += h->h264dsp.startcode_find_candidate(buf + i, next_avc - i);
  77             if (i < next_avc)
  78                 state = 2;
  79         } else if (state <= 2) {
  80             if (buf[i] == 1)
  81                 state ^= 5;            // 2->7, 1->4, 0->5
  82             else if (buf[i])
  83                 state = 7;
  84             else
  85                 state >>= 1;           // 2->1, 1->0, 0->0
  86         } else if (state <= 5) {
  87             int nalu_type = buf[i] & 0x1F;
  88             if (nalu_type == NAL_SEI || nalu_type == NAL_SPS ||
  89                 nalu_type == NAL_PPS || nalu_type == NAL_AUD) {
  90                 if (pc->frame_start_found) {
  91                     i++;
  92                     goto found;
  93                 }
  94             } else if (nalu_type == NAL_SLICE || nalu_type == NAL_DPA ||
  95                        nalu_type == NAL_IDR_SLICE) {
  96                 state += 8;
  97                 continue;
  98             }
  99             state = 7;
 100         } else {
 101             h->parse_history[h->parse_history_count++]= buf[i];
 102             if (h->parse_history_count>5) {
 103                 unsigned int mb, last_mb= h->parse_last_mb;
 104                 GetBitContext gb;
 105
 106                 init_get_bits(&gb, h->parse_history, 8*h->parse_history_count);
 107                 h->parse_history_count=0;
 108                 mb= get_ue_golomb_long(&gb);
 109                 h->parse_last_mb= mb;
 110                 if (pc->frame_start_found) {
 111                     if (mb <= last_mb)
 112                         goto found;
 113                 } else
 114                     pc->frame_start_found = 1;
 115                 state = 7;
 116             }
 117         }
 118     }
 119     pc->state = state;
 120     if (h->is_avc)
 121         return next_avc;
 122     return END_NOT_FOUND;
 123
 124 found:
 125     pc->state             = 7;
 126     pc->frame_start_found = 0;
 127     if (h->is_avc)
 128         return next_avc;
 129     return i - (state & 5) - 5 * (state > 7);
 130 }
 131
 132 static int scan_mmco_reset(AVCodecParserContext *s)
 133 {
 134     H264ParseContext *p = s->priv_data;
 135     H264Context      *h = &p->h;
 136
 137     h->slice_type_nos = s->pict_type & 3;
 138
 139     if (h->pps.redundant_pic_cnt_present)
 140         get_ue_golomb(&h->gb); // redundant_pic_count
 141
 142     if (ff_set_ref_count(h) < 0)
 143         return AVERROR_INVALIDDATA;
 144
 145     if (h->slice_type_nos != AV_PICTURE_TYPE_I) {
 146         int list;
 147         for (list = 0; list < h->list_count; list++) {
 148             if (get_bits1(&h->gb)) {
 149                 int index;
 150                 for (index = 0; ; index++) {
 151                     unsigned int reordering_of_pic_nums_idc = get_ue_golomb_31(&h->gb);
 152
 153                     if (reordering_of_pic_nums_idc < 3)
 154                         get_ue_golomb(&h->gb);
 155                     else if (reordering_of_pic_nums_idc > 3) {
 156                         av_log(h->avctx, AV_LOG_ERROR,
 157                                "illegal reordering_of_pic_nums_idc %d\n",
 158                                reordering_of_pic_nums_idc);
 159                         return AVERROR_INVALIDDATA;
 160                     } else
 161                         break;
 162
 163                     if (index >= h->ref_count[list]) {
 164                         av_log(h->avctx, AV_LOG_ERROR,
 165                                "reference count %d overflow\n", index);
 166                         return AVERROR_INVALIDDATA;
 167                     }
 168                 }
 169             }
 170         }
 171     }
 172
 173     if ((h->pps.weighted_pred && h->slice_type_nos == AV_PICTURE_TYPE_P) ||
 174         (h->pps.weighted_bipred_idc == 1 && h->slice_type_nos == AV_PICTURE_TYPE_B))
 175         ff_pred_weight_table(h);
 176
 177     if (get_bits1(&h->gb)) { // adaptive_ref_pic_marking_mode_flag
 178         int i;
 179         for (i = 0; i < MAX_MMCO_COUNT; i++) {
 180             MMCOOpcode opcode = get_ue_golomb_31(&h->gb);
 181             if (opcode > (unsigned) MMCO_LONG) {
 182                 av_log(h->avctx, AV_LOG_ERROR,
 183                        "illegal memory management control operation %d\n",
 184                        opcode);
 185                 return AVERROR_INVALIDDATA;
 186             }
 187             if (opcode == MMCO_END)
 188                return 0;
 189             else if (opcode == MMCO_RESET)
 190                 return 1;
 191
 192             if (opcode == MMCO_SHORT2UNUSED || opcode == MMCO_SHORT2LONG)
 193                 get_ue_golomb(&h->gb);
 194             if (opcode == MMCO_SHORT2LONG || opcode == MMCO_LONG2UNUSED ||
 195                 opcode == MMCO_LONG || opcode == MMCO_SET_MAX_LONG)
 196                 get_ue_golomb_31(&h->gb);
 197         }
 198     }
 199
 200     return 0;
 201 }
 202
 203 /**
 204  * Parse NAL units of found picture and decode some basic information.
 205  *
 206  * @param s parser context.
 207  * @param avctx codec context.
 208  * @param buf buffer with field/frame data.
 209  * @param buf_size size of the buffer.
 210  */
 211 static inline int parse_nal_units(AVCodecParserContext *s,
 212                                   AVCodecContext *avctx,
 213                                   const uint8_t * const buf, int buf_size)
 214 {
 215     H264ParseContext *p = s->priv_data;
 216     H264Context      *h = &p->h;
 217     int buf_index, next_avc;
 218     unsigned int pps_id;
 219     unsigned int slice_type;
 220     int state = -1, got_reset = 0;
 221     const uint8_t *ptr;
 222     int q264 = buf_size >=4 && !memcmp("Q264", buf, 4);
 223     int field_poc[2];
 224
 225     /* set some sane default values */
 226     s->pict_type         = AV_PICTURE_TYPE_I;
 227     s->key_frame         = 0;
 228     s->picture_structure = AV_PICTURE_STRUCTURE_UNKNOWN;
 229
 230     h->avctx = avctx;
 231     ff_h264_reset_sei(h);
 232     h->sei_fpa.frame_packing_arrangement_cancel_flag = -1;
 233
 234     if (!buf_size)
 235         return 0;
 236
 237     buf_index     = 0;
 238     next_avc      = h->is_avc ? 0 : buf_size;
 239     for (;;) {
 240         int src_length, dst_length, consumed, nalsize = 0;
 241
 242         if (buf_index >= next_avc) {
 243             nalsize = get_avc_nalsize(h, buf, buf_size, &buf_index);
 244             if (nalsize < 0)
 245                 break;
 246             next_avc = buf_index + nalsize;
 247         } else {
 248             buf_index = find_start_code(buf, buf_size, buf_index, next_avc);
 249             if (buf_index >= buf_size)
 250                 break;
 251             if (buf_index >= next_avc)
 252                 continue;
 253         }
 254         src_length = next_avc - buf_index;
 255
 256         state = buf[buf_index];
 257         switch (state & 0x1f) {
 258         case NAL_SLICE:
 259         case NAL_IDR_SLICE:
 260             // Do not walk the whole buffer just to decode slice header
 261             if ((state & 0x1f) == NAL_IDR_SLICE || ((state >> 5) & 0x3) == 0) {
 262                 /* IDR or disposable slice
 263                  * No need to decode many bytes because MMCOs shall not be present. */
 264                 if (src_length > 60)
 265                     src_length = 60;
 266             } else {
 267                 /* To decode up to MMCOs */
 268                 if (src_length > 1000)
 269                     src_length = 1000;
 270             }
 271             break;
 272         }
 273         ptr = ff_h264_decode_nal(h, buf + buf_index, &dst_length,
 274                                  &consumed, src_length);
 275         if (!ptr || dst_length < 0)
 276             break;
 277
 278         buf_index += consumed;
 279
 280         init_get_bits(&h->gb, ptr, 8 * dst_length);
 281         switch (h->nal_unit_type) {
 282         case NAL_SPS:
 283             ff_h264_decode_seq_parameter_set(h);
 284             break;
 285         case NAL_PPS:
 286             ff_h264_decode_picture_parameter_set(h, h->gb.size_in_bits);
 287             break;
 288         case NAL_SEI:
 289             ff_h264_decode_sei(h);
 290             break;
 291         case NAL_IDR_SLICE:
 292             s->key_frame = 1;
 293
 294             h->prev_frame_num        = 0;
 295             h->prev_frame_num_offset = 0;
 296             h->prev_poc_msb          =
 297             h->prev_poc_lsb          = 0;
 298         /* fall through */
 299         case NAL_SLICE:
 300             get_ue_golomb_long(&h->gb);  // skip first_mb_in_slice
 301             slice_type   = get_ue_golomb_31(&h->gb);
 302             s->pict_type = golomb_to_pict_type[slice_type % 5];
 303             if (h->sei_recovery_frame_cnt >= 0) {
 304                 /* key frame, since recovery_frame_cnt is set */
 305                 s->key_frame = 1;
 306             }
 307             pps_id = get_ue_golomb(&h->gb);
 308             if (pps_id >= MAX_PPS_COUNT) {
 309                 av_log(h->avctx, AV_LOG_ERROR,
 310                        "pps_id %u out of range\n", pps_id);
 311                 return -1;
 312             }
 313             if (!h->pps_buffers[pps_id]) {
 314                 av_log(h->avctx, AV_LOG_ERROR,
 315                        "non-existing PPS %u referenced\n", pps_id);
 316                 return -1;
 317             }
 318             h->pps = *h->pps_buffers[pps_id];
 319             if (!h->sps_buffers[h->pps.sps_id]) {
 320                 av_log(h->avctx, AV_LOG_ERROR,
 321                        "non-existing SPS %u referenced\n", h->pps.sps_id);
 322                 return -1;
 323             }
 324             h->sps       = *h->sps_buffers[h->pps.sps_id];
 325             h->frame_num = get_bits(&h->gb, h->sps.log2_max_frame_num);
 326
 327             if(h->sps.ref_frame_count <= 1 && h->pps.ref_count[0] <= 1 && s->pict_type == AV_PICTURE_TYPE_I)
 328                 s->key_frame = 1;
 329
 330             s->coded_width  = 16 * h->sps.mb_width;
 331             s->coded_height = 16 * h->sps.mb_height;
 332             s->width        = s->coded_width  - (h->sps.crop_right + h->sps.crop_left);
 333             s->height       = s->coded_height - (h->sps.crop_top   + h->sps.crop_bottom);
 334             if (s->width <= 0 || s->height <= 0) {
 335                 s->width  = s->coded_width;
 336                 s->height = s->coded_height;
 337             }
 338
 339             switch (h->sps.bit_depth_luma) {
 340             case 9:
 341                 if (CHROMA444(h))      s->format = AV_PIX_FMT_YUV444P9;
 342                 else if (CHROMA422(h)) s->format = AV_PIX_FMT_YUV422P9;
 343                 else                   s->format = AV_PIX_FMT_YUV420P9;
 344                 break;
 345             case 10:
 346                 if (CHROMA444(h))      s->format = AV_PIX_FMT_YUV444P10;
 347                 else if (CHROMA422(h)) s->format = AV_PIX_FMT_YUV422P10;
 348                 else                   s->format = AV_PIX_FMT_YUV420P10;
 349                 break;
 350             case 8:
 351                 if (CHROMA444(h))      s->format = AV_PIX_FMT_YUV444P;
 352                 else if (CHROMA422(h)) s->format = AV_PIX_FMT_YUV422P;
 353                 else                   s->format = AV_PIX_FMT_YUV420P;
 354                 break;
 355             default:
 356                 s->format = AV_PIX_FMT_NONE;
 357             }
 358
 359             avctx->profile = ff_h264_get_profile(&h->sps);
 360             avctx->level   = h->sps.level_idc;
 361
 362             if (h->sps.frame_mbs_only_flag) {
 363                 h->picture_structure = PICT_FRAME;
 364             } else {
 365                 if (get_bits1(&h->gb)) { // field_pic_flag
 366                     h->picture_structure = PICT_TOP_FIELD + get_bits1(&h->gb); // bottom_field_flag
 367                 } else {
 368                     h->picture_structure = PICT_FRAME;
 369                 }
 370             }
 371
 372             if (h->nal_unit_type == NAL_IDR_SLICE)
 373                 get_ue_golomb(&h->gb); /* idr_pic_id */
 374             if (h->sps.poc_type == 0) {
 375                 h->poc_lsb = get_bits(&h->gb, h->sps.log2_max_poc_lsb);
 376
 377                 if (h->pps.pic_order_present == 1 &&
 378                     h->picture_structure == PICT_FRAME)
 379                     h->delta_poc_bottom = get_se_golomb(&h->gb);
 380             }
 381
 382             if (h->sps.poc_type == 1 &&
 383                 !h->sps.delta_pic_order_always_zero_flag) {
 384                 h->delta_poc[0] = get_se_golomb(&h->gb);
 385
 386                 if (h->pps.pic_order_present == 1 &&
 387                     h->picture_structure == PICT_FRAME)
 388                     h->delta_poc[1] = get_se_golomb(&h->gb);
 389             }
 390
 391             /* Decode POC of this picture.
 392              * The prev_ values needed for decoding POC of the next picture are not set here. */
 393             field_poc[0] = field_poc[1] = INT_MAX;
 394             ff_init_poc(h, field_poc, &s->output_picture_number);
 395
 396             /* Continue parsing to check if MMCO_RESET is present.
 397              * FIXME: MMCO_RESET could appear in non-first slice.
 398              *        Maybe, we should parse all undisposable non-IDR slice of this
 399              *        picture until encountering MMCO_RESET in a slice of it. */
 400             if (h->nal_ref_idc && h->nal_unit_type != NAL_IDR_SLICE) {
 401                 got_reset = scan_mmco_reset(s);
 402                 if (got_reset < 0)
 403                     return got_reset;
 404             }
 405
 406             /* Set up the prev_ values for decoding POC of the next picture. */
 407             h->prev_frame_num        = got_reset ? 0 : h->frame_num;
 408             h->prev_frame_num_offset = got_reset ? 0 : h->frame_num_offset;
 409             if (h->nal_ref_idc != 0) {
 410                 if (!got_reset) {
 411                     h->prev_poc_msb = h->poc_msb;
 412                     h->prev_poc_lsb = h->poc_lsb;
 413                 } else {
 414                     h->prev_poc_msb = 0;
 415                     h->prev_poc_lsb =
 416                         h->picture_structure == PICT_BOTTOM_FIELD ? 0 : field_poc[0];
 417                 }
 418             }
 419
 420             if (h->sps.pic_struct_present_flag) {
 421                 switch (h->sei_pic_struct) {
 422                 case SEI_PIC_STRUCT_TOP_FIELD:
 423                 case SEI_PIC_STRUCT_BOTTOM_FIELD:
 424                     s->repeat_pict = 0;
 425                     break;
 426                 case SEI_PIC_STRUCT_FRAME:
 427                 case SEI_PIC_STRUCT_TOP_BOTTOM:
 428                 case SEI_PIC_STRUCT_BOTTOM_TOP:
 429                     s->repeat_pict = 1;
 430                     break;
 431                 case SEI_PIC_STRUCT_TOP_BOTTOM_TOP:
 432                 case SEI_PIC_STRUCT_BOTTOM_TOP_BOTTOM:
 433                     s->repeat_pict = 2;
 434                     break;
 435                 case SEI_PIC_STRUCT_FRAME_DOUBLING:
 436                     s->repeat_pict = 3;
 437                     break;
 438                 case SEI_PIC_STRUCT_FRAME_TRIPLING:
 439                     s->repeat_pict = 5;
 440                     break;
 441                 default:
 442                     s->repeat_pict = h->picture_structure == PICT_FRAME ? 1 : 0;
 443                     break;
 444                 }
 445             } else {
 446                 s->repeat_pict = h->picture_structure == PICT_FRAME ? 1 : 0;
 447             }
 448
 449             if (h->picture_structure == PICT_FRAME) {
 450                 s->picture_structure = AV_PICTURE_STRUCTURE_FRAME;
 451                 if (h->sps.pic_struct_present_flag) {
 452                     switch (h->sei_pic_struct) {
 453                     case SEI_PIC_STRUCT_TOP_BOTTOM:
 454                     case SEI_PIC_STRUCT_TOP_BOTTOM_TOP:
 455                         s->field_order = AV_FIELD_TT;
 456                         break;
 457                     case SEI_PIC_STRUCT_BOTTOM_TOP:
 458                     case SEI_PIC_STRUCT_BOTTOM_TOP_BOTTOM:
 459                         s->field_order = AV_FIELD_BB;
 460                         break;
 461                     default:
 462                         s->field_order = AV_FIELD_PROGRESSIVE;
 463                         break;
 464                     }
 465                 } else {
 466                     if (field_poc[0] < field_poc[1])
 467                         s->field_order = AV_FIELD_TT;
 468                     else if (field_poc[0] > field_poc[1])
 469                         s->field_order = AV_FIELD_BB;
 470                     else
 471                         s->field_order = AV_FIELD_PROGRESSIVE;
 472                 }
 473             } else {
 474                 if (h->picture_structure == PICT_TOP_FIELD)
 475                     s->picture_structure = AV_PICTURE_STRUCTURE_TOP_FIELD;
 476                 else
 477                     s->picture_structure = AV_PICTURE_STRUCTURE_BOTTOM_FIELD;
 478                 s->field_order = AV_FIELD_UNKNOWN;
 479             }
 480
 481             return 0; /* no need to evaluate the rest */
 482         }
 483     }
 484     if (q264)
 485         return 0;
 486     /* didn't find a picture! */
 487     av_log(h->avctx, AV_LOG_ERROR, "missing picture in access unit with size %d\n", buf_size);
 488     return -1;
 489 }
 490
 491 static int h264_parse(AVCodecParserContext *s,
 492                       AVCodecContext *avctx,
 493                       const uint8_t **poutbuf, int *poutbuf_size,
 494                       const uint8_t *buf, int buf_size)
 495 {
 496     H264ParseContext *p = s->priv_data;
 497     H264Context      *h = &p->h;
 498     ParseContext *pc = &p->pc;
 499     int next;
 500
 501     if (!p->got_first) {
 502         p->got_first = 1;
 503         if (avctx->extradata_size) {
 504             h->avctx = avctx;
 505             // must be done like in decoder, otherwise opening the parser,
 506             // letting it create extradata and then closing and opening again
 507             // will cause has_b_frames to be always set.
 508             // Note that estimate_timings_from_pts does exactly this.
 509             if (!avctx->has_b_frames)
 510                 h->low_delay = 1;
 511             ff_h264_decode_extradata(h, avctx->extradata, avctx->extradata_size);
 512         }
 513     }
 514
 515     if (s->flags & PARSER_FLAG_COMPLETE_FRAMES) {
 516         next = buf_size;
 517     } else {
 518         next = h264_find_frame_end(p, buf, buf_size);
 519
 520         if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
 521             *poutbuf      = NULL;
 522             *poutbuf_size = 0;
 523             return buf_size;
 524         }
 525
 526         if (next < 0 && next != END_NOT_FOUND) {
 527             av_assert1(pc->last_index + next >= 0);
 528             h264_find_frame_end(p, &pc->buffer[pc->last_index + next], -next); // update state
 529         }
 530     }
 531
 532     parse_nal_units(s, avctx, buf, buf_size);
 533
 534     if (avctx->framerate.num)
 535         avctx->time_base = av_inv_q(av_mul_q(avctx->framerate, (AVRational){avctx->ticks_per_frame, 1}));
 536     if (h->sei_cpb_removal_delay >= 0) {
 537         s->dts_sync_point    = h->sei_buffering_period_present;
 538         s->dts_ref_dts_delta = h->sei_cpb_removal_delay;
 539         s->pts_dts_delta     = h->sei_dpb_output_delay;
 540     } else {
 541         s->dts_sync_point    = INT_MIN;
 542         s->dts_ref_dts_delta = INT_MIN;
 543         s->pts_dts_delta     = INT_MIN;
 544     }
 545
 546     if (s->flags & PARSER_FLAG_ONCE) {
 547         s->flags &= PARSER_FLAG_COMPLETE_FRAMES;
 548     }
 549
 550     *poutbuf      = buf;
 551     *poutbuf_size = buf_size;
 552     return next;
 553 }
 554
 555 static int h264_split(AVCodecContext *avctx,
 556                       const uint8_t *buf, int buf_size)
 557 {
 558     uint32_t state = -1;
 559     int has_sps    = 0;
 560     int has_pps    = 0;
 561     const uint8_t *ptr = buf, *end = buf + buf_size;
 562     int nalu_type;
 563
 564     while (ptr < end) {
 565         ptr = avpriv_find_start_code(ptr, end, &state);
 566         if ((state & 0xFFFFFF00) != 0x100)
 567             break;
 568         nalu_type = state & 0x1F;
 569         if (nalu_type == NAL_SPS) {
 570             has_sps = 1;
 571         } else if (nalu_type == NAL_PPS)
 572             has_pps = 1;
 573         /* else if (nalu_type == 0x01 ||
 574          *     nalu_type == 0x02 ||
 575          *     nalu_type == 0x05) {
 576          *  }
 577          */
 578         else if ((nalu_type != NAL_SEI || has_pps) &&
 579                   nalu_type != NAL_AUD && nalu_type != NAL_SPS_EXT &&
 580                   nalu_type != 0x0f) {
 581             if (has_sps) {
 582                 while (ptr - 4 > buf && ptr[-5] == 0)
 583                     ptr--;
 584                 return ptr - 4 - buf;
 585             }
 586         }
 587     }
 588
 589     return 0;
 590 }
 591
 592 static void h264_close(AVCodecParserContext *s)
 593 {
 594     H264ParseContext *p = s->priv_data;
 595     H264Context      *h = &p->h;
 596     ParseContext *pc = &p->pc;
 597
 598     av_freep(&pc->buffer);
 599     ff_h264_free_context(h);
 600 }
 601
 602 static av_cold int init(AVCodecParserContext *s)
 603 {
 604     H264ParseContext *p = s->priv_data;
 605     H264Context      *h = &p->h;
 606     h->thread_context[0]   = h;
 607     h->slice_context_count = 1;
 608     ff_h264dsp_init(&h->h264dsp, 8, 1);
 609     return 0;
 610 }
 611
 612 AVCodecParser ff_h264_parser = {
 613     .codec_ids      = { AV_CODEC_ID_H264 },
 614     .priv_data_size = sizeof(H264ParseContext),
 615     .parser_init    = init,
 616     .parser_parse   = h264_parse,
 617     .parser_close   = h264_close,
 618     .split          = h264_split,
 619 };