/*
  * H.26L/H.264/AVC/JVT/14496-10/... parser
  * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
  *
  * 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 <michaelni@gmx.at>
  */
 

 #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 "get_bits.h"

 #include "golomb.h"

 #include "h264.h"

 #include "h264_sei.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;

 } 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 == NAL_SEI || nalu_type == NAL_SPS ||
                 nalu_type == NAL_PPS || nalu_type == NAL_AUD) {

                 if (pc->frame_start_found) {

                     i++;

                     goto found;

                 }

             } else if (nalu_type == NAL_SLICE || nalu_type == NAL_DPA ||
                        nalu_type == NAL_IDR_SLICE) {

                 state += 8;

                 continue;
             }

             state = 7;
         } else {

             p->parse_history[p->parse_history_count++] = buf[i];
             if (p->parse_history_count > 5) {
                 unsigned int mb, last_mb = p->parse_last_mb;

                 GetBitContext gb;
 

                 init_get_bits(&gb, p->parse_history, 8*p->parse_history_count);
                 p->parse_history_count = 0;

                 mb= get_ue_golomb_long(&gb);

                 p->parse_last_mb = mb;

                 if (pc->frame_start_found) {

                     if (mb <= last_mb)

                         goto found;

                 } else

                     pc->frame_start_found = 1;

                 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) - 5 * (state > 7);

 }
 

 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, 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;
 }
 

 static inline int get_avc_nalsize(H264ParseContext *p, const uint8_t *buf,
                                   int buf_size, int *buf_index, void *logctx)
 {
     int i, nalsize = 0;
 
     if (*buf_index >= buf_size - p->nal_length_size) {
         // the end of the buffer is reached, refill it
         return AVERROR(EAGAIN);
     }
 
     for (i = 0; i < p->nal_length_size; i++)
         nalsize = ((unsigned)nalsize << 8) | buf[(*buf_index)++];
     if (nalsize <= 0 || nalsize > buf_size - *buf_index) {
         av_log(logctx, AV_LOG_ERROR,
                "AVC: nal size %d\n", nalsize);
         return AVERROR_INVALIDDATA;
     }
     return nalsize;
 }
 

 /**

  * 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;

     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.frame_packing_arrangement_cancel_flag = -1;

     if (!buf_size)
         return 0;
 

     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_avc_nalsize(p, 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 NAL_SLICE:
         case NAL_IDR_SLICE:
             // Do not walk the whole buffer just to decode slice header

             if ((state & 0x1f) == 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, &nal);

         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 NAL_SPS:

             ff_h264_decode_seq_parameter_set(&nal.gb, avctx, &p->ps, 0);

             break;
         case NAL_PPS:

             ff_h264_decode_picture_parameter_set(&nal.gb, avctx, &p->ps,
                                                  nal.size_bits);

             break;
         case NAL_SEI:

             ff_h264_sei_decode(&p->sei, &nal.gb, &p->ps, avctx);

             break;
         case 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 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);
             av_buffer_unref(&p->ps.sps_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;
 

             if (!p->ps.sps_list[p->ps.pps->sps_id]) {

                 av_log(avctx, AV_LOG_ERROR,

                        "non-existing SPS %u referenced\n", p->ps.pps->sps_id);

                 goto fail;

             }

 
             p->ps.sps_ref = av_buffer_ref(p->ps.sps_list[p->ps.pps->sps_id]);
             if (!p->ps.sps_ref)
                 goto fail;
             p->ps.sps = (SPS*)p->ps.sps_ref->data;

             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 == 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;

             ff_h264_init_poc(field_poc, &s->output_picture_number, sps,

                              &p->poc, p->picture_structure, nal.ref_idc);

             /* 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 != 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 (sps->pic_struct_present_flag) {

                 switch (p->sei.picture_timing.pic_struct) {

                 case SEI_PIC_STRUCT_TOP_FIELD:
                 case SEI_PIC_STRUCT_BOTTOM_FIELD:
                     s->repeat_pict = 0;
                     break;
                 case SEI_PIC_STRUCT_FRAME:
                 case SEI_PIC_STRUCT_TOP_BOTTOM:
                 case SEI_PIC_STRUCT_BOTTOM_TOP:
                     s->repeat_pict = 1;
                     break;
                 case SEI_PIC_STRUCT_TOP_BOTTOM_TOP:
                 case SEI_PIC_STRUCT_BOTTOM_TOP_BOTTOM:
                     s->repeat_pict = 2;
                     break;
                 case SEI_PIC_STRUCT_FRAME_DOUBLING:
                     s->repeat_pict = 3;
                     break;
                 case 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) {

                     switch (p->sei.picture_timing.pic_struct) {

                     case SEI_PIC_STRUCT_TOP_BOTTOM:
                     case SEI_PIC_STRUCT_TOP_BOTTOM_TOP:
                         s->field_order = AV_FIELD_TT;
                         break;
                     case SEI_PIC_STRUCT_BOTTOM_TOP:
                     case 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;
                 s->field_order = AV_FIELD_UNKNOWN;
             }
 

             av_freep(&nal.rbsp_buffer);

             return 0; /* no need to evaluate the rest */
         }
     }

     if (q264) {
         av_freep(&nal.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(&nal.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;
     }

     *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 == NAL_SPS) {

             has_sps = 1;

         } else if (nalu_type == NAL_PPS)

             has_pps = 1;

         /* else if (nalu_type == 0x01 ||
          *     nalu_type == 0x02 ||
          *     nalu_type == 0x05) {

          *  }
          */

         else if ((nalu_type != NAL_SEI || has_pps) &&
                   nalu_type != NAL_AUD && nalu_type != 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;

     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,

 };