mirror of https://github.com/FFmpeg/FFmpeg.git
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
351 lines
11 KiB
351 lines
11 KiB
/* |
|
* HEVC Annex B format parser |
|
* |
|
* Copyright (C) 2012 - 2013 Guillaume Martres |
|
* |
|
* 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 |
|
*/ |
|
|
|
#include "libavutil/common.h" |
|
|
|
#include "parser.h" |
|
#include "hevc.h" |
|
#include "golomb.h" |
|
|
|
#define START_CODE 0x000001 ///< start_code_prefix_one_3bytes |
|
|
|
typedef struct HEVCParseContext { |
|
HEVCContext h; |
|
ParseContext pc; |
|
} HEVCParseContext; |
|
|
|
/** |
|
* Find the end of the current frame in the bitstream. |
|
* @return the position of the first byte of the next frame, or END_NOT_FOUND |
|
*/ |
|
static int hevc_find_frame_end(AVCodecParserContext *s, const uint8_t *buf, |
|
int buf_size) |
|
{ |
|
int i; |
|
ParseContext *pc = &((HEVCParseContext *)s->priv_data)->pc; |
|
|
|
for (i = 0; i < buf_size; i++) { |
|
int nut; |
|
|
|
pc->state64 = (pc->state64 << 8) | buf[i]; |
|
|
|
if (((pc->state64 >> 3 * 8) & 0xFFFFFF) != START_CODE) |
|
continue; |
|
|
|
nut = (pc->state64 >> 2 * 8 + 1) & 0x3F; |
|
// Beginning of access unit |
|
if ((nut >= NAL_VPS && nut <= NAL_AUD) || nut == NAL_SEI_PREFIX || |
|
(nut >= 41 && nut <= 44) || (nut >= 48 && nut <= 55)) { |
|
if (pc->frame_start_found) { |
|
pc->frame_start_found = 0; |
|
return i - 5; |
|
} |
|
} else if (nut <= NAL_RASL_R || |
|
(nut >= NAL_BLA_W_LP && nut <= NAL_CRA_NUT)) { |
|
int first_slice_segment_in_pic_flag = buf[i] >> 7; |
|
if (first_slice_segment_in_pic_flag) { |
|
if (!pc->frame_start_found) { |
|
pc->frame_start_found = 1; |
|
} else { // First slice of next frame found |
|
pc->frame_start_found = 0; |
|
return i - 5; |
|
} |
|
} |
|
} |
|
} |
|
|
|
return END_NOT_FOUND; |
|
} |
|
|
|
/** |
|
* 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 *buf, int buf_size) |
|
{ |
|
HEVCContext *h = &((HEVCParseContext *)s->priv_data)->h; |
|
GetBitContext *gb = &h->HEVClc->gb; |
|
SliceHeader *sh = &h->sh; |
|
const uint8_t *buf_end = buf + buf_size; |
|
int state = -1, i; |
|
HEVCNAL *nal; |
|
|
|
/* set some sane default values */ |
|
s->pict_type = AV_PICTURE_TYPE_I; |
|
s->key_frame = 0; |
|
s->picture_structure = AV_PICTURE_STRUCTURE_UNKNOWN; |
|
|
|
h->avctx = avctx; |
|
|
|
if (!buf_size) |
|
return 0; |
|
|
|
if (h->nals_allocated < 1) { |
|
HEVCNAL *tmp = av_realloc_array(h->nals, 1, sizeof(*tmp)); |
|
if (!tmp) |
|
return AVERROR(ENOMEM); |
|
h->nals = tmp; |
|
memset(h->nals, 0, sizeof(*tmp)); |
|
h->nals_allocated = 1; |
|
} |
|
|
|
nal = &h->nals[0]; |
|
|
|
for (;;) { |
|
int src_length, consumed; |
|
buf = avpriv_find_start_code(buf, buf_end, &state); |
|
if (--buf + 2 >= buf_end) |
|
break; |
|
src_length = buf_end - buf; |
|
|
|
h->nal_unit_type = (*buf >> 1) & 0x3f; |
|
h->temporal_id = (*(buf + 1) & 0x07) - 1; |
|
if (h->nal_unit_type <= NAL_CRA_NUT) { |
|
// Do not walk the whole buffer just to decode slice segment header |
|
if (src_length > 20) |
|
src_length = 20; |
|
} |
|
|
|
consumed = ff_hevc_extract_rbsp(h, buf, src_length, nal); |
|
if (consumed < 0) |
|
return consumed; |
|
|
|
init_get_bits8(gb, nal->data + 2, nal->size); |
|
switch (h->nal_unit_type) { |
|
case NAL_VPS: |
|
ff_hevc_decode_nal_vps(h); |
|
break; |
|
case NAL_SPS: |
|
ff_hevc_decode_nal_sps(h); |
|
break; |
|
case NAL_PPS: |
|
ff_hevc_decode_nal_pps(h); |
|
break; |
|
case NAL_SEI_PREFIX: |
|
case NAL_SEI_SUFFIX: |
|
ff_hevc_decode_nal_sei(h); |
|
break; |
|
case NAL_TRAIL_N: |
|
case NAL_TRAIL_R: |
|
case NAL_TSA_N: |
|
case NAL_TSA_R: |
|
case NAL_STSA_N: |
|
case NAL_STSA_R: |
|
case NAL_RADL_N: |
|
case NAL_RADL_R: |
|
case NAL_RASL_N: |
|
case NAL_RASL_R: |
|
case NAL_BLA_W_LP: |
|
case NAL_BLA_W_RADL: |
|
case NAL_BLA_N_LP: |
|
case NAL_IDR_W_RADL: |
|
case NAL_IDR_N_LP: |
|
case NAL_CRA_NUT: |
|
sh->first_slice_in_pic_flag = get_bits1(gb); |
|
s->picture_structure = h->picture_struct; |
|
s->field_order = h->picture_struct; |
|
|
|
if (IS_IRAP(h)) { |
|
s->key_frame = 1; |
|
sh->no_output_of_prior_pics_flag = get_bits1(gb); |
|
} |
|
|
|
sh->pps_id = get_ue_golomb(gb); |
|
if (sh->pps_id >= MAX_PPS_COUNT || !h->pps_list[sh->pps_id]) { |
|
av_log(h->avctx, AV_LOG_ERROR, "PPS id out of range: %d\n", sh->pps_id); |
|
return AVERROR_INVALIDDATA; |
|
} |
|
h->pps = (HEVCPPS*)h->pps_list[sh->pps_id]->data; |
|
|
|
if (h->pps->sps_id >= MAX_SPS_COUNT || !h->sps_list[h->pps->sps_id]) { |
|
av_log(h->avctx, AV_LOG_ERROR, "SPS id out of range: %d\n", h->pps->sps_id); |
|
return AVERROR_INVALIDDATA; |
|
} |
|
if (h->sps != (HEVCSPS*)h->sps_list[h->pps->sps_id]->data) { |
|
h->sps = (HEVCSPS*)h->sps_list[h->pps->sps_id]->data; |
|
h->vps = (HEVCVPS*)h->vps_list[h->sps->vps_id]->data; |
|
} |
|
|
|
if (!sh->first_slice_in_pic_flag) { |
|
int slice_address_length; |
|
|
|
if (h->pps->dependent_slice_segments_enabled_flag) |
|
sh->dependent_slice_segment_flag = get_bits1(gb); |
|
else |
|
sh->dependent_slice_segment_flag = 0; |
|
|
|
slice_address_length = av_ceil_log2_c(h->sps->ctb_width * |
|
h->sps->ctb_height); |
|
sh->slice_segment_addr = get_bits(gb, slice_address_length); |
|
if (sh->slice_segment_addr >= h->sps->ctb_width * h->sps->ctb_height) { |
|
av_log(h->avctx, AV_LOG_ERROR, "Invalid slice segment address: %u.\n", |
|
sh->slice_segment_addr); |
|
return AVERROR_INVALIDDATA; |
|
} |
|
} else |
|
sh->dependent_slice_segment_flag = 0; |
|
|
|
if (sh->dependent_slice_segment_flag) |
|
break; |
|
|
|
for (i = 0; i < h->pps->num_extra_slice_header_bits; i++) |
|
skip_bits(gb, 1); // slice_reserved_undetermined_flag[] |
|
|
|
sh->slice_type = get_ue_golomb(gb); |
|
if (!(sh->slice_type == I_SLICE || sh->slice_type == P_SLICE || |
|
sh->slice_type == B_SLICE)) { |
|
av_log(h->avctx, AV_LOG_ERROR, "Unknown slice type: %d.\n", |
|
sh->slice_type); |
|
return AVERROR_INVALIDDATA; |
|
} |
|
s->pict_type = sh->slice_type == B_SLICE ? AV_PICTURE_TYPE_B : |
|
sh->slice_type == P_SLICE ? AV_PICTURE_TYPE_P : |
|
AV_PICTURE_TYPE_I; |
|
|
|
if (h->pps->output_flag_present_flag) |
|
sh->pic_output_flag = get_bits1(gb); |
|
|
|
if (h->sps->separate_colour_plane_flag) |
|
sh->colour_plane_id = get_bits(gb, 2); |
|
|
|
if (!IS_IDR(h)) { |
|
sh->pic_order_cnt_lsb = get_bits(gb, h->sps->log2_max_poc_lsb); |
|
s->output_picture_number = h->poc = ff_hevc_compute_poc(h, sh->pic_order_cnt_lsb); |
|
} else |
|
s->output_picture_number = h->poc = 0; |
|
|
|
if (h->temporal_id == 0 && |
|
h->nal_unit_type != NAL_TRAIL_N && |
|
h->nal_unit_type != NAL_TSA_N && |
|
h->nal_unit_type != NAL_STSA_N && |
|
h->nal_unit_type != NAL_RADL_N && |
|
h->nal_unit_type != NAL_RASL_N && |
|
h->nal_unit_type != NAL_RADL_R && |
|
h->nal_unit_type != NAL_RASL_R) |
|
h->pocTid0 = h->poc; |
|
|
|
return 0; /* no need to evaluate the rest */ |
|
} |
|
buf += consumed; |
|
} |
|
/* didn't find a picture! */ |
|
av_log(h->avctx, AV_LOG_ERROR, "missing picture in access unit\n"); |
|
return -1; |
|
} |
|
|
|
static int hevc_parse(AVCodecParserContext *s, |
|
AVCodecContext *avctx, |
|
const uint8_t **poutbuf, int *poutbuf_size, |
|
const uint8_t *buf, int buf_size) |
|
{ |
|
int next; |
|
ParseContext *pc = &((HEVCParseContext *)s->priv_data)->pc; |
|
|
|
if (s->flags & PARSER_FLAG_COMPLETE_FRAMES) { |
|
next = buf_size; |
|
} else { |
|
next = hevc_find_frame_end(s, buf, buf_size); |
|
if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) { |
|
*poutbuf = NULL; |
|
*poutbuf_size = 0; |
|
return buf_size; |
|
} |
|
} |
|
|
|
parse_nal_units(s, avctx, buf, buf_size); |
|
|
|
*poutbuf = buf; |
|
*poutbuf_size = buf_size; |
|
return next; |
|
} |
|
|
|
// Split after the parameter sets at the beginning of the stream if they exist. |
|
static int hevc_split(AVCodecContext *avctx, const uint8_t *buf, int buf_size) |
|
{ |
|
const uint8_t *ptr = buf, *end = buf + buf_size; |
|
uint32_t state = -1; |
|
int has_ps = 0, nut; |
|
|
|
while (ptr < end) { |
|
ptr = avpriv_find_start_code(ptr, end, &state); |
|
if ((state >> 8) != START_CODE) |
|
break; |
|
nut = (state >> 1) & 0x3F; |
|
if (nut >= NAL_VPS && nut <= NAL_PPS) |
|
has_ps = 1; |
|
else if (has_ps) |
|
return ptr - 4 - buf; |
|
else // no parameter set at the beginning of the stream |
|
return 0; |
|
} |
|
return 0; |
|
} |
|
|
|
static int hevc_init(AVCodecParserContext *s) |
|
{ |
|
HEVCContext *h = &((HEVCParseContext *)s->priv_data)->h; |
|
h->HEVClc = av_mallocz(sizeof(HEVCLocalContext)); |
|
if (!h->HEVClc) |
|
return AVERROR(ENOMEM); |
|
h->skipped_bytes_pos_size = INT_MAX; |
|
|
|
return 0; |
|
} |
|
|
|
static void hevc_close(AVCodecParserContext *s) |
|
{ |
|
int i; |
|
HEVCContext *h = &((HEVCParseContext *)s->priv_data)->h; |
|
ParseContext *pc = &((HEVCParseContext *)s->priv_data)->pc; |
|
|
|
av_freep(&h->skipped_bytes_pos); |
|
av_freep(&h->HEVClc); |
|
av_freep(&pc->buffer); |
|
|
|
for (i = 0; i < FF_ARRAY_ELEMS(h->vps_list); i++) |
|
av_buffer_unref(&h->vps_list[i]); |
|
for (i = 0; i < FF_ARRAY_ELEMS(h->sps_list); i++) |
|
av_buffer_unref(&h->sps_list[i]); |
|
for (i = 0; i < FF_ARRAY_ELEMS(h->pps_list); i++) |
|
av_buffer_unref(&h->pps_list[i]); |
|
|
|
h->sps = NULL; |
|
|
|
for (i = 0; i < h->nals_allocated; i++) |
|
av_freep(&h->nals[i].rbsp_buffer); |
|
av_freep(&h->nals); |
|
h->nals_allocated = 0; |
|
} |
|
|
|
AVCodecParser ff_hevc_parser = { |
|
.codec_ids = { AV_CODEC_ID_HEVC }, |
|
.priv_data_size = sizeof(HEVCParseContext), |
|
.parser_init = hevc_init, |
|
.parser_parse = hevc_parse, |
|
.parser_close = hevc_close, |
|
.split = hevc_split, |
|
};
|
|
|