| /* |
| * 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) |
| { |
| int i; |
| uint32_t state = -1; |
| int has_ps = 0; |
| |
| for (i = 0; i < buf_size; i++) { |
| state = (state << 8) | buf[i]; |
| if (((state >> 8) & 0xFFFFFF) == START_CODE) { |
| int nut = (state >> 1) & 0x3F; |
| if (nut >= NAL_VPS && nut <= NAL_PPS) |
| has_ps = 1; |
| else if (has_ps) |
| return i - 3; |
| 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)); |
| 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]); |
| |
| av_buffer_unref(&h->current_sps); |
| 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, |
| }; |