/* * HEVC Annex B format parser * * Copyright (C) 2012 - 2013 Guillaume Martres * * This file is part of Libav. * * Libav 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. * * Libav 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 Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include "libavutil/common.h" #include "golomb.h" #include "hevc.h" #include "h2645_parse.h" #include "parser.h" #define START_CODE 0x000001 ///< start_code_prefix_one_3bytes #define IS_IRAP_NAL(nal) (nal->type >= 16 && nal->type <= 23) typedef struct HEVCParserContext { ParseContext pc; H2645Packet pkt; HEVCParamSets ps; int parsed_extradata; } HEVCParserContext; static int hevc_parse_slice_header(AVCodecParserContext *s, H2645NAL *nal, AVCodecContext *avctx) { HEVCParserContext *ctx = s->priv_data; GetBitContext *gb = &nal->gb; HEVCPPS *pps; HEVCSPS *sps; unsigned int pps_id; get_bits1(gb); // first slice in pic if (IS_IRAP_NAL(nal)) get_bits1(gb); // no output of prior pics pps_id = get_ue_golomb_long(gb); if (pps_id >= MAX_PPS_COUNT || !ctx->ps.pps_list[pps_id]) { av_log(avctx, AV_LOG_ERROR, "PPS id out of range: %d\n", pps_id); return AVERROR_INVALIDDATA; } pps = (HEVCPPS*)ctx->ps.pps_list[pps_id]->data; sps = (HEVCSPS*)ctx->ps.sps_list[pps->sps_id]->data; /* export the stream parameters */ s->coded_width = sps->width; s->coded_height = sps->height; s->width = sps->output_width; s->height = sps->output_height; s->format = sps->pix_fmt; avctx->profile = sps->ptl.general_ptl.profile_idc; avctx->level = sps->ptl.general_ptl.level_idc; /* ignore the rest for now*/ return 0; } static int parse_nal_units(AVCodecParserContext *s, const uint8_t *buf, int buf_size, AVCodecContext *avctx) { HEVCParserContext *ctx = s->priv_data; int ret, i; ret = ff_h2645_packet_split(&ctx->pkt, buf, buf_size, avctx, 0, 0, AV_CODEC_ID_HEVC); if (ret < 0) return ret; for (i = 0; i < ctx->pkt.nb_nals; i++) { H2645NAL *nal = &ctx->pkt.nals[i]; /* ignore everything except parameter sets and VCL NALUs */ switch (nal->type) { case NAL_VPS: ff_hevc_decode_nal_vps(&nal->gb, avctx, &ctx->ps); break; case NAL_SPS: ff_hevc_decode_nal_sps(&nal->gb, avctx, &ctx->ps, 1); break; case NAL_PPS: ff_hevc_decode_nal_pps(&nal->gb, avctx, &ctx->ps); break; case NAL_TRAIL_R: case NAL_TRAIL_N: case NAL_TSA_N: case NAL_TSA_R: case NAL_STSA_N: case NAL_STSA_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: case NAL_RADL_N: case NAL_RADL_R: case NAL_RASL_N: case NAL_RASL_R: hevc_parse_slice_header(s, nal, avctx); break; } } return 0; } /** * 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) { HEVCParserContext *ctx = s->priv_data; ParseContext *pc = &ctx->pc; int i; 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; s->key_frame = nut >= NAL_BLA_W_LP && nut <= NAL_CRA_NUT; } else { // First slice of next frame found pc->frame_start_found = 0; return i - 5; } } } } return END_NOT_FOUND; } static int hevc_parse(AVCodecParserContext *s, AVCodecContext *avctx, const uint8_t **poutbuf, int *poutbuf_size, const uint8_t *buf, int buf_size) { int next; HEVCParserContext *ctx = s->priv_data; ParseContext *pc = &ctx->pc; if (avctx->extradata && !ctx->parsed_extradata) { parse_nal_units(s, avctx->extradata, avctx->extradata_size, avctx); ctx->parsed_extradata = 1; } 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, buf, buf_size, avctx); *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 void hevc_parser_close(AVCodecParserContext *s) { HEVCParserContext *ctx = s->priv_data; int i; for (i = 0; i < FF_ARRAY_ELEMS(ctx->ps.vps_list); i++) av_buffer_unref(&ctx->ps.vps_list[i]); for (i = 0; i < FF_ARRAY_ELEMS(ctx->ps.sps_list); i++) av_buffer_unref(&ctx->ps.sps_list[i]); for (i = 0; i < FF_ARRAY_ELEMS(ctx->ps.pps_list); i++) av_buffer_unref(&ctx->ps.pps_list[i]); ff_h2645_packet_uninit(&ctx->pkt); av_freep(&ctx->pc.buffer); } AVCodecParser ff_hevc_parser = { .codec_ids = { AV_CODEC_ID_HEVC }, .priv_data_size = sizeof(HEVCParserContext), .parser_parse = hevc_parse, .parser_close = hevc_parser_close, .split = hevc_split, };