1/* 2 * Audio and Video frame extraction 3 * Copyright (c) 2003 Fabrice Bellard 4 * Copyright (c) 2003 Michael Niedermayer 5 * 6 * This file is part of Libav. 7 * 8 * Libav is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU Lesser General Public 10 * License as published by the Free Software Foundation; either 11 * version 2.1 of the License, or (at your option) any later version. 12 * 13 * Libav is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 16 * Lesser General Public License for more details. 17 * 18 * You should have received a copy of the GNU Lesser General Public 19 * License along with Libav; if not, write to the Free Software 20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 21 */ 22 23#include "parser.h" 24#include "aac_ac3_parser.h" 25#include "aacadtsdec.h" 26#include "get_bits.h" 27#include "mpeg4audio.h" 28 29static int aac_sync(uint64_t state, AACAC3ParseContext *hdr_info, 30 int *need_next_header, int *new_frame_start) 31{ 32 GetBitContext bits; 33 AACADTSHeaderInfo hdr; 34 int size; 35 union { 36 uint64_t u64; 37 uint8_t u8[8]; 38 } tmp; 39 40 tmp.u64 = av_be2ne64(state); 41 init_get_bits(&bits, tmp.u8+8-AAC_ADTS_HEADER_SIZE, AAC_ADTS_HEADER_SIZE * 8); 42 43 if ((size = avpriv_aac_parse_header(&bits, &hdr)) < 0) 44 return 0; 45 *need_next_header = 0; 46 *new_frame_start = 1; 47 hdr_info->sample_rate = hdr.sample_rate; 48 hdr_info->channels = ff_mpeg4audio_channels[hdr.chan_config]; 49 hdr_info->samples = hdr.samples; 50 hdr_info->bit_rate = hdr.bit_rate; 51 return size; 52} 53 54static av_cold int aac_parse_init(AVCodecParserContext *s1) 55{ 56 AACAC3ParseContext *s = s1->priv_data; 57 s->header_size = AAC_ADTS_HEADER_SIZE; 58 s->sync = aac_sync; 59 return 0; 60} 61 62 63AVCodecParser ff_aac_parser = { 64 .codec_ids = { CODEC_ID_AAC }, 65 .priv_data_size = sizeof(AACAC3ParseContext), 66 .parser_init = aac_parse_init, 67 .parser_parse = ff_aac_ac3_parse, 68 .parser_close = ff_parse_close, 69}; 70