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 FFmpeg.
7 *
8 * FFmpeg 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 * FFmpeg 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 FFmpeg; 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 "adts_header.h"
26#include "adts_parser.h"
27#include "get_bits.h"
28#include "mpeg4audio.h"
29
30static int aac_sync(uint64_t state, AACAC3ParseContext *hdr_info,
31        int *need_next_header, int *new_frame_start)
32{
33    GetBitContext bits;
34    AACADTSHeaderInfo hdr;
35    int size;
36    union {
37        uint64_t u64;
38        uint8_t  u8[8 + AV_INPUT_BUFFER_PADDING_SIZE];
39    } tmp;
40
41    tmp.u64 = av_be2ne64(state);
42    init_get_bits(&bits, tmp.u8 + 8 - AV_AAC_ADTS_HEADER_SIZE,
43                  AV_AAC_ADTS_HEADER_SIZE * 8);
44
45    if ((size = ff_adts_header_parse(&bits, &hdr)) < 0)
46        return 0;
47    *need_next_header = 0;
48    *new_frame_start  = 1;
49    hdr_info->sample_rate = hdr.sample_rate;
50    hdr_info->channels    = ff_mpeg4audio_channels[hdr.chan_config];
51    hdr_info->samples     = hdr.samples;
52    hdr_info->bit_rate    = hdr.bit_rate;
53    return size;
54}
55
56static av_cold int aac_parse_init(AVCodecParserContext *s1)
57{
58    AACAC3ParseContext *s = s1->priv_data;
59    s->header_size = AV_AAC_ADTS_HEADER_SIZE;
60    s->sync = aac_sync;
61    return 0;
62}
63
64
65const AVCodecParser ff_aac_parser = {
66    .codec_ids      = { AV_CODEC_ID_AAC },
67    .priv_data_size = sizeof(AACAC3ParseContext),
68    .parser_init    = aac_parse_init,
69    .parser_parse   = ff_aac_ac3_parse,
70    .parser_close   = ff_parse_close,
71};
72