change of aac_ac3_parser, so it is able to send complete portion of data to decoder
[ffmpeg.git] / libavcodec / aac_parser.c
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 "bitstream.h"
26 #include "mpeg4audio.h"
27
28 #define AAC_HEADER_SIZE 7
29
30 static int aac_sync(uint64_t state, AACAC3ParseContext *hdr_info,
31         int *need_next_header, int *new_frame_start)
32 {
33     GetBitContext bits;
34     int size, rdb, ch, sr;
35     uint64_t tmp = be2me_64(state);
36
37     init_get_bits(&bits, (uint8_t *)&tmp, AAC_HEADER_SIZE * 8);
38
39     if(get_bits(&bits, 12) != 0xfff)
40         return 0;
41
42     skip_bits1(&bits);          /* id */
43     skip_bits(&bits, 2);        /* layer */
44     skip_bits1(&bits);          /* protection_absent */
45     skip_bits(&bits, 2);        /* profile_objecttype */
46     sr = get_bits(&bits, 4);    /* sample_frequency_index */
47     if(!ff_mpeg4audio_sample_rates[sr])
48         return 0;
49     skip_bits1(&bits);          /* private_bit */
50     ch = get_bits(&bits, 3);    /* channel_configuration */
51     if(!ff_mpeg4audio_channels[ch])
52         return 0;
53     skip_bits1(&bits);          /* original/copy */
54     skip_bits1(&bits);          /* home */
55
56     /* adts_variable_header */
57     skip_bits1(&bits);          /* copyright_identification_bit */
58     skip_bits1(&bits);          /* copyright_identification_start */
59     size = get_bits(&bits, 13); /* aac_frame_length */
60     if(size < AAC_HEADER_SIZE)
61         return 0;
62
63     skip_bits(&bits, 11);       /* adts_buffer_fullness */
64     rdb = get_bits(&bits, 2);   /* number_of_raw_data_blocks_in_frame */
65
66     hdr_info->channels = ff_mpeg4audio_channels[ch];
67     hdr_info->sample_rate = ff_mpeg4audio_sample_rates[sr];
68     hdr_info->samples = (rdb + 1) * 1024;
69     hdr_info->bit_rate = size * 8 * hdr_info->sample_rate / hdr_info->samples;
70
71     *need_next_header=0;
72     *new_frame_start=1;
73     return size;
74 }
75
76 static av_cold int aac_parse_init(AVCodecParserContext *s1)
77 {
78     AACAC3ParseContext *s = s1->priv_data;
79     s->header_size = AAC_HEADER_SIZE;
80     s->sync = aac_sync;
81     return 0;
82 }
83
84
85 AVCodecParser aac_parser = {
86     { CODEC_ID_AAC },
87     sizeof(AACAC3ParseContext),
88     aac_parse_init,
89     ff_aac_ac3_parse,
90     NULL,
91 };