3 * Copyright (c) 2003 Fabrice Bellard
4 * Copyright (c) 2003 Michael Niedermayer
6 * This file is part of Libav.
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.
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.
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
24 #include "mpegaudiodecheader.h"
25 #include "libavutil/common.h"
28 typedef struct MpegAudioParseContext
{
33 } MpegAudioParseContext
;
35 #define MPA_HEADER_SIZE 4
37 /* header + layer + bitrate + freq + lsf/mpeg25 */
38 #define SAME_HEADER_MASK \
39 (0xffe00000 | (3 << 17) | (3 << 10) | (3 << 19))
41 static int mpegaudio_parse(AVCodecParserContext
*s1
,
42 AVCodecContext
*avctx
,
43 const uint8_t **poutbuf
, int *poutbuf_size
,
44 const uint8_t *buf
, int buf_size
)
46 MpegAudioParseContext
*s
= s1
->priv_data
;
47 ParseContext
*pc
= &s
->pc
;
48 uint32_t state
= pc
->state
;
50 int next
= END_NOT_FOUND
;
52 for(i
=0; i
<buf_size
; ){
54 int inc
= FFMIN(buf_size
- i
, s
->frame_size
);
64 int ret
, sr
, channels
, bit_rate
, frame_size
;
66 state
= (state
<<8) + buf
[i
++];
68 ret
= avpriv_mpa_decode_header(avctx
, state
, &sr
, &channels
, &frame_size
, &bit_rate
);
73 if((state
&SAME_HEADER_MASK
) != (s
->header
&SAME_HEADER_MASK
) && s
->header
)
77 s
->frame_size
= ret
-4;
79 if (s
->header_count
> 0) {
80 avctx
->sample_rate
= sr
;
81 avctx
->channels
= channels
;
82 s1
->duration
= frame_size
;
83 avctx
->bit_rate
= bit_rate
;
92 if (ff_combine_frame(pc
, next
, &buf
, &buf_size
) < 0) {
99 *poutbuf_size
= buf_size
;
104 AVCodecParser ff_mpegaudio_parser
= {
105 .codec_ids
= { AV_CODEC_ID_MP1
, AV_CODEC_ID_MP2
, AV_CODEC_ID_MP3
},
106 .priv_data_size
= sizeof(MpegAudioParseContext
),
107 .parser_parse
= mpegaudio_parse
,
108 .parser_close
= ff_parse_close
,