2 * iLBC storage file format
3 * Copyright (c) 2012 Martin Storsjo
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
25 static const char mode20_header
[] = "#!iLBC20\n";
26 static const char mode30_header
[] = "#!iLBC30\n";
28 static int ilbc_write_header(AVFormatContext
*s
)
30 AVIOContext
*pb
= s
->pb
;
33 if (s
->nb_streams
!= 1) {
34 av_log(s
, AV_LOG_ERROR
, "Unsupported number of streams\n");
35 return AVERROR(EINVAL
);
37 enc
= s
->streams
[0]->codec
;
39 if (enc
->codec_id
!= AV_CODEC_ID_ILBC
) {
40 av_log(s
, AV_LOG_ERROR
, "Unsupported codec\n");
41 return AVERROR(EINVAL
);
44 if (enc
->block_align
== 50) {
45 avio_write(pb
, mode30_header
, sizeof(mode30_header
) - 1);
46 } else if (enc
->block_align
== 38) {
47 avio_write(pb
, mode20_header
, sizeof(mode20_header
) - 1);
49 av_log(s
, AV_LOG_ERROR
, "Unsupported mode\n");
50 return AVERROR(EINVAL
);
56 static int ilbc_write_packet(AVFormatContext
*s
, AVPacket
*pkt
)
58 avio_write(s
->pb
, pkt
->data
, pkt
->size
);
62 static int ilbc_probe(AVProbeData
*p
)
64 // Only check for "#!iLBC" which matches both formats
65 if (!memcmp(p
->buf
, mode20_header
, 6))
66 return AVPROBE_SCORE_MAX
;
71 static int ilbc_read_header(AVFormatContext
*s
)
73 AVIOContext
*pb
= s
->pb
;
77 avio_read(pb
, header
, 9);
79 st
= avformat_new_stream(s
, NULL
);
81 return AVERROR(ENOMEM
);
82 st
->codec
->codec_id
= AV_CODEC_ID_ILBC
;
83 st
->codec
->sample_rate
= 8000;
84 st
->codec
->channels
= 1;
85 st
->codec
->codec_type
= AVMEDIA_TYPE_AUDIO
;
87 avpriv_set_pts_info(st
, 64, 1, st
->codec
->sample_rate
);
88 if (!memcmp(header
, mode20_header
, sizeof(mode20_header
) - 1)) {
89 st
->codec
->block_align
= 38;
90 st
->codec
->bit_rate
= 15200;
91 } else if (!memcmp(header
, mode30_header
, sizeof(mode30_header
) - 1)) {
92 st
->codec
->block_align
= 50;
93 st
->codec
->bit_rate
= 13333;
95 av_log(s
, AV_LOG_ERROR
, "Unrecognized iLBC file header\n");
96 return AVERROR_INVALIDDATA
;
102 static int ilbc_read_packet(AVFormatContext
*s
,
105 AVCodecContext
*enc
= s
->streams
[0]->codec
;
108 if ((ret
= av_new_packet(pkt
, enc
->block_align
)) < 0)
111 pkt
->stream_index
= 0;
112 pkt
->pos
= avio_tell(s
->pb
);
113 pkt
->duration
= enc
->block_align
== 38 ? 160 : 240;
114 if ((ret
= avio_read(s
->pb
, pkt
->data
, enc
->block_align
)) != enc
->block_align
) {
116 return ret
< 0 ? ret
: AVERROR(EIO
);
122 AVInputFormat ff_ilbc_demuxer
= {
124 .long_name
= NULL_IF_CONFIG_SMALL("iLBC storage"),
125 .read_probe
= ilbc_probe
,
126 .read_header
= ilbc_read_header
,
127 .read_packet
= ilbc_read_packet
,
128 .flags
= AVFMT_GENERIC_INDEX
,
131 AVOutputFormat ff_ilbc_muxer
= {
133 .long_name
= NULL_IF_CONFIG_SMALL("iLBC storage"),
134 .mime_type
= "audio/iLBC",
136 .audio_codec
= AV_CODEC_ID_ILBC
,
137 .write_header
= ilbc_write_header
,
138 .write_packet
= ilbc_write_packet
,
139 .flags
= AVFMT_NOTIMESTAMPS
,