1 /*
2 * iLBC storage file format
3 * Copyright (c) 2012 Martin Storsjo
4 *
5 * This file is part of FFmpeg.
6 *
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.
11 *
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.
16 *
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
20 */
21
22 #include "avformat.h"
23 #include "internal.h"
24 #include "rawenc.h"
25
26 static const char mode20_header[] = "#!iLBC20\n";
27 static const char mode30_header[] = "#!iLBC30\n";
28
ilbc_write_header(AVFormatContext * s)29 static int ilbc_write_header(AVFormatContext *s)
30 {
31 AVIOContext *pb = s->pb;
32 AVCodecParameters *par;
33
34 if (s->nb_streams != 1) {
35 av_log(s, AV_LOG_ERROR, "Unsupported number of streams\n");
36 return AVERROR(EINVAL);
37 }
38 par = s->streams[0]->codecpar;
39
40 if (par->codec_id != AV_CODEC_ID_ILBC) {
41 av_log(s, AV_LOG_ERROR, "Unsupported codec\n");
42 return AVERROR(EINVAL);
43 }
44
45 if (par->block_align == 50) {
46 avio_write(pb, mode30_header, sizeof(mode30_header) - 1);
47 } else if (par->block_align == 38) {
48 avio_write(pb, mode20_header, sizeof(mode20_header) - 1);
49 } else {
50 av_log(s, AV_LOG_ERROR, "Unsupported mode\n");
51 return AVERROR(EINVAL);
52 }
53 return 0;
54 }
55
ilbc_probe(const AVProbeData * p)56 static int ilbc_probe(const AVProbeData *p)
57 {
58 // Only check for "#!iLBC" which matches both formats
59 if (!memcmp(p->buf, mode20_header, 6))
60 return AVPROBE_SCORE_MAX;
61 else
62 return 0;
63 }
64
ilbc_read_header(AVFormatContext * s)65 static int ilbc_read_header(AVFormatContext *s)
66 {
67 AVIOContext *pb = s->pb;
68 AVStream *st;
69 uint8_t header[9];
70
71 avio_read(pb, header, 9);
72
73 st = avformat_new_stream(s, NULL);
74 if (!st)
75 return AVERROR(ENOMEM);
76 st->codecpar->codec_id = AV_CODEC_ID_ILBC;
77 st->codecpar->sample_rate = 8000;
78 st->codecpar->channels = 1;
79 st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
80 st->start_time = 0;
81 avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
82 if (!memcmp(header, mode20_header, sizeof(mode20_header) - 1)) {
83 st->codecpar->block_align = 38;
84 st->codecpar->bit_rate = 15200;
85 } else if (!memcmp(header, mode30_header, sizeof(mode30_header) - 1)) {
86 st->codecpar->block_align = 50;
87 st->codecpar->bit_rate = 13333;
88 } else {
89 av_log(s, AV_LOG_ERROR, "Unrecognized iLBC file header\n");
90 return AVERROR_INVALIDDATA;
91 }
92
93 return 0;
94 }
95
ilbc_read_packet(AVFormatContext * s,AVPacket * pkt)96 static int ilbc_read_packet(AVFormatContext *s,
97 AVPacket *pkt)
98 {
99 AVCodecParameters *par = s->streams[0]->codecpar;
100 int ret;
101
102 if ((ret = av_new_packet(pkt, par->block_align)) < 0)
103 return ret;
104
105 pkt->stream_index = 0;
106 pkt->pos = avio_tell(s->pb);
107 pkt->duration = par->block_align == 38 ? 160 : 240;
108 if ((ret = avio_read(s->pb, pkt->data, par->block_align)) != par->block_align) {
109 return ret < 0 ? ret : AVERROR(EIO);
110 }
111
112 return 0;
113 }
114
115 AVInputFormat ff_ilbc_demuxer = {
116 .name = "ilbc",
117 .long_name = NULL_IF_CONFIG_SMALL("iLBC storage"),
118 .read_probe = ilbc_probe,
119 .read_header = ilbc_read_header,
120 .read_packet = ilbc_read_packet,
121 .flags = AVFMT_GENERIC_INDEX,
122 };
123
124 #if CONFIG_ILBC_MUXER
125 AVOutputFormat ff_ilbc_muxer = {
126 .name = "ilbc",
127 .long_name = NULL_IF_CONFIG_SMALL("iLBC storage"),
128 .mime_type = "audio/iLBC",
129 .extensions = "lbc",
130 .audio_codec = AV_CODEC_ID_ILBC,
131 .write_header = ilbc_write_header,
132 .write_packet = ff_raw_write_packet,
133 .flags = AVFMT_NOTIMESTAMPS,
134 };
135 #endif
136