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/*
* iLBC storage file format
* Copyright (c) 2012 Martin Storsjo
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "avformat.h"
#include "internal.h"
static const char mode20_header[] = "#!iLBC20\n";
static const char mode30_header[] = "#!iLBC30\n";
static int ilbc_write_header(AVFormatContext *s)
{
AVIOContext *pb = s->pb;
AVCodecContext *enc;
if (s->nb_streams != 1) {
av_log(s, AV_LOG_ERROR, "Unsupported number of streams\n");
return AVERROR(EINVAL);
}
enc = s->streams[0]->codec;
if (enc->codec_id != AV_CODEC_ID_ILBC) {
av_log(s, AV_LOG_ERROR, "Unsupported codec\n");
return AVERROR(EINVAL);
}
if (enc->block_align == 50) {
avio_write(pb, mode30_header, sizeof(mode30_header) - 1);
} else if (enc->block_align == 38) {
avio_write(pb, mode20_header, sizeof(mode20_header) - 1);
} else {
av_log(s, AV_LOG_ERROR, "Unsupported mode\n");
return AVERROR(EINVAL);
}
avio_flush(pb);
return 0;
}
static int ilbc_write_packet(AVFormatContext *s, AVPacket *pkt)
{
avio_write(s->pb, pkt->data, pkt->size);
avio_flush(s->pb);
return 0;
}
static int ilbc_probe(AVProbeData *p)
{
// Only check for "#!iLBC" which matches both formats
if (!memcmp(p->buf, mode20_header, 6))
return AVPROBE_SCORE_MAX;
else
return 0;
}
static int ilbc_read_header(AVFormatContext *s)
{
AVIOContext *pb = s->pb;
AVStream *st;
uint8_t header[9];
avio_read(pb, header, 9);
st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
st->codec->codec_id = AV_CODEC_ID_ILBC;
st->codec->sample_rate = 8000;
st->codec->channels = 1;
st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
st->start_time = 0;
avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
if (!memcmp(header, mode20_header, sizeof(mode20_header) - 1)) {
st->codec->block_align = 38;
st->codec->bit_rate = 15200;
} else if (!memcmp(header, mode30_header, sizeof(mode30_header) - 1)) {
st->codec->block_align = 50;
st->codec->bit_rate = 13333;
} else {
av_log(s, AV_LOG_ERROR, "Unrecognized iLBC file header\n");
return AVERROR_INVALIDDATA;
}
return 0;
}
static int ilbc_read_packet(AVFormatContext *s,
AVPacket *pkt)
{
AVCodecContext *enc = s->streams[0]->codec;
int ret;
if ((ret = av_new_packet(pkt, enc->block_align)) < 0)
return ret;
pkt->stream_index = 0;
pkt->pos = avio_tell(s->pb);
pkt->duration = enc->block_align == 38 ? 160 : 240;
if ((ret = avio_read(s->pb, pkt->data, enc->block_align)) != enc->block_align) {
av_free_packet(pkt);
return ret < 0 ? ret : AVERROR(EIO);
}
return 0;
}
AVInputFormat ff_ilbc_demuxer = {
.name = "ilbc",
.long_name = NULL_IF_CONFIG_SMALL("iLBC storage"),
.read_probe = ilbc_probe,
.read_header = ilbc_read_header,
.read_packet = ilbc_read_packet,
.flags = AVFMT_GENERIC_INDEX,
};
AVOutputFormat ff_ilbc_muxer = {
.name = "ilbc",
.long_name = NULL_IF_CONFIG_SMALL("iLBC storage"),
.mime_type = "audio/iLBC",
.extensions = "lbc",
.audio_codec = AV_CODEC_ID_ILBC,
.write_header = ilbc_write_header,
.write_packet = ilbc_write_packet,
.flags = AVFMT_NOTIMESTAMPS,
};
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