ffmpeg/libavformat/afc.c

80 lines
2.4 KiB
C

/*
* AFC demuxer
* Copyright (c) 2012 Paul B Mahol
*
* 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 "libavutil/channel_layout.h"
#include "avformat.h"
#include "internal.h"
typedef struct AFCDemuxContext {
int64_t data_end;
} AFCDemuxContext;
static int afc_read_header(AVFormatContext *s)
{
AFCDemuxContext *c = s->priv_data;
AVStream *st;
st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
st->codecpar->codec_id = AV_CODEC_ID_ADPCM_AFC;
st->codecpar->channels = 2;
st->codecpar->channel_layout = AV_CH_LAYOUT_STEREO;
if (ff_alloc_extradata(st->codecpar, 1))
return AVERROR(ENOMEM);
st->codecpar->extradata[0] = 8 * st->codecpar->channels;
c->data_end = avio_rb32(s->pb) + 32LL;
st->duration = avio_rb32(s->pb);
st->codecpar->sample_rate = avio_rb16(s->pb);
avio_skip(s->pb, 22);
avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
return 0;
}
static int afc_read_packet(AVFormatContext *s, AVPacket *pkt)
{
AFCDemuxContext *c = s->priv_data;
int64_t size;
int ret;
size = FFMIN(c->data_end - avio_tell(s->pb), 18 * 128);
if (size <= 0)
return AVERROR_EOF;
ret = av_get_packet(s->pb, pkt, size);
pkt->stream_index = 0;
return ret;
}
AVInputFormat ff_afc_demuxer = {
.name = "afc",
.long_name = NULL_IF_CONFIG_SMALL("AFC"),
.priv_data_size = sizeof(AFCDemuxContext),
.read_header = afc_read_header,
.read_packet = afc_read_packet,
.extensions = "afc",
.flags = AVFMT_NOBINSEARCH | AVFMT_NOGENSEARCH | AVFMT_NO_BYTE_SEEK,
};