ffmpeg/libavformat/adp.c

99 lines
2.6 KiB
C

/*
* ADP demuxer
* Copyright (c) 2013 James Almer
*
* 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 "libavutil/intreadwrite.h"
#include "avformat.h"
#include "internal.h"
static int adp_probe(AVProbeData *p)
{
int i, changes = 0;
char last = 0;
if (p->buf_size < 32)
return 0;
for (i = 0; i < p->buf_size - 3; i+=32) {
if (p->buf[i] != p->buf[i+2] || p->buf[i+1] != p->buf[i+3])
return 0;
if (p->buf[i] != last)
changes++;
last = p->buf[i];
}
if (changes <= 1)
return 0;
return p->buf_size < 260 ? 1 : AVPROBE_SCORE_MAX / 4;
}
static int adp_read_header(AVFormatContext *s)
{
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_DTK;
st->codecpar->channel_layout = AV_CH_LAYOUT_STEREO;
st->codecpar->channels = 2;
st->codecpar->sample_rate = 48000;
st->start_time = 0;
if (s->pb->seekable)
st->duration = av_get_audio_frame_duration2(st->codecpar, avio_size(s->pb));
avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
return 0;
}
static int adp_read_packet(AVFormatContext *s, AVPacket *pkt)
{
int ret, size = 1024;
if (avio_feof(s->pb))
return AVERROR_EOF;
ret = av_get_packet(s->pb, pkt, size);
if (ret != size) {
if (ret < 0) {
av_packet_unref(pkt);
return ret;
}
av_shrink_packet(pkt, ret);
}
pkt->stream_index = 0;
return ret;
}
AVInputFormat ff_adp_demuxer = {
.name = "adp",
.long_name = NULL_IF_CONFIG_SMALL("ADP"),
.read_probe = adp_probe,
.read_header = adp_read_header,
.read_packet = adp_read_packet,
.extensions = "adp,dtk",
};