mirror of
https://github.com/FFmpeg/FFmpeg.git
synced 2024-12-18 03:19:31 +02:00
c6610a216e
This also lists the objects from those two libraries as internal (by adding the ff_ prefix) so that they can then be hidden via linker scripts.
91 lines
2.5 KiB
C
91 lines
2.5 KiB
C
/*
|
|
* CRYO APC audio format demuxer
|
|
* Copyright (c) 2007 Anssi Hannula <anssi.hannula@gmail.com>
|
|
*
|
|
* 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 <string.h>
|
|
#include "avformat.h"
|
|
|
|
static int apc_probe(AVProbeData *p)
|
|
{
|
|
if (!strncmp(p->buf, "CRYO_APC", 8))
|
|
return AVPROBE_SCORE_MAX;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int apc_read_header(AVFormatContext *s, AVFormatParameters *ap)
|
|
{
|
|
ByteIOContext *pb = s->pb;
|
|
AVStream *st;
|
|
|
|
get_le32(pb); /* CRYO */
|
|
get_le32(pb); /* _APC */
|
|
get_le32(pb); /* 1.20 */
|
|
|
|
st = av_new_stream(s, 0);
|
|
if (!st)
|
|
return AVERROR(ENOMEM);
|
|
|
|
st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
|
|
st->codec->codec_id = CODEC_ID_ADPCM_IMA_WS;
|
|
|
|
get_le32(pb); /* number of samples */
|
|
st->codec->sample_rate = get_le32(pb);
|
|
|
|
st->codec->extradata_size = 2 * 4;
|
|
st->codec->extradata = av_malloc(st->codec->extradata_size +
|
|
FF_INPUT_BUFFER_PADDING_SIZE);
|
|
if (!st->codec->extradata)
|
|
return AVERROR(ENOMEM);
|
|
|
|
/* initial predictor values for adpcm decoder */
|
|
get_buffer(pb, st->codec->extradata, 2 * 4);
|
|
|
|
st->codec->channels = 1;
|
|
if (get_le32(pb))
|
|
st->codec->channels = 2;
|
|
|
|
st->codec->bits_per_coded_sample = 4;
|
|
st->codec->bit_rate = st->codec->bits_per_coded_sample * st->codec->channels
|
|
* st->codec->sample_rate;
|
|
st->codec->block_align = 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
#define MAX_READ_SIZE 4096
|
|
|
|
static int apc_read_packet(AVFormatContext *s, AVPacket *pkt)
|
|
{
|
|
if (av_get_packet(s->pb, pkt, MAX_READ_SIZE) <= 0)
|
|
return AVERROR(EIO);
|
|
pkt->stream_index = 0;
|
|
return 0;
|
|
}
|
|
|
|
AVInputFormat ff_apc_demuxer = {
|
|
"apc",
|
|
NULL_IF_CONFIG_SMALL("CRYO APC format"),
|
|
0,
|
|
apc_probe,
|
|
apc_read_header,
|
|
apc_read_packet,
|
|
};
|