93 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			93 lines
		
	
	
		
			2.6 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 "libavutil/channel_layout.h"
 | 
						|
#include "avformat.h"
 | 
						|
#include "internal.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)
 | 
						|
{
 | 
						|
    AVIOContext *pb = s->pb;
 | 
						|
    AVStream *st;
 | 
						|
 | 
						|
    avio_rl32(pb); /* CRYO */
 | 
						|
    avio_rl32(pb); /* _APC */
 | 
						|
    avio_rl32(pb); /* 1.20 */
 | 
						|
 | 
						|
    st = avformat_new_stream(s, NULL);
 | 
						|
    if (!st)
 | 
						|
        return AVERROR(ENOMEM);
 | 
						|
 | 
						|
    st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
 | 
						|
    st->codec->codec_id = AV_CODEC_ID_ADPCM_IMA_APC;
 | 
						|
 | 
						|
    avio_rl32(pb); /* number of samples */
 | 
						|
    st->codec->sample_rate = avio_rl32(pb);
 | 
						|
 | 
						|
    /* initial predictor values for adpcm decoder */
 | 
						|
    if (ff_get_extradata(st->codec, pb, 2 * 4) < 0)
 | 
						|
        return AVERROR(ENOMEM);
 | 
						|
 | 
						|
    if (avio_rl32(pb)) {
 | 
						|
        st->codec->channels       = 2;
 | 
						|
        st->codec->channel_layout = AV_CH_LAYOUT_STEREO;
 | 
						|
    } else {
 | 
						|
        st->codec->channels       = 1;
 | 
						|
        st->codec->channel_layout = AV_CH_LAYOUT_MONO;
 | 
						|
    }
 | 
						|
 | 
						|
    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->flags &= ~AV_PKT_FLAG_CORRUPT;
 | 
						|
    pkt->stream_index = 0;
 | 
						|
    return 0;
 | 
						|
}
 | 
						|
 | 
						|
AVInputFormat ff_apc_demuxer = {
 | 
						|
    .name           = "apc",
 | 
						|
    .long_name      = NULL_IF_CONFIG_SMALL("CRYO APC"),
 | 
						|
    .read_probe     = apc_probe,
 | 
						|
    .read_header    = apc_read_header,
 | 
						|
    .read_packet    = apc_read_packet,
 | 
						|
};
 |