/*
  * 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->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
     st->codecpar->codec_id = AV_CODEC_ID_ADPCM_IMA_APC;

     avio_rl32(pb); /* number of samples */

     st->codecpar->sample_rate = avio_rl32(pb);

 
     /* initial predictor values for adpcm decoder */

     if (ff_get_extradata(s, st->codecpar, pb, 2 * 4) < 0)

         return AVERROR(ENOMEM);

     if (avio_rl32(pb)) {

         st->codecpar->channels       = 2;
         st->codecpar->channel_layout = AV_CH_LAYOUT_STEREO;

     } else {

         st->codecpar->channels       = 1;
         st->codecpar->channel_layout = AV_CH_LAYOUT_MONO;

     }

     st->codecpar->bits_per_coded_sample = 4;

     st->codecpar->bit_rate = (int64_t)st->codecpar->bits_per_coded_sample * st->codecpar->channels

                           * st->codecpar->sample_rate;
     st->codecpar->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,

 };