libavformat/sol.c

   1 /*
   2  * Sierra SOL demuxer
   3  * Copyright Konstantin Shishkov
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 /*
  23  * Based on documents from Game Audio Player and own research
  24  */
  25
  26 #include "libavutil/channel_layout.h"
  27 #include "libavutil/intreadwrite.h"
  28 #include "avformat.h"
  29 #include "demux.h"
  30 #include "internal.h"
  31 #include "pcm.h"
  32
  33 /* if we don't know the size in advance */
  34 #define AU_UNKNOWN_SIZE ((uint32_t)(~0))
  35
  36 static int sol_probe(const AVProbeData *p)
  37 {
  38     /* check file header */
  39     uint16_t magic = AV_RL32(p->buf);
  40     if ((magic == 0x0B8D || magic == 0x0C0D || magic == 0x0C8D) &&
  41         p->buf[2] == 'S' && p->buf[3] == 'O' &&
  42         p->buf[4] == 'L' && p->buf[5] == 0)
  43         return AVPROBE_SCORE_MAX;
  44     else
  45         return 0;
  46 }
  47
  48 #define SOL_DPCM    1
  49 #define SOL_16BIT   4
  50 #define SOL_STEREO 16
  51
  52 static enum AVCodecID sol_codec_id(int magic, int type)
  53 {
  54     if (type & SOL_DPCM)
  55         return AV_CODEC_ID_SOL_DPCM;
  56
  57     if (magic == 0x0B8D)
  58         return AV_CODEC_ID_PCM_U8;
  59
  60     if (type & SOL_16BIT)
  61         return AV_CODEC_ID_PCM_S16LE;
  62
  63     return AV_CODEC_ID_PCM_U8;
  64 }
  65
  66 static int sol_codec_type(int magic, int type)
  67 {
  68     if (magic == 0x0B8D) return 1;//SOL_DPCM_OLD;
  69     if (type & SOL_DPCM)
  70     {
  71         if (type & SOL_16BIT) return 3;//SOL_DPCM_NEW16;
  72         else if (magic == 0x0C8D) return 1;//SOL_DPCM_OLD;
  73         else return 2;//SOL_DPCM_NEW8;
  74     }
  75     return -1;
  76 }
  77
  78 static int sol_channels(int magic, int type)
  79 {
  80     if (magic == 0x0B8D || !(type & SOL_STEREO)) return 1;
  81     return 2;
  82 }
  83
  84 static int sol_read_header(AVFormatContext *s)
  85 {
  86     unsigned int magic,tag;
  87     AVIOContext *pb = s->pb;
  88     unsigned int id, channels, rate, type;
  89     enum AVCodecID codec;
  90     AVStream *st;
  91
  92     /* check ".snd" header */
  93     magic = avio_rl16(pb);
  94     tag = avio_rl32(pb);
  95     if (tag != MKTAG('S', 'O', 'L', 0))
  96         return -1;
  97     rate = avio_rl16(pb);
  98     type = avio_r8(pb);
  99     avio_skip(pb, 4); /* size */
 100     if (magic != 0x0B8D)
 101         avio_r8(pb); /* newer SOLs contain padding byte */
 102
 103     codec = sol_codec_id(magic, type);
 104     channels = sol_channels(magic, type);
 105
 106     if (codec == AV_CODEC_ID_SOL_DPCM)
 107         id = sol_codec_type(magic, type);
 108     else id = 0;
 109
 110     /* now we are ready: build format streams */
 111     st = avformat_new_stream(s, NULL);
 112     if (!st)
 113         return -1;
 114     st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
 115     st->codecpar->codec_tag = id;
 116     st->codecpar->codec_id = codec;
 117     av_channel_layout_default(&st->codecpar->ch_layout,channels);
 118     st->codecpar->sample_rate = rate;
 119     avpriv_set_pts_info(st, 64, 1, rate);
 120     return 0;
 121 }
 122
 123 #define MAX_SIZE 4096
 124
 125 static int sol_read_packet(AVFormatContext *s,
 126                           AVPacket *pkt)
 127 {
 128     int ret;
 129
 130     if (avio_feof(s->pb))
 131         return AVERROR_EOF;
 132
 133     ret= av_get_packet(s->pb, pkt, MAX_SIZE);
 134     if (ret < 0)
 135         return ret;
 136     pkt->flags &= ~AV_PKT_FLAG_CORRUPT;
 137     pkt->stream_index = 0;
 138     return 0;
 139 }
 140
 141 const FFInputFormat ff_sol_demuxer = {
 142     .p.name         = "sol",
 143     .p.long_name    = NULL_IF_CONFIG_SMALL("Sierra SOL"),
 144     .read_probe     = sol_probe,
 145     .read_header    = sol_read_header,
 146     .read_packet    = sol_read_packet,
 147     .read_seek      = ff_pcm_read_seek,
 148 };