sol.c
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1 /*
2  * Sierra SOL demuxer
3  * Copyright Konstantin Shishkov
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; 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/intreadwrite.h"
27 #include "avformat.h"
28 #include "internal.h"
29 #include "pcm.h"
30 
31 /* if we don't know the size in advance */
32 #define AU_UNKNOWN_SIZE ((uint32_t)(~0))
33 
34 static int sol_probe(AVProbeData *p)
35 {
36  /* check file header */
37  uint16_t magic = AV_RL32(p->buf);
38  if ((magic == 0x0B8D || magic == 0x0C0D || magic == 0x0C8D) &&
39  p->buf[2] == 'S' && p->buf[3] == 'O' &&
40  p->buf[4] == 'L' && p->buf[5] == 0)
41  return AVPROBE_SCORE_MAX;
42  else
43  return 0;
44 }
45 
46 #define SOL_DPCM 1
47 #define SOL_16BIT 4
48 #define SOL_STEREO 16
49 
50 static enum CodecID sol_codec_id(int magic, int type)
51 {
52  if (magic == 0x0B8D)
53  {
54  if (type & SOL_DPCM) return CODEC_ID_SOL_DPCM;
55  else return CODEC_ID_PCM_U8;
56  }
57  if (type & SOL_DPCM)
58  {
59  if (type & SOL_16BIT) return CODEC_ID_SOL_DPCM;
60  else if (magic == 0x0C8D) return CODEC_ID_SOL_DPCM;
61  else return CODEC_ID_SOL_DPCM;
62  }
63  if (type & SOL_16BIT) return CODEC_ID_PCM_S16LE;
64  return CODEC_ID_PCM_U8;
65 }
66 
67 static int sol_codec_type(int magic, int type)
68 {
69  if (magic == 0x0B8D) return 1;//SOL_DPCM_OLD;
70  if (type & SOL_DPCM)
71  {
72  if (type & SOL_16BIT) return 3;//SOL_DPCM_NEW16;
73  else if (magic == 0x0C8D) return 1;//SOL_DPCM_OLD;
74  else return 2;//SOL_DPCM_NEW8;
75  }
76  return -1;
77 }
78 
79 static int sol_channels(int magic, int type)
80 {
81  if (magic == 0x0B8D || !(type & SOL_STEREO)) return 1;
82  return 2;
83 }
84 
87 {
88  unsigned int magic,tag;
89  AVIOContext *pb = s->pb;
90  unsigned int id, channels, rate, type;
91  enum CodecID codec;
92  AVStream *st;
93 
94  /* check ".snd" header */
95  magic = avio_rl16(pb);
96  tag = avio_rl32(pb);
97  if (tag != MKTAG('S', 'O', 'L', 0))
98  return -1;
99  rate = avio_rl16(pb);
100  type = avio_r8(pb);
101  avio_skip(pb, 4); /* size */
102  if (magic != 0x0B8D)
103  avio_r8(pb); /* newer SOLs contain padding byte */
104 
105  codec = sol_codec_id(magic, type);
106  channels = sol_channels(magic, type);
107 
108  if (codec == CODEC_ID_SOL_DPCM)
109  id = sol_codec_type(magic, type);
110  else id = 0;
111 
112  /* now we are ready: build format streams */
113  st = avformat_new_stream(s, NULL);
114  if (!st)
115  return -1;
117  st->codec->codec_tag = id;
118  st->codec->codec_id = codec;
119  st->codec->channels = channels;
120  st->codec->sample_rate = rate;
121  avpriv_set_pts_info(st, 64, 1, rate);
122  return 0;
123 }
124 
125 #define MAX_SIZE 4096
126 
128  AVPacket *pkt)
129 {
130  int ret;
131 
132  if (s->pb->eof_reached)
133  return AVERROR(EIO);
134  ret= av_get_packet(s->pb, pkt, MAX_SIZE);
135  if (ret < 0)
136  return ret;
137  pkt->stream_index = 0;
138 
139  /* note: we need to modify the packet size here to handle the last
140  packet */
141  pkt->size = ret;
142  return 0;
143 }
144 
146  .name = "sol",
147  .long_name = NULL_IF_CONFIG_SMALL("Sierra SOL format"),
148  .read_probe = sol_probe,
149  .read_header = sol_read_header,
150  .read_packet = sol_read_packet,
151  .read_seek = pcm_read_seek,
152 };