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sol.c
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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 
27 #include "libavutil/intreadwrite.h"
28 #include "avformat.h"
29 #include "internal.h"
30 #include "pcm.h"
31 
32 /* if we don't know the size in advance */
33 #define AU_UNKNOWN_SIZE ((uint32_t)(~0))
34 
35 static int sol_probe(AVProbeData *p)
36 {
37  /* check file header */
38  uint16_t magic = AV_RL32(p->buf);
39  if ((magic == 0x0B8D || magic == 0x0C0D || magic == 0x0C8D) &&
40  p->buf[2] == 'S' && p->buf[3] == 'O' &&
41  p->buf[4] == 'L' && p->buf[5] == 0)
42  return AVPROBE_SCORE_MAX;
43  else
44  return 0;
45 }
46 
47 #define SOL_DPCM 1
48 #define SOL_16BIT 4
49 #define SOL_STEREO 16
50 
51 static enum AVCodecID sol_codec_id(int magic, int type)
52 {
53  if (type & SOL_DPCM)
54  return AV_CODEC_ID_SOL_DPCM;
55 
56  if (magic == 0x0B8D)
57  return AV_CODEC_ID_PCM_U8;
58 
59  if (type & SOL_16BIT)
60  return AV_CODEC_ID_PCM_S16LE;
61 
62  return AV_CODEC_ID_PCM_U8;
63 }
64 
65 static int sol_codec_type(int magic, int type)
66 {
67  if (magic == 0x0B8D) return 1;//SOL_DPCM_OLD;
68  if (type & SOL_DPCM)
69  {
70  if (type & SOL_16BIT) return 3;//SOL_DPCM_NEW16;
71  else if (magic == 0x0C8D) return 1;//SOL_DPCM_OLD;
72  else return 2;//SOL_DPCM_NEW8;
73  }
74  return -1;
75 }
76 
77 static int sol_channels(int magic, int type)
78 {
79  if (magic == 0x0B8D || !(type & SOL_STEREO)) return 1;
80  return 2;
81 }
82 
84 {
85  unsigned int magic,tag;
86  AVIOContext *pb = s->pb;
87  unsigned int id, channels, rate, type;
88  enum AVCodecID codec;
89  AVStream *st;
90 
91  /* check ".snd" header */
92  magic = avio_rl16(pb);
93  tag = avio_rl32(pb);
94  if (tag != MKTAG('S', 'O', 'L', 0))
95  return -1;
96  rate = avio_rl16(pb);
97  type = avio_r8(pb);
98  avio_skip(pb, 4); /* size */
99  if (magic != 0x0B8D)
100  avio_r8(pb); /* newer SOLs contain padding byte */
101 
102  codec = sol_codec_id(magic, type);
103  channels = sol_channels(magic, type);
104 
105  if (codec == AV_CODEC_ID_SOL_DPCM)
106  id = sol_codec_type(magic, type);
107  else id = 0;
108 
109  /* now we are ready: build format streams */
110  st = avformat_new_stream(s, NULL);
111  if (!st)
112  return -1;
114  st->codec->codec_tag = id;
115  st->codec->codec_id = codec;
116  st->codec->channels = channels;
117  st->codec->channel_layout = channels == 1 ? AV_CH_LAYOUT_MONO :
119  st->codec->sample_rate = rate;
120  avpriv_set_pts_info(st, 64, 1, rate);
121  return 0;
122 }
123 
124 #define MAX_SIZE 4096
125 
127  AVPacket *pkt)
128 {
129  int ret;
130 
131  if (avio_feof(s->pb))
132  return AVERROR(EIO);
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 
142  .name = "sol",
143  .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 };