cosmetics: indentation
[libav.git] / libavformat / vocdec.c
1 /*
2 * Creative Voice File demuxer.
3 * Copyright (c) 2006 Aurelien Jacobs <aurel@gnuage.org>
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 #include "voc.h"
23
24
25 static int voc_probe(AVProbeData *p)
26 {
27 int version, check;
28
29 if (memcmp(p->buf, voc_magic, sizeof(voc_magic) - 1))
30 return 0;
31 version = AV_RL16(p->buf + 22);
32 check = AV_RL16(p->buf + 24);
33 if (~version + 0x1234 != check)
34 return 10;
35
36 return AVPROBE_SCORE_MAX;
37 }
38
39 static int voc_read_header(AVFormatContext *s, AVFormatParameters *ap)
40 {
41 voc_dec_context_t *voc = s->priv_data;
42 ByteIOContext *pb = &s->pb;
43 int header_size;
44 AVStream *st;
45
46 url_fskip(pb, 20);
47 header_size = get_le16(pb) - 22;
48 if (header_size != 4) {
49 av_log(s, AV_LOG_ERROR, "unknown header size: %d\n", header_size);
50 return AVERROR_NOTSUPP;
51 }
52 url_fskip(pb, header_size);
53 st = av_new_stream(s, 0);
54 if (!st)
55 return AVERROR_NOMEM;
56 st->codec->codec_type = CODEC_TYPE_AUDIO;
57
58 voc->remaining_size = 0;
59 return 0;
60 }
61
62 int
63 voc_get_packet(AVFormatContext *s, AVPacket *pkt, AVStream *st, int max_size)
64 {
65 voc_dec_context_t *voc = s->priv_data;
66 AVCodecContext *dec = st->codec;
67 ByteIOContext *pb = &s->pb;
68 voc_type_t type;
69 int size;
70 int sample_rate = 0;
71 int channels = 1;
72
73 while (!voc->remaining_size) {
74 type = get_byte(pb);
75 if (type == VOC_TYPE_EOF)
76 return AVERROR_IO;
77 voc->remaining_size = get_le24(pb);
78 max_size -= 4;
79
80 switch (type) {
81 case VOC_TYPE_VOICE_DATA:
82 dec->sample_rate = 1000000 / (256 - get_byte(pb));
83 if (sample_rate)
84 dec->sample_rate = sample_rate;
85 dec->channels = channels;
86 dec->codec_id = codec_get_id(voc_codec_tags, get_byte(pb));
87 dec->bits_per_sample = av_get_bits_per_sample(dec->codec_id);
88 voc->remaining_size -= 2;
89 max_size -= 2;
90 channels = 1;
91 break;
92
93 case VOC_TYPE_VOICE_DATA_CONT:
94 break;
95
96 case VOC_TYPE_EXTENDED:
97 sample_rate = get_le16(pb);
98 get_byte(pb);
99 channels = get_byte(pb) + 1;
100 sample_rate = 256000000 / (channels * (65536 - sample_rate));
101 voc->remaining_size = 0;
102 max_size -= 4;
103 break;
104
105 case VOC_TYPE_NEW_VOICE_DATA:
106 dec->sample_rate = get_le32(pb);
107 dec->bits_per_sample = get_byte(pb);
108 dec->channels = get_byte(pb);
109 dec->codec_id = codec_get_id(voc_codec_tags, get_le16(pb));
110 url_fskip(pb, 4);
111 voc->remaining_size -= 12;
112 max_size -= 12;
113 break;
114
115 default:
116 url_fskip(pb, voc->remaining_size);
117 max_size -= voc->remaining_size;
118 voc->remaining_size = 0;
119 break;
120 }
121 }
122
123 dec->bit_rate = dec->sample_rate * dec->bits_per_sample;
124
125 if (max_size <= 0)
126 max_size = 2048;
127 size = FFMIN(voc->remaining_size, max_size);
128 voc->remaining_size -= size;
129 return av_get_packet(pb, pkt, size);
130 }
131
132 static int voc_read_packet(AVFormatContext *s, AVPacket *pkt)
133 {
134 return voc_get_packet(s, pkt, s->streams[0], 0);
135 }
136
137 AVInputFormat voc_demuxer = {
138 "voc",
139 "Creative Voice File format",
140 sizeof(voc_dec_context_t),
141 voc_probe,
142 voc_read_header,
143 voc_read_packet,
144 .codec_tag=(const AVCodecTag*[]){voc_codec_tags, 0},
145 };