Commit | Line | Data |
---|---|---|
2ba45a60 DM |
1 | /* |
2 | * CRYO APC audio format demuxer | |
3 | * Copyright (c) 2007 Anssi Hannula <anssi.hannula@gmail.com> | |
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 <string.h> | |
23 | ||
24 | #include "libavutil/channel_layout.h" | |
25 | #include "avformat.h" | |
26 | #include "internal.h" | |
27 | ||
28 | static int apc_probe(AVProbeData *p) | |
29 | { | |
30 | if (!strncmp(p->buf, "CRYO_APC", 8)) | |
31 | return AVPROBE_SCORE_MAX; | |
32 | ||
33 | return 0; | |
34 | } | |
35 | ||
36 | static int apc_read_header(AVFormatContext *s) | |
37 | { | |
38 | AVIOContext *pb = s->pb; | |
39 | AVStream *st; | |
40 | ||
41 | avio_rl32(pb); /* CRYO */ | |
42 | avio_rl32(pb); /* _APC */ | |
43 | avio_rl32(pb); /* 1.20 */ | |
44 | ||
45 | st = avformat_new_stream(s, NULL); | |
46 | if (!st) | |
47 | return AVERROR(ENOMEM); | |
48 | ||
49 | st->codec->codec_type = AVMEDIA_TYPE_AUDIO; | |
50 | st->codec->codec_id = AV_CODEC_ID_ADPCM_IMA_APC; | |
51 | ||
52 | avio_rl32(pb); /* number of samples */ | |
53 | st->codec->sample_rate = avio_rl32(pb); | |
54 | ||
55 | /* initial predictor values for adpcm decoder */ | |
56 | if (ff_get_extradata(st->codec, pb, 2 * 4) < 0) | |
57 | return AVERROR(ENOMEM); | |
58 | ||
59 | if (avio_rl32(pb)) { | |
60 | st->codec->channels = 2; | |
61 | st->codec->channel_layout = AV_CH_LAYOUT_STEREO; | |
62 | } else { | |
63 | st->codec->channels = 1; | |
64 | st->codec->channel_layout = AV_CH_LAYOUT_MONO; | |
65 | } | |
66 | ||
67 | st->codec->bits_per_coded_sample = 4; | |
68 | st->codec->bit_rate = st->codec->bits_per_coded_sample * st->codec->channels | |
69 | * st->codec->sample_rate; | |
70 | st->codec->block_align = 1; | |
71 | ||
72 | return 0; | |
73 | } | |
74 | ||
75 | #define MAX_READ_SIZE 4096 | |
76 | ||
77 | static int apc_read_packet(AVFormatContext *s, AVPacket *pkt) | |
78 | { | |
79 | if (av_get_packet(s->pb, pkt, MAX_READ_SIZE) <= 0) | |
80 | return AVERROR(EIO); | |
81 | pkt->flags &= ~AV_PKT_FLAG_CORRUPT; | |
82 | pkt->stream_index = 0; | |
83 | return 0; | |
84 | } | |
85 | ||
86 | AVInputFormat ff_apc_demuxer = { | |
87 | .name = "apc", | |
88 | .long_name = NULL_IF_CONFIG_SMALL("CRYO APC"), | |
89 | .read_probe = apc_probe, | |
90 | .read_header = apc_read_header, | |
91 | .read_packet = apc_read_packet, | |
92 | }; |