1 /*
2 * NSP demuxer
3 * Copyright (c) 2017 Paul B Mahol
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 "libavutil/avstring.h"
23 #include "libavutil/intreadwrite.h"
24 #include "avformat.h"
25 #include "internal.h"
26 #include "pcm.h"
27
nsp_probe(const AVProbeData * p)28 static int nsp_probe(const AVProbeData *p)
29 {
30 if (AV_RB32(p->buf) == AV_RB32("FORM") &&
31 AV_RB32(p->buf + 4) == AV_RB32("DS16"))
32 return AVPROBE_SCORE_MAX;
33 return 0;
34 }
35
nsp_read_header(AVFormatContext * s)36 static int nsp_read_header(AVFormatContext *s)
37 {
38 int channels = 0, rate = 0;
39 uint32_t chunk, size;
40 AVStream *st;
41 int64_t pos;
42
43 avio_skip(s->pb, 12);
44 st = avformat_new_stream(s, NULL);
45 if (!st)
46 return AVERROR(ENOMEM);
47
48 while (!avio_feof(s->pb)) {
49 char value[1024];
50
51 chunk = avio_rb32(s->pb);
52 size = avio_rl32(s->pb);
53 pos = avio_tell(s->pb);
54
55 switch (chunk) {
56 case MKBETAG('H', 'E', 'D', 'R'):
57 case MKBETAG('H', 'D', 'R', '8'):
58 if (size < 32)
59 return AVERROR_INVALIDDATA;
60 avio_skip(s->pb, 20);
61 rate = avio_rl32(s->pb);
62 avio_skip(s->pb, size - (avio_tell(s->pb) - pos));
63 break;
64 case MKBETAG('N', 'O', 'T', 'E'):
65 avio_get_str(s->pb, size, value, sizeof(value));
66 av_dict_set(&s->metadata, "Comment", value, 0);
67 avio_skip(s->pb, size & 1);
68 break;
69 case MKBETAG('S', 'D', 'A', 'B'):
70 channels = 2;
71 break;
72 case MKBETAG('S', 'D', '_', '2'):
73 case MKBETAG('S', 'D', '_', '3'):
74 case MKBETAG('S', 'D', '_', '4'):
75 case MKBETAG('S', 'D', '_', '5'):
76 case MKBETAG('S', 'D', '_', '6'):
77 case MKBETAG('S', 'D', '_', '7'):
78 case MKBETAG('S', 'D', '_', '8'):
79 av_log(s, AV_LOG_WARNING, "Unsupported chunk!\n");
80 case MKBETAG('S', 'D', 'A', '_'):
81 case MKBETAG('S', 'D', '_', 'A'):
82 channels = 1;
83 break;
84 }
85
86 if (channels)
87 break;
88 }
89
90 st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
91 st->codecpar->channels = channels;
92 st->codecpar->sample_rate = rate;
93 st->codecpar->codec_id = AV_CODEC_ID_PCM_S16LE;
94 st->codecpar->block_align = 2 * channels;
95
96 return 0;
97 }
98
99 AVInputFormat ff_nsp_demuxer = {
100 .name = "nsp",
101 .long_name = NULL_IF_CONFIG_SMALL("Computerized Speech Lab NSP"),
102 .read_probe = nsp_probe,
103 .read_header = nsp_read_header,
104 .read_packet = ff_pcm_read_packet,
105 .read_seek = ff_pcm_read_seek,
106 .extensions = "nsp",
107 .flags = AVFMT_GENERIC_INDEX,
108 };
109