1 /*
2  * Wideband Single-bit Data (WSD) demuxer
3  * Copyright (c) 2014 Peter Ross
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/intreadwrite.h"
23 #include "libavutil/timecode.h"
24 #include "avformat.h"
25 #include "internal.h"
26 #include "rawdec.h"
27 
wsd_probe(const AVProbeData * p)28 static int wsd_probe(const AVProbeData *p)
29 {
30     if (p->buf_size < 45 || memcmp(p->buf, "1bit", 4) ||
31         !AV_RB32(p->buf + 36) || !p->buf[44] ||
32         (p->buf[0] >= 0x10 && (AV_RB32(p->buf + 20) < 0x80 || AV_RB32(p->buf + 24) < 0x80)))
33        return 0;
34     return AVPROBE_SCORE_MAX;
35 }
36 
empty_string(const char * buf,unsigned size)37 static int empty_string(const char *buf, unsigned size)
38 {
39     while (size--) {
40        if (*buf++ != ' ')
41            return 0;
42     }
43     return 1;
44 }
45 
wsd_to_av_channel_layoyt(AVFormatContext * s,int bit)46 static int wsd_to_av_channel_layoyt(AVFormatContext *s, int bit)
47 {
48     switch (bit) {
49     case 2: return AV_CH_BACK_RIGHT;
50     case 3:
51         avpriv_request_sample(s, "Rr-middle");
52         break;
53     case 4: return AV_CH_BACK_CENTER;
54     case 5:
55         avpriv_request_sample(s, "Lr-middle");
56         break;
57     case 6: return AV_CH_BACK_LEFT;
58     case 24: return AV_CH_LOW_FREQUENCY;
59     case 26: return AV_CH_FRONT_RIGHT;
60     case 27: return AV_CH_FRONT_RIGHT_OF_CENTER;
61     case 28: return AV_CH_FRONT_CENTER;
62     case 29: return AV_CH_FRONT_LEFT_OF_CENTER;
63     case 30: return AV_CH_FRONT_LEFT;
64     default:
65         av_log(s, AV_LOG_WARNING, "reserved channel assignment\n");
66         break;
67     }
68     return 0;
69 }
70 
get_metadata(AVFormatContext * s,const char * const tag,const unsigned size)71 static int get_metadata(AVFormatContext *s, const char *const tag, const unsigned size)
72 {
73     uint8_t *buf;
74     if (!(size + 1))
75         return AVERROR(ENOMEM);
76 
77     buf = av_malloc(size + 1);
78     if (!buf)
79         return AVERROR(ENOMEM);
80 
81     if (avio_read(s->pb, buf, size) != size) {
82         av_free(buf);
83         return AVERROR(EIO);
84     }
85 
86     if (empty_string(buf, size)) {
87         av_free(buf);
88         return 0;
89     }
90 
91     buf[size] = 0;
92     av_dict_set(&s->metadata, tag, buf, AV_DICT_DONT_STRDUP_VAL);
93     return 0;
94 }
95 
wsd_read_header(AVFormatContext * s)96 static int wsd_read_header(AVFormatContext *s)
97 {
98     AVIOContext *pb = s->pb;
99     AVStream *st;
100     int version;
101     uint32_t text_offset, data_offset, channel_assign;
102     char playback_time[AV_TIMECODE_STR_SIZE];
103 
104     st = avformat_new_stream(s, NULL);
105     if (!st)
106         return AVERROR(ENOMEM);
107 
108     avio_skip(pb, 8);
109     version = avio_r8(pb);
110     av_log(s, AV_LOG_DEBUG, "version: %i.%i\n", version >> 4, version & 0xF);
111     avio_skip(pb, 11);
112 
113     if (version < 0x10) {
114         text_offset = 0x80;
115         data_offset = 0x800;
116         avio_skip(pb, 8);
117     } else {
118         text_offset = avio_rb32(pb);
119         data_offset = avio_rb32(pb);
120     }
121 
122     avio_skip(pb, 4);
123     av_timecode_make_smpte_tc_string2(playback_time, (AVRational){1,1}, avio_rb32(pb) & 0x00ffffffU, 1, 1);
124     av_dict_set(&s->metadata, "playback_time", playback_time, 0);
125 
126     st->codecpar->codec_type  = AVMEDIA_TYPE_AUDIO;
127     st->codecpar->codec_id    = s->iformat->raw_codec_id;
128     st->codecpar->sample_rate = avio_rb32(pb) / 8;
129     avio_skip(pb, 4);
130     st->codecpar->channels    = avio_r8(pb) & 0xF;
131     st->codecpar->bit_rate    = (int64_t)st->codecpar->channels * st->codecpar->sample_rate * 8LL;
132     if (!st->codecpar->channels)
133         return AVERROR_INVALIDDATA;
134 
135     avio_skip(pb, 3);
136     channel_assign         = avio_rb32(pb);
137     if (!(channel_assign & 1)) {
138         int i;
139         for (i = 1; i < 32; i++)
140             if ((channel_assign >> i) & 1)
141                 st->codecpar->channel_layout |= wsd_to_av_channel_layoyt(s, i);
142     }
143 
144     avio_skip(pb, 16);
145     if (avio_rb32(pb))
146        avpriv_request_sample(s, "emphasis");
147 
148     if (avio_seek(pb, text_offset, SEEK_SET) >= 0) {
149         get_metadata(s, "title",       128);
150         get_metadata(s, "composer",    128);
151         get_metadata(s, "song_writer", 128);
152         get_metadata(s, "artist",      128);
153         get_metadata(s, "album",       128);
154         get_metadata(s, "genre",        32);
155         get_metadata(s, "date",         32);
156         get_metadata(s, "location",     32);
157         get_metadata(s, "comment",     512);
158         get_metadata(s, "user",        512);
159     }
160 
161     return avio_seek(pb, data_offset, SEEK_SET);
162 }
163 
164 FF_RAW_DEMUXER_CLASS(wsd)
165 AVInputFormat ff_wsd_demuxer = {
166     .name         = "wsd",
167     .long_name    = NULL_IF_CONFIG_SMALL("Wideband Single-bit Data (WSD)"),
168     .read_probe   = wsd_probe,
169     .read_header  = wsd_read_header,
170     .read_packet  = ff_raw_read_partial_packet,
171     .extensions   = "wsd",
172     .flags        = AVFMT_GENERIC_INDEX | AVFMT_NO_BYTE_SEEK,
173     .raw_codec_id = AV_CODEC_ID_DSD_MSBF,
174     .priv_data_size = sizeof(FFRawDemuxerContext),
175     .priv_class     = &wsd_demuxer_class,
176 };
177