path: root/libavformat/wsddec.c (plain)
blob: 81a4dcc71e956402f008073f7995cd80c27a48db

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
28	static int wsd_probe(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
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
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
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
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_string(playback_time, avio_rb32(pb), 0);
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 & (1 << i))
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	AVInputFormat ff_wsd_demuxer = {
165	.name = "wsd",
166	.long_name = NULL_IF_CONFIG_SMALL("Wideband Single-bit Data (WSD)"),
167	.read_probe = wsd_probe,
168	.read_header = wsd_read_header,
169	.read_packet = ff_raw_read_partial_packet,
170	.extensions = "wsd",
171	.flags = AVFMT_GENERIC_INDEX | AVFMT_NO_BYTE_SEEK,
172	.raw_codec_id = AV_CODEC_ID_DSD_MSBF,
173	};
174