path: root/libavformat/3dostr.c (plain)
blob: 3668e5f6137d89b4a37d0c184be3e37bbaa8d888

1	/*
2	* 3DO STR demuxer
3	* Copyright (c) 2015 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 "avformat.h"
23	#include "internal.h"
24
25	static int threedostr_probe(AVProbeData *p)
26	{
27	if (memcmp(p->buf, "CTRL", 4) &&
28	memcmp(p->buf, "SHDR", 4) &&
29	memcmp(p->buf, "SNDS", 4))
30	return 0;
31
32	return AVPROBE_SCORE_MAX / 3 * 2;
33	}
34
35	static int threedostr_read_header(AVFormatContext *s)
36	{
37	unsigned chunk, codec = 0, size, ctrl_size = -1, found_shdr = 0;
38	AVStream *st;
39
40	while (!avio_feof(s->pb) && !found_shdr) {
41	chunk = avio_rl32(s->pb);
42	size = avio_rb32(s->pb);
43
44	if (size < 8)
45	return AVERROR_INVALIDDATA;
46	size -= 8;
47
48	switch (chunk) {
49	case MKTAG('C','T','R','L'):
50	ctrl_size = size;
51	break;
52	case MKTAG('S','N','D','S'):
53	if (size < 56)
54	return AVERROR_INVALIDDATA;
55	avio_skip(s->pb, 8);
56	if (avio_rl32(s->pb) != MKTAG('S','H','D','R'))
57	return AVERROR_INVALIDDATA;
58	avio_skip(s->pb, 24);
59
60	st = avformat_new_stream(s, NULL);
61	if (!st)
62	return AVERROR(ENOMEM);
63
64	st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
65	st->codecpar->sample_rate = avio_rb32(s->pb);
66	st->codecpar->channels = avio_rb32(s->pb);
67	if (st->codecpar->channels <= 0)
68	return AVERROR_INVALIDDATA;
69	codec = avio_rl32(s->pb);
70	avio_skip(s->pb, 4);
71	if (ctrl_size == 20 || ctrl_size == 3 || ctrl_size == -1)
72	st->duration = (avio_rb32(s->pb) - 1) / st->codecpar->channels;
73	else
74	st->duration = avio_rb32(s->pb) * 16 / st->codecpar->channels;
75	size -= 56;
76	found_shdr = 1;
77	break;
78	case MKTAG('S','H','D','R'):
79	if (size > 0x78) {
80	avio_skip(s->pb, 0x74);
81	size -= 0x78;
82	if (avio_rl32(s->pb) == MKTAG('C','T','R','L') && size > 4) {
83	ctrl_size = avio_rb32(s->pb);
84	size -= 4;
85	}
86	}
87	break;
88	default:
89	av_log(s, AV_LOG_DEBUG, "skipping unknown chunk: %X\n", chunk);
90	break;
91	}
92
93	avio_skip(s->pb, size);
94	}
95
96	switch (codec) {
97	case MKTAG('S','D','X','2'):
98	st->codecpar->codec_id = AV_CODEC_ID_SDX2_DPCM;
99	st->codecpar->block_align = 1 * st->codecpar->channels;
100	break;
101	default:
102	avpriv_request_sample(s, "codec %X", codec);
103	return AVERROR_PATCHWELCOME;
104	}
105
106	avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
107
108	return 0;
109	}
110
111	static int threedostr_read_packet(AVFormatContext *s, AVPacket *pkt)
112	{
113	unsigned chunk, size, found_ssmp = 0;
114	AVStream *st = s->streams[0];
115	int64_t pos;
116	int ret = 0;
117
118	while (!found_ssmp) {
119	if (avio_feof(s->pb))
120	return AVERROR_EOF;
121
122	pos = avio_tell(s->pb);
123	chunk = avio_rl32(s->pb);
124	size = avio_rb32(s->pb);
125
126	if (!size)
127	continue;
128
129	if (size < 8)
130	return AVERROR_INVALIDDATA;
131	size -= 8;
132
133	switch (chunk) {
134	case MKTAG('S','N','D','S'):
135	if (size <= 16)
136	return AVERROR_INVALIDDATA;
137	avio_skip(s->pb, 8);
138	if (avio_rl32(s->pb) != MKTAG('S','S','M','P'))
139	return AVERROR_INVALIDDATA;
140	avio_skip(s->pb, 4);
141	size -= 16;
142	ret = av_get_packet(s->pb, pkt, size);
143	pkt->pos = pos;
144	pkt->stream_index = 0;
145	pkt->duration = size / st->codecpar->channels;
146	size = 0;
147	found_ssmp = 1;
148	break;
149	default:
150	av_log(s, AV_LOG_DEBUG, "skipping unknown chunk: %X\n", chunk);
151	break;
152	}
153
154	avio_skip(s->pb, size);
155	}
156
157	return ret;
158	}
159
160	AVInputFormat ff_threedostr_demuxer = {
161	.name = "3dostr",
162	.long_name = NULL_IF_CONFIG_SMALL("3DO STR"),
163	.read_probe = threedostr_probe,
164	.read_header = threedostr_read_header,
165	.read_packet = threedostr_read_packet,
166	.extensions = "str",
167	.flags = AVFMT_GENERIC_INDEX,
168	};
169