FFmpeg  4.0
3dostr.c
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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 
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 
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 
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'):
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 
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 
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 };
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:768
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
int size
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1450
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: utils.c:4811
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3884
static int threedostr_probe(AVProbeData *p)
Definition: 3dostr.c:25
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:331
static AVPacket pkt
Format I/O context.
Definition: avformat.h:1342
void void avpriv_request_sample(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:801
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: avcodec.h:1448
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4441
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1410
#define AVERROR_EOF
End of file.
Definition: error.h:55
int av_get_packet(AVIOContext *s, AVPacket *pkt, int size)
Allocate and read the payload of a packet and initialize its fields with default values.
Definition: utils.c:310
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
#define av_log(a,...)
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:770
#define AVERROR(e)
Definition: error.h:43
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:197
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3880
AVInputFormat ff_threedostr_demuxer
Definition: 3dostr.c:160
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:450
int block_align
Audio only.
Definition: avcodec.h:4001
Stream structure.
Definition: avformat.h:873
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
AVIOContext * pb
I/O context.
Definition: avformat.h:1384
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:470
This structure contains the data a format has to probe a file.
Definition: avformat.h:448
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:922
int sample_rate
Audio only.
Definition: avcodec.h:3994
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:460
Main libavformat public API header.
int channels
Audio only.
Definition: avcodec.h:3990
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:647
static int threedostr_read_header(AVFormatContext *s)
Definition: 3dostr.c:35
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1020
int avio_feof(AVIOContext *s)
feof() equivalent for AVIOContext.
Definition: aviobuf.c:358
int stream_index
Definition: avcodec.h:1432
#define MKTAG(a, b, c, d)
Definition: common.h:366
static int threedostr_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: 3dostr.c:111
This structure stores compressed data.
Definition: avcodec.h:1407