FFmpeg
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 "libavutil/intreadwrite.h"
23 #include "avformat.h"
24 #include "internal.h"
25 
26 static int threedostr_probe(const AVProbeData *p)
27 {
28  for (int i = 0; i < p->buf_size;) {
29  unsigned chunk = AV_RL32(p->buf + i);
30  unsigned size = AV_RB32(p->buf + i + 4);
31 
32  if (size < 8 || p->buf_size - i < size)
33  return 0;
34  i += 8;
35  size -= 8;
36  switch (chunk) {
37  case MKTAG('C','T','R','L'):
38  break;
39  case MKTAG('S','N','D','S'):
40  if (size < 56)
41  return 0;
42  i += 8;
43  if (AV_RL32(p->buf + i) != MKTAG('S','H','D','R'))
44  return 0;
45  i += 28;
46 
47  if (AV_RB32(p->buf + i) <= 0)
48  return 0;
49  i += 4;
50  if (AV_RB32(p->buf + i) <= 0)
51  return 0;
52  i += 4;
53  if (AV_RL32(p->buf + i) == MKTAG('S','D','X','2'))
54  return AVPROBE_SCORE_MAX;
55  else
56  return 0;
57  break;
58  case MKTAG('S','H','D','R'):
59  if (size > 0x78) {
60  i += 0x78;
61  size -= 0x78;
62  }
63  break;
64  default:
65  break;
66  }
67 
68  i += size;
69  }
70 
71  return 0;
72 }
73 
75 {
76  unsigned chunk, codec = 0, size, ctrl_size = -1, found_shdr = 0;
77  AVStream *st;
78 
79  while (!avio_feof(s->pb) && !found_shdr) {
80  chunk = avio_rl32(s->pb);
81  size = avio_rb32(s->pb);
82 
83  if (size < 8)
84  return AVERROR_INVALIDDATA;
85  size -= 8;
86 
87  switch (chunk) {
88  case MKTAG('C','T','R','L'):
89  ctrl_size = size;
90  break;
91  case MKTAG('S','N','D','S'):
92  if (size < 56)
93  return AVERROR_INVALIDDATA;
94  avio_skip(s->pb, 8);
95  if (avio_rl32(s->pb) != MKTAG('S','H','D','R'))
96  return AVERROR_INVALIDDATA;
97  avio_skip(s->pb, 24);
98 
99  st = avformat_new_stream(s, NULL);
100  if (!st)
101  return AVERROR(ENOMEM);
102 
104  st->codecpar->sample_rate = avio_rb32(s->pb);
105  st->codecpar->channels = avio_rb32(s->pb);
106  if (st->codecpar->channels <= 0)
107  return AVERROR_INVALIDDATA;
108  codec = avio_rl32(s->pb);
109  avio_skip(s->pb, 4);
110  if (ctrl_size == 20 || ctrl_size == 3 || ctrl_size == -1)
111  st->duration = (avio_rb32(s->pb) - 1) / st->codecpar->channels;
112  else
113  st->duration = avio_rb32(s->pb) * 16 / st->codecpar->channels;
114  size -= 56;
115  found_shdr = 1;
116  break;
117  case MKTAG('S','H','D','R'):
118  if (size > 0x78) {
119  avio_skip(s->pb, 0x74);
120  size -= 0x78;
121  if (avio_rl32(s->pb) == MKTAG('C','T','R','L') && size > 4) {
122  ctrl_size = avio_rb32(s->pb);
123  size -= 4;
124  }
125  }
126  break;
127  default:
128  av_log(s, AV_LOG_DEBUG, "skipping unknown chunk: %X\n", chunk);
129  break;
130  }
131 
132  avio_skip(s->pb, size);
133  }
134 
135  switch (codec) {
136  case MKTAG('S','D','X','2'):
138  st->codecpar->block_align = 1 * st->codecpar->channels;
139  break;
140  default:
141  avpriv_request_sample(s, "codec %X", codec);
142  return AVERROR_PATCHWELCOME;
143  }
144 
145  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
146 
147  return 0;
148 }
149 
151 {
152  unsigned chunk, size;
153  AVStream *st = s->streams[0];
154  int64_t pos;
155  int ret = 0;
156 
157  while (!avio_feof(s->pb)) {
158  pos = avio_tell(s->pb);
159  chunk = avio_rl32(s->pb);
160  size = avio_rb32(s->pb);
161 
162  if (!size)
163  continue;
164 
165  if (size < 8)
166  return AVERROR_INVALIDDATA;
167  size -= 8;
168 
169  switch (chunk) {
170  case MKTAG('S','N','D','S'):
171  if (size <= 16)
172  return AVERROR_INVALIDDATA;
173  avio_skip(s->pb, 8);
174  if (avio_rl32(s->pb) != MKTAG('S','S','M','P'))
175  return AVERROR_INVALIDDATA;
176  avio_skip(s->pb, 4);
177  size -= 16;
178  ret = av_get_packet(s->pb, pkt, size);
179  pkt->pos = pos;
180  pkt->stream_index = 0;
181  pkt->duration = size / st->codecpar->channels;
182  return ret;
183  default:
184  av_log(s, AV_LOG_DEBUG, "skipping unknown chunk: %X\n", chunk);
185  break;
186  }
187 
188  avio_skip(s->pb, size);
189  }
190 
191  return AVERROR_EOF;
192 }
193 
195  .name = "3dostr",
196  .long_name = NULL_IF_CONFIG_SMALL("3DO STR"),
197  .read_probe = threedostr_probe,
198  .read_header = threedostr_read_header,
199  .read_packet = threedostr_read_packet,
200  .extensions = "str",
201  .flags = AVFMT_GENERIC_INDEX,
202 };
#define NULL
Definition: coverity.c:32
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:383
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:4869
#define avpriv_request_sample(...)
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:341
static AVPacket pkt
Format I/O context.
Definition: avformat.h:1351
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:790
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:381
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4450
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_RB32
Definition: bytestream.h:87
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1419
#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:305
ptrdiff_t size
Definition: opengl_enc.c:100
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:759
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:153
unsigned int pos
Definition: spdifenc.c:410
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:215
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
AVInputFormat ff_threedostr_demuxer
Definition: 3dostr.c:194
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:444
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:443
int block_align
Audio only.
Definition: codec_par.h:177
#define s(width, name)
Definition: cbs_vp9.c:257
Stream structure.
Definition: avformat.h:876
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
AVIOContext * pb
I/O context.
Definition: avformat.h:1393
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:463
This structure contains the data a format has to probe a file.
Definition: avformat.h:441
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:925
int sample_rate
Audio only.
Definition: codec_par.h:170
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:453
static int threedostr_probe(const AVProbeData *p)
Definition: 3dostr.c:26
Main libavformat public API header.
int channels
Audio only.
Definition: codec_par.h:166
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:650
static int threedostr_read_header(AVFormatContext *s)
Definition: 3dostr.c:74
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1023
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:368
int stream_index
Definition: packet.h:365
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
#define MKTAG(a, b, c, d)
Definition: common.h:406
static int threedostr_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: 3dostr.c:150
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
This structure stores compressed data.
Definition: packet.h:340
int i
Definition: input.c:407