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svag.c
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1 /*
2  * SVAG 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 svag_probe(AVProbeData *p)
26 {
27  if (memcmp(p->buf, "Svag", 4))
28  return 0;
29 
30  return AVPROBE_SCORE_MAX;
31 }
32 
34 {
35  unsigned size, align;
36  AVStream *st;
37 
38  avio_skip(s->pb, 4);
39 
40  st = avformat_new_stream(s, NULL);
41  if (!st)
42  return AVERROR(ENOMEM);
43 
44  size = avio_rl32(s->pb);
47  st->codecpar->sample_rate = avio_rl32(s->pb);
48  if (st->codecpar->sample_rate <= 0)
49  return AVERROR_INVALIDDATA;
50  st->codecpar->channels = avio_rl32(s->pb);
51  if (st->codecpar->channels <= 0 || st->codecpar->channels > 8)
52  return AVERROR_INVALIDDATA;
53  st->duration = size / (16 * st->codecpar->channels) * 28;
54  align = avio_rl32(s->pb);
55  if (align <= 0 || align > INT_MAX / st->codecpar->channels)
56  return AVERROR_INVALIDDATA;
57  st->codecpar->block_align = align * st->codecpar->channels;
58  avio_skip(s->pb, 0x800 - avio_tell(s->pb));
59  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
60 
61  return 0;
62 }
63 
65 {
66  AVCodecParameters *par = s->streams[0]->codecpar;
67 
68  return av_get_packet(s->pb, pkt, par->block_align);
69 }
70 
72  .name = "svag",
73  .long_name = NULL_IF_CONFIG_SMALL("Konami PS2 SVAG"),
74  .read_probe = svag_probe,
75  .read_header = svag_read_header,
76  .read_packet = svag_read_packet,
77  .extensions = "svag",
78 };
#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
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:4601
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:4066
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:316
static AVPacket pkt
This struct describes the properties of an encoded stream.
Definition: avcodec.h:4058
Format I/O context.
Definition: avformat.h:1349
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4231
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1417
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:289
ptrdiff_t size
Definition: opengl_enc.c:101
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:525
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:738
#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:179
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:4062
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:463
int block_align
Audio only.
Definition: avcodec.h:4183
Stream structure.
Definition: avformat.h:889
const AVS_VideoInfo int align
Definition: avisynth_c.h:795
static int svag_probe(AVProbeData *p)
Definition: svag.c:25
AVIOContext * pb
I/O context.
Definition: avformat.h:1391
static int svag_read_header(AVFormatContext *s)
Definition: svag.c:33
static int svag_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: svag.c:64
AVInputFormat ff_svag_demuxer
Definition: svag.c:71
This structure contains the data a format has to probe a file.
Definition: avformat.h:461
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:946
int sample_rate
Audio only.
Definition: avcodec.h:4176
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:473
Main libavformat public API header.
int channels
Audio only.
Definition: avcodec.h:4172
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:664
AVCodecParameters * codecpar
Definition: avformat.h:1252
This structure stores compressed data.
Definition: avcodec.h:1634