FFmpeg
xvag.c
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1 /*
2  * XVAG 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/bswap.h"
23 #include "libavcodec/internal.h"
24 #include "avformat.h"
25 #include "internal.h"
26 
27 static int xvag_probe(const AVProbeData *p)
28 {
29  if (memcmp(p->buf, "XVAG", 4) ||
30  memcmp(p->buf+32, "fmat", 4))
31  return 0;
32 
33  return AVPROBE_SCORE_MAX;
34 }
35 
37 {
38  unsigned offset, big_endian, codec;
39  AVStream *st;
40 
41  avio_skip(s->pb, 4);
42 
43  st = avformat_new_stream(s, NULL);
44  if (!st)
45  return AVERROR(ENOMEM);
46 
48 
49  offset = avio_rl32(s->pb);
50  big_endian = offset > av_bswap32(offset);
51  if (big_endian) {
52  offset = av_bswap32(offset);
53  avio_skip(s->pb, 28);
54  codec = avio_rb32(s->pb);
55  st->codecpar->channels = avio_rb32(s->pb);
56  avio_skip(s->pb, 4);
57  st->duration = avio_rb32(s->pb);
58  avio_skip(s->pb, 8);
59  st->codecpar->sample_rate = avio_rb32(s->pb);
60  } else {
61  avio_skip(s->pb, 28);
62  codec = avio_rl32(s->pb);
63  st->codecpar->channels = avio_rl32(s->pb);
64  avio_skip(s->pb, 4);
65  st->duration = avio_rl32(s->pb);
66  avio_skip(s->pb, 8);
67  st->codecpar->sample_rate = avio_rl32(s->pb);
68  }
69 
70  if (st->codecpar->sample_rate <= 0)
71  return AVERROR_INVALIDDATA;
72  if (st->codecpar->channels <= 0 || st->codecpar->channels > FF_SANE_NB_CHANNELS)
73  return AVERROR_INVALIDDATA;
74 
75  switch (codec) {
76  case 0x1c:
78  st->codecpar->block_align = 16 * st->codecpar->channels;
79  break;
80  default:
81  avpriv_request_sample(s, "codec %X", codec);
82  return AVERROR_PATCHWELCOME;
83  };
84 
85  avio_skip(s->pb, offset - avio_tell(s->pb));
86 
87  if (avio_rb16(s->pb) == 0xFFFB) {
89  st->codecpar->block_align = 0x1000;
91  }
92 
93  avio_skip(s->pb, -2);
94  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
95 
96  return 0;
97 }
98 
100 {
101  AVCodecParameters *par = s->streams[0]->codecpar;
102 
103  return av_get_packet(s->pb, pkt, par->block_align);
104 }
105 
107  .name = "xvag",
108  .long_name = NULL_IF_CONFIG_SMALL("Sony PS3 XVAG"),
109  .read_probe = xvag_probe,
110  .read_header = xvag_read_header,
111  .read_packet = xvag_read_packet,
112  .extensions = "xvag",
113 };
#define FF_SANE_NB_CHANNELS
Definition: internal.h:86
#define NULL
Definition: coverity.c:32
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
static int xvag_probe(const AVProbeData *p)
Definition: xvag.c:27
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:4929
#define avpriv_request_sample(...)
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3968
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:334
static AVPacket pkt
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:788
This struct describes the properties of an encoded stream.
Definition: avcodec.h:3960
Format I/O context.
Definition: avformat.h:1358
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:803
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf offset
enum AVStreamParseType need_parsing
Definition: avformat.h:1099
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4502
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1426
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
full parsing and repack with timestamp and position generation by parser for raw this assumes that ea...
Definition: avformat.h:804
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:772
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
preferred ID for decoding MPEG audio layer 1, 2 or 3
Definition: avcodec.h:566
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3964
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
int block_align
Audio only.
Definition: avcodec.h:4085
#define s(width, name)
Definition: cbs_vp9.c:257
Stream structure.
Definition: avformat.h:881
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
static int xvag_read_header(AVFormatContext *s)
Definition: xvag.c:36
#define av_bswap32
Definition: bswap.h:33
AVIOContext * pb
I/O context.
Definition: avformat.h:1400
byte swapping routines
static int xvag_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: xvag.c:99
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:930
int sample_rate
Audio only.
Definition: avcodec.h:4078
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
Main libavformat public API header.
common internal api header.
AVInputFormat ff_xvag_demuxer
Definition: xvag.c:106
int channels
Audio only.
Definition: avcodec.h:4074
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:654
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1028
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
This structure stores compressed data.
Definition: avcodec.h:1457