FFmpeg  4.0
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(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
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:4811
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3884
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:331
static AVPacket pkt
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:786
This struct describes the properties of an encoded stream.
Definition: avcodec.h:3876
static int xvag_probe(AVProbeData *p)
Definition: xvag.c:27
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
enum AVStreamParseType need_parsing
Definition: avformat.h:1091
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
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:797
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
preferred ID for decoding MPEG audio layer 1, 2 or 3
Definition: avcodec.h:552
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3880
static const uint8_t offset[127][2]
Definition: vf_spp.c:92
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
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:1384
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: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.
common internal api header.
AVInputFormat ff_xvag_demuxer
Definition: xvag.c:106
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
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1020
This structure stores compressed data.
Definition: avcodec.h:1407