FFmpeg: libavformat/vpk.c Source File

FFmpeg
vpk.c
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1 /*
2  * VPK 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  typedef struct VPKDemuxContext {
27   unsigned block_count;
28   unsigned current_block;
29   unsigned last_block_size;
30 } VPKDemuxContext;
31 
32  static int vpk_probe(AVProbeData *p)
33 {
34  if (AV_RL32(p->buf) != MKBETAG('V','P','K',' '))
35  return 0;
36 
37  return AVPROBE_SCORE_MAX / 3 * 2;
38 }
39 
40  static int vpk_read_header(AVFormatContext *s)
41 {
42  VPKDemuxContext *vpk = s->priv_data;
43  unsigned offset;
44  unsigned samples_per_block;
45  AVStream *st;
46 
47  vpk->current_block = 0;
48  st = avformat_new_stream(s, NULL);
49  if (!st)
50  return AVERROR(ENOMEM);
51 
52  avio_skip(s->pb, 4);
53  st->duration = avio_rl32(s->pb) * 28 / 16;
54  offset = avio_rl32(s->pb);
55  st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
56  st->codecpar->codec_id = AV_CODEC_ID_ADPCM_PSX;
57  st->codecpar->block_align = avio_rl32(s->pb);
58  st->codecpar->sample_rate = avio_rl32(s->pb);
59  if (st->codecpar->sample_rate <= 0)
60  return AVERROR_INVALIDDATA;
61  st->codecpar->channels = avio_rl32(s->pb);
62  if (st->codecpar->channels <= 0)
63  return AVERROR_INVALIDDATA;
64  samples_per_block = ((st->codecpar->block_align / st->codecpar->channels) * 28) / 16;
65  if (samples_per_block <= 0)
66  return AVERROR_INVALIDDATA;
67  vpk->block_count = (st->duration + (samples_per_block - 1)) / samples_per_block;
68  vpk->last_block_size = (st->duration % samples_per_block) * 16 * st->codecpar->channels / 28;
69  avio_skip(s->pb, offset - avio_tell(s->pb));
70  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
71 
72  return 0;
73 }
74 
75  static int vpk_read_packet(AVFormatContext *s, AVPacket *pkt)
76 {
77  AVCodecParameters *par = s->streams[0]->codecpar;
78  VPKDemuxContext *vpk = s->priv_data;
79  int ret, i;
80 
81  vpk->current_block++;
82  if (vpk->current_block == vpk->block_count) {
83  unsigned size = vpk->last_block_size / par->channels;
84  unsigned skip = (par->block_align - vpk->last_block_size) / par->channels;
85 
86  ret = av_new_packet(pkt, vpk->last_block_size);
87  if (ret < 0)
88  return ret;
89  for (i = 0; i < par->channels; i++) {
90  ret = avio_read(s->pb, pkt->data + i * size, size);
91  avio_skip(s->pb, skip);
92  if (ret != size) {
93  av_packet_unref(pkt);
94  ret = AVERROR(EIO);
95  break;
96  }
97  }
98  pkt->stream_index = 0;
99  } else if (vpk->current_block < vpk->block_count) {
100  ret = av_get_packet(s->pb, pkt, par->block_align);
101  pkt->stream_index = 0;
102  } else {
103  return AVERROR_EOF;
104  }
105 
106  return ret;
107 }
108 
109  AVInputFormat ff_vpk_demuxer = {
110  .name = "vpk",
111  .long_name = NULL_IF_CONFIG_SMALL("Sony PS2 VPK"),
112  .priv_data_size = sizeof(VPKDemuxContext),
113  .read_probe = vpk_probe,
114  .read_header = vpk_read_header,
115  .read_packet = vpk_read_packet,
116  .extensions = "vpk",
117 };
NULL
#define NULL
Definition: coverity.c:32
s
const char * s
Definition: avisynth_c.h:768
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
VPKDemuxContext::block_count
unsigned block_count
Definition: vpk.c:27
avpriv_set_pts_info
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:4820
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3884
vpk_read_header
static int vpk_read_header(AVFormatContext *s)
Definition: vpk.c:40
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:331
pkt
static AVPacket pkt
Definition: demuxing_decoding.c:54
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: avcodec.h:3876
AVFormatContext
Format I/O context.
Definition: avformat.h:1342
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4450
AVFormatContext::streams
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1410
AVPacket::data
uint8_t * data
Definition: avcodec.h:1430
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:55
av_get_packet
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
size
ptrdiff_t size
Definition: opengl_enc.c:101
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:648
av_new_packet
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:86
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:770
AVERROR
#define AVERROR(e)
Definition: error.h:43
vpk_probe
static int vpk_probe(AVProbeData *p)
Definition: vpk.c:32
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3880
AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
offset
static const uint8_t offset[127][2]
Definition: vf_spp.c:92
vpk_read_packet
static int vpk_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: vpk.c:75
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:450
AVCodecParameters::block_align
int block_align
Audio only.
Definition: avcodec.h:4001
read_probe
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:55
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:530
AVStream
Stream structure.
Definition: avformat.h:873
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
AVFormatContext::pb
AVIOContext * pb
I/O context.
Definition: avformat.h:1384
ff_vpk_demuxer
AVInputFormat ff_vpk_demuxer
Definition: vpk.c:109
av_packet_unref
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:592
VPKDemuxContext::last_block_size
unsigned last_block_size
Definition: vpk.c:29
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:448
AV_CODEC_ID_ADPCM_PSX
Definition: avcodec.h:528
AVStream::duration
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:922
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: avcodec.h:3994
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:460
avformat.h
Main libavformat public API header.
MKBETAG
#define MKBETAG(a, b, c, d)
Definition: common.h:367
VPKDemuxContext::current_block
unsigned current_block
Definition: vpk.c:28
AVFormatContext::priv_data
void * priv_data
Format private data.
Definition: avformat.h:1370
AVCodecParameters::channels
int channels
Audio only.
Definition: avcodec.h:3990
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:647
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1020
AVPacket::stream_index
int stream_index
Definition: avcodec.h:1432
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
AVPacket
This structure stores compressed data.
Definition: avcodec.h:1407
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