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 data_start;
28  unsigned block_count;
29  unsigned current_block;
30  unsigned last_block_size;
32 
33 static int vpk_probe(const AVProbeData *p)
34 {
35  if (AV_RL32(p->buf) != MKBETAG('V','P','K',' '))
36  return 0;
37 
38  return AVPROBE_SCORE_MAX / 3 * 2;
39 }
40 
42 {
43  VPKDemuxContext *vpk = s->priv_data;
44  unsigned offset;
45  unsigned samples_per_block;
46  AVStream *st;
47 
48  vpk->current_block = 0;
49  st = avformat_new_stream(s, NULL);
50  if (!st)
51  return AVERROR(ENOMEM);
52 
53  avio_skip(s->pb, 4);
54  st->duration = avio_rl32(s->pb) * 28 / 16;
55  offset = avio_rl32(s->pb);
58  st->codecpar->block_align = avio_rl32(s->pb);
59  st->codecpar->sample_rate = avio_rl32(s->pb);
60  if (st->codecpar->sample_rate <= 0 || st->codecpar->block_align <= 0)
61  return AVERROR_INVALIDDATA;
62  st->codecpar->channels = avio_rl32(s->pb);
63  if (st->codecpar->channels <= 0)
64  return AVERROR_INVALIDDATA;
65  samples_per_block = ((st->codecpar->block_align / st->codecpar->channels) * 28LL) / 16;
66  if (samples_per_block <= 0)
67  return AVERROR_INVALIDDATA;
68  vpk->block_count = (st->duration + (samples_per_block - 1)) / samples_per_block;
69  vpk->last_block_size = (st->duration % samples_per_block) * 16 * st->codecpar->channels / 28;
70 
71  if (offset < avio_tell(s->pb))
72  return AVERROR_INVALIDDATA;
73  avio_skip(s->pb, offset - avio_tell(s->pb));
74  vpk->data_start = offset;
75  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
76 
77  return 0;
78 }
79 
81 {
82  AVCodecParameters *par = s->streams[0]->codecpar;
83  VPKDemuxContext *vpk = s->priv_data;
84  int ret, i;
85 
86  vpk->current_block++;
87  if (vpk->current_block == vpk->block_count) {
88  unsigned size = vpk->last_block_size / par->channels;
89  unsigned skip = (par->block_align - vpk->last_block_size) / par->channels;
90  uint64_t pos = avio_tell(s->pb);
91 
93  if (ret < 0)
94  return ret;
95  for (i = 0; i < par->channels; i++) {
96  ret = avio_read(s->pb, pkt->data + i * size, size);
97  avio_skip(s->pb, skip);
98  if (ret != size) {
99  return AVERROR(EIO);
100  }
101  }
102  pkt->pos = pos;
103  pkt->stream_index = 0;
104  } else if (vpk->current_block < vpk->block_count) {
105  ret = av_get_packet(s->pb, pkt, par->block_align);
106  pkt->stream_index = 0;
107  } else {
108  return AVERROR_EOF;
109  }
110 
111  return ret;
112 }
113 
114 static int vpk_read_seek(AVFormatContext *s, int stream_index,
115  int64_t timestamp, int flags)
116 {
117  AVStream *st = s->streams[stream_index];
118  AVCodecParameters *par = st->codecpar;
119  VPKDemuxContext *vpk = s->priv_data;
120  int samples_per_block;
121  int64_t ret = 0;
122 
123  samples_per_block = av_get_audio_frame_duration2(par, par->block_align);
124  if (samples_per_block > 0)
125  timestamp /= samples_per_block;
126  else
127  return -1;
128  ret = avio_seek(s->pb, vpk->data_start + timestamp * par->block_align, SEEK_SET);
129  if (ret < 0)
130  return ret;
131 
132  vpk->current_block = timestamp;
133  avpriv_update_cur_dts(s, st, timestamp * samples_per_block);
134  return 0;
135 }
136 
138  .name = "vpk",
139  .long_name = NULL_IF_CONFIG_SMALL("Sony PS2 VPK"),
140  .priv_data_size = sizeof(VPKDemuxContext),
145  .extensions = "vpk",
146 };
AVERROR
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
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:760
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:52
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
vpk_read_packet
static int vpk_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: vpk.c:80
AVPacket::data
uint8_t * data
Definition: packet.h:373
vpk_read_seek
static int vpk_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: vpk.c:114
av_get_audio_frame_duration2
int av_get_audio_frame_duration2(AVCodecParameters *par, int frame_bytes)
This function is the same as av_get_audio_frame_duration(), except it works with AVCodecParameters in...
Definition: utils.c:827
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
AVCodecParameters::channels
int channels
Audio only.
Definition: codec_par.h:166
read_seek
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:149
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:504
AVStream::duration
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:973
vpk_read_header
static int vpk_read_header(AVFormatContext *s)
Definition: vpk.c:41
pkt
AVPacket * pkt
Definition: movenc.c:59
AVInputFormat
Definition: avformat.h:638
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:257
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:99
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:643
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
if
if(ret)
Definition: filter_design.txt:179
AVFormatContext
Format I/O context.
Definition: avformat.h:1188
avpriv_update_cur_dts
void avpriv_update_cur_dts(AVFormatContext *s, AVStream *ref_st, int64_t timestamp)
Update cur_dts of all streams based on the given timestamp and AVStream.
Definition: seek.c:32
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1083
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:527
NULL
#define NULL
Definition: coverity.c:32
read_probe
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:170
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:759
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:117
size
int size
Definition: twinvq_data.h:10344
MKBETAG
#define MKBETAG(a, b, c, d)
Definition: macros.h:56
VPKDemuxContext::current_block
unsigned current_block
Definition: vpk.c:29
offset
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
Definition: writing_filters.txt:86
vpk_probe
static int vpk_probe(const AVProbeData *p)
Definition: vpk.c:33
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:271
VPKDemuxContext::block_count
unsigned block_count
Definition: vpk.c:28
AVCodecParameters::block_align
int block_align
Audio only.
Definition: codec_par.h:177
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:197
ret
ret
Definition: filter_design.txt:187
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
AVStream
Stream structure.
Definition: avformat.h:923
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:260
pos
unsigned int pos
Definition: spdifenc.c:412
avformat.h
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:92
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:641
avpriv_set_pts_info
void avpriv_set_pts_info(AVStream *st, 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:1186
VPKDemuxContext
Definition: vpk.c:26
AVPacket::stream_index
int stream_index
Definition: packet.h:375
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:347
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
AVPacket
This structure stores compressed data.
Definition: packet.h:350
VPKDemuxContext::data_start
unsigned data_start
Definition: vpk.c:27
AVPacket::pos
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:393
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
ff_vpk_demuxer
const AVInputFormat ff_vpk_demuxer
Definition: vpk.c:137
AV_CODEC_ID_ADPCM_PSX
@ AV_CODEC_ID_ADPCM_PSX
Definition: codec_id.h:390
VPKDemuxContext::last_block_size
unsigned last_block_size
Definition: vpk.c:30