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 "demux.h"
25 #include "internal.h"
26 
27 typedef struct VPKDemuxContext {
28  unsigned data_start;
29  unsigned block_count;
30  unsigned current_block;
31  unsigned last_block_size;
33 
34 static int vpk_probe(const AVProbeData *p)
35 {
36  if (AV_RL32(p->buf) != MKBETAG('V','P','K',' '))
37  return 0;
38 
39  return AVPROBE_SCORE_MAX / 3 * 2;
40 }
41 
43 {
44  VPKDemuxContext *vpk = s->priv_data;
45  unsigned offset;
46  unsigned samples_per_block;
47  AVStream *st;
48 
49  vpk->current_block = 0;
50  st = avformat_new_stream(s, NULL);
51  if (!st)
52  return AVERROR(ENOMEM);
53 
54  avio_skip(s->pb, 4);
55  st->duration = avio_rl32(s->pb) * 28 / 16;
56  offset = avio_rl32(s->pb);
59  st->codecpar->block_align = avio_rl32(s->pb);
60  st->codecpar->sample_rate = avio_rl32(s->pb);
61  if (st->codecpar->sample_rate <= 0 || st->codecpar->block_align <= 0)
62  return AVERROR_INVALIDDATA;
64  if (st->codecpar->ch_layout.nb_channels <= 0)
65  return AVERROR_INVALIDDATA;
66  samples_per_block = ((st->codecpar->block_align / st->codecpar->ch_layout.nb_channels) * 28LL) / 16;
67  if (samples_per_block <= 0)
68  return AVERROR_INVALIDDATA;
69  vpk->block_count = (st->duration + (samples_per_block - 1)) / samples_per_block;
70  vpk->last_block_size = (st->duration % samples_per_block) * 16 * st->codecpar->ch_layout.nb_channels / 28;
71 
72  if (offset < avio_tell(s->pb))
73  return AVERROR_INVALIDDATA;
74  avio_skip(s->pb, offset - avio_tell(s->pb));
75  vpk->data_start = offset;
76  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
77 
78  return 0;
79 }
80 
82 {
83  AVCodecParameters *par = s->streams[0]->codecpar;
84  VPKDemuxContext *vpk = s->priv_data;
85  int ret, i;
86 
87  vpk->current_block++;
88  if (vpk->current_block == vpk->block_count) {
89  unsigned size = vpk->last_block_size / par->ch_layout.nb_channels;
90  unsigned skip = (par->block_align - vpk->last_block_size) / par->ch_layout.nb_channels;
91  uint64_t pos = avio_tell(s->pb);
92 
94  if (ret < 0)
95  return ret;
96  for (i = 0; i < par->ch_layout.nb_channels; i++) {
97  ret = avio_read(s->pb, pkt->data + i * size, size);
98  avio_skip(s->pb, skip);
99  if (ret != size) {
100  return AVERROR(EIO);
101  }
102  }
103  pkt->pos = pos;
104  pkt->stream_index = 0;
105  } else if (vpk->current_block < vpk->block_count) {
106  ret = av_get_packet(s->pb, pkt, par->block_align);
107  pkt->stream_index = 0;
108  } else {
109  return AVERROR_EOF;
110  }
111 
112  return ret;
113 }
114 
115 static int vpk_read_seek(AVFormatContext *s, int stream_index,
116  int64_t timestamp, int flags)
117 {
118  AVStream *st = s->streams[stream_index];
119  AVCodecParameters *par = st->codecpar;
120  VPKDemuxContext *vpk = s->priv_data;
121  int samples_per_block;
122  int64_t ret = 0;
123 
124  samples_per_block = av_get_audio_frame_duration2(par, par->block_align);
125  if (samples_per_block > 0)
126  timestamp /= samples_per_block;
127  else
128  return -1;
129  ret = avio_seek(s->pb, vpk->data_start + timestamp * par->block_align, SEEK_SET);
130  if (ret < 0)
131  return ret;
132 
133  vpk->current_block = timestamp;
134  avpriv_update_cur_dts(s, st, timestamp * samples_per_block);
135  return 0;
136 }
137 
139  .name = "vpk",
140  .long_name = NULL_IF_CONFIG_SMALL("Sony PS2 VPK"),
141  .priv_data_size = sizeof(VPKDemuxContext),
146  .extensions = "vpk",
147 };
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
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:51
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:47
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const struct AVCodec *c)
Add a new stream to a media file.
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:81
AVPacket::data
uint8_t * data
Definition: packet.h:491
vpk_read_seek
static int vpk_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: vpk.c:115
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:317
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:35
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:464
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: avformat.c:761
read_seek
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:151
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:513
AVStream::duration
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:900
vpk_read_header
static int vpk_read_header(AVFormatContext *s)
Definition: vpk.c:42
pkt
AVPacket * pkt
Definition: movenc.c:59
AVInputFormat
Definition: avformat.h:549
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_read_callback.c:41
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:198
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:98
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:554
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:454
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:1115
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:864
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:550
NULL
#define NULL
Definition: coverity.c:32
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:452
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:206
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:171
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:777
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:106
size
int size
Definition: twinvq_data.h:10344
MKBETAG
#define MKBETAG(a, b, c, d)
Definition: macros.h:56
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:812
VPKDemuxContext::current_block
unsigned current_block
Definition: vpk.c:30
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:34
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:255
VPKDemuxContext::block_count
unsigned block_count
Definition: vpk.c:29
AVCodecParameters::block_align
int block_align
Audio only.
Definition: codec_par.h:178
demux.h
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:103
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:841
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:278
pos
unsigned int pos
Definition: spdifenc.c:413
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:659
VPKDemuxContext
Definition: vpk.c:27
AVPacket::stream_index
int stream_index
Definition: packet.h:493
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:365
read_probe
static int read_probe(const AVProbeData *p)
Definition: cdg.c:29
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:55
AVPacket
This structure stores compressed data.
Definition: packet.h:468
VPKDemuxContext::data_start
unsigned data_start
Definition: vpk.c:28
AVPacket::pos
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:511
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:474
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:138
AV_CODEC_ID_ADPCM_PSX
@ AV_CODEC_ID_ADPCM_PSX
Definition: codec_id.h:406
skip
static void BS_FUNC() skip(BSCTX *bc, unsigned int n)
Skip n bits in the buffer.
Definition: bitstream_template.h:375
VPKDemuxContext::last_block_size
unsigned last_block_size
Definition: vpk.c:31