FFmpeg
kvag.c
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1 /*
2  * Simon & Schuster Interactive VAG (de)muxer
3  *
4  * Copyright (C) 2020 Zane van Iperen (zane@zanevaniperen.com)
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 #include "avformat.h"
23 #include "internal.h"
24 #include "rawenc.h"
25 #include "libavutil/intreadwrite.h"
26 
27 #define KVAG_TAG MKTAG('K', 'V', 'A', 'G')
28 #define KVAG_HEADER_SIZE 14
29 #define KVAG_MAX_READ_SIZE 4096
30 
31 typedef struct KVAGHeader {
32  uint32_t magic;
33  uint32_t data_size;
34  uint32_t sample_rate;
35  uint16_t stereo;
36 } KVAGHeader;
37 
38 #if CONFIG_KVAG_DEMUXER
39 static int kvag_probe(const AVProbeData *p)
40 {
41  if (AV_RL32(p->buf) != KVAG_TAG)
42  return 0;
43 
44  return AVPROBE_SCORE_EXTENSION + 1;
45 }
46 
47 static int kvag_read_header(AVFormatContext *s)
48 {
49  int ret;
50  AVStream *st;
51  KVAGHeader hdr;
52  AVCodecParameters *par;
53  uint8_t buf[KVAG_HEADER_SIZE];
54 
55  if (!(st = avformat_new_stream(s, NULL)))
56  return AVERROR(ENOMEM);
57 
58  if ((ret = avio_read(s->pb, buf, KVAG_HEADER_SIZE)) < 0)
59  return ret;
60  else if (ret != KVAG_HEADER_SIZE)
61  return AVERROR(EIO);
62 
63  hdr.magic = AV_RL32(buf + 0);
64  hdr.data_size = AV_RL32(buf + 4);
65  hdr.sample_rate = AV_RL32(buf + 8);
66  hdr.stereo = AV_RL16(buf + 12);
67 
68  par = st->codecpar;
72 
73  if (hdr.stereo) {
75  par->channels = 2;
76  } else {
78  par->channels = 1;
79  }
80 
81  par->sample_rate = hdr.sample_rate;
82  par->bits_per_coded_sample = 4;
83  par->bits_per_raw_sample = 16;
84  par->block_align = 1;
85  par->bit_rate = par->channels *
86  (uint64_t)par->sample_rate *
88 
89  avpriv_set_pts_info(st, 64, 1, par->sample_rate);
90  st->start_time = 0;
91  st->duration = hdr.data_size *
92  (8 / par->bits_per_coded_sample) /
93  par->channels;
94 
95  return 0;
96 }
97 
98 static int kvag_read_packet(AVFormatContext *s, AVPacket *pkt)
99 {
100  int ret;
101  AVCodecParameters *par = s->streams[0]->codecpar;
102 
103  if ((ret = av_get_packet(s->pb, pkt, KVAG_MAX_READ_SIZE)) < 0)
104  return ret;
105 
107  pkt->stream_index = 0;
108  pkt->duration = ret * (8 / par->bits_per_coded_sample) / par->channels;
109 
110  return 0;
111 }
112 
113 static int kvag_seek(AVFormatContext *s, int stream_index,
114  int64_t pts, int flags)
115 {
116  if (pts != 0)
117  return AVERROR(EINVAL);
118 
119  return avio_seek(s->pb, KVAG_HEADER_SIZE, SEEK_SET);
120 }
121 
123  .name = "kvag",
124  .long_name = NULL_IF_CONFIG_SMALL("Simon & Schuster Interactive VAG"),
125  .read_probe = kvag_probe,
126  .read_header = kvag_read_header,
127  .read_packet = kvag_read_packet,
128  .read_seek = kvag_seek,
129 };
130 #endif
131 
132 #if CONFIG_KVAG_MUXER
133 static int kvag_write_init(AVFormatContext *s)
134 {
135  AVCodecParameters *par;
136 
137  if (s->nb_streams != 1) {
138  av_log(s, AV_LOG_ERROR, "KVAG files have exactly one stream\n");
139  return AVERROR(EINVAL);
140  }
141 
142  par = s->streams[0]->codecpar;
143 
144  if (par->codec_id != AV_CODEC_ID_ADPCM_IMA_SSI) {
145  av_log(s, AV_LOG_ERROR, "%s codec not supported\n",
146  avcodec_get_name(par->codec_id));
147  return AVERROR(EINVAL);
148  }
149 
150  if (par->channels > 2) {
151  av_log(s, AV_LOG_ERROR, "KVAG files only support up to 2 channels\n");
152  return AVERROR(EINVAL);
153  }
154 
155  if (!(s->pb->seekable & AVIO_SEEKABLE_NORMAL)) {
156  av_log(s, AV_LOG_WARNING, "Stream not seekable, unable to write output file\n");
157  return AVERROR(EINVAL);
158  }
159 
160  return 0;
161 }
162 
163 static int kvag_write_header(AVFormatContext *s)
164 {
165  uint8_t buf[KVAG_HEADER_SIZE];
166  AVCodecParameters *par = s->streams[0]->codecpar;
167 
168  AV_WL32(buf + 0, KVAG_TAG);
169  AV_WL32(buf + 4, 0); /* Data size, we fix this up later. */
170  AV_WL32(buf + 8, par->sample_rate);
171  AV_WL16(buf + 12, par->channels == 2);
172 
173  avio_write(s->pb, buf, sizeof(buf));
174  return 0;
175 }
176 
177 static int kvag_write_trailer(AVFormatContext *s)
178 {
179  int64_t file_size, data_size;
180 
181  file_size = avio_tell(s->pb);
182  data_size = file_size - KVAG_HEADER_SIZE;
183  if (data_size < UINT32_MAX) {
184  avio_seek(s->pb, 4, SEEK_SET);
185  avio_wl32(s->pb, (uint32_t)data_size);
186  avio_seek(s->pb, file_size, SEEK_SET);
187  } else {
189  "Filesize %"PRId64" invalid for KVAG, output file will be broken\n",
190  file_size);
191  }
192 
193  return 0;
194 }
195 
197  .name = "kvag",
198  .long_name = NULL_IF_CONFIG_SMALL("Simon & Schuster Interactive VAG"),
199  .extensions = "vag",
200  .audio_codec = AV_CODEC_ID_ADPCM_IMA_SSI,
201  .video_codec = AV_CODEC_ID_NONE,
202  .init = kvag_write_init,
203  .write_header = kvag_write_header,
204  .write_packet = ff_raw_write_packet,
205  .write_trailer = kvag_write_trailer
206 };
207 #endif
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:187
AVOutputFormat::name
const char * name
Definition: avformat.h:496
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:4376
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
AV_WL32
#define AV_WL32(p, v)
Definition: intreadwrite.h:426
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:52
AV_CH_LAYOUT_MONO
#define AV_CH_LAYOUT_MONO
Definition: channel_layout.h:90
AVPacket::duration
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:383
KVAG_TAG
#define KVAG_TAG
Definition: kvag.c:27
AVCodecParameters::channels
int channels
Audio only.
Definition: codec_par.h:166
AVCodecParameters::bits_per_raw_sample
int bits_per_raw_sample
This is the number of valid bits in each output sample.
Definition: codec_par.h:115
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:538
pts
static int64_t pts
Definition: transcode_aac.c:652
AVStream::duration
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:880
AV_CH_LAYOUT_STEREO
#define AV_CH_LAYOUT_STEREO
Definition: channel_layout.h:91
pkt
AVPacket * pkt
Definition: movenc.c:59
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:181
AVInputFormat
Definition: avformat.h:621
AV_PKT_FLAG_CORRUPT
#define AV_PKT_FLAG_CORRUPT
The packet content is corrupted.
Definition: packet.h:397
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:257
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:626
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
KVAGHeader
Definition: kvag.c:31
ff_raw_write_packet
int ff_raw_write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: rawenc.c:29
AV_RL16
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:94
ff_kvag_muxer
const AVOutputFormat ff_kvag_muxer
AVFormatContext
Format I/O context.
Definition: avformat.h:1097
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:984
ff_kvag_demuxer
const AVInputFormat ff_kvag_demuxer
NULL
#define NULL
Definition: coverity.c:32
KVAG_MAX_READ_SIZE
#define KVAG_MAX_READ_SIZE
Definition: kvag.c:29
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
KVAGHeader::magic
uint32_t magic
Definition: kvag.c:32
AVPROBE_SCORE_EXTENSION
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:456
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:170
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
KVAGHeader::sample_rate
uint32_t sample_rate
Definition: kvag.c:34
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:4801
avio_write
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:215
AV_WL16
#define AV_WL16(p, v)
Definition: intreadwrite.h:412
avio_wl32
void avio_wl32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:365
AVPacket::flags
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:371
KVAGHeader::stereo
uint16_t stereo
Definition: kvag.c:35
rawenc.h
avcodec_get_name
const char * avcodec_get_name(enum AVCodecID id)
Get the name of a codec.
Definition: utils.c:448
AV_CODEC_ID_NONE
@ AV_CODEC_ID_NONE
Definition: codec_id.h:48
AVOutputFormat
Definition: avformat.h:495
AVCodecParameters::block_align
int block_align
Audio only.
Definition: codec_par.h:177
AV_SAMPLE_FMT_S16
@ AV_SAMPLE_FMT_S16
signed 16 bits
Definition: samplefmt.h:61
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:280
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:837
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:243
avformat.h
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:92
AVIO_SEEKABLE_NORMAL
#define AVIO_SEEKABLE_NORMAL
Seeking works like for a local file.
Definition: avio.h:40
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:616
AVPacket::stream_index
int stream_index
Definition: packet.h:367
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:102
AVCodecParameters::format
int format
Definition: codec_par.h:84
AV_CODEC_ID_ADPCM_IMA_SSI
@ AV_CODEC_ID_ADPCM_IMA_SSI
Definition: codec_id.h:395
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:342
KVAGHeader::data_size
uint32_t data_size
Definition: kvag.c:33
AVCodecParameters::channel_layout
uint64_t channel_layout
Audio only.
Definition: codec_par.h:162
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
AVCodecParameters::bit_rate
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:89
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
AVStream::start_time
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base.
Definition: avformat.h:870
KVAG_HEADER_SIZE
#define KVAG_HEADER_SIZE
Definition: kvag.c:28