FFmpeg
musx.c
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1 /*
2  * MUSX demuxer
3  * Copyright (c) 2016 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/avassert.h"
23 #include "avformat.h"
24 #include "internal.h"
25 
26 static int musx_probe(const AVProbeData *p)
27 {
28  if (memcmp(p->buf, "MUSX", 4))
29  return 0;
30 
31  return AVPROBE_SCORE_MAX / 5 * 2;
32 }
33 
35 {
36  unsigned type, version, coding, offset;
37  AVStream *st;
38 
39  avio_skip(s->pb, 8);
40  version = avio_rl32(s->pb);
41  if (version != 10 &&
42  version != 6 &&
43  version != 5 &&
44  version != 4 &&
45  version != 201) {
46  avpriv_request_sample(s, "Unsupported version: %d", version);
47  return AVERROR_PATCHWELCOME;
48  }
49  avio_skip(s->pb, 4);
50 
51  st = avformat_new_stream(s, NULL);
52  if (!st)
53  return AVERROR(ENOMEM);
54 
55  if (version == 201) {
56  avio_skip(s->pb, 8);
57  offset = avio_rl32(s->pb);
60  st->codecpar->channels = 2;
61  st->codecpar->sample_rate = 32000;
62  st->codecpar->block_align = 0x80 * st->codecpar->channels;
63  } else if (version == 10) {
64  type = avio_rl32(s->pb);
66  offset = 0x800;
67  switch (type) {
68  case MKTAG('P', 'S', '3', '_'):
69  st->codecpar->channels = 2;
70  st->codecpar->sample_rate = 44100;
71  avio_skip(s->pb, 44);
72  coding = avio_rl32(s->pb);
73  if (coding == MKTAG('D', 'A', 'T', '4') ||
74  coding == MKTAG('D', 'A', 'T', '8')) {
75  avio_skip(s->pb, 4);
76  st->codecpar->channels = avio_rl32(s->pb);
77  if (st->codecpar->channels <= 0 ||
78  st->codecpar->channels > INT_MAX / 0x20)
79  return AVERROR_INVALIDDATA;
80  st->codecpar->sample_rate = avio_rl32(s->pb);
81  }
83  st->codecpar->block_align = 0x20 * st->codecpar->channels;
84  break;
85  case MKTAG('W', 'I', 'I', '_'):
86  avio_skip(s->pb, 44);
87  coding = avio_rl32(s->pb);
88  if (coding != MKTAG('D', 'A', 'T', '4') &&
89  coding != MKTAG('D', 'A', 'T', '8')) {
90  avpriv_request_sample(s, "Unsupported coding: %X", coding);
91  return AVERROR_PATCHWELCOME;
92  }
93  avio_skip(s->pb, 4);
95  st->codecpar->channels = avio_rl32(s->pb);
96  if (st->codecpar->channels <= 0 ||
97  st->codecpar->channels > INT_MAX / 0x20)
98  return AVERROR_INVALIDDATA;
99  st->codecpar->sample_rate = avio_rl32(s->pb);
100  st->codecpar->block_align = 0x20 * st->codecpar->channels;
101  break;
102  case MKTAG('X', 'E', '_', '_'):
104  st->codecpar->channels = 2;
105  st->codecpar->sample_rate = 32000;
106  st->codecpar->block_align = 0x20 * st->codecpar->channels;
107  break;
108  case MKTAG('P', 'S', 'P', '_'):
110  st->codecpar->channels = 2;
111  st->codecpar->sample_rate = 32768;
112  st->codecpar->block_align = 0x80 * st->codecpar->channels;
113  break;
114  case MKTAG('P', 'S', '2', '_'):
116  st->codecpar->channels = 2;
117  st->codecpar->sample_rate = 32000;
118  st->codecpar->block_align = 0x80 * st->codecpar->channels;
119  break;
120  default:
121  avpriv_request_sample(s, "Unsupported type: %X", type);
122  return AVERROR_PATCHWELCOME;
123  }
124  } else if (version == 6 || version == 5 || version == 4) {
125  type = avio_rl32(s->pb);
126  avio_skip(s->pb, 20);
128  st->codecpar->channels = 2;
129  switch (type) {
130  case MKTAG('G', 'C', '_', '_'):
132  st->codecpar->block_align = 0x20 * st->codecpar->channels;
133  st->codecpar->sample_rate = 32000;
134  offset = avio_rb32(s->pb);
135  break;
136  case MKTAG('P', 'S', '2', '_'):
138  st->codecpar->block_align = 0x80 * st->codecpar->channels;
139  st->codecpar->sample_rate = 32000;
140  offset = avio_rl32(s->pb);
141  break;
142  case MKTAG('X', 'B', '_', '_'):
144  st->codecpar->block_align = 0x20 * st->codecpar->channels;
145  st->codecpar->sample_rate = 44100;
146  offset = avio_rl32(s->pb);
147  break;
148  default:
149  avpriv_request_sample(s, "Unsupported type: %X", type);
150  return AVERROR_PATCHWELCOME;
151  }
152  } else {
153  av_assert0(0);
154  }
155 
156  avio_seek(s->pb, offset, SEEK_SET);
157 
158  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
159 
160  return 0;
161 }
162 
164 {
165  AVCodecParameters *par = s->streams[0]->codecpar;
166 
167  return av_get_packet(s->pb, pkt, par->block_align);
168 }
169 
171  .name = "musx",
172  .long_name = NULL_IF_CONFIG_SMALL("Eurocom MUSX"),
173  .read_probe = musx_probe,
174  .read_header = musx_read_header,
175  .read_packet = musx_read_packet,
176  .extensions = "musx",
177 };
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:4480
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3953
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: avcodec.h:3949
MKTAG
#define MKTAG(a, b, c, d)
Definition: common.h:366
musx_read_packet
static int musx_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: musx.c:163
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
AVCodecParameters::channels
int channels
Audio only.
Definition: avcodec.h:4063
type
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 type
Definition: writing_filters.txt:86
avassert.h
avio_rb32
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:800
AVInputFormat
Definition: avformat.h:640
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:645
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
av_assert0
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
version
int version
Definition: avisynth_c.h:858
AVFormatContext
Format I/O context.
Definition: avformat.h:1342
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1017
NULL
#define NULL
Definition: coverity.c:32
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
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: avcodec.h:4067
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:769
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:188
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:4910
musx_probe
static int musx_probe(const AVProbeData *p)
Definition: musx.c:26
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
AVCodecParameters::block_align
int block_align
Audio only.
Definition: avcodec.h:4074
musx_read_header
static int musx_read_header(AVFormatContext *s)
Definition: musx.c:34
AV_CODEC_ID_ADPCM_IMA_DAT4
@ AV_CODEC_ID_ADPCM_IMA_DAT4
Definition: avcodec.h:542
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:313
AVStream
Stream structure.
Definition: avformat.h:870
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:246
avformat.h
ff_musx_demuxer
AVInputFormat ff_musx_demuxer
Definition: musx.c:170
pkt
static AVPacket pkt
Definition: demuxing_decoding.c:54
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:331
avpriv_request_sample
#define avpriv_request_sample(...)
Definition: tableprint_vlc.h:39
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3957
AVPacket
This structure stores compressed data.
Definition: avcodec.h:1454
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
AV_CODEC_ID_ADPCM_PSX
@ AV_CODEC_ID_ADPCM_PSX
Definition: avcodec.h:540