FFmpeg
sdxdec.c
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1 /*
2  * SDX demuxer
3  * Copyright (c) 2017 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/avstring.h"
23 #include "libavutil/intreadwrite.h"
24 #include "avformat.h"
25 #include "internal.h"
26 #include "pcm.h"
27 
28 static int sdx_probe(const AVProbeData *p)
29 {
30  if (AV_RB32(p->buf) == AV_RB32("SDX:"))
32  return 0;
33 }
34 
36 {
37  AVStream *st;
38  int depth, length;
39 
40  avio_skip(s->pb, 4);
41  while (!avio_feof(s->pb)) {
42  if (avio_r8(s->pb) == 0x1a)
43  break;
44  }
45  if (avio_r8(s->pb) != 1)
46  return AVERROR_INVALIDDATA;
47  length = avio_r8(s->pb);
48  avio_skip(s->pb, length);
49  avio_skip(s->pb, 4);
50  depth = avio_r8(s->pb);
51 
52  st = avformat_new_stream(s, NULL);
53  if (!st)
54  return AVERROR(ENOMEM);
55 
57  st->codecpar->channels = 1;
58  st->codecpar->sample_rate = avio_rl32(s->pb);
59  switch (depth) {
60  case 8:
62  break;
63  case 16:
65  break;
66  case 24:
68  break;
69  case 32:
71  break;
72  default:
73  return AVERROR_INVALIDDATA;
74  }
75  avio_skip(s->pb, 16);
76  st->codecpar->block_align = depth / 8;
77 
78  return 0;
79 }
80 
82  .name = "sdx",
83  .long_name = NULL_IF_CONFIG_SMALL("Sample Dump eXchange"),
84  .read_probe = sdx_probe,
85  .read_header = sdx_read_header,
86  .read_packet = ff_pcm_read_packet,
87  .read_seek = ff_pcm_read_seek,
88  .extensions = "sdx",
89  .flags = AVFMT_GENERIC_INDEX,
90 };
sdx_read_header
static int sdx_read_header(AVFormatContext *s)
Definition: sdxdec.c:35
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:724
pcm.h
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
ff_sdx_demuxer
const AVInputFormat ff_sdx_demuxer
Definition: sdxdec.c:81
AV_CODEC_ID_PCM_U24LE
@ AV_CODEC_ID_PCM_U24LE
Definition: codec_id.h:327
AVCodecParameters::channels
int channels
Audio only.
Definition: codec_par.h:166
AVFMT_GENERIC_INDEX
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:468
AVInputFormat
Definition: avformat.h:626
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:631
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
sdx_probe
static int sdx_probe(const AVProbeData *p)
Definition: sdxdec.c:28
AVFormatContext
Format I/O context.
Definition: avformat.h:1097
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:992
NULL
#define NULL
Definition: coverity.c:32
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
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
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:742
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
AV_RB32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_RB32
Definition: bytestream.h:96
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:616
AVCodecParameters::block_align
int block_align
Audio only.
Definition: codec_par.h:177
ff_pcm_read_packet
int ff_pcm_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: pcm.c:29
AVStream
Stream structure.
Definition: avformat.h:845
ff_pcm_read_seek
int ff_pcm_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: pcm.c:56
avformat.h
AV_CODEC_ID_PCM_U32LE
@ AV_CODEC_ID_PCM_U32LE
Definition: codec_id.h:323
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:333
AV_CODEC_ID_PCM_U8
@ AV_CODEC_ID_PCM_U8
Definition: codec_id.h:318
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
AV_CODEC_ID_PCM_U16LE
@ AV_CODEC_ID_PCM_U16LE
Definition: codec_id.h:315
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
avstring.h
avio_feof
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:360