FFmpeg  4.4
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 };
Main libavformat public API header.
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:451
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:463
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:364
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:337
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:750
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:624
#define AV_RB32
Definition: intreadwrite.h:130
#define s(width, name)
Definition: cbs_vp9.c:257
#define NULL
Definition: coverity.c:32
@ AV_CODEC_ID_PCM_U8
Definition: codec_id.h:318
@ AV_CODEC_ID_PCM_U32LE
Definition: codec_id.h:323
@ AV_CODEC_ID_PCM_U24LE
Definition: codec_id.h:327
@ AV_CODEC_ID_PCM_U16LE
Definition: codec_id.h:315
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4505
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
#define AVERROR(e)
Definition: error.h:43
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
int ff_pcm_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: pcm.c:29
int ff_pcm_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: pcm.c:56
common internal API header
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
static int sdx_read_header(AVFormatContext *s)
Definition: sdxdec.c:35
AVInputFormat ff_sdx_demuxer
Definition: sdxdec.c:81
static int sdx_probe(const AVProbeData *p)
Definition: sdxdec.c:28
int channels
Audio only.
Definition: codec_par.h:166
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
int block_align
Audio only.
Definition: codec_par.h:177
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
int sample_rate
Audio only.
Definition: codec_par.h:170
Format I/O context.
Definition: avformat.h:1232
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:645
This structure contains the data a format has to probe a file.
Definition: avformat.h:441
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:443
Stream structure.
Definition: avformat.h:873
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1038