FFmpeg: libavformat/sdxdec.c Source File

FFmpeg
sdxdec.c
Go to the documentation of this file.
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(AVProbeData *p)
29 {
30  if (AV_RB32(p->buf) == AV_RB32("SDX:"))
31  return AVPROBE_SCORE_EXTENSION;
32  return 0;
33 }
34 
35  static int sdx_read_header(AVFormatContext *s)
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 
56  st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
57  st->codecpar->channels = 1;
58  st->codecpar->sample_rate = avio_rl32(s->pb);
59  switch (depth) {
60  case 8:
61  st->codecpar->codec_id = AV_CODEC_ID_PCM_U8;
62  break;
63  case 16:
64  st->codecpar->codec_id = AV_CODEC_ID_PCM_U16LE;
65  break;
66  case 24:
67  st->codecpar->codec_id = AV_CODEC_ID_PCM_U24LE;
68  break;
69  case 32:
70  st->codecpar->codec_id = AV_CODEC_ID_PCM_U32LE;
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 
81  AVInputFormat ff_sdx_demuxer = {
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 };
NULL
#define NULL
Definition: coverity.c:32
s
const char * s
Definition: avisynth_c.h:768
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
AV_CODEC_ID_PCM_U16LE
Definition: avcodec.h:454
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3884
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:331
sdx_read_header
static int sdx_read_header(AVFormatContext *s)
Definition: sdxdec.c:35
AVFormatContext
Format I/O context.
Definition: avformat.h:1342
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4450
AV_CODEC_ID_PCM_U24LE
Definition: avcodec.h:466
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:87
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:770
AVERROR
#define AVERROR(e)
Definition: error.h:43
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:186
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3880
AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
length
GLsizei GLsizei * length
Definition: opengl_enc.c:115
ff_sdx_demuxer
AVInputFormat ff_sdx_demuxer
Definition: sdxdec.c:81
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:639
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:450
AVCodecParameters::block_align
int block_align
Audio only.
Definition: avcodec.h:4001
ff_pcm_read_seek
int ff_pcm_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: pcm.c:52
AVStream
Stream structure.
Definition: avformat.h:873
AV_CODEC_ID_PCM_U8
Definition: avcodec.h:457
ff_pcm_read_packet
int ff_pcm_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: pcm.c:29
AVFormatContext::pb
AVIOContext * pb
I/O context.
Definition: avformat.h:1384
sdx_probe
static int sdx_probe(AVProbeData *p)
Definition: sdxdec.c:28
AV_CODEC_ID_PCM_U32LE
Definition: avcodec.h:462
AVFMT_GENERIC_INDEX
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:470
AVPROBE_SCORE_EXTENSION
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:458
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:448
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: avcodec.h:3994
avformat.h
Main libavformat public API header.
AVCodecParameters::channels
int channels
Audio only.
Definition: avcodec.h:3990
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:647
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1020
avio_feof
int avio_feof(AVIOContext *s)
feof() equivalent for AVIOContext.
Definition: aviobuf.c:358
Generated on Sun May 13 2018 02:04:07 for FFmpeg by   doxygen 1.8.6

AltStyle によって変換されたページ (->オリジナル) /