FFmpeg: libavformat/ircamdec.c Source File

FFmpeg
ircamdec.c
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1 /*
2  * IRCAM demuxer
3  * Copyright (c) 2012 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/intreadwrite.h"
23 #include "libavcodec/internal.h"
24 #include "avformat.h"
25 #include "internal.h"
26 #include "pcm.h"
27 #include "ircam.h"
28 
29  static int ircam_probe(AVProbeData *p)
30 {
31  if ((p->buf[0] == 0x64 && p->buf[1] == 0xA3 && p->buf[3] == 0x00 &&
32  p->buf[2] >= 1 && p->buf[2] <= 4) ||
33  (p->buf[3] == 0x64 && p->buf[2] == 0xA3 && p->buf[0] == 0x00 &&
34  p->buf[1] >= 1 && p->buf[1] <= 3) &&
35  AV_RN32(p->buf + 4) && AV_RN32(p->buf + 8))
36  return AVPROBE_SCORE_MAX / 4 * 3;
37  return 0;
38 }
39 
40  static const struct endianess {
41   uint32_t magic;
42   int is_le;
43 } table[] = {
44  { 0x64A30100, 0 },
45  { 0x64A30200, 1 },
46  { 0x64A30300, 0 },
47  { 0x64A30400, 1 },
48  { 0x0001A364, 1 },
49  { 0x0002A364, 0 },
50  { 0x0003A364, 1 },
51 };
52 
53  static int ircam_read_header(AVFormatContext *s)
54 {
55  uint32_t magic, sample_rate, channels, tag;
56  const AVCodecTag *tags;
57  int le = -1, i;
58  AVStream *st;
59 
60  magic = avio_rl32(s->pb);
61  for (i = 0; i < 7; i++) {
62  if (magic == table[i].magic) {
63  le = table[i].is_le;
64  break;
65  }
66  }
67 
68  if (le == 1) {
69  sample_rate = av_int2float(avio_rl32(s->pb));
70  channels = avio_rl32(s->pb);
71  tag = avio_rl32(s->pb);
72  tags = ff_codec_ircam_le_tags;
73  } else if (le == 0) {
74  sample_rate = av_int2float(avio_rb32(s->pb));
75  channels = avio_rb32(s->pb);
76  tag = avio_rb32(s->pb);
77  tags = ff_codec_ircam_be_tags;
78  } else {
79  return AVERROR_INVALIDDATA;
80  }
81 
82  if (!channels || !sample_rate)
83  return AVERROR_INVALIDDATA;
84 
85  st = avformat_new_stream(s, NULL);
86  if (!st)
87  return AVERROR(ENOMEM);
88 
89  st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
90  st->codecpar->channels = channels;
91  if (st->codecpar->channels > FF_SANE_NB_CHANNELS)
92  return AVERROR(ENOSYS);
93  st->codecpar->sample_rate = sample_rate;
94 
95  st->codecpar->codec_id = ff_codec_get_id(tags, tag);
96  if (st->codecpar->codec_id == AV_CODEC_ID_NONE) {
97  av_log(s, AV_LOG_ERROR, "unknown tag %"PRIx32"\n", tag);
98  return AVERROR_INVALIDDATA;
99  }
100 
101  st->codecpar->bits_per_coded_sample = av_get_bits_per_sample(st->codecpar->codec_id);
102  st->codecpar->block_align = st->codecpar->bits_per_coded_sample * st->codecpar->channels / 8;
103  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
104  avio_skip(s->pb, 1008);
105 
106  return 0;
107 }
108 
109  AVInputFormat ff_ircam_demuxer = {
110  .name = "ircam",
111  .long_name = NULL_IF_CONFIG_SMALL("Berkeley/IRCAM/CARL Sound Format"),
112  .read_probe = ircam_probe,
113  .read_header = ircam_read_header,
114  .read_packet = ff_pcm_read_packet,
115  .read_seek = ff_pcm_read_seek,
116  .extensions = "sf,ircam",
117  .flags = AVFMT_GENERIC_INDEX,
118 };
FF_SANE_NB_CHANNELS
#define FF_SANE_NB_CHANNELS
Definition: internal.h:86
ff_ircam_demuxer
AVInputFormat ff_ircam_demuxer
Definition: ircamdec.c:109
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_NONE
Definition: avcodec.h:216
ff_codec_ircam_be_tags
const AVCodecTag ff_codec_ircam_be_tags[]
Definition: ircam.c:37
ff_codec_get_id
enum AVCodecID ff_codec_get_id(const AVCodecTag *tags, unsigned int tag)
Definition: utils.c:3117
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:4820
av_int2float
static av_always_inline float av_int2float(uint32_t i)
Reinterpret a 32-bit integer as a float.
Definition: intfloat.h:40
channels
channels
Definition: aptx.c:30
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
ircam_read_header
static int ircam_read_header(AVFormatContext *s)
Definition: ircamdec.c:53
AVFormatContext
Format I/O context.
Definition: avformat.h:1342
avio_rb32
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:801
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4450
tag
uint32_t tag
Definition: movenc.c:1455
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
ff_codec_ircam_le_tags
const AVCodecTag ff_codec_ircam_le_tags[]
Definition: ircam.c:25
endianess::magic
uint32_t magic
Definition: ircamdec.c:41
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
av_get_bits_per_sample
int av_get_bits_per_sample(enum AVCodecID codec_id)
Return codec bits per sample.
Definition: utils.c:1495
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:770
AVERROR
#define AVERROR(e)
Definition: error.h:43
table
static const struct endianess table[]
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
ircam_probe
static int ircam_probe(AVProbeData *p)
Definition: ircamdec.c:29
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
ff_pcm_read_packet
int ff_pcm_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: pcm.c:29
sample_rate
sample_rate
Definition: ffmpeg_filter.c:190
AVFormatContext::pb
AVIOContext * pb
I/O context.
Definition: avformat.h:1384
AVFMT_GENERIC_INDEX
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:470
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:448
AV_RN32
#define AV_RN32(p)
Definition: intreadwrite.h:364
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: avcodec.h:3994
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:460
avformat.h
Main libavformat public API header.
internal.h
common internal api header.
endianess::is_le
int is_le
Definition: ircamdec.c:42
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: avcodec.h:3926
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
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