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(const 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 = lrintf(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 = lrintf(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->ch_layout.nb_channels = channels;
91  if (st->codecpar->ch_layout.nb_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 *
103  st->codecpar->ch_layout.nb_channels / 8;
104  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
105  avio_skip(s->pb, 1008);
106 
107  return 0;
108 }
109 
110  const AVInputFormat ff_ircam_demuxer = {
111  .name = "ircam",
112  .long_name = NULL_IF_CONFIG_SMALL("Berkeley/IRCAM/CARL Sound Format"),
113  .read_probe = ircam_probe,
114  .read_header = ircam_read_header,
115  .read_packet = ff_pcm_read_packet,
116  .read_seek = ff_pcm_read_seek,
117  .extensions = "sf,ircam",
118  .flags = AVFMT_GENERIC_INDEX,
119 };
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: options.c:243
pcm.h
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:58
internal.h
endianess::magic
uint32_t magic
Definition: ircamdec.c:41
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:311
sample_rate
sample_rate
Definition: ffmpeg_filter.c:156
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:463
avpriv_set_pts_info
void avpriv_set_pts_info(AVStream *st, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: avformat.c:771
av_int2float
static av_always_inline float av_int2float(uint32_t i)
Reinterpret a 32-bit integer as a float.
Definition: intfloat.h:40
ircam.h
AVFMT_GENERIC_INDEX
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:480
endianess
Definition: ircamdec.c:40
av_get_bits_per_sample
int av_get_bits_per_sample(enum AVCodecID codec_id)
Return codec bits per sample.
Definition: utils.c:583
avio_rb32
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:782
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
AVInputFormat
Definition: avformat.h:546
AVCodecTag
Definition: internal.h:49
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:256
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:551
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:453
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
channels
channels
Definition: aptx.h:31
ff_codec_ircam_le_tags
const AVCodecTag ff_codec_ircam_le_tags[]
Definition: ircam.c:25
AVFormatContext
Format I/O context.
Definition: avformat.h:1104
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:861
NULL
#define NULL
Definition: coverity.c:32
table
static const struct endianess table[]
AV_RN32
#define AV_RN32(p)
Definition: intreadwrite.h:364
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:451
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:213
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:178
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:751
ff_codec_ircam_be_tags
const AVCodecTag ff_codec_ircam_be_tags[]
Definition: ircam.c:37
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:115
ff_codec_get_id
enum AVCodecID ff_codec_get_id(const AVCodecTag *tags, unsigned int tag)
Definition: utils.c:144
ircam_probe
static int ircam_probe(const AVProbeData *p)
Definition: ircamdec.c:29
ircam_read_header
static int ircam_read_header(AVFormatContext *s)
Definition: ircamdec.c:53
ff_ircam_demuxer
const AVInputFormat ff_ircam_demuxer
Definition: ircamdec.c:110
lrintf
#define lrintf(x)
Definition: libm_mips.h:72
AV_CODEC_ID_NONE
@ AV_CODEC_ID_NONE
Definition: codec_id.h:50
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
AVCodecParameters::block_align
int block_align
Audio only.
Definition: codec_par.h:185
ff_pcm_read_packet
int ff_pcm_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: pcm.c:29
tag
uint32_t tag
Definition: movenc.c:1641
AVStream
Stream structure.
Definition: avformat.h:838
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
endianess::is_le
int is_le
Definition: ircamdec.c:42
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:339
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:104
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:62
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
FF_SANE_NB_CHANNELS
#define FF_SANE_NB_CHANNELS
Definition: internal.h:40
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