FFmpeg
ircamenc.c
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1 /*
2  * IRCAM muxer
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 "avformat.h"
24 #include "avio_internal.h"
25 #include "internal.h"
26 #include "rawenc.h"
27 #include "ircam.h"
28 
30 {
31  AVCodecParameters *par = s->streams[0]->codecpar;
32  uint32_t tag;
33 
34  if (s->nb_streams != 1) {
35  av_log(s, AV_LOG_ERROR, "only one stream is supported\n");
36  return AVERROR(EINVAL);
37  }
38 
40  if (!tag) {
41  av_log(s, AV_LOG_ERROR, "unsupported codec\n");
42  return AVERROR(EINVAL);
43  }
44 
45  avio_wl32(s->pb, 0x0001A364);
47  avio_wl32(s->pb, par->channels);
48  avio_wl32(s->pb, tag);
49  ffio_fill(s->pb, 0, 1008);
50  return 0;
51 }
52 
54  .name = "ircam",
55  .extensions = "sf,ircam",
56  .long_name = NULL_IF_CONFIG_SMALL("Berkeley/IRCAM/CARL Sound Format"),
57  .audio_codec = AV_CODEC_ID_PCM_S16LE,
58  .video_codec = AV_CODEC_ID_NONE,
59  .write_header = ircam_write_header,
60  .write_packet = ff_raw_write_packet,
61  .codec_tag = (const AVCodecTag *const []){ ff_codec_ircam_le_tags, 0 },
62 };
static int ircam_write_header(AVFormatContext *s)
Definition: ircamenc.c:29
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3953
unsigned int ff_codec_get_tag(const AVCodecTag *tags, enum AVCodecID id)
Definition: utils.c:3115
This struct describes the properties of an encoded stream.
Definition: avcodec.h:3945
uint32_t av_q2intfloat(AVRational q)
Convert an AVRational to a IEEE 32-bit float expressed in fixed-point format.
Definition: rational.c:152
Format I/O context.
Definition: avformat.h:1358
void avio_wl32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:369
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1426
uint32_t tag
Definition: movenc.c:1496
#define av_log(a,...)
const AVCodecTag ff_codec_ircam_le_tags[]
Definition: ircam.c:25
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1414
void ffio_fill(AVIOContext *s, int b, int count)
Definition: aviobuf.c:204
const char * name
Definition: avformat.h:505
#define s(width, name)
Definition: cbs_vp9.c:257
int ff_raw_write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: rawenc.c:29
AVIOContext * pb
I/O context.
Definition: avformat.h:1400
Rational number (pair of numerator and denominator).
Definition: rational.h:58
int sample_rate
Audio only.
Definition: avcodec.h:4063
Main libavformat public API header.
AVOutputFormat ff_ircam_muxer
Definition: ircamenc.c:53
int channels
Audio only.
Definition: avcodec.h:4059
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1028
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