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  AVCodecContext *codec = s->streams[0]->codec;
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);
46  avio_wl32(s->pb, av_float2int(codec->sample_rate));
47  avio_wl32(s->pb, codec->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 };
const char * s
Definition: avisynth_c.h:668
static int ircam_write_header(AVFormatContext *s)
Definition: ircamenc.c:29
unsigned int ff_codec_get_tag(const AVCodecTag *tags, enum AVCodecID id)
Format I/O context.
Definition: avformat.h:944
void avio_wl32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:291
AVStream ** streams
Definition: avformat.h:992
uint32_t tag
Definition: movenc.c:894
const AVCodecTag ff_codec_ircam_le_tags[]
Definition: ircam.c:25
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:246
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:662
unsigned int nb_streams
A list of all streams in the file.
Definition: avformat.h:991
void ffio_fill(AVIOContext *s, int b, int count)
Definition: aviobuf.c:159
const char * name
Definition: avformat.h:378
int ff_raw_write_packet(AVFormatContext *s, AVPacket *pkt)
enum AVCodecID codec_id
int sample_rate
samples per second
AVIOContext * pb
I/O context.
Definition: avformat.h:977
main external API structure.
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:148
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFilterBuffer 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.Buffer references ownership and permissions
static av_always_inline uint32_t av_float2int(float f)
Reinterpret a float as a 32-bit integer.
Definition: intfloat.h:50
Main libavformat public API header.
AVOutputFormat ff_ircam_muxer
Definition: ircamenc.c:53
int channels
number of audio channels