FFmpeg
g722.c
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1 /*
2  * g722 raw demuxer
3  * Copyright (c) 2010 Martin Storsjo
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/avassert.h"
23 #include "avformat.h"
24 #include "internal.h"
25 #include "rawdec.h"
26 
28 {
29  AVStream *st;
30 
31  st = avformat_new_stream(s, NULL);
32  if (!st)
33  return AVERROR(ENOMEM);
34 
37  st->codecpar->sample_rate = 16000;
38  st->codecpar->channels = 1;
39 
42 
44 
45  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
46  return 0;
47 }
48 
51  .name = "g722",
52  .long_name = NULL_IF_CONFIG_SMALL("raw G.722"),
53  .read_header = g722_read_header,
54  .read_packet = ff_raw_read_partial_packet,
55  .flags = AVFMT_GENERIC_INDEX,
56  .extensions = "g722,722",
57  .raw_codec_id = AV_CODEC_ID_ADPCM_G722,
58  .priv_data_size = sizeof(FFRawDemuxerContext),
59  .priv_class = &g722_demuxer_class,};
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: utils.c:4480
ff_g722_demuxer
AVInputFormat ff_g722_demuxer
Definition: g722.c:50
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3953
g722_read_header
static int g722_read_header(AVFormatContext *s)
Definition: g722.c:27
AV_CODEC_ID_ADPCM_G722
@ AV_CODEC_ID_ADPCM_G722
Definition: avcodec.h:530
AVCodecParameters::channels
int channels
Audio only.
Definition: avcodec.h:4063
FFRawDemuxerContext
Definition: rawdec.h:37
AVFMT_GENERIC_INDEX
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:468
avassert.h
AVInputFormat
Definition: avformat.h:640
ff_raw_read_partial_packet
int ff_raw_read_partial_packet(AVFormatContext *s, AVPacket *pkt)
Definition: rawdec.c:35
s
#define s(width, name)
Definition: cbs_vp9.c:257
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:645
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
av_assert0
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
AVFormatContext
Format I/O context.
Definition: avformat.h:1342
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1017
NULL
#define NULL
Definition: coverity.c:32
rawdec.h
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: avcodec.h:4067
av_get_bits_per_sample
int av_get_bits_per_sample(enum AVCodecID codec_id)
Return codec bits per sample.
Definition: utils.c:1550
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:188
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:4910
AVStream
Stream structure.
Definition: avformat.h:870
avformat.h
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: avcodec.h:3999
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3957
FF_RAW_DEMUXER_CLASS
#define FF_RAW_DEMUXER_CLASS(name)
Definition: rawdec.h:55