FFmpeg
g723_1.c
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1 /*
2  * G.723.1 demuxer
3  * Copyright (c) 2010 Mohamed Naufal Basheer
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 /**
23  * @file
24  * G.723.1 demuxer
25  */
26 
27 #include "libavutil/attributes.h"
29 #include "avformat.h"
30 #include "internal.h"
31 
32 static const uint8_t frame_size[4] = { 24, 20, 4, 1 };
33 
35 {
36  AVStream *st;
37 
38  st = avformat_new_stream(s, NULL);
39  if (!st)
40  return AVERROR(ENOMEM);
41 
45  st->codecpar->channels = 1;
46  st->codecpar->sample_rate = 8000;
47 
48  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
49  st->start_time = 0;
50 
51  return 0;
52 }
53 
55 {
56  int size, byte, ret;
57 
58  pkt->pos = avio_tell(s->pb);
59  byte = avio_r8(s->pb);
60  size = frame_size[byte & 3];
61 
62  ret = av_new_packet(pkt, size);
63  if (ret < 0)
64  return ret;
65 
66  pkt->data[0] = byte;
67  pkt->duration = 240;
68  pkt->stream_index = 0;
69 
70  ret = avio_read(s->pb, pkt->data + 1, size - 1);
71  if (ret < size - 1) {
72  av_packet_unref(pkt);
73  return ret < 0 ? ret : AVERROR_EOF;
74  }
75 
76  return pkt->size;
77 }
78 
80  .name = "g723_1",
81  .long_name = NULL_IF_CONFIG_SMALL("G.723.1"),
82  .read_header = g723_1_init,
83  .read_packet = g723_1_read_packet,
84  .extensions = "tco,rco,g723_1",
85  .flags = AVFMT_GENERIC_INDEX
86 };
#define NULL
Definition: coverity.c:32
static int g723_1_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: g723_1.c:54
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1497
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:4882
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3953
int size
Definition: avcodec.h:1478
static AVPacket pkt
static const uint8_t frame_size[4]
Definition: g723_1.c:32
Macro definitions for various function/variable attributes.
Format I/O context.
Definition: avformat.h:1358
uint8_t
#define av_cold
Definition: attributes.h:82
AVInputFormat ff_g723_1_demuxer
Definition: g723_1.c:79
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: avcodec.h:1495
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4455
uint8_t * data
Definition: avcodec.h:1477
#define AVERROR_EOF
End of file.
Definition: error.h:55
ptrdiff_t size
Definition: opengl_enc.c:100
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
uint64_t channel_layout
Audio only.
Definition: avcodec.h:4055
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:648
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:86
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3949
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:639
audio channel layout utility functions
#define s(width, name)
Definition: cbs_vp9.c:257
Stream structure.
Definition: avformat.h:881
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_WB24 unsigned int_TMPL AV_WB16 unsigned int_TMPL byte
Definition: bytestream.h:87
AVIOContext * pb
I/O context.
Definition: avformat.h:1400
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:599
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:468
int sample_rate
Audio only.
Definition: avcodec.h:4063
Main libavformat public API header.
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base...
Definition: avformat.h:920
static av_cold int g723_1_init(AVFormatContext *s)
Definition: g723_1.c:34
int channels
Audio only.
Definition: avcodec.h:4059
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:654
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1028
int stream_index
Definition: avcodec.h:1479
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
#define AV_CH_LAYOUT_MONO
This structure stores compressed data.
Definition: avcodec.h:1454