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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
const char * s
Definition: avisynth_c.h:631
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1600
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:4436
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3922
int size
Definition: avcodec.h:1581
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:1325
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:1598
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4074
uint8_t * data
Definition: avcodec.h:1580
#define AVERROR_EOF
End of file.
Definition: error.h:55
ptrdiff_t size
Definition: opengl_enc.c:101
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:511
uint64_t channel_layout
Audio only.
Definition: avcodec.h:4024
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:598
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 AVERROR(e)
Definition: error.h:43
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3918
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:589
audio channel layout utility functions
Stream structure.
Definition: avformat.h:876
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:1367
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:563
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:485
int sample_rate
Audio only.
Definition: avcodec.h:4032
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:923
static av_cold int g723_1_init(AVFormatContext *s)
Definition: g723_1.c:34
int channels
Audio only.
Definition: avcodec.h:4028
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:660
AVCodecParameters * codecpar
Definition: avformat.h:1228
int stream_index
Definition: avcodec.h:1582
#define AV_CH_LAYOUT_MONO
This structure stores compressed data.
Definition: avcodec.h:1557