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ilbc.c
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1 /*
2  * iLBC storage file format
3  * Copyright (c) 2012 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 "avformat.h"
23 #include "internal.h"
24 
25 static const char mode20_header[] = "#!iLBC20\n";
26 static const char mode30_header[] = "#!iLBC30\n";
27 
29 {
30  AVIOContext *pb = s->pb;
31  AVCodecParameters *par;
32 
33  if (s->nb_streams != 1) {
34  av_log(s, AV_LOG_ERROR, "Unsupported number of streams\n");
35  return AVERROR(EINVAL);
36  }
37  par = s->streams[0]->codecpar;
38 
39  if (par->codec_id != AV_CODEC_ID_ILBC) {
40  av_log(s, AV_LOG_ERROR, "Unsupported codec\n");
41  return AVERROR(EINVAL);
42  }
43 
44  if (par->block_align == 50) {
45  avio_write(pb, mode30_header, sizeof(mode30_header) - 1);
46  } else if (par->block_align == 38) {
47  avio_write(pb, mode20_header, sizeof(mode20_header) - 1);
48  } else {
49  av_log(s, AV_LOG_ERROR, "Unsupported mode\n");
50  return AVERROR(EINVAL);
51  }
52  avio_flush(pb);
53  return 0;
54 }
55 
57 {
58  avio_write(s->pb, pkt->data, pkt->size);
59  return 0;
60 }
61 
62 static int ilbc_probe(AVProbeData *p)
63 {
64  // Only check for "#!iLBC" which matches both formats
65  if (!memcmp(p->buf, mode20_header, 6))
66  return AVPROBE_SCORE_MAX;
67  else
68  return 0;
69 }
70 
72 {
73  AVIOContext *pb = s->pb;
74  AVStream *st;
75  uint8_t header[9];
76 
77  avio_read(pb, header, 9);
78 
79  st = avformat_new_stream(s, NULL);
80  if (!st)
81  return AVERROR(ENOMEM);
83  st->codecpar->sample_rate = 8000;
84  st->codecpar->channels = 1;
86  st->start_time = 0;
87  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
88  if (!memcmp(header, mode20_header, sizeof(mode20_header) - 1)) {
89  st->codecpar->block_align = 38;
90  st->codecpar->bit_rate = 15200;
91  } else if (!memcmp(header, mode30_header, sizeof(mode30_header) - 1)) {
92  st->codecpar->block_align = 50;
93  st->codecpar->bit_rate = 13333;
94  } else {
95  av_log(s, AV_LOG_ERROR, "Unrecognized iLBC file header\n");
96  return AVERROR_INVALIDDATA;
97  }
98 
99  return 0;
100 }
101 
103  AVPacket *pkt)
104 {
105  AVCodecParameters *par = s->streams[0]->codecpar;
106  int ret;
107 
108  if ((ret = av_new_packet(pkt, par->block_align)) < 0)
109  return ret;
110 
111  pkt->stream_index = 0;
112  pkt->pos = avio_tell(s->pb);
113  pkt->duration = par->block_align == 38 ? 160 : 240;
114  if ((ret = avio_read(s->pb, pkt->data, par->block_align)) != par->block_align) {
115  av_packet_unref(pkt);
116  return ret < 0 ? ret : AVERROR(EIO);
117  }
118 
119  return 0;
120 }
121 
123  .name = "ilbc",
124  .long_name = NULL_IF_CONFIG_SMALL("iLBC storage"),
125  .read_probe = ilbc_probe,
126  .read_header = ilbc_read_header,
127  .read_packet = ilbc_read_packet,
128  .flags = AVFMT_GENERIC_INDEX,
129 };
130 
132  .name = "ilbc",
133  .long_name = NULL_IF_CONFIG_SMALL("iLBC storage"),
134  .mime_type = "audio/iLBC",
135  .extensions = "lbc",
136  .audio_codec = AV_CODEC_ID_ILBC,
137  .write_header = ilbc_write_header,
138  .write_packet = ilbc_write_packet,
139  .flags = AVFMT_NOTIMESTAMPS,
140 };
#define NULL
Definition: coverity.c:32
static const char mode30_header[]
Definition: ilbc.c:26
const char * s
Definition: avisynth_c.h:768
Bytestream IO Context.
Definition: avio.h:147
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1620
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:4549
static int ilbc_read_header(AVFormatContext *s)
Definition: ilbc.c:71
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3979
int size
Definition: avcodec.h:1601
static AVPacket pkt
This struct describes the properties of an encoded stream.
Definition: avcodec.h:3971
Format I/O context.
Definition: avformat.h:1330
static int ilbc_probe(AVProbeData *p)
Definition: ilbc.c:62
uint8_t
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: avcodec.h:1618
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4182
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1398
uint8_t * data
Definition: avcodec.h:1600
AVInputFormat ff_ilbc_demuxer
Definition: ilbc.c:122
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:511
static const uint8_t header[24]
Definition: sdr2.c:67
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:204
#define av_log(a,...)
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:604
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: avcodec.h:4008
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 AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#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
static int ilbc_write_header(AVFormatContext *s)
Definition: ilbc.c:28
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3975
AVOutputFormat ff_ilbc_muxer
Definition: ilbc.c:131
static int ilbc_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: ilbc.c:102
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:463
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1386
int block_align
Audio only.
Definition: avcodec.h:4096
static int ilbc_write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: ilbc.c:56
int void avio_flush(AVIOContext *s)
Force flushing of buffered data.
Definition: aviobuf.c:224
const char * name
Definition: avformat.h:524
Stream structure.
Definition: avformat.h:881
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:486
AVIOContext * pb
I/O context.
Definition: avformat.h:1372
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:567
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:487
This structure contains the data a format has to probe a file.
Definition: avformat.h:461
int sample_rate
Audio only.
Definition: avcodec.h:4089
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:473
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:928
static const char mode20_header[]
Definition: ilbc.c:25
int channels
Audio only.
Definition: avcodec.h:4085
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:662
AVCodecParameters * codecpar
Definition: avformat.h:1233
int stream_index
Definition: avcodec.h:1602
This structure stores compressed data.
Definition: avcodec.h:1577