FFmpeg  4.4
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 #include "rawenc.h"
25 
26 static const char mode20_header[] = "#!iLBC20\n";
27 static const char mode30_header[] = "#!iLBC30\n";
28 
30 {
31  AVIOContext *pb = s->pb;
32  AVCodecParameters *par;
33 
34  if (s->nb_streams != 1) {
35  av_log(s, AV_LOG_ERROR, "Unsupported number of streams\n");
36  return AVERROR(EINVAL);
37  }
38  par = s->streams[0]->codecpar;
39 
40  if (par->codec_id != AV_CODEC_ID_ILBC) {
41  av_log(s, AV_LOG_ERROR, "Unsupported codec\n");
42  return AVERROR(EINVAL);
43  }
44 
45  if (par->block_align == 50) {
46  avio_write(pb, mode30_header, sizeof(mode30_header) - 1);
47  } else if (par->block_align == 38) {
48  avio_write(pb, mode20_header, sizeof(mode20_header) - 1);
49  } else {
50  av_log(s, AV_LOG_ERROR, "Unsupported mode\n");
51  return AVERROR(EINVAL);
52  }
53  return 0;
54 }
55 
56 static int ilbc_probe(const AVProbeData *p)
57 {
58  // Only check for "#!iLBC" which matches both formats
59  if (!memcmp(p->buf, mode20_header, 6))
60  return AVPROBE_SCORE_MAX;
61  else
62  return 0;
63 }
64 
66 {
67  AVIOContext *pb = s->pb;
68  AVStream *st;
69  uint8_t header[9];
70 
71  avio_read(pb, header, 9);
72 
73  st = avformat_new_stream(s, NULL);
74  if (!st)
75  return AVERROR(ENOMEM);
77  st->codecpar->sample_rate = 8000;
78  st->codecpar->channels = 1;
80  st->start_time = 0;
81  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
82  if (!memcmp(header, mode20_header, sizeof(mode20_header) - 1)) {
83  st->codecpar->block_align = 38;
84  st->codecpar->bit_rate = 15200;
85  } else if (!memcmp(header, mode30_header, sizeof(mode30_header) - 1)) {
86  st->codecpar->block_align = 50;
87  st->codecpar->bit_rate = 13333;
88  } else {
89  av_log(s, AV_LOG_ERROR, "Unrecognized iLBC file header\n");
90  return AVERROR_INVALIDDATA;
91  }
92 
93  return 0;
94 }
95 
97  AVPacket *pkt)
98 {
99  AVCodecParameters *par = s->streams[0]->codecpar;
100  int ret;
101 
102  if ((ret = av_new_packet(pkt, par->block_align)) < 0)
103  return ret;
104 
105  pkt->stream_index = 0;
106  pkt->pos = avio_tell(s->pb);
107  pkt->duration = par->block_align == 38 ? 160 : 240;
108  if ((ret = avio_read(s->pb, pkt->data, par->block_align)) != par->block_align) {
109  return ret < 0 ? ret : AVERROR(EIO);
110  }
111 
112  return 0;
113 }
114 
116  .name = "ilbc",
117  .long_name = NULL_IF_CONFIG_SMALL("iLBC storage"),
118  .read_probe = ilbc_probe,
119  .read_header = ilbc_read_header,
120  .read_packet = ilbc_read_packet,
121  .flags = AVFMT_GENERIC_INDEX,
122 };
123 
124 #if CONFIG_ILBC_MUXER
126  .name = "ilbc",
127  .long_name = NULL_IF_CONFIG_SMALL("iLBC storage"),
128  .mime_type = "audio/iLBC",
129  .extensions = "lbc",
130  .audio_codec = AV_CODEC_ID_ILBC,
131  .write_header = ilbc_write_header,
132  .write_packet = ff_raw_write_packet,
133  .flags = AVFMT_NOTIMESTAMPS,
134 };
135 #endif
AVOutputFormat ff_ilbc_muxer
uint8_t
Main libavformat public API header.
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:453
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:463
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:462
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:633
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:225
#define s(width, name)
Definition: cbs_vp9.c:257
#define NULL
Definition: coverity.c:32
@ AV_CODEC_ID_ILBC
Definition: codec_id.h:483
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:99
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4505
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
#define AVERROR(e)
Definition: error.h:43
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
static int ilbc_write_header(AVFormatContext *s)
Definition: ilbc.c:29
static const char mode20_header[]
Definition: ilbc.c:26
static int ilbc_read_header(AVFormatContext *s)
Definition: ilbc.c:65
static int ilbc_probe(const AVProbeData *p)
Definition: ilbc.c:56
static const char mode30_header[]
Definition: ilbc.c:27
AVInputFormat ff_ilbc_demuxer
Definition: ilbc.c:115
static int ilbc_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: ilbc.c:96
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:4941
int ff_raw_write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: rawenc.c:29
common internal API header
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
static const uint8_t header[24]
Definition: sdr2.c:67
This struct describes the properties of an encoded stream.
Definition: codec_par.h:52
int channels
Audio only.
Definition: codec_par.h:166
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:89
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
int block_align
Audio only.
Definition: codec_par.h:177
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
int sample_rate
Audio only.
Definition: codec_par.h:170
Format I/O context.
Definition: avformat.h:1232
Bytestream IO Context.
Definition: avio.h:161
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:645
const char * name
Definition: avformat.h:491
This structure stores compressed data.
Definition: packet.h:346
int stream_index
Definition: packet.h:371
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:387
uint8_t * data
Definition: packet.h:369
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:389
This structure contains the data a format has to probe a file.
Definition: avformat.h:441
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:443
Stream structure.
Definition: avformat.h:873
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1038
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base.
Definition: avformat.h:912
#define av_log(a,...)
AVPacket * pkt
Definition: movenc.c:59