FFmpeg
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 "config_components.h"
23 
24 #include "avformat.h"
25 #include "demux.h"
26 #include "internal.h"
27 #include "mux.h"
28 #include "rawenc.h"
29 
30 static const char mode20_header[] = "#!iLBC20\n";
31 static const char mode30_header[] = "#!iLBC30\n";
32 
34 {
35  AVIOContext *pb = s->pb;
36  AVCodecParameters *par = s->streams[0]->codecpar;
37 
38  if (par->block_align == 50) {
39  avio_write(pb, mode30_header, sizeof(mode30_header) - 1);
40  } else if (par->block_align == 38) {
41  avio_write(pb, mode20_header, sizeof(mode20_header) - 1);
42  } else {
43  av_log(s, AV_LOG_ERROR, "Unsupported mode\n");
44  return AVERROR(EINVAL);
45  }
46  return 0;
47 }
48 
49 static int ilbc_probe(const AVProbeData *p)
50 {
51  // Only check for "#!iLBC" which matches both formats
52  if (!memcmp(p->buf, mode20_header, 6))
53  return AVPROBE_SCORE_MAX;
54  else
55  return 0;
56 }
57 
59 {
60  AVIOContext *pb = s->pb;
61  AVStream *st;
62  uint8_t header[9];
63 
64  avio_read(pb, header, 9);
65 
66  st = avformat_new_stream(s, NULL);
67  if (!st)
68  return AVERROR(ENOMEM);
70  st->codecpar->sample_rate = 8000;
73  st->start_time = 0;
74  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
75  if (!memcmp(header, mode20_header, sizeof(mode20_header) - 1)) {
76  st->codecpar->block_align = 38;
77  st->codecpar->bit_rate = 15200;
78  } else if (!memcmp(header, mode30_header, sizeof(mode30_header) - 1)) {
79  st->codecpar->block_align = 50;
80  st->codecpar->bit_rate = 13333;
81  } else {
82  av_log(s, AV_LOG_ERROR, "Unrecognized iLBC file header\n");
83  return AVERROR_INVALIDDATA;
84  }
85 
86  return 0;
87 }
88 
90  AVPacket *pkt)
91 {
92  AVCodecParameters *par = s->streams[0]->codecpar;
93  int ret;
94 
95  if ((ret = av_get_packet(s->pb, pkt, par->block_align)) != par->block_align)
96  return ret < 0 ? ret : AVERROR_INVALIDDATA;
97 
98  pkt->stream_index = 0;
99  pkt->duration = par->block_align == 38 ? 160 : 240;
100 
101  return 0;
102 }
103 
105  .p.name = "ilbc",
106  .p.long_name = NULL_IF_CONFIG_SMALL("iLBC storage"),
107  .p.flags = AVFMT_GENERIC_INDEX,
108  .read_probe = ilbc_probe,
109  .read_header = ilbc_read_header,
110  .read_packet = ilbc_read_packet,
111 };
112 
113 #if CONFIG_ILBC_MUXER
115  .p.name = "ilbc",
116  .p.long_name = NULL_IF_CONFIG_SMALL("iLBC storage"),
117  .p.mime_type = "audio/iLBC",
118  .p.extensions = "lbc",
119  .p.video_codec = AV_CODEC_ID_NONE,
120  .p.audio_codec = AV_CODEC_ID_ILBC,
121  .p.subtitle_codec = AV_CODEC_ID_NONE,
122  .p.flags = AVFMT_NOTIMESTAMPS,
123  .flags_internal = FF_OFMT_FLAG_MAX_ONE_OF_EACH |
125  .write_header = ilbc_write_header,
126  .write_packet = ff_raw_write_packet,
127 };
128 #endif
AVOutputFormat::name
const char * name
Definition: avformat.h:510
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
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:51
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:47
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const struct AVCodec *c)
Add a new stream to a media file.
ilbc_probe
static int ilbc_probe(const AVProbeData *p)
Definition: ilbc.c:49
AVFMT_NOTIMESTAMPS
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:479
ilbc_write_header
static int ilbc_write_header(AVFormatContext *s)
Definition: ilbc.c:33
AVPacket::duration
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:538
FF_OFMT_FLAG_ONLY_DEFAULT_CODECS
#define FF_OFMT_FLAG_ONLY_DEFAULT_CODECS
If this flag is set, then the only permitted audio/video/subtitle codec ids are AVOutputFormat....
Definition: mux.h:59
FFOutputFormat::p
AVOutputFormat p
The public AVOutputFormat.
Definition: mux.h:65
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:463
avpriv_set_pts_info
void avpriv_set_pts_info(AVStream *st, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: avformat.c:853
ff_ilbc_muxer
const FFOutputFormat ff_ilbc_muxer
AVFMT_GENERIC_INDEX
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:480
mode30_header
static const char mode30_header[]
Definition: ilbc.c:31
pkt
AVPacket * pkt
Definition: movenc.c:60
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
s
#define s(width, name)
Definition: cbs_vp9.c:198
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:553
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:453
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
ff_raw_write_packet
int ff_raw_write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: rawenc.c:31
AVFormatContext
Format I/O context.
Definition: avformat.h:1255
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:766
NULL
#define NULL
Definition: coverity.c:32
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:451
FFOutputFormat
Definition: mux.h:61
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:180
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:184
AVIOContext
Bytestream IO Context.
Definition: avio.h:160
ff_ilbc_demuxer
const FFInputFormat ff_ilbc_demuxer
Definition: ilbc.c:104
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:94
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:311
mode20_header
static const char mode20_header[]
Definition: ilbc.c:30
FFInputFormat::p
AVInputFormat p
The public AVInputFormat.
Definition: demux.h:41
header
static const uint8_t header[24]
Definition: sdr2.c:68
avio_write
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:201
rawenc.h
AV_CODEC_ID_NONE
@ AV_CODEC_ID_NONE
Definition: codec_id.h:50
AVCodecParameters::block_align
int block_align
Audio only.
Definition: codec_par.h:191
FF_OFMT_FLAG_MAX_ONE_OF_EACH
#define FF_OFMT_FLAG_MAX_ONE_OF_EACH
If this flag is set, it indicates that for each codec type whose corresponding default codec (i....
Definition: mux.h:50
demux.h
av_get_packet
int av_get_packet(AVIOContext *s, AVPacket *pkt, int size)
Allocate and read the payload of a packet and initialize its fields with default values.
Definition: utils.c:91
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:743
avformat.h
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:612
ilbc_read_packet
static int ilbc_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: ilbc.c:89
AVPacket::stream_index
int stream_index
Definition: packet.h:522
AV_CHANNEL_LAYOUT_MONO
#define AV_CHANNEL_LAYOUT_MONO
Definition: channel_layout.h:386
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:55
AVPacket
This structure stores compressed data.
Definition: packet.h:497
FFInputFormat
Definition: demux.h:37
AV_CODEC_ID_ILBC
@ AV_CODEC_ID_ILBC
Definition: codec_id.h:499
AVCodecParameters::bit_rate
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:97
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
AVStream::start_time
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base.
Definition: avformat.h:792
ilbc_read_header
static int ilbc_read_header(AVFormatContext *s)
Definition: ilbc.c:58
mux.h