FFmpeg
vocenc.c
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1 /*
2  * Creative Voice File muxer.
3  * Copyright (c) 2006 Aurelien Jacobs <aurel@gnuage.org>
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 "voc.h"
23 #include "internal.h"
24 
25 
26 typedef struct voc_enc_context {
28 } VocEncContext;
29 
31 {
32  AVIOContext *pb = s->pb;
33  AVCodecParameters *par = s->streams[0]->codecpar;
34  const int header_size = 26;
35  const int version = 0x0114;
36 
37  if (s->nb_streams != 1
38  || s->streams[0]->codecpar->codec_type != AVMEDIA_TYPE_AUDIO)
39  return AVERROR_PATCHWELCOME;
40 
41  if (!par->codec_tag && par->codec_id != AV_CODEC_ID_PCM_U8) {
42  av_log(s, AV_LOG_ERROR, "unsupported codec\n");
43  return AVERROR(EINVAL);
44  }
45 
46  avio_write(pb, ff_voc_magic, sizeof(ff_voc_magic) - 1);
47  avio_wl16(pb, header_size);
48  avio_wl16(pb, version);
49  avio_wl16(pb, ~version + 0x1234);
50 
51  return 0;
52 }
53 
55 {
56  VocEncContext *voc = s->priv_data;
57  AVCodecParameters *par = s->streams[0]->codecpar;
58  AVIOContext *pb = s->pb;
59 
60  if (!voc->param_written) {
61  if (par->codec_tag > 3) {
63  avio_wl24(pb, pkt->size + 12);
64  avio_wl32(pb, par->sample_rate);
66  avio_w8(pb, par->ch_layout.nb_channels);
67  avio_wl16(pb, par->codec_tag);
68  avio_wl32(pb, 0);
69  } else {
70  if (s->streams[0]->codecpar->ch_layout.nb_channels > 1) {
72  avio_wl24(pb, 4);
73  avio_wl16(pb, 65536 - (256000000 + par->sample_rate * par->ch_layout.nb_channels / 2) /
74  (par->sample_rate * par->ch_layout.nb_channels));
75  avio_w8(pb, par->codec_tag);
76  avio_w8(pb, par->ch_layout.nb_channels - 1);
77  }
79  avio_wl24(pb, pkt->size + 2);
80  avio_w8(pb, 256 - (1000000 + par->sample_rate/2) / par->sample_rate);
81  avio_w8(pb, par->codec_tag);
82  }
83  voc->param_written = 1;
84  } else {
86  avio_wl24(pb, pkt->size);
87  }
88 
89  avio_write(pb, pkt->data, pkt->size);
90  return 0;
91 }
92 
94 {
95  avio_w8(s->pb, 0);
96  return 0;
97 }
98 
100  .name = "voc",
101  .long_name = NULL_IF_CONFIG_SMALL("Creative Voice"),
102  .mime_type = "audio/x-voc",
103  .extensions = "voc",
104  .priv_data_size = sizeof(VocEncContext),
105  .audio_codec = AV_CODEC_ID_PCM_S16LE,
106  .video_codec = AV_CODEC_ID_NONE,
110  .codec_tag = ff_voc_codec_tags_list,
112 };
voc_write_trailer
static int voc_write_trailer(AVFormatContext *s)
Definition: vocenc.c:93
AV_CODEC_ID_PCM_S16LE
@ AV_CODEC_ID_PCM_S16LE
Definition: codec_id.h:324
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
This struct describes the properties of an encoded stream.
Definition: codec_par.h:53
AVFMT_NOTIMESTAMPS
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:481
AVPacket::data
uint8_t * data
Definition: packet.h:374
AVCodecParameters::codec_tag
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:65
voc_enc_context::param_written
int param_written
Definition: vocenc.c:27
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:303
voc_write_header
static int voc_write_header(AVFormatContext *s)
Definition: vocenc.c:30
avio_wl16
void avio_wl16(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:466
pkt
AVPacket * pkt
Definition: movenc.c:59
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
ff_voc_magic
const unsigned char ff_voc_magic[21]
s
#define s(width, name)
Definition: cbs_vp9.c:256
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
VOC_TYPE_VOICE_DATA
@ VOC_TYPE_VOICE_DATA
Definition: voc.h:35
AVFormatContext
Format I/O context.
Definition: avformat.h:1216
ff_voc_codec_tags_list
const AVCodecTag *const ff_voc_codec_tags_list[]
internal.h
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:64
write_trailer
static int write_trailer(AVFormatContext *s1)
Definition: v4l2enc.c:100
VOC_TYPE_EXTENDED
@ VOC_TYPE_EXTENDED
Definition: voc.h:42
VOC_TYPE_VOICE_DATA_CONT
@ VOC_TYPE_VOICE_DATA_CONT
Definition: voc.h:36
avio_w8
void avio_w8(AVIOContext *s, int b)
Definition: aviobuf.c:210
ff_voc_muxer
const AVOutputFormat ff_voc_muxer
Definition: vocenc.c:99
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:212
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:177
AVIOContext
Bytestream IO Context.
Definition: avio.h:162
AVPacket::size
int size
Definition: packet.h:375
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:115
avio_write
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:232
avio_wl32
void avio_wl32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:386
version
version
Definition: libkvazaar.c:313
voc.h
voc_write_packet
static int voc_write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: vocenc.c:54
AV_CODEC_ID_NONE
@ AV_CODEC_ID_NONE
Definition: codec_id.h:50
AVOutputFormat
Definition: avformat.h:509
VOC_TYPE_NEW_VOICE_DATA
@ VOC_TYPE_NEW_VOICE_DATA
Definition: voc.h:43
voc_enc_context
Definition: vocenc.c:26
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:103
AV_CODEC_ID_PCM_U8
@ AV_CODEC_ID_PCM_U8
Definition: codec_id.h:329
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:61
AVPacket
This structure stores compressed data.
Definition: packet.h:351
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
avio_wl24
void avio_wl24(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:478
write_header
static void write_header(FFV1Context *f)
Definition: ffv1enc.c:346
write_packet
static int write_packet(OutputFile *of, OutputStream *ost, AVPacket *pkt)
Definition: ffmpeg_mux.c:90