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 {
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
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->channels);
67  avio_wl16(pb, par->codec_tag);
68  avio_wl32(pb, 0);
69  } else {
70  if (s->streams[0]->codecpar->channels > 1) {
72  avio_wl24(pb, 4);
73  avio_wl16(pb, 65536-(256000000 + par->sample_rate*par->channels/2)/(par->sample_rate*par->channels));
74  avio_w8(pb, par->codec_tag);
75  avio_w8(pb, par->channels - 1);
76  }
78  avio_wl24(pb, pkt->size + 2);
79  avio_w8(pb, 256 - (1000000 + par->sample_rate/2) / par->sample_rate);
80  avio_w8(pb, par->codec_tag);
81  }
82  voc->param_written = 1;
83  } else {
85  avio_wl24(pb, pkt->size);
86  }
87 
88  avio_write(pb, pkt->data, pkt->size);
89  return 0;
90 }
91 
93 {
94  avio_w8(s->pb, 0);
95  return 0;
96 }
97 
99  .name = "voc",
100  .long_name = NULL_IF_CONFIG_SMALL("Creative Voice"),
101  .mime_type = "audio/x-voc",
102  .extensions = "voc",
103  .priv_data_size = sizeof(VocEncContext),
104  .audio_codec = AV_CODEC_ID_PCM_S16LE,
105  .video_codec = AV_CODEC_ID_NONE,
109  .codec_tag = (const AVCodecTag* const []){ ff_voc_codec_tags, 0 },
110  .flags = AVFMT_NOTIMESTAMPS,
111 };
static void write_packet(OutputFile *of, AVPacket *pkt, OutputStream *ost, int unqueue)
Definition: ffmpeg.c:689
void avio_wl16(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:469
Bytestream IO Context.
Definition: avio.h:161
int param_written
Definition: vocenc.c:27
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3953
int size
Definition: avcodec.h:1478
static int voc_write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: vocenc.c:54
int version
Definition: avisynth_c.h:858
static AVPacket pkt
This struct describes the properties of an encoded stream.
Definition: avcodec.h:3945
Format I/O context.
Definition: avformat.h:1358
void avio_wl32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:369
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1426
AVOutputFormat ff_voc_muxer
Definition: vocenc.c:98
uint8_t * data
Definition: avcodec.h:1477
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:218
#define av_log(a,...)
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3949
static int voc_write_trailer(AVFormatContext *s)
Definition: vocenc.c:92
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1414
static int write_trailer(AVFormatContext *s1)
Definition: v4l2enc.c:94
const char * name
Definition: avformat.h:505
#define s(width, name)
Definition: cbs_vp9.c:257
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:467
const AVCodecTag ff_voc_codec_tags[]
Definition: voc.c:27
AVIOContext * pb
I/O context.
Definition: avformat.h:1400
void avio_w8(AVIOContext *s, int b)
Definition: aviobuf.c:196
void avio_wl24(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:481
const unsigned char ff_voc_magic[21]
Definition: voc.c:25
int sample_rate
Audio only.
Definition: avcodec.h:4063
void * priv_data
Format private data.
Definition: avformat.h:1386
static void write_header(FFV1Context *f)
Definition: ffv1enc.c:337
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: avcodec.h:3995
int channels
Audio only.
Definition: avcodec.h:4059
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1028
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: avcodec.h:3957
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
static int voc_write_header(AVFormatContext *s)
Definition: vocenc.c:30
This structure stores compressed data.
Definition: avcodec.h:1454