Libav
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 Libav.
6  *
7  * Libav 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  * Libav 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 Libav; 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  const int header_size = 26;
34  const int version = 0x0114;
35 
36  if (s->nb_streams != 1
38  return AVERROR_PATCHWELCOME;
39 
40  avio_write(pb, ff_voc_magic, sizeof(ff_voc_magic) - 1);
41  avio_wl16(pb, header_size);
42  avio_wl16(pb, version);
43  avio_wl16(pb, ~version + 0x1234);
44 
45  return 0;
46 }
47 
49 {
50  VocEncContext *voc = s->priv_data;
51  AVCodecContext *enc = s->streams[0]->codec;
52  AVIOContext *pb = s->pb;
53 
54  if (!voc->param_written) {
55  if (enc->codec_tag > 0xFF) {
57  avio_wl24(pb, pkt->size + 12);
58  avio_wl32(pb, enc->sample_rate);
60  avio_w8(pb, enc->channels);
61  avio_wl16(pb, enc->codec_tag);
62  avio_wl32(pb, 0);
63  } else {
64  if (s->streams[0]->codec->channels > 1) {
66  avio_wl24(pb, 4);
67  avio_wl16(pb, 65536-256000000/(enc->sample_rate*enc->channels));
68  avio_w8(pb, enc->codec_tag);
69  avio_w8(pb, enc->channels - 1);
70  }
72  avio_wl24(pb, pkt->size + 2);
73  avio_w8(pb, 256 - 1000000 / enc->sample_rate);
74  avio_w8(pb, enc->codec_tag);
75  }
76  voc->param_written = 1;
77  } else {
79  avio_wl24(pb, pkt->size);
80  }
81 
82  avio_write(pb, pkt->data, pkt->size);
83  return 0;
84 }
85 
87 {
88  avio_w8(s->pb, 0);
89  return 0;
90 }
91 
93  .name = "voc",
94  .long_name = NULL_IF_CONFIG_SMALL("Creative Voice"),
95  .mime_type = "audio/x-voc",
96  .extensions = "voc",
97  .priv_data_size = sizeof(VocEncContext),
98  .audio_codec = AV_CODEC_ID_PCM_U8,
99  .video_codec = AV_CODEC_ID_NONE,
103  .codec_tag = (const AVCodecTag* const []){ ff_voc_codec_tags, 0 },
104  .flags = AVFMT_NOTIMESTAMPS,
105 };
Bytestream IO Context.
Definition: avio.h:68
int param_written
Definition: vocenc.c:27
static int write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: assenc.c:58
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:718
int size
Definition: avcodec.h:974
static int voc_write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: vocenc.c:48
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:165
Format I/O context.
Definition: avformat.h:922
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:416
void avio_wl32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:260
AVOutputFormat ff_voc_muxer
Definition: vocenc.c:92
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2507
static int write_trailer(AVFormatContext *s)
Definition: assenc.c:64
void * priv_data
Format private data.
Definition: avformat.h:950
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:150
static int voc_write_trailer(AVFormatContext *s)
Definition: vocenc.c:86
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:978
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:990
const char * name
Definition: avformat.h:446
void avio_w8(AVIOContext *s, int b)
Definition: aviobuf.c:144
#define AVERROR_PATCHWELCOME
Not yet implemented in Libav, patches welcome.
Definition: error.h:57
const AVCodecTag ff_voc_codec_tags[]
Definition: voc.c:27
enum AVMediaType codec_type
Definition: avcodec.h:1058
version
Definition: ffv1enc.c:1080
int sample_rate
samples per second
Definition: avcodec.h:1791
main external API structure.
Definition: avcodec.h:1050
unsigned int codec_tag
fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
Definition: avcodec.h:1082
AVIOContext * pb
I/O context.
Definition: avformat.h:964
uint8_t * data
Definition: avcodec.h:973
const unsigned char ff_voc_magic[21]
Definition: voc.c:25
void avio_wl24(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:348
int channels
number of audio channels
Definition: avcodec.h:1792
static void write_header(FFV1Context *f)
Definition: ffv1enc.c:380
static int voc_write_header(AVFormatContext *s)
Definition: vocenc.c:30
This structure stores compressed data.
Definition: avcodec.h:950
void avio_wl16(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:336