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 file format"),
95  .mime_type = "audio/x-voc",
96  .extensions = "voc",
97  .priv_data_size = sizeof(VocEncContext),
98  .audio_codec = CODEC_ID_PCM_U8,
99  .video_codec = CODEC_ID_NONE,
103  .codec_tag=(const AVCodecTag* const []){ff_voc_codec_tags, 0},
104 };