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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  AVCodecContext *enc = s->streams[0]->codec;
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 (!enc->codec_tag && enc->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  AVCodecContext *enc = s->streams[0]->codec;
58  AVIOContext *pb = s->pb;
59 
60  if (!voc->param_written) {
61  if (enc->codec_tag > 3) {
63  avio_wl24(pb, pkt->size + 12);
64  avio_wl32(pb, enc->sample_rate);
66  avio_w8(pb, enc->channels);
67  avio_wl16(pb, enc->codec_tag);
68  avio_wl32(pb, 0);
69  } else {
70  if (s->streams[0]->codec->channels > 1) {
72  avio_wl24(pb, 4);
73  avio_wl16(pb, 65536-(256000000 + enc->sample_rate*enc->channels/2)/(enc->sample_rate*enc->channels));
74  avio_w8(pb, enc->codec_tag);
75  avio_w8(pb, enc->channels - 1);
76  }
78  avio_wl24(pb, pkt->size + 2);
79  avio_w8(pb, 256 - (1000000 + enc->sample_rate/2) / enc->sample_rate);
80  avio_w8(pb, enc->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 };