1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
|
/*
* Copyright (C) 2019-2021 Yomichan Authors
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
/* global
* TextToSpeechAudio
*/
class AudioSystem {
constructor() {
this._fallbackAudio = null;
}
prepare() {
// speechSynthesis.getVoices() will not be populated unless some API call is made.
if (typeof speechSynthesis === 'undefined') { return; }
const eventListeners = new EventListenerCollection();
const onVoicesChanged = () => { eventListeners.removeAllEventListeners(); };
eventListeners.addEventListener(speechSynthesis, 'voiceschanged', onVoicesChanged, false);
}
getFallbackAudio() {
if (this._fallbackAudio === null) {
this._fallbackAudio = new Audio('/data/audio/button.mp3');
}
return this._fallbackAudio;
}
createAudio(url, source) {
return new Promise((resolve, reject) => {
const audio = new Audio(url);
audio.addEventListener('loadeddata', () => {
if (!this._isAudioValid(audio, source)) {
reject(new Error('Could not retrieve audio'));
} else {
resolve(audio);
}
});
audio.addEventListener('error', () => reject(audio.error));
});
}
createTextToSpeechAudio(text, voiceUri) {
const voice = this._getTextToSpeechVoiceFromVoiceUri(voiceUri);
if (voice === null) {
throw new Error('Invalid text-to-speech voice');
}
return new TextToSpeechAudio(text, voice);
}
// Private
_isAudioValid(audio, source) {
switch (source) {
case 'jpod101':
{
const duration = audio.duration;
return (
duration !== 5.694694 && // Invalid audio (Chrome)
duration !== 5.720718 // Invalid audio (Firefox)
);
}
default:
return true;
}
}
_getTextToSpeechVoiceFromVoiceUri(voiceUri) {
try {
for (const voice of speechSynthesis.getVoices()) {
if (voice.voiceURI === voiceUri) {
return voice;
}
}
} catch (e) {
// NOP
}
return null;
}
}
|