昨日のブログで、
Windows.Media.SpeechSynthesis Namespace
なんじゃ、これ？？？
と書きました。
矢張り気になったのでこの英文サイトの概要を見て、SpeechSynthesizerクラスを見るとSAPIのTTSのようです。この名前空間に関連するGitHubにあるサンプルのうち、Speechメソッド関連を除いてみると末尾にある通りで、（Visual Studio用のコードですが）赤字で書いた"using Windows..."系のDLLは（Microsoft.NETフォールダーをいくら調べても）私の環境になく、Visual Studioで提供されるライブラリーが無くては使えないことが分かりました。まぁ、これは無視、ですね。
また、System.Speech.dllでSynthesizerクラスのVoiceプロパティに選択される、音声音源のコレクションは、HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Speech\Voices
にあるHaruka、Zira、Davidの3名で、
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Speech_OneCore\Voices\Tokens
にあるその他の方の音声音源は使えないようです。（これに関わる詳細はBCCForm and BCCSkeltonのサンプル、"TextToSpeech"のヘルプファイルの「付録」を参照してください。）
そんなこんなでウロウロしていたら、昔読んだ記事で目からうろこでした。成程、WinRTでしたか。更に調べてみるとこんな話も。そうか！System32フォールダーか！ということでWindows.Media.SpeechSynthesis.dllを探したのですが見当たりません。Windows.Media.Speech.dllはあるので、この中にひょっとして（望み薄．．．）あればと昔読んだ記事のプログラムをコンパイルしてみると、
fatal error CS0009: 'c:\Windows\System32\Windows.Media.Speech.dll' メタデータ ファイルを開けませんでした -- '間違ったフォーマットのプログラムを読み込もうとしました。 '
というエラーが出て力尽きました。まぁ、私は"System.Speech"で細々と凌いでゆきましょう。
【Scenario_SynthesizeText.xaml.cs】
//*********************************************************
//
// Copyright (c) Microsoft. All rights reserved.
// This code is licensed under the MIT License (MIT).
// THIS CODE IS PROVIDED *AS IS* WITHOUT WARRANTY OF
// ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING ANY
// IMPLIED WARRANTIES OF FITNESS FOR A PARTICULAR
// PURPOSE, MERCHANTABILITY, OR NON-INFRINGEMENT.
//
//*********************************************************
using System;
using System.Linq;
using Windows.ApplicationModel.Resources.Core;
using Windows.Globalization;
using Windows.Media.SpeechSynthesis;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using Windows.UI.Xaml.Media;
namespace SDKTemplate
{
public sealed partial class Scenario_SynthesizeText : Page
{
private SpeechSynthesizer synthesizer;
private ResourceContext speechContext;
private ResourceMap speechResourceMap;
public Scenario_SynthesizeText()
{
InitializeComponent();
synthesizer = new SpeechSynthesizer();
speechContext = ResourceContext.GetForCurrentView();
speechContext.Languages = new string[] { SpeechSynthesizer.DefaultVoice.Language };
speechResourceMap = ResourceManager.Current.MainResourceMap.GetSubtree("LocalizationTTSResources");
InitializeListboxVoiceChooser();
}
/// <summary>
/// This is invoked when the user clicks on the speak/stop button.
/// </summary>
/// <param name="sender">Button that triggered this event</param>
/// <param name="e">State information about the routed event</param>
private async void Speak_Click(object sender, RoutedEventArgs e)
{
// If the media is playing, the user has pressed the button to stop the playback.
if (media.CurrentState == MediaElementState.Playing)
{
media.Stop();
btnSpeak.Content = "Speak";
}
else
{
string text = textToSynthesize.Text;
if (!String.IsNullOrEmpty(text))
{
// Change the button label. You could also just disable the button if you don't want any user control.
btnSpeak.Content = "Stop";
try
{
// Create a stream from the text. This will be played using a media element.
SpeechSynthesisStream synthesisStream = await synthesizer.SynthesizeTextToStreamAsync(text);
// Set the source and start playing the synthesized audio stream.
media.AutoPlay = true;
media.SetSource(synthesisStream, synthesisStream.ContentType);
media.Play();
}
catch (System.IO.FileNotFoundException)
{
// If media player components are unavailable, (eg, using a N SKU of windows), we won't
// be able to start media playback. Handle this gracefully
btnSpeak.Content = "Speak";
btnSpeak.IsEnabled = false;
textToSynthesize.IsEnabled = false;
listboxVoiceChooser.IsEnabled = false;
var messageDialog = new Windows.UI.Popups.MessageDialog("Media player components unavailable");
await messageDialog.ShowAsync();
}
catch (Exception)
{
// If the text is unable to be synthesized, throw an error message to the user.
btnSpeak.Content = "Speak";
media.AutoPlay = false;
var messageDialog = new Windows.UI.Popups.MessageDialog("Unable to synthesize text");
await messageDialog.ShowAsync();
}
}
}
}
/// <summary>
/// This is invoked when the stream is finished playing.
/// </summary>
/// <remarks>
/// In this case, we're changing the button label based on the state.
/// </remarks>
/// <param name="sender">unused object parameter</param>
/// <param name="e">unused event parameter</param>
void media_MediaEnded(object sender, RoutedEventArgs e)
{
btnSpeak.Content = "Speak";
}
/// <summary>
/// This creates items out of the system installed voices. The voices are then displayed in a listbox.
/// This allows the user to change the voice of the synthesizer in your app based on their preference.
/// </summary>
private void InitializeListboxVoiceChooser()
{
// Get all of the installed voices.
var voices = SpeechSynthesizer.AllVoices;
// Get the currently selected voice.
VoiceInformation currentVoice = synthesizer.Voice;
foreach (VoiceInformation voice in voices.OrderBy(p=>p.Language))
{
ComboBoxItem item = new ComboBoxItem();
item.Name = voice.DisplayName;
item.Tag = voice;
item.Content = voice.DisplayName + " (Language: " + voice.Language + ")";
listboxVoiceChooser.Items.Add(item);
// Check to see if we're looking at the current voice and set it as selected in the listbox.
if (currentVoice.Id == voice.Id)
{
item.IsSelected = true;
listboxVoiceChooser.SelectedItem = item;
}
}
}
/// <summary>
/// This is called when the user has selects a voice from the drop down.
/// </summary>
/// <param name="sender">unused object parameter</param>
/// <param name="e">unused event parameter</param>
private void ListboxVoiceChooser_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
ComboBoxItem item = (ComboBoxItem)(listboxVoiceChooser.SelectedItem);
VoiceInformation voice = (VoiceInformation)(item.Tag);
synthesizer.Voice = voice;
// update UI text to be an appropriate default translation.
speechContext.Languages = new string[] { voice.Language };
textToSynthesize.Text = speechResourceMap.GetValue("SynthesizeTextDefaultText", speechContext).ValueAsString;
}
}
}