MS Speech Platform 11 Recognizer 是否支持 ARPA 编译语法？

Question

如何在 MS Speech 中使用 ARPA 文件？ Microsoft Speech Platform 11 Recognizer 的文档暗示可以从 ARPA 文件编译语法。

我能够编译一个 ARPA 文件——例如，小例子 provided by Microsoft——使用以下命令行：

CompileGrammar.exe -In stock.arpa -InFormat ARPA

我能够在以下测试中使用生成的 CFG 文件：

using Microsoft.Speech.Recognition;

// ...

using (var engine = new SpeechRecognitionEngine(new CultureInfo("en-US")))
{
    engine.LoadGrammar(new Grammar("stock.cfg"));
    var result = engine.EmulateRecognize("will stock go up");
    Assert.That(result, Is.Not.Null);
}

此测试通过，但请注意它使用 EmulateRecognize()。当我切换到使用实际的音频文件时，如下所示：

using (var engine = new SpeechRecognitionEngine(new CultureInfo("en-US"))) 
{
    engine.LoadGrammar(new Grammar("stock.cfg"));
    engine.SetInputToWaveFile("go-up.wav");
    var result = engine.Recognize();
}

结果始终为空，测试失败。

Microsoft states quite clearly 它受支持，但即使是非常简单的示例似乎也不起作用。我做错了什么？

Answer 1

对于您的问题：

Does the MS Speech Platform 11 Recognizer support ARPA compiled grammars?

答案是肯定的。

我这边的工作代码，只需更改三个属性：Culture/Grammar/WaveFile。我不知道你的完整代码，但根据我的测试和演示代码，我猜根本原因是我们需要处理我们这边的 SpeechRecognized，而你可能还没有完成你的身边。

static bool completed;

        static void Main(string[] args)  
        {
            // Initialize an in-process speech recognition engine.  
            using (SpeechRecognitionEngine recognizer =
               new SpeechRecognitionEngine(new CultureInfo("en-us")))
            {

                // Create and load a grammar.   
                Grammar dictation = new Grammar("stock.cfg");
                dictation.Name = "Dictation Grammar";

                recognizer.LoadGrammar(dictation);

                // Configure the input to the recognizer.  
                recognizer.SetInputToWaveFile("test.wav");

                // Attach event handlers for the results of recognition.  
                recognizer.SpeechRecognized +=
                  new EventHandler<SpeechRecognizedEventArgs>(recognizer_SpeechRecognized);
                recognizer.RecognizeCompleted +=
                  new EventHandler<RecognizeCompletedEventArgs>(recognizer_RecognizeCompleted);

                // Perform recognition on the entire file.  
                Console.WriteLine("Starting asynchronous recognition...");
                completed = false;
                recognizer.RecognizeAsync();

                // Keep the console window open.  
                while (!completed)
                {
                    Console.ReadLine();
                }
                Console.WriteLine("Done.");
            }

            Console.WriteLine();
            Console.WriteLine("Press any key to exit...");
            Console.ReadKey();
        }

        // Handle the SpeechRecognized event.  
        static void recognizer_SpeechRecognized(object sender, SpeechRecognizedEventArgs e)
        {
            if (e.Result != null && e.Result.Text != null)
            {
                Console.WriteLine("  Recognized text =  {0}", e.Result.Text);
            }
            else
            {
                Console.WriteLine("  Recognized text not available.");
            }
        }

        // Handle the RecognizeCompleted event.  
        static void recognizer_RecognizeCompleted(object sender, RecognizeCompletedEventArgs e)
        {
            if (e.Error != null)
            {
                Console.WriteLine("  Error encountered, {0}: {1}",
                e.Error.GetType().Name, e.Error.Message);
            }
            if (e.Cancelled)
            {
                Console.WriteLine("  Operation cancelled.");
            }
            if (e.InputStreamEnded)
            {
                Console.WriteLine("  End of stream encountered.");
            }
            completed = true;
        }

而wav的内容就是“will stock go up”（时长约2秒）

For more infomation: https://docs.microsoft.com/en-us/dotnet/api/system.speech.recognition.speechrecognitionengine.setinputtowavefile?redirectedfrom=MSDN&view=netframework-4.7.2#System_Speech_Recognition_SpeechRecognitionEngine_SetInputToWaveFile_System_String_

Answer 2

这个问题有两种不同的答案，具体取决于您使用的 Microsoft Speech SDK 版本。 （参见：System.Speech.Recognition 和 Microsoft.Speech.Recognition 有什么区别？ )

System.Speech（桌面版）

在这种情况下，请参阅 。那里的示例代码很好用。

Microsoft.Speech（服务器版本）

可能因为服务器版本不包含 "dictation engine,"，Microsoft.Speech 库显然永远不会 匹配 ARPA 来源的 CFG。但是，它仍然会假设 通过 SpeechRecognitionRejected 事件所说的内容。以下是 seiya1223 桌面代码的必要更改：

1. 当然，将您的 using 语句从 System.Speech 更改为 Microsoft.Speech。
2. 为 SpeechRecognitionRejected 事件添加事件处理程序。
3. 在您的事件处理程序中，检查 e.Result.Text 属性 以获得最终假设。

以下代码片段有助于说明：

static string transcription;

static void Main(string[] args)  
{
  using (var recognizer = new SpeechRecognitionEngine(new CultureInfo("en-us")))
  {
    engine.SpeechRecognitionRejected += SpeechRecognitionRejectedHandler;
    // ...
  }
}

void SpeechRecognitionRejectedHandler(object sender, SpeechRecognitionRejectedEventArgs e)
{
  if (e.Result != null && !string.IsNullOrEmpty(e.Result.Text))
    transcription = e.Result.Text;
}

该处理程序在识别结束时调用一次。例如，这是 seiya1223 代码的输出，但使用了所有可用的事件处理程序和一堆额外的日志记录（强调我的）：

Starting asynchronous recognition...
In SpeechDetectedHandler:
- AudioPosition = 00:00:01.2300000
In SpeechHypothesizedHandler:
- Grammar Name = Stock; Result Text = Go
In SpeechHypothesizedHandler:
- Grammar Name = Stock; Result Text = will
In SpeechHypothesizedHandler:
- Grammar Name = Stock; Result Text = will Stock
In SpeechHypothesizedHandler:
- Grammar Name = Stock; Result Text = will Stock Go
In SpeechHypothesizedHandler:
- Grammar Name = Stock; Result Text = will Stock Go Up
In SpeechRecognitionRejectedHandler:
- Grammar Name = Stock; Result Text = will Stock Go Up
In RecognizeCompletedHandler.
- AudioPosition = 00:00:03.2000000; InputStreamEnded = True
- No result.
Done.