All the Cool Developers use Speech APIs : Text to Speech

Enumerating TTS Engines using System.Speech.Synthesizer

Charles Oppermann — Thu, 31 Jul 2008 00:48:21 GMT

Here is a quick and dirty C# console application that will list out the installed TTS engines and associated properties. Make sure you add System.Speech to your project's list of references.

using System;
using System.Collections.Generic;
using System.Speech;
using System.Speech.Synthesis;
using System.Speech.AudioFormat;

namespace SelectVoice
{
  class SelectVoice
  {
    static void Main(string[] args)
    {
      Console.WriteLine("SelectVoice Example");
      SpeechSynthesizer ttsSynth = new SpeechSynthesizer();

      Console.WriteLine("Listing installed speech synthesizer voices...");
      foreach (InstalledVoice ttsVoice in ttsSynth.GetInstalledVoices())
      {
        Console.WriteLine("Name:\t{0}", ttsVoice.VoiceInfo.Name);
        Console.WriteLine("Desc:\t{0}", ttsVoice.VoiceInfo.Description);
        Console.WriteLine("Id:\t{0}", ttsVoice.VoiceInfo.Id);
        Console.WriteLine("Gender:\t{0}", ttsVoice.VoiceInfo.Gender);
        Console.WriteLine("Age:\t{0}", ttsVoice.VoiceInfo.Age);

        Console.WriteLine("Supported Audio Formats:");
        foreach (SpeechAudioFormatInfo audioFormat in ttsVoice.VoiceInfo.SupportedAudioFormats)
        {
          Console.WriteLine("\tEncodingFormat:\t{0}", audioFormat.EncodingFormat);
          Console.WriteLine("\tChannelCount:\t{0}", audioFormat.ChannelCount);
          Console.WriteLine("\tBits/sec:\t{0}", audioFormat.BitsPerSample);
          Console.WriteLine("\tAvg Bytes/sec:\t{0}", audioFormat.AverageBytesPerSecond);
          Console.WriteLine("\tSamples/sec:\t{0}", audioFormat.SamplesPerSecond);
          Console.WriteLine("\tBlockAlign:\t{0}", audioFormat.BlockAlign);
        }

        Console.WriteLine("Additional Information:");
        foreach(KeyValuePair<string, string> kvp in ttsVoice.VoiceInfo.AdditionalInfo)
          Console.WriteLine("\t{0}:  {1}", kvp.Key, kvp.Value);
        Console.WriteLine();
      }
    Console.WriteLine("Finished listing installed voices.");

    ttsSynth.SelectVoice("Microsoft Anna");
    ttsSynth.Speak("Greetings, my name is " + ttsSynth.Voice.Name);
    }
  }
}

Speech Content in the Windows SDK

Charles Oppermann — Tue, 26 Feb 2008 12:46:00 GMT

I'm happy to announce the availability of the RTM release of the Windows SDK. This release - the first RTM one since Vista - contains the following speech-related items:

Updated: SAPI 5.3 documentation
Updated: System.Speech documentation
Updated: Sample source code

8 C++ projects
3 C# projects
2 sample engines - TTS and SR

New: Grammar Compiler (GC.EXE) tool now part of the tool binaries included in the SDK

The Windows SDK completely replaces the older SAPI 5.1 SDK and supports development on Windows XP, Windows Server 2003, Windows Vista, and Windows Server 2008.

Customers can download this SDK as a DVD image (1,330MB ISO file) from this location:
http://www.microsoft.com/downloads/details.aspx?FamilyId=F26B1AA4-741A-433A-9BE5-FA919850BDBF

Or go through a guided setup process where only the components they need are downloaded. Speech is part of the base install.
http://www.microsoft.com/downloads/details.aspx?FamilyId=E6E1C3DF-A74F-4207-8586-711EBE331CDC

I'm particularly interested in your feedback regarding the Windows SDK as a whole and in particular getting speech information.

Background on Audio Volume in Windows Vista

Charles Oppermann — Wed, 18 Apr 2007 19:33:16 GMT

Our friend in the multimedia group and prolific blogger Larry Osterman is writing a series of articles on how volume is treated in Windows Vista.

There is a whole new audio sub-system in Vista and Larry's blog is a great source of information for developers.

Volume in Windows Vista, part 1: What is "volume"?
Volume in Windows Vista, part 2: Types of volume in Windows Vista

Microsoft Speech API SDK

Charles Oppermann — Fri, 24 Nov 2006 20:58:21 GMT

The Speech API Software Developers Kit (SAPI SDK) contains the documentation, samples, and header and library files to create applications and utilities that use speech recognition and voice synthesis. In addition, the SAPI SDK can be used to create speech recognition and voice synthesis engines that can be used by other applications.

Generally, the version of SAPI is determined by the platform that shipped it. SAPI 5.1 was included with Windows XP along with the Microsoft Sam TTS engine. The initial release of Windows XP did not include a speech recognition engine. The Tablet PC Edition of Windows XP did include version 6.1 of Microsoft's speech recognition engine. This was also shipped with Office 2003. Office 2003 also included SAPI TTS voices from Lernout & Hauspie, called LH Michael and LH Michelle. Also note that some vendors include SR and TTS engines with their products. For example, my laptop came with speech recognition and TTS engine provided by Toshiba.

With Windows Vista, the version of SAPI that is installed is 5.3. We have replaced the Microsoft Sam voice with next generation technology in a new female voice we call Microsoft Anna. We have also made major improvements to the speech recognition engine (now version 8.0) and that is included in all editions of Windows Vista.

For the SDK, you can download the SAPI 5.1 SDK to create applications and engines that work on Windows XP and Windows Server 2003. These applications or engines should also be forward-compatible with SAPI 5.3 on Windows Vista and beyond. The SAPI 5.1 SDK is a stand-alone package, separate from other Microsoft SDK's.

With SAPI 5.3, we integrated our SDK into the main Windows SDK (sometimes known as the Platform SDK). You can use the Windows SDK to create applications for Windows Vista, Windows XP, and Windows Server 2003. What OS version you target is done at compile-time, and that prevents features that only exist in latter versions from being available.

You can get an ISO image to burn the SDK to a DVD here:

http://www.microsoft.com/downloads/details.aspx?familyid=7614FE22-8A64-4DFB-AA0C-DB53035F40A0

To selectively download and install various components of the Windows SDK, go here:

http://www.microsoft.com/downloads/details.aspx?FamilyId=C2B1E300-F358-4523-B479-F53D234CDCCF

Something else that is new is our Managed Speech API's. Codenamed SpeechFX, the Managed Speech API is part of the Microsoft .NET Framework 3.0. The new System.Speech namespace provides managed classes for speech recognition and synthesis. This makes it much easier to write speech applications from managed code, such as C# or Visual Basic .NET.

The Managed Speech API documentation is included with the Windows SDK. Applications that use .NET Framework 3.0 will work on Windows Vista, Windows XP and Windows Server 2003. Note that you have to redistribute the .NET Framework 3.0 with your application for Windows XP and Windows Server 2003. The framework is already included with Windows Vista.