ou may have noticed that synthesized voices are becoming more commonplace. Hundreds, if not thousands of electronic toys and gadgets speak to their owners in robotic voices. Whether it is a talking baby doll, a talking pedometer, or a new automated telephone system, several products that use text to speech are released every day.
Text-to-Speech (TTS), also known as speech synthesis, is the process in which typed text is transformed into audible speech. This is preferable to pre-recorded text in which it must be known ahead of time exactly what must be said. With text-to-speech there are opportunities to introduce information that is dynamic. The dynamic information could be from a database or a case where text spoken by a user is repeated for confirmation.
Experimenting with Text-to-speech
If you have never seen (or rather, heard) text-to-speech in action, you may want to download a free copy of ReadPlease 2003
. The product reads text from the Windows clipboard. To use it, you simply paste some text into the ReadPlease editor (see Figure 1
) andassuming your PC speakers are turned onyou'll hear the text spoken back to you. Currently, the product only works with all Windows desktop OSs, versions, but there are plans to release versions for Mac, Unix, Palm, and Windows CE operating systems as well.
The interesting thing about the ReadPlease application is that you can use the ReadPlease editor to experiment with your text-to-speech preferences. For example, you can adjust the speed in which text is spoken by moving the Speed slider control seen in Figure 1
up and down. You can also change the voice used by clicking the arrow buttons underneath the face picture icon.
|What You Need
|Visual Studio .NET 2003, Microsoft Speech Application SDK, 1.1
|Figure 1. The ReadPlease 2003 Application: This Windows application reads any text pasted into the edit field from the clipboard.|
Clicking the Tools menu and then selecting Options allows you to experiment further with the text-to-speech editor, adjusting how long the speech engine pauses between paragraphs for example. Upgrading to the ReadPlease Plus version gives you access to additional options such as a pronunciation editor, which lets you specify how a particular word will be pronounced. The ReadPlease Plus version also includes a taskbar you can dock at the top of your Windows Desktop. So, you can quickly drag text from any text-based application into the taskbar and have it read to you.
By default, the ReadPlease application uses the built-in Microsoft voices (Mark, Mike, Sam, or Marilyn). But, you can optionally purchase higher-quality AT&T Natural Voices, such as those in the AT&T Natural Voices Starter Pack ($25.00 US). The Starter Pack includes the 8K versions of "Mike" and "Crystal," both of which sound much better than the default Microsoft voices.
|Author's Note: The term 8K means that the sample rate used to create the wave file occurred at 8000 bits per second. Another format is 16k which results in a clearer and more natural sounding voice. Basically the higher the sample rate, the better the voice quality.
If you're interested, you can hear a sample of these and other voices