TTS, or text-to-speech, is the digitized audio rendering of computer text into speech. TTS software can "read" text from a document, Web page or e-Book, generating synthesized speech through a computer's speakers.
TTS programs can be useful for a variety of applications. For example, proofreading with TTS allows the author to catch awkward phrases, missing words or pacing problems. TTS can also convert text files into audio MP3 files that can then be transferred to a portable MP3 player or CD-ROM. This can save time by allowing the user to listen to reports or background materials in bed, en route to a meeting, or while performing other tasks.
Even top screenwriting software includes TTS functionality so that a writer can assign different voices to characters in his or her script. The writer can then listen to the dialog to weed out stilted sentences. There are also personal uses for TTS. Behind on reading your email or favorite blogs? Listen to TTS files while you work out, jog, clean the house, or take the dog for a walk.
In the area of education, TTS programs provide a valuable edge, particularly for learning new languages. Speech engines are available in a variety of languages, including English, Spanish, German, French, and dozens more.
TTS makes a critical difference to those with disabilities such as poor vision or visual dyslexia. People with speech loss can utilize specialized TTS programs to turn typed words into vocalization, as does renowned astrophysicist Dr. Steven Hawking. Afflicted with Amyotrophic Lateral Sclerosis (ALS), Hawking retains use of just two fingers which he uses with a proprietary interface. In March 2004, NeoSpeech's VoiceText™ became Hawking's new TTS voice.
Software programs vary in quality, as do speech engines. Artificial voices can sound very robotic or quite natural. Microsoft's Windows XP includes a basic built-in TTS engine that can be upgraded with free online downloads.
Third party TTS programs can allow for great flexibility and, in many cases, much-improved voice quality. Most of these affordable programs come with a variety of voices to choose from, both male and female. Some offer voices with accents. For specialized fields of vocabulary such as medical terminology, a medical TTS program is required.
TTS vocalization has come a long way and will continue to improve. The art of designing software that can provide context-dependent pronunciation and inflection is a highly complicated, code-intensive task. Before purchasing a TTS program, listen to samples of the digitized voice(s). Unnatural sounding voices will distract from content and may be unsuitable for some purposes. Search engines will reveal a multitude of programs to choose from.