Voice Synthesis with a uC - Audio File IP Available?

[berkeman]

Voice Synthesis with a uC -- Audio File IP Available?

I'm working on a project that will involve voice synthesis and playing simple tones using a mid-range 8-bit microcontroller (uC). I've done my own proprietary tone synthesis many years ago (with an 8051), but for this present project, I'd like to use some popular standard for the audio data files. The audio quality does not need to be CD music quality -- just reasonable voice and simple tones.

I've done a little searching for info on the standards, and searching for what is typically done with simple uCs for audio synthesis, but I'm not finding any great Rosetta stones so far. What do people generally do for voice synthesis on 8-bit uCs? What would be the right data format for me to plan on using, and what sample rate and data width (8-bits?) are typically used? Is compression always used for the stored data? If I want to get or purchase audio files to use, where should I go looking?

Thanks for any help!

 

[chroot]

Are you just looking to play back pre-recorded samples of audio? The easiest possible standard is WAV. Other than a small amount of header information, the entire file is nothing more than uncompressed samples.

Another pretty simple and common format would be au. You can get somewhat better audio for the same data rate.

Speech has very little meaningful content beyond 7 kHz or so, so you would not need to use any sample rates above 14 kHz. 8-bit resolution is probably entirely adequate for this application.

- Warren

 

[berkeman]

Thanks chroot. I'll check out the links tomorrow when I'm back at work.