Tag Archives: Spectral envelope

Synthesis with Sinusoids

Analysis and re-synthesis of a wave using DFT (Discrete Fourier Synthesis) or FFT (Fast Fourier Synthesis) is fairly direct. Here’s a DFT routine in Lua that, given a buffer containing a single pitch period, will return function dft( buffer )   … Continue reading

Posted in Uncategorized | Tagged , , , | 2 Comments

GUI Programming in Lua

Most of the tools I’ve been writing run from the command line with no GUI. That’s generally not a problem because I can use tools like Praat to check the output. But some of the more recent things I’ve been … Continue reading

Posted in Development | Tagged , , , , , , , , | Leave a comment

Click and Buzz

While the prototype voice synthesis using spectral envelopes is encouraging, there are still a lot of issues left to resolve. I tracked down a “click” in the output to sudden transitions in amplitude between frames. Amplitude and frequency are now … Continue reading

Posted in Development | Tagged | Leave a comment

Low-Budget Spectral Envelopes

Some time back I’d written some Java code that attempted to create a rough spectral envelope by picking the n highest point in an FFT. It was moderately successful, but I eventually decided to take the project down the synthesis … Continue reading

Posted in Development | Tagged | 1 Comment

Grumble…

I’ve been trying to implement spectral morphing, but have run into a lot of problems. The morphing itself works pretty well – I can apply an envelope taken from one sound, and apply it to another with a fair amount … Continue reading

Posted in Uncategorized | Tagged , , , , , , , | Leave a comment

Implementing Spectral Envelope Morphs

I’ve done an initial implementation of crossfades via spectral morphs. There’s currently no support for pitch shifting, but that should be straight forward to add. Although it works well for some tests, for others I’m getting what sounds like loud … Continue reading

Posted in Uncategorized | Tagged , , , , , , | Leave a comment

Working on Morphing Spectral Envelopes

Having implemented spectral envelopes, it now makes sense to implement morphing of spectral envelopes to get a smooth interpolation between vowel sounds. But first, I needed to track down a bug in the shiny new SpectralEnvelope class, which was failing to produce … Continue reading

Posted in Uncategorized | Tagged , , | Leave a comment