Acoustic Models: Analysis/Resynthesis
a quick look at the Fourier Transform (more coming later!), and
some experiments with Linear Predictive Coding (LPC)
Links
- MiXViews sound editor
-- the mxv editing program by Doug Scott that we used for the
LPC analysis
- SPEAR
-- Michael Klingbeil's terrific FFT analysis program
- Fourier Transform
-- good set of programs and FFT links on an older class page
- digital filters
-- LPC is built upon source/filter theory; this is an older class web page
with some code and information about digital filters
- FFT modeling
-- an older class web page looking at various ways of modeling FFT data
- Sine-wave Speech
-- this shows the perceptual power of formants in our hearing, based on
work done by Columbia's (Barnard's) own
Robert Remez
(here is his
original research)
There is quite a bit of research and information on-line about LPC -- do
a google search for "LPC Sound Synthesis" and you will find a mountain
of information. One of the links that came up when I did a quick search
was to Perry Cook's book
Real Sound Synthesis for Interactive Applications,
which has some very lucid explanations of filter theory, DSP in general, etc.
Applications and Examples
Class patches:
- week7.sit
- week7.tar
- the LPC patches we did in class
- hibrad.aiff
- hibrad.lpc
- the audio file and LPC analysis file used in the class patches
[NOTE: the "dataset()" command in the scripts will need to reflect
where the lpc file is stored.]