BasicDSP is a program to apply simple Digital Signal Processing algorithms
to audio signals. The input can either be taken from the sound card, or
be a locally generated sine wave, white noise or impulse signal. The output
is fed to the sound card, as well as to a virtual oscilloscope and spectrum
The DSP algorithm itself is specified in a very straightforward programming
language which has only assignment statements (and on unix a print statement).
Each line contains one statement, and all lines are executed once for each
incoming sample. The input sample is available in variables named in,
output into variables named out, outl and/or outr.
Heres a simple example program:
a = a + slider1 * (in - a)
outl = a
outr = fir(in, 0.1, 0.3, 0.3, 0.1)
This illustrates defining new variables (a in the example), the use of
the sliders, and the use of a built-in function like fir().
The help-menu gives access to a complete list of built-in variables and
Note: the program was originally written to accompany a series of articles
on Software-Defined Radio appearing in the Dutch amateur radio journal
'Electron'. Another tutorial appeared in the December 2007 issue of SPRAT.