ha7ilm / csdr

A simple DSP library and command-line tool for Software Defined Radio.
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FFT improvements #19

Closed tejeez closed 8 years ago

tejeez commented 8 years ago

I found the FFT function spent most of CPU time calling window function than calculating the FFT. This was fixed by calculating the window only once when csdr starts.

Additionally, I implemented logaveragepower_cf which works like logpower_cf but averages power from multiple successive FFTs before taking the logarithm. This is useful for making better looking waterfall displays in openwebrx.