jurihock / sdft

Single file forward and inverse Sliding DFT in C, C++ and Python
MIT License
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Control latency via Fourier time-shifting property #3

Closed jurihock closed 1 year ago

jurihock commented 2 years ago

The note in "Sliding DFT for Fun and Musical Profit" is misleading:

A zero latency version is more expensive, and while we have had it implemented in our experimental code it seems rather too much.

There is no such thing like "zero latency" due to windowing. The amplitude of the first/last sample is suppressed by the window function in the time domain. Consequently "zero latency" means "zero amplitude". Applying circular shift before proper windowing is quite pointless.