Releases every cached FFT instance. The library keeps one FFT instance per
transform size to avoid rebuilding its lookup tables on each call; each
instance holds tables proportional to its size (≈1 MB for a 64k transform).
Call this to free that memory once you are done transforming — for example
after processing a batch of large spectra. Subsequent transforms simply
rebuild whatever sizes they need.
Releases every cached FFT instance. The library keeps one FFT instance per transform size to avoid rebuilding its lookup tables on each call; each instance holds tables proportional to its size (≈1 MB for a 64k transform). Call this to free that memory once you are done transforming — for example after processing a batch of large spectra. Subsequent transforms simply rebuild whatever sizes they need.