Store and recall pyFFTW wisdom, so it runs fast every time.

[danielballan]

http://hgomersall.github.io/pyFFTW/sphinx/tutorial.html#quick-and-easy-the-pyfftw-interfaces-module

[danielballan]

Turning on the cache helps.

BEFORE:

bandpass single pre-loaded image
10 loops, best of 3: 63.4 ms per loop
batch locate frames
1 loops, best of 3: 14.2 s per loop

AFTER pyfftw.interfaces.cache.enabled():

bandpass single pre-loaded image
10 loops, best of 3: 47.2 ms per loop
batch locate frames
1 loops, best of 3: 13.9 s per loop