whitening

Value Members

1. object NormalizeEnergy

   

   Normalize the "energy" in a scalar field (which is assumed to be an image).

2. object WhitenNaturalImage

   

   Whiten a natural image.

   Whiten a natural image.

   Natural images have a power spectrum well approximated by 1 / f**2. This function flattens that spectrum to facilitate further processing. The algorithm is from Bruno Olshausen:

   http://redwood.berkeley.edu/bruno/npb261b/lab2/lab2.html

3. object WhiteningFilter extends MatlabFunctions with libcog.Logarithm

   

   A whitening filter for natural images that flattens the spectrum (on average).

   A whitening filter for natural images that flattens the spectrum (on average).

   This uses the fact that natural images have an amplitude spectrum of 1/f, so this is essentially a filter with the inverse spectrum. The algorithm is from Bruno Olshausen:

   http://redwood.berkeley.edu/bruno/npb261b/lab2/lab2.html