MISC: Various minor comment fixes

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
ALGORITHMS: Fix KissFFT wrapper, now using the fully complex DFT

The wrapper of the real value was not consistent with what was
in use previously (e.g. DFTRaw).
In order to ease things and make it works, we now use the
fully complex and probably suboptimal version.
Fixes #19.
See #23 for future real DFT algorithm use.

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
ALGORITHMS: Updated DftRaw tests to be consistent with those of KissFFT

This includes out data length and DFT length being less intricated.

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
ALGORITHMS: Add basic sanity checks for both DFT algorithms

THis proves very useful when developing/optimizing these algorithms.

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
ALGORITHMS: Spectrogram now rely on KissFFT algorithm

Fixes #19.

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
DESCRIPTORS: Move log2() function into a common file

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
SCRIPTS: Minor test added for development purpose, similar to the C++

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
DESCRIPTORS: Update ASC range test so they are actually useful

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
ALGORITHMS: Make Apodizer class more generic

These are only minor naming/comment changes in order to make this class
easily reusable.

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
ALGORITHMS: Add a scale generator class

This will be more efficient than recomputing the scale at each iteration.

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
DESCRIPTORS: Move low/high edges computation out of the inner loop

These only have to be done once, hence we moved it in the constructor.

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
DESCRIPTORS: In ASC, now using the frequency scale generator

Signed-off-by: Gama <misept.dieseneuf@gmail.com>