Johannes Buchner

Hi @MansMeg, please send me an email.

Huh. Do you know why db4 does that?

The two wavelet shapes: http://wavelets.pybytes.com/wavelet/db4/ http://wavelets.pybytes.com/wavelet/haar/ (nothing obvious there) [The whash function](https://github.com/JohannesBuchner/imagehash/blob/master/imagehash/__init__.py#L344) calls this: https://pywavelets.readthedocs.io/en/latest/ref/2d-dwt-and-idwt.html#d-multilevel-decomposition-using-wavedec2 with default mode ('symmetric') Maybe have a look at the input and output of this...

In any case, given how differently the various methods work, no, `hash_size` does not necessarily have to have a consistent meaning across all methods.

On Ubuntu Linux, I got the same error as @MichelDC, with up-to-date cython and cython upgraded using pip: ``` ± pip3 install pypmc Collecting pypmc Using cached pypmc-1.1.4.tar.gz (1.0 MB)...

pinging @joshcoales who contributed this code and perhaps has an opinion.

Perhaps you could prepare a PR (plus test of commutativity, perhaps for all hash types), and add comments with some demonstrations of the behaviour before and after.