`imrotate(img, pi/2)` changes size of image about imagetransformations.jl HOT 3 CLOSED

The expectation that "imrotate(img, pi/2) should have the same size as img" can be somehow illusive due to the numerical error. A trick we use in this package is to discretization on ratio so that we consistently have imrotate(img, theta) == imrotate(img, theta+2pi) but that doesn't handle special pi/2, pi and 3pi/2 case.

To get the same size you can use imrorate(img, π/2, axes(img)).

Would it make sense to just define a new imrotate specifically for these factors of pi/2?

Yes it totally makes sense, I did some experiment a long time ago in #79 but there are performance concerns.

from imagetransformations.jl.

Would it make sense to just define a new imrotate specifically for these factors of pi/2?

There're Base functions rotl90, rotr90 and rot180 for this very purpose. In the meantime, I still think #79 is needed.

I believe that we also need more documentation on this behavior because other image processing frameworks don't have this axes stuff.

from imagetransformations.jl.

This is also fixed by #148

from imagetransformations.jl.