Hi all,

I'm currently trying to use a median filter on my data, an am getting an error that I can't seem to debug.

I'm taking the difference of two images (both numpy.float64), scaling them between -1 and 1, and trying to apply a median filter. My image satisfies the conditions for being between -1 and 1 when I do the following test:

print diff.min()/dmax < -1.0 -> returns False (LHS evals to -1.0)

print diff.max()/dmax > 1.0 -> returns False (LHS evals to 0.663919388648)

The statement causing the error:

filtered = fltr.median(diff/dmax, selem)

where diff is my difference, and dmax is my scaling adjustment, selem is a disk of radius 2

This gives me the following traceback.

Traceback (most recent call last):

File "/home/clustering.py", line 138, in image_ratio

filtered = fltr.median(diff/dmax/2.+0.5, selem, mask=m.astype(np.bool))

File "/usr/local/lib/python2.7/dist-packages/skimage/filter/rank/generic.py", line 369, in median

out=out, mask=mask, shift_x=shift_x, shift_y=shift_y)

File "/usr/local/lib/python2.7/dist-packages/skimage/filter/rank/generic.py", line 71, in _apply

out_dtype)

File "/usr/local/lib/python2.7/dist-packages/skimage/filter/rank/generic.py", line 34, in _handle_input

image = img_as_ubyte(image)

File "/usr/local/lib/python2.7/dist-packages/skimage/util/dtype.py", line 358, in img_as_ubyte

return convert(image, np.uint8, force_copy)

File "/usr/local/lib/python2.7/dist-packages/skimage/util/dtype.py", line 191, in convert

raise ValueError("Images of type float must be between -1 and 1.")

ValueError: Images of type float must be between -1 and 1.

Has anyone else experienced this problem before? I tried searching in the groups, but couldn't find anything relevant.

Any help would be greatly appreciated!

Thanks,

Aman