[SciPy-User] Image analysis: Counting masked areas

[Michael Aye]

Dear all,
is it possible to count the areas in an image, that have been masked
by some condition?
I need to count all areas in an image darker than a certain value.
Masking is no problem, but how do I count independent areas? I was
thinking just to look at the masked array, but then a pixel-by-pixel
check if the neighbour pixel is masked as well to find *independent*
masked areas sees numerically very costly.
Isn't there a better way?

Many thanks for any help!

Best regards,
Michael