Pull request: morphology fix

[Stéfan van der Walt]

Hi Tony

On Sat, Oct 15, 2011 at 1:58 AM, Tony Yu <tsyu80 at gmail.com> wrote:>
The open/close operations aren't that bad: they just shift features.
But,
> when calling white/black tophat operations, the shifting can lead to
> over/underflow of pixels. I've attached examples of the lena image after
> calling white tophat, both before and after the fix. The underflow should be
> apparent in the first image.

Thanks for investigating and fixing this subtle bug.  Talking about
data-types, we should gradually move towards using the data type
helper utilities, and thereby avoid possible over and underflow
issues.

Regards
Stéfan