On Fri, Dec 21, 2012 at 9:08 PM, Ulrich Pegelow <[email protected]> wrote: > Am 21.12.2012 20:36, schrieb Pascal de Bruijn: >> Hi, >> >> We (Tobias and me) just noticed our sharpen module fails at image >> borders. This is particularly noticeable (at 200% zoom) with a radius >> of 8 and amount of 2 and a threshold of 0. In more real-world >> use-cases it's not so noticeable. >> >> Could this be a trivial issue? Or should I create a low priority >> ticket for the long run? >> > > I think it's expected behavior. For the border pixels we can not apply > the normal gaussian convolution filter as it would access pixels outside > the image buffer. For that reason border pixels are just copied from > input image without sharpening. At extreme parameter settings this leads > to visible differences. > > So, if we would want to change that, we would need to make a special > round of convolution taking the above mentioned restrictions into > account, e.g. out of range pixels are replaced by edge values etc. > > I doubt if under real life conditions this really makes a difference and > is worth the effort.
Ok. I would agree with that. So never mind then. > BTW: our OpenCL path does not suffer from this issue as there is a > hardware-enabled option to replace out-of-range pixels by edge values. Ah very nifty. Regards, Pascal de Bruijn ------------------------------------------------------------------------------ LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d _______________________________________________ darktable-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/darktable-devel
