Hi Wilhelm, on Tue, 26 Apr 2011 Wilhelm Sanke wrote:
> Hanson presents a series of scripts that are related to each other to > achieve a "blur filter" effect using sort of a 3x3-convolve matrix. I > want to add some information and discuss the issue in a somewhat broader > context. As Hanson did not himself supply a sample stack, I produced one > that contains his scripts along with a number of alternative "blur" > scripts and apart from that added some other filters which might be > interesting for Livecode users that intend to look at image processing. > > You can get the stack here: > <http://www.sanke.org/Software/BlurredVision.zip>. Many Thanks!! :-) > To be able to use the convolve matrix with larger images, I made a > number of changes to Chipp's original script, > abandoning among other things the use of arrays in this context or the > "round" function which speeded up > the performance of the filter by a factor of 10.8, snip > This raises the question why Hanson's scripts are so much slower - 12 > times - than "matrix blur 3x3"? I did not yet find time for a detailed > analysis, but I believe that - even given the special structue of the > related scripts - the performance could certainly be improved. One > recommendation would be *not* to use arrays , which against popular > belief really "slows down" performance in this context of image processing. Oh well, this explain why a bezier function that uses arrays (in an older version of my "Import Vector graphics" stack ) was slower than other two arrayless functions. Ideally, your post, Wilhelm, should be archived in a more visible place, like the Livecode Lessons or as a "Sticky" message in the Forum. Al _______________________________________________ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode