- Tong - on wrote... | On Tue, 24 Jul 2007 12:44:50 +1000, Anthony Thyssen wrote: | | > Try using ... | | Thanks Anthony for your reply. I re-formulate the OP into the following n= | ew | question: | | How to correctly produce the sketch effect with pictures that have | transparent backgrounds, I.e., those pictures whose backgrounds have been | cleared using gimp? | | This is what I need to do[1]: | | . Duplicate the picture into 2 layers. | . Gaussian Blur the top layer with a radius of 7 pixels. | . Invert it (the top layer), and set its opacity to 50%. | . Merge the two layers. | | The last two steps will effectively subtract the top layer from the | origi= nal layer to obtain a high pass filtered version of the | original picture. | | This is what I've tried: | [1] http://www.gimp.org/tutorials/Sketch_Effect/ | | | convert pic1.png \( +clone -median 2 -blur 0x7 -negate \) \ | -matte -channel A -evaluate set 50% -compose plus -composite pic11.g= | | if and | | convert pic1.png \( +clone -median 2 -blur 0x7 -negate \) \ | -matte -channel A -evaluate divide 2 -compose plus -composite pic12.= | gif | | First of all, please take a close look for me if the commands are in fact | that what I planned to do. Now here are the problems: | | For the 1st command, the cleared background shows up again in the result.
Of course it does, you set the whole matte channel to 50% trasparency. I would suggest you avoid using GIF, use MIFF or PNG, for working images it is probably adding to the confusion as GIF can not save semi-transparency. Also using 'display' to display results shows you what parts are semi-transparent. | As an attempt to fix it, I tried the 2nd one, but this time the cleared | background shows up in bright colors, as opposed to the rest of images | which have the dull high pass filtered effect. | | Please get the original picture from | http://xpt.sourceforge.net/download/pic1.png | and test for yourself, and see if you can find a way to make it work. | I displayed the second image results in 'display' and it shows correct working. No bright colors. What version of IM are you using? Anthony Thyssen ( System Programmer ) <[EMAIL PROTECTED]> ----------------------------------------------------------------------------- Ok, pop quiz. There's a server on a bus. It's rigged to blow if it drops below 50 transaction per second. What do you do? --- WWW-Speed Home Page -- Simon Spero ([EMAIL PROTECTED]) ----------------------------------------------------------------------------- Anthony's Home is his Castle http://www.cit.gu.edu.au/~anthony/ _______________________________________________ Magick-users mailing list [email protected] http://studio.imagemagick.org/mailman/listinfo/magick-users
