Legacy ImageMagick Discussions Archive

Hi, I'm looking for an ImageMagick expert to help me translate this halftone offset script that is listed in the docs to iOS: convert parrots_med.png -set option:distort:viewport '%wx%h+0+0' \ -colorspace CMYK -separate null: \ \( -size 2x2 xc: \( +clone -negate \) \ +append \( +clone -negate \) -ap...

Anthony - has anyone translated the halftone offset script to one of the coding APIs before?

Well I found an example on Stackoverflow where a guy lists his command like this: char *input_image = strdup([[[NSBundle mainBundle] pathForResource:@"iphone" ofType:@"png"] UTF8String]); char *output_image = strdup([[[NSBundle mainBundle] pathForResource:@"iphone" ofTy...

Actually updated some of my code, I was failing to get the resulting image from the blob. Now if I substitute ConvertImageCommand with MagickBooleanType status = MagickPosterizeImage(wand,6,MagickFalse); that actually works. However, still having trouble getting ConvertImageCommand to work. A guy on...

At the command-line, "-ordered-dither" is a single token, with no spaces. I don't know if this is your problem. Thanks for taking a look. I've actually tried it the way you mentioned and when I do the status comes back as false. When I split them as above, the exception gets thrown, so no...

Done a little searching around and so far able to come up with: MagickWandGenesis(); MagickWand *wand = NewMagickWand(); NSData *data = UIImagePNGRepresentation(self.originalImage); MagickReadImageBlob(wand, [data bytes], [data length]); int arg_count = 3; char *args[] = { "-ordered", &quo...

the second example in the IM Examples link shows how you can scale it. However using the builtin "pattern:gray50" pixel level checkerboard image may work better. You can then just scale it during the rotation distortion, to whatever size you like. That is to get the screen part (usually a...

Hi, I've just added the iOS ImageMagick by Claudio to my project and was wondering if there are any examples for using MagickWand in iOS? I'm just trying to do simple stuff like: convert pug.png -ordered-dither h4X4a pug2.png and am not really too versed in C. Is it possible to take a UIImage and ad...

You are probably using Unix syntax on Windows. See http://www.imagemagick.org/Usage/windows/ for how to convert the syntax. Thanks, that helped me get it and it looks great! I was wondering, is it possible to specify a size for the halftone squares? When I apply the filter to smaller images the squ...

The comic book effect is essentially a halftone screen. A true half tone screen. However try the method in the link I gave, it will probably achieve what you want. With or without 'posterize' http://www.imagemagick.org/Usage/quantize/#halftone_offset Had another question (a noob question). I am try...

fmw42 wrote:Your output seems to have some kind of posterize effect. The black squares may come from the darker colors being assigned to black in the posterize process or just a final -black-threshold.

Yeah I've actually tried posterize and it looks better than what I linked to. Thanks!

Thank you guys will try both things.

You say the Imagemagick half toning lighten the image. To me the method you provided (second example) darkened the image! There are lots of ways to get effects like what you exampled, though your example looks more like offset hafltone screening, with a very bad or 'slightly randomized' halftone pa...

Thanks! Going to try that out.

Hey all, I have the following image: http://i58.tinypic.com/2anczm.jpg Which has a halftone effect and maybe some other effect applied to it: http://i60.tinypic.com/2mwib29.jpg I am wondering, is it possible to replicate this effect in ImageMagick? I've played around a little with the halftone dithe...