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Software to Divide an Image Into Discrete Patterns
slashyslashy asks: "My preschooler son is fond of color-by-number pages. We have already exhausted most of the online sites that offer somewhat limited sets of coloring pages that he can print to a paper and color. Besides, most of them offer extremely basic (read boring) sets of simple images (flowers, dinosaurs, etc). We were wondering if we can take any regular picture image and convert it into a pattern suitable (divide up the black and white picture into series of random patterns) for color-by-number pages. Is there any good software that allows converting a picture to a pattern suitable for coloring by numbers? Linux is preferable but Windows is also fine. Thank you."
It's discrete, not discreet.
The World Wide Web is dying. Soon, we shall have only the Internet.
Open inkscape. Drag image in. Select imported image. Go Path -> Trace bitmap. You'll probably want to use the 'multiple scanning' options. Probably with fewer than the default 8 scans. Select created vectors. Open the fill & stroke dialog and set it to 'no fill' and a plain black stroke.
As always, you'll want to play with parameters to get good results.
Malike Bamiyi wanted my assistance.
Search Google for "color by numbers software" http://www.stoik.com/hobby/Color_By_Number/ Is it really that hard?
http://imagemagick.org/ is free, runs on most any platform you'd ever case to use, and implements fuzzy c-means for image segmentation (which basically turns regular photos into "coloring book" versions of themselves). the c-means segmentation may be a bit too coarse for what you want to do. in that case, implementing a mean-shift segmenter (google for comaniciu and meer) will probably do a nice job. hope this helps!
First, The Gimp makes something like this pretty easy. Open an image and go to 'Image -> Mode -> Indexed...', select the Generate Optimized Palette, and select the number of colors you want to use (10 might last your son 5 minutes, 200 might last him four years). Turn dithering off and hit OK. Next, go to 'Image -> Mode -> RGB' to switch it back to RGB color, then go to 'Filters -> Artistic -> Cartoon...', tweak the settings (Mask radius=10 and Percent black=1.0 seem to work), and hit OK. With these two, I was able to get a 'completed-looking' color-by-numbers image from a photo in about 10 seconds. The rest is up to you (I would start by selecting by color, getting the black outlines, and copying them into a new layer. Add in numbers and a legend, and you're good to go). If you want to get fancy, you could use some python-jitsu and whip up some script-fu to do it automagically.
Second, you can keep it hardcore and use a program like NIH Image (or its PC counterpart, ScionImage) and use a procedeure called thresholding to get different levels of black and white from an image. The program is scriptable, and if you google around enough (or poke through the sample scripts) you might be able to hack something together pretty easily. I've used this software to track points glued onto soft tissues (ligaments), and if I recall correctly, it was fairly easy to get it to do this sort of thing (i.e., Biomedical Engineering undergrads were able to get it to work). N.B. This is a serious research-level program, so it is not super user-friendly. I also doubt you'll find anything in the help forums if you search for color-by-number. Search instead for thresholding.
The first option is likely to be waaay easier than the second.
It's called Photoshop.
1. image->adjustments->posterize
2. filter->stylize->find edges
3. image->adjustments->desaturate
4. image->adjustments->levels, pull the leftmost triangle all the way to the right
You can skip the first step, but then it'll be reeeeally complex.
You might also want to scale your images up a lot before processing them.
Or you could use autotrace tools like Streamline, or the "LiveTrace" feature built into Illustrator.
Or you could pop up another layer over it and trace the image by hand, then turn off the original image layer and print it out.
Or, yeah, you could just go buy some coloring books, they're reeeeeeally cheap!
egypt urnash minimal art.
>It's easy to write but no one has done it.
It's actually, both mathematically and computationally, a very difficult problem.
Image Segmentation
I'm sure if you know how to do it, and write a nice paper, those folks will be very interested though..
A tip: most things that are obvious problems that 'no one has done' are actually quite difficult if you think about them for more then 10 seconds.
my password really is 'stinkypants'
I would bet that ImageJ would do the job for you.
It is multi-platform, fairly fast and has a number of plugins and macros. If you find a combination of operations that work well, you can save it as a macro that a kid could probably handle on their own.
It is available at http://rsb.info.nih.gov/ij/index.html.
The website is rudimentary, but the program itself is fun to mess with.
Warning: The intelligence of this post may be larger than it appears.
You'll find that there are quite a few programs and websites out there that will breakdown an image into areas of certain colors. They work really nicely. You'd just need to convert the cross stitch thread numbers to colors for your pre-schooler.