Do you remember Picture Pages? You know,
Picture pages, picture pages. Time to get your picture pages. Time to get your crayons and your pencils... Sometimes my family accuses me of making up memories and my memories of Picture Pages is so vague that I thought perhaps I had made it up. But thanks to Google and YouTube, I was able to assure myself that I hadn't made up this classy little ditty.
I read a tutorial a while back about how to turn photos into coloring pages. Basically, you use Photoshop or something similar and use the "photocopy" tool to turn a color photo into a black and white line drawing. But I didn't really like the results so I've been trying different methods. I've finally found a method that works pretty well, so I thought I would pass it along.
First of all, you'll need some kind of photo manipulation software. I use
GIMP because it's free. If you've never used software like it, it can be a little intimidating. At least it was for me. When you open GIMP, there are several windows. This is what mine looks like when I have a file open:

Of course, when you start Gimp, you probably won't have a file open. To open the photo file, go to File > Open. Viola! Now you should have a photo and the two other windows open. If for some reason the Layers window isn't open, you can open it from File > Dialogs > Layers in the Gimp window. But you don't really need the Layers window for this exercise, so it doesn't matter.
I'm going to use this photo of my family posing at the Riesenrad at the Prater.

When I convert the photo using the Photocopy filter (Filters > Artistic > Photocopy), this is the result.

It's not completely awful, but it's not a good coloring page. So instead of using the Photocopy filter, I tried the Edge-Detect filter (Filters > Edge-Detect > Difference of Gaussians). And here's the result.

I like this one much better, but the lines are too light. So after using the Edge-Detect filter, I tried some of the features under the Colors menu to see if I could make the lines darker. Now a word of warning. I don't really know what I'm doing. I understand how some of the features work, but mainly I just play around.
The first thing I do is make the photo black and white. Even though it looks black and white after you add the Edge-Detect filter, there may be a little color still in the photo. So select Colors > Desaturate and then click "Desaturate" on the popup menu. Now you can play with some of the other options in the Colors menu and see what you like best. This is what I came up with.
Colors > Colorize. I increased the Hue and Saturation. Since this changes the color, once again I made the photo black and white by using Colors > Desaturate.

Colors > Threshold. I slid the bar to the right until the lines were darker, but the entire photo wasn't dark.

Colors > Levels. I moved the bar on both the Input Levels and Output Levels towards the right. I honestly have no idea how you're supposed to use Levels, so I just played with it until I found the levels I liked.

Colors > Curves. I use this feature a lot to lighten dark photos, but today I used it to make the lines darker. Just grab the line and pull it downwards.

I haven't decided which style I like best. What do you think?