Rainbow Effect on Photo(GIMP Tutorial)

As 4^th year Computer Science student, one requirements in order to pass and to graduate this course is the subject ITC 100 which the fourth year students should organized their own seminar but this time our seminar is cancelled and we changed it to workshop. Last Saturday January 10, 2009 we started the workshop and it is only intended for 2 Saturdays only, so our last workshop is on January 17, 2009, during that time, we, the organizers are in charge on giving tutorials to the selected students of our school. The fourth year students decided that our topic will be GIMP or the GNU Image Manipulation Program which is free software that you can download online. It just like the Photoshop because in GIMP, you can also edit your pictures and make such graphics or wallpaper. One of the topic which we discuss in our workshop is the Rainbow Effect on Photo. I like this tutorial very much. So if you want to know about this tutorial, I have here the list of steps which you are going to followed.

 1. Open GIMP. Go File>New and make it whatever size you want. I used 500 x 660 canvas size.

 2. Next go File>Open as Layer and choose your base. I used this:

 3. Select your top layer/base and go Layer>Color>Desaturate.

4. Go Filters>Artistic>Photocopy and fiddle with your settings until it looks something like this:

5. Use the ‘Select regions by color’ tool. Click on a patch of black somewhere, it doesn’t matter where.

 
6. Delete your base layer. Now you should have only your original background with the dotted ‘marching ants’ outline of your pic.

 
7. Create a new transparent layer.

 
8. Set your Foreground and background colors. Just choose the color you want, but in this tutorial I used red for the foreground and blue for the background. Select the Gradient tool. Keep it set to Normal at 100% opacity. Use FG to BG.

 
9. Now click and drag making a line over your picture. Just click on the picture whether it is horzontal or vertical depending on you.

 
10. Now go Select>None
  

11. Flatten your image and you’re done.

          I hope that you will enjoy this simple tutorial. And by the way, here’s the sample output of the Rainbow Effect on Photo that I’ve made in GIMP.

 Output: