Small-Print Tutorial - Getting Ahead in GIMP
Yesterday we took our first, tentative step into the wonderful world of layers. Today we'll learn how to shoop the heads of our favorite politicians onto other people's bodies.
Start by saving and opening in GIMP this picture of the oleaginous former Governor of Massachusetts, Mitt Romney.
In the Layers Window (Ctrl+L), right click on the "Background" layer and select "Add Alpha Channel". This adds a whole new dimension of transparency or alpha information to the layer - like the effect we achieved with the Opacity slider yesterday, but on a pixel-by-pixel basis.
Now the layer has an alpha channel, the eraser tool will punch transparent holes rather than painting over the image with the background color.
Because the background is light and Mitt's outline is well-defined, we can use Fuzzy Select Tool (the "magic wand" Toolbox icon) to select the parts of the picture we want to cut away.
Click the magic wand , then click the off-white background somewhere to the top left of Mitt's head. You should find that a small part of the picture is now surrounded by a "crawling ants" dotted line. We want to make the selected area as large as possible without selecting any of Mitt's head. In the Fuzzy Select Tool options dialog try cranking up the Threshold slider and re-clicking on the background until you're right on the cusp of selecting skin/hair (we got all the way up to 55.6).
Press the <delete> key (menu <edit><clear>) and a big chunk of the background should disappear to be replaced by a grey checkerboard pattern that indicates a transparent part of the picture.
Repeat the process if necessary, clicking on Mitt's clothes and left-over bits of the background until Mitt's head is clear of the wreckage. You can then tidy up. Type Ctrl+A (<Select><All>) to make sure you have the whole layer selected (otherwise you'll be trying to edit just the last fuzzy selection). You can then use the eraser tool to tidy up. It may help to enlarge the picture: <View><Zoom><200%>. You should end up with a disembodied head floating over a grey checkerboard.
It's a good idea to save Mitt for future use. We have to save the image as a GIMP .xcf file as the more familiar .jpg format doesn't understand alpha channels. So, <File><Save As>"Mitt_Romney.xcf".
Now time for the host body. Save and edit in GIMP Hot_Mormon_Boy.jpg.
(Courtesy of MormonBoyz.com - W.T.F.!?)Select the image window for "Hot_Mormon_Boy", Ctrl+L to bring up its layers window and click the new layer icon . Name the layer "Head" and select the Layer Fill Type "Transparency".
Back in the "Mitt_Romney.xcf" image window, Ctrl+A (<Select><All>) and Ctrl+C (<Edit><Copy>). Back again to "Hot_Mormon_Boy.jpg" and Ctrl+V (<Edit><Paste>) to paste a giant Mitt head "floating" over the new transparent "Head" layer.
We need to re-size Mitt. Type Shift+T (<Tools><Transform Tools><Scale>) to bring up the Scale dialog. Make sure the chain linking the Width and Height fields is joined (click it a few times to see the difference) and then change the Width field from the starting 382 to (say) 120. Press tab and you should see that the Height value changes automatically from 611 to 192 (this is because the fields are linked).
We now want to move Mitt's resized head into place: Shift+M (<Tools><Transform Tools><Move>) or click the Move Tool icon in the Toolbox. The cursor will change to a white arrowed-cross. Drag and drop Mitt into place.
Use the rotate tool: Shift+R (<Tools><Transform Tools><Rotate>) to tilt his head enough to cover the boy's ear while being joined at the neck. After a bit of fiddling, Mitt should be in place and you can anchor the floating selection by clicking the anchor icon at the bottom of the layers window. (TIP: GIMP restricts what you can do while a floating selection is active. If your clicks don't seem to be doing anything check in the layers dialog to see whether you're "anchored".)
Use the eraser tool to tidy away any unwanted wattles and you should have an image like the one at the start of this post. Save as an ".xcf" so you can work on the image again and then save as a ".jpg" so you have a publishable image.
Congratulations : you are now an accomplished satirical artist. The Hogarth of our times.
Send copies of any particularly offensive pictures you make to: