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Misc. Filters

Magic Eye

Magic Eye is a way to create 3D stereo images in Gimp. I think everybody have seen 3D images in magazines. A strange-looking image that you have to look at in a certain way, and up pops a flower or something. Now you can do the same thing in Gimp. Here is how it works:

Example and parameters

• First create a grayscale map image, (the image containing the 3D thing that will popup)
  
• Create a mask image (this is the image which will hide the map image). The image must have several colors in it (a repeated texture is great), if this is going to work properly.
  

• Bring up the filter from the map image.
• Select the mask image in the Background menu
• In the Strip slide bar, set how many columns (a column is one pixel wide) of the mask image you want to use for the background pattern clone strip (preferably between 50 and 100). The columns are counted from the left.
• Remember that you must leave the first and last part of the map image black (about half the size of the background strip).
• Depth is the amount of 3D you want (or how much you want the thing to popup).
• From left will build your image from the left instead of from the middle of the image. (I have noticed that a 3D image is often easier to see if you create it from the left.)
• Down carves the image instead of raising it.
• You have now hopefully chosen Depth, Mask and Strip.
• Press OK or Create, and the new 3D image will appear
  

Remember that the brighter the object is in the map image, the higher it will pop up in the stereo image.

Stereogram

Creates a 3D stereogram of a grayscale image (similar to Magic Eye). It works like this:

How to:

• Create a simple grayscale image (the popup).
• Bring up the plug-in
• Choose a background (an RGB image of equal size)
• Choose stereogram type: SIS or SIRDS
• press OK

Now you have a stereogram. Take a good look at it with the focus slightly behind the image, until the 3D representation of your image appears in the stereo image.

Parameters

If you check SIS (Single Image Stereogram), the background will be used as a pattern. In SIRDS (Single Image Random Dot Stereogram), you'll only get a stereo noise for background.

Video

This plug-in creates the illusion that the image is an ordinary low-res/dot pitch video monitor. You can achieve this with different patterns, which means that you can create a whole lot of "bad monitors". By default the pattern is horizontal, but you can by checking Rotated let it be vertical instead. Use Additive to get a realistic look. For an explanation of Additive, see the Modes chapter. If you don't use Additive, the pattern will just get on top of the image and darken it a lot.