Bump Mapping is an effective way to add surface-dimension to still images and textures by allowing light to interact with the contours of the surface. Usually this is done in a 3D program but a similar technique can be imitated in After Effects, as shown in the latest Short_Cuts Tutorial.
The above example shows how bump mapping can have a dramatic effect on a still image, but sometimes a separate bump map is needed to simulate the proper depth. I created a new bump map by manipulating the original image to look like the one on the right. The white area designates “extrusion” while the black stays unchanged.
This new image is then selected by the Glass filter to be used as the “Bump Map” layer. After playing with the settings, the bricks now appears to extrude slightly. The actual settings can be seen by clicking on the screen shot.
QUICK TIP: The bump map doesn’t have to be a descendant of the original image. Think of the possibilities…
Also be sure to play with the material options to mimic the properties of the surface. In this case, dull bricks don’t have as much specular hot spots.
Now if you have already built bump maps to use in your 3D program, then you know how fun it is to make custom bump maps from images. Unfortunately, simply inverting an image is never good enough because the necessary depth information is not always black or white.