JoeChip, Great post on the conversion of wave maps to terrains. A couple of other suggestions along this line:

Caustics Generator creates 8-bit BMP files, so you can convert them to 16-bit files (better resolution) by opening them in Photoshop and using the following technique (which works for converting any 8-bit images to 16-bit images)

This technique should also work pretty well to remove artifacting created by JPG files. It's not a good idea to use JPG files for terrain creation as even the smallest amount of artifacting can be problematic.

1. Convert the Mode (Under Image menu) to Grayscale and 16 bits/channel.

2. Resize the image 400%: Image menu->Image Size Make sure you check "Resample Image: Bicubic"

3. Gaussian Blur the image with a value of 20 (larger or smaller depending on image size)
   Resize the image back to original size: 25%

You should now be good to go with your new terrain map. You may wish to consider adding a bit of noise after step 2 as well, or an unsharp mask after step 3. Salt and pepper to taste.

HTH,

Chipp