HornetsEye is a Ruby real-time computer vision extension. It offers interfaces to do image- and video-I/O with ImageMagick/Magick++, Xine, firewire digital camera (DC1394), and video for linux (V4L).

For more information about HornetsEye have a look at the project homepage:
http://rubyforge.org/projects/hornetseye/

The new version has image warping which can be used to implement a Lucas-Kanade tracker (see examples). There is also pixel-wise mapping which can be used for fast morphological operations.

You can download the most recent release of HornetsEye at:
http://rubyforge.org/frs/?group_id=2714