Robert Hanson :

If you have been watching the news groups you will have heard about the upcoming GWT 1.4 release, and the long list of features it will include. One of these features is the ClippedImage class. This article is meant to explain how to use ClippedImage, and the details of how it can optimize image loading in your GWT application.

GWT ClippedImage - Optimizing Image Loading
Source gwtsite.com