Original Description:
This set of icons is a superset of the basic, non-interlaced set from Willem's PngSuite. They are used in Greg's VRML test world (VRML plug-in or external browser required) to test PNG, JPEG and GIF texture conformance in VRML browsers, with mixed but improving results. But insofar as this set extends Willem's suite in a couple of areas, they may also be useful for testing 2D viewers such as web browsers.