A system and method that distinguishes between logos and other categories of images, such as natural images, cartoon images, and computer-processed or generated images (“concept images”). The system receives a query image, which may, for example, be intended to be evaluated by an image search and comparison engine to identify matches to a catalog of images. The system evaluates characteristics of the query image, such as the gray-levels in the image, the edge crossings in the image, and the gradient magnitudes in the image, to identify whether the image is a logo. Based on identifying the image is a logo, the logo query image may be excluded from being evaluated by the image search and comparison engine.