According to John C. Russ in his classic text The Image Processing Handbook, image processing is usually done for two purposes:
1. "improving the visual appearance of images to a human viewer, and
2. "preparing images for measurement of the features and structures present.
Image enhancement is especially important in criminalistics in order to facilitate the identification of an individual in a blurry photograph or video capture, but is also important in civil forensic to identify the exact location or dimensions of objects in photographs of an accident or fire scene. Enhanced digital images are also used to produce compelling visual evidence such as boundary locations in a land rights dispute. For 25 years, Ebert and Associates has used digital enhancement techniques in evaluating legal evidence.