RETRIEVAL AND MATCHING OF COLOR PATTERNS BASED ON A PREDETERMINED VOCABULARY AND GRAMMAR

The invention provides a perceptually-based system for pattern retrieval and matching, suitable for use in a wide variety of information processing applications. An illustrative embodiment of the system uses a predetermined vocabulary comprising one or more dimensions to extract color and texture information from an information signal, e.g., an image, selected by a user. The system then generates a distance measure characterizing the relationship of the selected image to another image stored in a database, by applying a grammar, comprising a set of predetermined rules, to the color and texture information extracted from the selected image and corresponding color and texture information associated with the stored image. The vocabulary may include dimensions such as overall color, directionality and orientation, regularity and placement, color purity, and pattern complexity and heaviness. The rules in the grammar may include equal pattern, overall appearance, similar pattern, and dominant color and general impression, with each of the rules expressed as a logical combination of values generated for one or more of the dimensions. The distance measure may include separate color and texture metrics characterizing the similarity of the respective color and texture of the two images being compared. The invention is also applicable to other types of information signals, such as sequences of video frames.