Filter for reducing noise and exalting image digital signals edges according to fuzzy logic.

摘要

Filter achieving noise reduction and digital signal image edge exaltation comprising first and second noise reduction circuit means 2 and 3 designed to elect an image edge. Said first and second noise reduction circuit means 2 and 3 comprise each a first and second comparison element (S1,S2,S3,S4) whose input terminals are designed to receive separate digital signals of an image and an inferential circuit (C1,C2) connected to said comparison elements. Each inferential circuit (C1,C2) comprises a fuzzy logic unit designed to define activation levels (Vi) dependent upon signals generated by the comparison elements. The filter (1) comprises also a noise detection circuit (4) and an image edge detection circuit (6) both connected to the noise reduction circuit means (2,3) and designed to perform operations in accordance with fuzzy logic rules on the basis of activation levels (Vi) defined in the inferential circuits (C1,C2). The filter 1 also includes a noise reduction circuit (5) connected to the noise detection circuit (6) and designed to filter the digital image signals on the basis of the operations performed by the circuit (4). In the filter (1) is also included an image edge exalting circuit (7) connected to the noise reduction circuit (5) and to the image edge detection circuit (4) designed to perform on filtered digital image signals an image edge exaltation on the basis of the operations performed by the image edge detection circuit (6).