Picture signal processing method

Abstract

Abstract PURPOSE:To obtain a picture signal processor which can discriminate a character image and a halftone image with high reliability by discriminating an image from a mutual relation of a density average of an image block consisting of plural picture elements, and the maximum value of a density difference between these picture elements. CONSTITUTION:An analog picture signal 22 of an original which has been brought to an image pickup by an image sensor 21 is supplied to series circuit of line memories 26, 27 and a series circuit of latches 251-253 through an A/D converter 23. Outputs of the line memories 26, 27 are supplied to series circuits of latches 254, 250 and 255, and latches 256, and 277 and 258. Outputs of each latch 250-258 are provided to an average value circuit 31, an average value is derived, and also a density difference between the latch 250(notice picture element) and the latches 251-258 (its peripheral picture elements) is derived by subtracting circuits 241-348. Said density difference is applied to a maximum value circuit 35, the maximum value of the density difference is derived, and from a mutual relation of the maximum value of this density difference, and said average value, the kind of an image is discriminated by a discriminating circuit 23.

Inventors

• 👤 Taiji Nagaoka
• 👤 永岡　大治
• 👤 Hiroyuki Saito
• 👤 宏之 斎藤
• 👤 Fuminari Matsumoto
• 👤 松本　文成
• 👤 Masami Kurata
• 👤 倉田　正實

Bibliographic Details