Character area extracting circuit

Abstract

Abstract PURPOSE:To extract a character area through a simple circuit by detecting the density gradient of an image, extracting a contour which limits the range of the character area on the basis of the projection value, and deciding on the character area according to the projection value of the limited range. CONSTITUTION:A picture from an input part 1 is converted into a 512X512 digital picture A differential arithmetic circuit ( I )2 detects the longitudinal edge through a differential filter and a differential arithmetic circuit (II)3 detects the lateral edge through a differential filter to obtain differential density values of the picture. Those outputs are inputted to projection circuits (longitudinal) 4 and (lateral) 5 respectively to project the number of picture elements having density values above a threshold value. Projection values of the projection circuits 4 and 5 are inputted to contour extracting circuit (longitudinal) 6 and (lateral) 7 to decide the contours. Both contours are inputted to projection circuits (longitudinal) 8 and (lateral) 9 together with the outputs of the differential arithmetic circuits, thereby detecting the longitudinal and lateral projections of a character part. Those projection values are inputted to character area line extracting circuits (longitudinal) 10 and (lateral) 11 to decide character area lines.

Inventors

• 👤 Noboru Ozaki
• 👤 暢 尾崎
• 👤 Takashi Torio
• 👤 隆 鳥生
• 👤 Toshiyuki Goto
• 👤 敏行 後藤
• 👤 Hiromichi Iwase
• 👤 岩瀬　洋道

Bibliographic Details