JPS5580184A - Character read system - Google Patents

Abstract

PURPOSE: To read only characters of a required color without break and blot by calculating chromaticity coordinates from color separation signals of each point and using a pattern quantized under a fixed condition and a pattern quantized by the threshold of the lightness signal.

CONSTITUTION: Character 61 on recording medium 60 is caused to pass through optical system 62 to obtain color separation signals R, G and B in color scanning unit 63. Chromaticity coordinates r and g are calculated from these signals by chromaticity calculation circuit 64 to obtain patterns P₁ and Q₁ through chromaticity coordinate decision circuits A65 and B66. Meanwhile, G components of signal R, G and B are made into a contrast signal, and pattern P₂ or Q₂ is obtained by circuit 67 or circuit 68 by causing the signal to pass through threshold circuit 67, where the signal is discriminated as a binary with high threshold A, and threshold circuit 68 where the signal is discriminated as a binary with low threshold B. Patterns P₁ and P₂ are caused to pass through AND gate 69 to obtain patern P, and patterns Q₁ and Q₂ are caused to pass through AND gate 70 to obtain pattern Q, and these pattern are caused to pass through joint processing circuit 71 to obtain final binary output R.

COPYRIGHT: (C)1980,JPO&Japio