CIRCUIT FOR CONVERTING ANALOG PICTURE SIGNAL INTO BINARY SIGNAL

PURPOSE:To facilitate the circuit integration of a circuit and the processing of a binarized signal by converting an analog picture signal level into a digital code signal, forming sequentially a signal representing a mean level of the binary coding signal and using the mean level so as to convert the digital code signal into the binarized signal. CONSTITUTION:An analog picture signal A(v) is outputted as a digital code signal D(v) by an A/D converter 3. An edge detection circuit 4 outputs a signal P1 when a signal D(v) at the preceding clock is larger than a signal D(v) formed by the clock at present time to rewrite the signal D(v) inputted in a memory 5 and rewrites the signal D(v) inputted in a memory 6 when the signal D(v) at present time is smaller than the signal D(v) at the preceding clock. An arithmetic circuit 7 outputs a mean value of digital code signals D(v) stored in the memories 5, 6 at the reflected change point of the signals P1, P2. A binary coding signal C(D) corresponding to a white/black level is obtained at a digital comparator 8.