JPS5694877A - Binary coding system of video signal - Google Patents

Abstract

PURPOSE:To simplify constitution of a main body device, by comparing the adjacent picture element signals with every N units with the reference level signals of NXM stages in repetition and with every M pieces of adjacent lines and then performing a binary coding of NXM units of picture element signals in correspondence to the gradation of a picture element. CONSTITUTION:The video signal obtained from the pickup CCD line sensor 1 enters the input terminal of the comparator 2 for binary conversion in the form of the time-series picture element signal of each line. On the other hand, the 16 different types of reference level designation signals which are read out of the ROM3 in the form of the 4-bit digital signals are applied successively to the reference input terminal in the circuit 2 after converted into the voltage of the corresponding reference level by the D/A converter 4. In this case, the ROM3 storing the reference level signal is read out synchronizing with the picture element signal and by the output of the 4-bit counter 6 which counts the transfer clocks CLT to the sensor 1 and sent from the control unit 5 and forms the line address plus the output of the 4-bit counter 7 which counts the scanning line clocks CLL and forms the row address.