JPS56168284A - Mark reading system - Google Patents

Abstract

PURPOSE:To reduce reject processing by sending the information of black picture elements from a timing mark detecting circuit to an information processor when there are the black picture elements between an upper thershold value and a lower threshold value and executing decision. CONSTITUTION:A scanning position assignment mark detecting circuit 11 examines the presence or absence of any place where more than a constant number of black picture elements continue within the constant position from the left end of the respective scanning lines that it receives, and produces an output as the scanning line where the scanning assignment position mark exists only when said place exists. A timing mark detecting circuit 12 detects the position of the black picture elements existing on the scanning line that it receives and instructs this position to a counter circuit 13. This circuit 13 successively receives such scanning lines, counts the black picture elements of the specific positions on the scanning lines assigned by the circuit 12, and outputs the same to a mark decision circuit 14. On receiving these, the circuit 14 makes decision of the presence of the mark when the number of the black picture elements is above the upper threshold value, makes the decision of the absence of any mark when it is below the lower threshold value, and decides the value between both thresholds as an ambiguous mark, thence the decision is made in the information processor.