CONTOUR LINE EXTRACTING DEVICE

摘要

PURPOSE:To realize a device which is tolerant to noises and has isotropy and simple constitution, by outputting a signal for indicating the presence of a contour line when an input picture signal has a value between two threshold values. CONSTITUTION:Two computers 31 and 32 constitute a comparing circuit 33. Voltages VA and VB (VA>VB) are applied as threshold voltages to one-side input terminals of the compararors 31 and 32 and the input picture signal VI is supplied to the other-side input terminals. The output of the comparator 31 and the output of an inverter 35 which inverts the output of the comparator 32 are ANDed by an AND circuit 34. Its AND output is the output of the contour line extracting device.