Common use of 1H delay circuits (14 and 15), which are used as parts of a contour correction circuit (17) and a comb filter for reducing the interference between the luminance signal and the color signal (cross color noises), reduces the required number of the 1H delay circuits, and the space for mounting...http://www.google.com/patents/US5019895?utm_source=gb-gplus-sharePatent US5019895 - Cross color noise reduction and contour correction apparatus in NTSC color television image processing system
