US Patent 7405747 Extended K2T measurement of video

K2T measurement of video signals, regardless of video format, is determined by generating a graticule using an algorithm having a single variable that is a function of the video format for the particular video signal. The graticule is set to a normalized value of one for a range of +/−T, where T is a function of the video format. The graticule is set to a normalized value over a range of +/−(1.5T to flatBreak) according to a human vision masking model algorithm expressed as K+C/t, where K is a constant K factor, t is a function of T, and C is the single variable that is a function of the video format. The normalized value of the graticule beyond a point designated by flatBreak is a constant=K. Finally a linear curve fit between one and K+C/t over the range of +/−(T to 1.5T) sets the remaining values for the graticule.