Patent ID: 6169583
Filing Date: 2001-01-02
Classification: H04N

Abstract:
A method of determining a noise value that corresponds to a noise in a video signal, the video signal comprising fields or frames in periodic intervals, said method comprising: inputting the video signal into a noise measurement apparatus, wherein the noise-free video signal comprising identical signal portions at predetermined periodic intervals, preferably per field or frame; separating two subsequent portions of the video signal, wherein the subsequent portions correspond to the identical signal portions of the video signal; calculating an absolute difference value between two corresponding signal values of the two separated portions of the noise-free video signal; limiting an extreme peak value of the calculated absolute difference value to a predetermined maximum value by limiting an absolute difference value which exceeds a predetermined value; regarding the calculated noise value for one field or frame as being invalid if more than 25% of the calculated absolute differences for one field or frame exceeding a predetermined value accumulating a predetermined number of calculated absolute difference values; and outputting an accumulated sum representing the noise value from the noise measurement apparatus.