NOISE REDUCTION SYSTEM FOR COLOR TELEVISION SIGNAL

摘要

A noise reduction system for improving the S/N ratio of a color television video signal is described. A frame portion of the video signal is stored in a memory and a fraction of this frame portion is added to a fraction of an immediately following second frame portion. The signal level difference between the first and second frames determines the fractions to be added. The outcome is that with higher level signals less noise reduction is attempted than with lower level signals. The system also has a frequency dependent equalizer for attenuating the high frequency components of a difference signal representing the difference between two frame portion signals. The effect of this is to affect the high frequency components more than lower frequencies and this is beneficial because noise tends to be high frequency.