Method for enhancing detail in color signals and circuitry for implementing that method in color video equipment

摘要

In video signal processing circuitry detail enhancement is done on each of three color channels in response to the detail information, the enhancement of the detail in each color channel being done in reliance on separated high-spatial-frequency information originally contained in that channel, as long as it is sufficiently greater in amplitude than a reference level somewhat above that expected for thermal noise. When the amplitude of the detail information originally contained in a channel is insufficiently above that reference level, the thermal noise is suppressed by subtracting the separated high- spatial-frequency information therefrom. The same filter arrangements are used to separate high-spatial-frequency information for suppressing thermal noise in each color channel as for enhancing the detail in each color channel.