Color correction system and method with scene-change detection

Abstract

A color correction system with an improved scene-change detection module is disclosed. The scene-change detection module processes video picture signals representative of images stored by an image recording medium to detect the start of a new scene. The module advantageously includes circuits which sense a change in each of at least two different parameters of the video picture signals. The changes are analyzed in relation to a preselected condition. The module also includes circuits which generate a change detect signal when the change in at least one of the two parameters satisfies the preselected condition. Preferably, an area discrimination circuit is employed to limit the portion of the video picture in which the signals are sampled for scene-change detection purposes. One of the parameters that may be analyzed is a signal indicative of the color content of the video picture. Another parameter that may be analyzed corresponds to signals in a particular frequency range, which frequency range is below the range of frequencies for chrominance signals. As an alternative, the scene-change detection module may analyze just signals in a preselected frequency range when trying to find the start of a new scene. Each parameter may be analyzed by determining its average level in at least a portion of one video field, determining its average level in at least a portion of another video field, and then comparing the difference in average levels with a predetermined standard.