Abstract: If a scene change is not detected by a scene change detector, in each frame until a count value of a frame counter reaches a predetermined value, a tone curve pattern updater sets a representative point group of a tone curve pattern selected in the most recent frame in which a count value is reset to an initial value as a representative point group for updating. By assuming that k is a number less than 1, the tone curve pattern updater generates a first multiplication value obtained by multiplying the set representative point group for updating by a coefficient (1?k) and a second multiplication value obtained by multiplying the representative point group output by the tone curve pattern updater in an immediately preceding frame of each frame by a coefficient k, and outputs a combined representative point group obtained by adding the first multiplication value and the second multiplication value.

Abstract: If a scene change is not detected by a scene change detector, in each frame until a count value of a frame counter reaches a predetermined value, a tone curve pattern updater sets a representative point group of a tone curve pattern selected in the most recent frame in which a count value is reset to an initial value as a representative point group for updating. By assuming that k is a number less than 1, the tone curve pattern updater generates a first multiplication value obtained by multiplying the set representative point group for updating by a coefficient (1?k) and a second multiplication value obtained by multiplying the representative point group output by the tone curve pattern updater in an immediately preceding frame of each frame by a coefficient k, and outputs a combined representative point group obtained by adding the first multiplication value and the second multiplication value.

Abstract: A quasi-composite video signal generator incorporated in a microcomputer having a circuit for generating a quasi-composite video signal to be used to adjust a cathode ray tube (CRT) of a display unit, and the microcomputer being incorporated in the display unit. This generation circuit has a synchronous signal generation section for generating horizontal and vertical synchronous signals, a display setting unit for setting an image to be displayed, and a signal generator for generating a three-state signal Vout according to the image set by the display setting unit and the horizontal and vertical synchronous signals. The signal Vout is converted by a shaping circuit into the quasi-composite video signal, which is applied to drivers of cathode electrodes of the CRT.