NOISE ELIMINATION DEVICE FOR VIDEO SIGNAL

PURPOSE: To provide S/N improving effects better than before without generating picture quality degradation in the noise elimination device of a cyclic frame using orthogonal transformation. CONSTITUTION: In this noise elimination device of the cyclic frame, frame difference signals are decomposed into plural spatial frequency components in an Hadamard transformation circuit 105, a nonlinear processing is respectively performed in a nonlinar processing circuit 106 and they are coupled and transformed to original signals on a time base in an Hadamard inverse transformation circuit 107. Also, a movement detection circuit 108 for using two-dimensional low band components among Hadamard transformation components is provided and movement components are detected from the frame difference signals. In a coefficient circuit 109, a coefficient is controlled by the detected result of the movement detection circuit 108 and the coefficient is multiplied with the output signals of Hadamard inverse transformation and noise components are defined. The noise components are subtracted from input video signals. By the constitution, noise extraction corresponding to the feature of the input video signals is performed and high S/N improving effects are obtained without generating the picture quality degradation.