1. In digital television systems having conditional replenishment bit-rate compression, a method for detecting moving points in a television image, the method comprising: splitting the image into blocks of N.times.M points, the points of an N.times.M image block being located at intersections of N lines and M columns of the image; measuring the inter-image differences between the luminance and chrominance values for each point of each of the N.times.M image blocks for obtaining N.times.M inter-image differences for each N.times.M block; applying to each inter-image difference N.times.M block an orthogonal transformation for converting the N.times.M inter-image differences to N.times.M coefficients; comparing the absolute values of the coefficients of a block of N.times.M points with at least one predetermined reference threshold for ascertaining the movement of points located at the center of the block of N.times.M points; whereby the center points are ascertained as moving when the absolute value of at least one of the coefficients is higher than the at least one predetermined reference threshold.