IMAGE FORMAT CONVERTING APPARATUS AND METHODS IN VIDEO SIGNAL PROCESSING SYSTEM

An apparatus for converting image format and methods thereof in a video signal processing system. The apparatus includes an analog-to-digital converting unit for sampling original color signals at predetermined intervals and converting the sampled signals into digital signals; a color-space converting unit for converting a digital signal of the analog-to-digital converting unit into a brightness signal and a color tone signal and for outputting these signals; a storage unit for storing a look-up table representing linear interpolation coefficients converted in response to a conversion of an image size; a horizontal scaling unit for linearly interpolating one cycle of the brightness signal and color tone signal in response to a conversion of image size with reference to the look-up table of the storage unit, and for horizontally scaling by repeatedly outputting the outcome linearly-interpolated; a line memory unit for momentarily storing a horizontally scaled signal by the horizontal scaling unit; a vertical scaling unit for interpolating a cycle of a horizontal scaling signal provided by the line memory unit in response to the conversion of the image size with reference to the look-up table, thereby vertically scaling by repeatedly outputting the linearly interpolated data; and a frame memory unit for storing signals vertically and horizontally-scaled by the vertical scaling unit and for converting vertical and horizontal frequencies of the vertical and horizontal scaled signals.