Abstract: A method and apparatus for updating motion vector memories used for prediction of motion vectors in a video compression coding/decoding method and system. For a frame composed of N macroblocks in the horizontal direction, only (2N+1) motion vector memories are used to store all motion vectors necessary to motion Prediction, and only three memories per macroblock are used to update motion vectors, thereby reducing the size of a circuitry, the amount of computation and the amount of power consumed.

Abstract: A motion vector estimation apparatus in a digital video coding system and a method thereof. More particularly, the present invention relates to a motion estimation method and apparatus for, prior to a motion vector estimation operation, determining whether to perform it and selectively performing the motion vector estimation operation in accordance with the determined result, thereby reducing the coding time period and the amount of power consumed.

Abstract: A method and apparatus for compression transformation and inverse transformation of a digital image wherein, for the transformation and inverse transformation, a determination is made as to whether all input data values are 0, and an unnecessary transform process is skipped if all the input data values are determined to be 0, thereby reducing power consumption resulting from the unnecessary transform process. The present method and apparatus can very simply be implemented and minimize power consumption. Therefore, the present invention is significantly effective in implementing a low-power video codec essential to mobile communication terminals.

Abstract: A motion estimation method and device for selecting a final motion vector to be coded, in consideration of a zero vector and a predicted motion vector as well as a motion vector having a minimum error, thereby increasing a video coding efficiency.