Detecting repetition in digital video

Abstract

There is provided a method of detecting repeated pictures in a sequence of video picture data, each picture of said video picture data comprising a plurality of macroblocks, the method comprising performing hierarchical motion estimation on the video picture data to provide best motion vectors for each macroblock, best motion vector sum of absolute difference values for each macro block and zero motion vector sum of absolute difference values for each macroblock, wherein the hierarchical motion estimation includes a plurality of levels, and said best motion vectors, best motion vector sum of absolute difference values and zero motion vector sum of absolute difference values for each macroblock are provided for at least a top level, providing a noise threshold value based upon the zero motion vector sum of absolute difference values from the top level of the hierarchical motion estimation, accumulating the best motion vector sum of absolute difference values for macroblocks having best motion vector sum of absolute difference values greater than the noise threshold value to provide a distortion value for the picture, and setting a repeat flag dependent upon the distortion value. An apparatus adapted to carry out the method, and a computer readable medium carrying instructions which, when executed by a computer, cause the computer to carry out the method are also provided.