To reduce the transmission bit rate or storage capacity, many image compression (coding) techniques have been developed for a broad spectrum of applications. In this study, a new block-based motion-compensated image sequence coding scheme is proposed. In the proposed approach, the blocks of an image frame within an image sequence are segmented by an illumination-independent change detection algorithm and then clustered into moving and stationary parts by a labeling algorithm. Only the motion displacement information of the moving parts is required to be computed and transmitted whereas the stationary parts are ignored. The motion displacement dependency among the moving blocks within each moving part is employed so that both the motion displacement computations and the number of bits required for transmission are greatly reduced. Also, the motion displacement information is encoded by the proposed adaptive run-length coding scheme. Based on the experimental results using two test image sequences, "Miss America" and "Salesman," in terms of several performance measures, the proposed approach is superior to two existing approaches.