Abstract: An apparatus for coding an arbitrarily shaped object region of a video signal comprises a processing block decision circuit. The processing block decision circuit selects a processing block encompassing the object region based on the shape information to generate the processing block signal and processing block position data, wherein the processing block includes P.times.Q subblocks, P and Q being positive integers. The apparatus also includes a subblock rearrangement circuit. The subblock rearrangement circuit rearranges the subblocks of the processing block to generate a rearranged processing block having a minimum number of the subblocks encompassing the object region and position information representing positions of the rearranged subblocks. A transform coding circuit then converts the rearranged processing block on a subblock-by-subblock basis to a transform coded video signal to be transmitted.