METHOD, APPARATUS AND SYSTEM FOR ENCODING AND DECODING A TRANSFORMED BLOCK OF VIDEO SAMPLES

A system and method of decoding a coding unit in an image frame from a bitstream. The method comprises determining a size of the coding unit from the bitstream; and dividing the image frame into a plurality of equally sized processing regions, each of the equally sized processing regions being a block processed during a single stage of a pipeline decoding the bitstream. If the coding unit overlaps a boundary between the determined processing regions, the method comprises selecting a transform size for the coding unit from a plurality of transform sizes, the transform size being selected to fit within the coding unit and being different in size to the processing regions; and decoding the coding unit by applying an inverse transform to residual coefficients of each transform unit in the coding unit, each of the transform units being of the selected transform size.