A More Efficient and Video Friendly Spatial Resizing Algorithm

Arbitrary spatial resizing of compressed video is a useful transcoding operation that can be used to match the video stream to a low bandwidth channel or to end user devices with a different resolution from that of the original source material. By performing this transcoding in the compressed domain the computational cost of the operation can be minimized. Our proposed algorithm resizes a video stream by modifying functional blocks in an existing transcoding architecture to permit spatial resizing. In order for the algorithm to function, a new motion compensation operation suitable for resized video was derived. The algorithm retains the advantages of permitting tradeoffs between computational cost and final quality while re sizing by any rational fraction. Additionally, the algorithm operates on an arbitrary supporting area and complements motion compensation.