A fast down-sampling method for arbitrary-ratio spatial scalability based on type-II DCT

In a scalable video coding (SVC), spatial down/up-sampling of video sequences is an essential process for spatial scalability. We propose an arbitrary-ratio spatial down-sampling method based on the type-II DCT, with which down-sampling of H.264 SVC can be efficient. Simple windowing operation in the DCT domain is efficiently embedded in the proposed down-sampling method for aliasing reduction. A fast algorithm for arbitrary-ratio down-sampling is introduced with matrix decomposition and fast DCT. It achieves 80 % reduction of computation complexity in comparison with the direct matrix calculation.