Adaptive Up-Sampling Method Using DCT for Spatial Scalability of Scalable Video Coding

Abstract

In the incoming amendment of H.264/AVC for scalable video coding (SVC), down and up-samplings in a spatial domain are incorporated for spatial scalability. A new two-fold up-sampling method is proposed for SVC. The proposed up-sampling method is based on a combination of the forward and backward type-II discrete cosine transform (DCT). As the proposed up-sampling kernel has various symmetries for efficient computation, a fast algorithm of type-II DCT-based up-sampling method is also proposed. For further improvement of the up-sampling performance, an adaptive filtering method in the type-II DCT up-sampling is introduced, which applies different weighting parameters to DCT coefficients. Even as this adaptive method is applied, the up-sampling operation in the decoder has the same computational complexity as the fixed weighting method. The proposed adaptive up-sampling method shows a much improved PSNR in comparison with the recent H.264 SVC up-sampling method.