A content-adaptive wavelet-like transform for aliasing suppression in image and video compression

In the application of resolution scalable video coding, pure wavelet transforms offer attractive compression performance yet suffer from poor frequency rolloff, resulting in noticeable aliasing artifacts. In our previous work, we proposed a wavelet-based scheme which exploits spectral properties of natural images to achieve good antialiasing performance with a critically sampled transform. However, the scheme suffers from ringing artifacts and reduced energy compaction, which results in compression on par with Laplacian pyramids. In this paper we extend this scheme to be spatially adaptive. We find this achieves improvements over the non-adaptive method of up to 0.5 dB at 1 bpp, substantially reduces incidence of ringing artifacts and maintains the original property of aliasing suppression.