An efficient content-adaptive MC 3D-DWT with enhanced spatial and temporal scalability

In this paper we propose a novel, adaptive method for motion compensated 3D wavelet transformation (MC 3D-DWT) of video. The proposed method overcomes problems of ghosting and nonaligned aliasing artifacts which can arise in regions of motion model failure, when the video is reconstructed at reduced temporal or spatial resolutions. Previous MC 3D-DWT structures either take the form of a MC temporal DWT followed by a spatial transform ("t+2D"), or perform the spatial transform first, limiting the spatial frequencies which can be jointly compensated in the temporal transform and hence limiting the compression efficiency. Essentially, the proposed transform continuously adapts itself between these two extremes, based on information available within the compressed bit-stream. Experimental results indicate that the proposed adaptive transform significantly reduces the cost in compression efficiency required to achieve high quality spatial and temporal scalability.