Enhanced Adaptive Interpolation Filters for Video Coding

H.264/AVC uses motion compensated prediction with fractional-pixel precision to reduce temporal redundancy of the input video signal. It has been shown that the Adaptive Interpolation Filter (AIF) framework [3] can significantly improve accuracy of the motion compensated prediction. In this paper, we present the Enhanced Adaptive Interpolation Filters (E-AIF) scheme, which enhances the AIF framework with a number of useful features, aimed at both improving performance and reducing complexity. These features include the full-pixel position filter and the filter offset, the radial-shaped 12-position filter support, and a RD-based filter selection. Simulations show that E-AIF can achieve up to 20% bit rate reduction compared to H.264/AVC. Compared to all other AIF schemes, E-AIF further reduces the bit rate by up to 6%, and demonstrates the highest performance consistently.