Localized Multiple Adaptive Interpolation Filters with SinglePass Encoding Adaptive interpolation filtering (AIF) algorithms have been proposed to enhance the hybrid video coding scheme recently. Although these algorithms can improve coding efficiency significantly, their encoders suffer huge increase in complexity in terms of latency and memory access due to its inherent multipass encoding structure. In this paper, we propose a novel singlepass solution for these algorithms, which allows optimal selection among different AIF filters. In this solution, timedelayed AIF filters are used to achieve singlepass encoding. Localized ratedistortion (RD) selection is used to compensate the possible coding loss by using timedelayed filters. Experimental results show that the proposed method is efficient for All AIF techniques in current ITUTSG16 reference software. By using the proposed method, singlepass encoding with multiple AIF filters can be achieved while maintaining similar coding efficiency as the multipass AIF.

Advances in hybrid video coding Hybrid video coding is known for a long time and is applied in all video coding standards such as MPEGx or H.26x. This paper shows that there is still enough potential for further coding efficiency improvements. The paper starts with an overview of stateoftheart hybrid video coding schemes such as H.264AVC. Thereafter, our advances on main building blocks of H.264AVC are presented that significantly improve the coding efficiency. For instance, intra prediction is improved by changing scan directions and thus providing better reference pixels for specific prediction directions. Adaptive filtering and high precision motion compensation improves the motion compensated prediction. Furthermore, the combination of transformation, quantization, and entropy coding of the prediction error is improved using an advanced frequency selective coding technique. With the transmission of postfilter hints it is possible to design a Wiener postfilter that significantly enhances the picture quality. Finally, texture synthesis techniques are used to improve the subjective quality for specific textures with homogenous statistical characteristics. This paper presents our abovementioned techniques in detail. Depending on the input sequence and the bit rate, the objective andor subjective gains compared to H.264AVC are quite significant.