基于H.264的网络视频电话

H.264-based Network Video Phone

视频编码标准H.264以其更高的压缩效率以及网络友好的设计为网络视频应用提供了新的编码方法。但是,更先进的H.264的编码过程需要非常大的计算量。该文通过调节H.264的编码配置参数获得了影响编码复杂度的主要因素,并以不到0.5db的编码质量损失和13.2%编码效率损失使编码速度加快了45倍。针对网络视频电话的画面特点,该文提出了一种新的灵活宏块序构造用于差错复原,与常用的片交织方案相比,以牺牲2.5%左右的编码效率为代价获得了更好的差错掩藏效果。

Video coding standard H.264 provides a new approach to network video applications for its enhanced compression performance and network-friendly design. However, the encoding process of more advanced H.264 is computation-intensive. This paper acquires the main factors influencing encoding complexity through adjusting the encoding configuration parameters of H.264, and improves encoding speed by 45 times at a cost of encoding efficiency degradation by 13.2% and encoding quality degradation within 0.5 db. In consideration of the image feature of network video phone, a new flexible macroblock order form is proposed. Comparing with common slice interleaving scheme, it achieves better error concealment effect at the cost of 2.5% encoding efficiency.