Fast Mode Decision Algorithm for Enhancement Layer of Spatial and CGS Scalable Video Coding

The scalable video coding is an effective solution to fulfil the different requirements in modern video transmission system. Though the coding efficiency is high, the computational complexity is expensive. This paper presents a proposed algorithm to reduce the encoding time of enhancement layer through probability analysis. Firstly two classes are defined, and the Bayes Classifier decides whether the current macroblock belongs to Big Block class or Small Block class. Then an early termination strategy is checked for ignoring some inter modes. When inter-layer residual prediction is used, the optimal inter mode is set as the best inter mode of co-located macroblock in base layer. For the intra modes, the INTRA_16x16 is skipped based on statistical data. Experiment results show that the proposed algorithm reduces computational complexity with negligible video quality loss and bit rate increment when compared with reference software and other methods.