ADAPTIVE PRUNED 4 × 4 DCT ALGORITHM FOR H.264

A new integer 4times4 transform is adopted in the new video coding standard H.264/AVC. To reduce the computation load of the new transform, the SSAVT model for 8times8 transform is applied into H.264 4times4 transform with some modifications. Then, three classes of pruned block are defined and the corresponding simplified butterfly computation processes are designed. Furthermore, a fast DCT algorithm is proposed, with which we can identify the class of pruned block, so as to adopt simplified computation, with the help of modified model for 4times4 transform. Simulation results show that the proposed DCT algorithm saves about average 55% computation of DCT compared with full computation