Fast Algorithm of the 2-D 4x4 Inverse Integer Transform for H.264/AVC

A new fast two-dimension 4times4 (2-D 4times4 ) inverse integer transform algorithm is presented in this paper. The new algorithm reduces the addition and shift operations for the inverse transform greatly by using the two points: one is the regularities of the basic images; another is the characteristic of the post- transform data of the practical videos. By taking examples for several standard video clips, the new algorithm is compared with the existed influential fast algorithms. The experimental results indicate that the new algorithm needs 12.7838 addition operations and 1.69536 shift operations averagely which are much less than the operations of the existed influential fast algorithms. Moreover, the proposed direct 2-D algorithm is fit for parallel computing process.