Efficient variable length decoding using N-bit code table for multi-format video applications

In this paper, the method to generate and use a lookup table from a variable length codes (VLC) table, the so-called N-bit code table is described. The original VLC table is stored in a tree structure, and then transformed to the N-bit code table through the process presented on the paper. The proposed method can be applied to any VLC table regardless of the video formats. The implementation of the method accelerating a general RISC reduces the number of memory access from 48.3% up to 95.17% compared to the RISC without the implementation when applied to VLC tables of H.264/AVC.