Fast Intra Mode Decision Algorithm Based on Texture Feature for H.264/AVC

As the newest video coding standard, H.264/AVC uses the rate distortion optimization(RDO) method to select the optimal coding mode after the calculation of all the possible modes. The computational complexity is increased drastically, so it isn't fit for real time encoding and hardware design. In this paper, we propose a fast intra mode decision algorithm based on texture feature for H.264/AVC. First of all, we speculate the smooth degree of a macroblock(MB)'s texture according to the variance value of some pixels, then only choose the intra luma 16 x 16 block for the smooth texture or only choose the intra luma 4 x 4 block for the complex texture. Secondly, we choose part modes of intra 4 x 4 block or intra 16 x 16 block based on direction of texture. The experimental result show our algorithm can reduce the encoding time obviously with little change of PSNR and Bit-rate.