Pixel similarity based computation and power reduction technique for H.264 intra prediction

H.264 intra prediction algorithm has a very high computational complexity. This paper proposes a pixel similarity based technique for reducing the amount of computations performed by H.264 intra prediction algorithm and therefore reducing the power consumption of H.264 intra prediction hardware significantly. The proposed technique performs a small number of comparisons among neighboring pixels of the current block before the intra prediction process. If the neighboring pixels of the current block are similar, the prediction equations of H.264 intra prediction modes are simplified for this block. The proposed technique reduces the amount of computations performed by 4x4 luminance, 16x16 luminance, and 8x8 chrominance prediction modes up to 68%, 39%, and 65% respectively with a small comparison overhead. The proposed technique does not change the PSNR for some video frames, it increases the PSNR slightly for some video frames and it decreases the PSNR slightly for some video frames. We also implemented an efficient 4x4 intra prediction hardware including the proposed technique using Verilog HDL. The proposed technique reduced the power consumption of this hardware up to 57%.