Fast coding tree unit decision for HEVC intra coding

The Quad-tree structure in HEVC contributes to significant coding efficiency improvement, especially for high resolution videos. However, its recursive representation increases the coding complexity as well. This paper brings forward a fast coding tree unit algorithm to speed up the original intra coding in HEVC. By analyzing the texture of the CU, to filter out some unnecessary CU candidates. In the paper, two variables are used to evaluate the texture of the CU, that is the sobel gradient and MAD value. Combined these two values, encoding of some CUs can be skipped. Experimental results show that the algorithm obtains around 30% of time reduction with nearly unchanged PSNR and bitrate stays almost the same compared with the original HEVC intra coding.