1. A method of sample adaptive offset (SAO) compensation of reconstructed video data, the method comprising: receiving first video data corresponding to the reconstructed video data or reconstructed-and-deblocked video data; determining a category for a current pixel of the first video data according to a pixel intensity relation between the current pixel and one or more neighboring pixels, wherein the relation between the current pixel and said one or more neighboring pixels is based on a sign function; storing the pixel intensity relation between the current pixel and said one or more neighboring pixels; compensating the current pixel using an offset value associated with the category to generate a compensated current pixel; and replacing the current pixel of the first video data by the compensated current pixel after said storing the pixel intensity relation between the current pixel and said one or more neighboring pixels without a need for completion of compensating all of said one or more neighboring pixels.