Chroma upsampling for YCbCr 420 videos

We proposed a novel chroma upsampling scheme for YCbCr 420 videos. In a state-of-the-art work, the upsampling is performed by simply duplicating the stored U and V values in YCbCr 420 for 4 copies and saving to the corresponding locations in YCbCr 444. In the proposed method, instead of directly copying the current values, we consider their neighboring chroma values as the weights to redistribute the total energy. The experimental results show that the proposed chroma upsampling method is better than the state-of the-art method in all the tested videos in terms of CPSNR; the average gain is 0.13 dB.