Perceptual quality evaluation of variable resolution VVC video coding using RPR

In this paper we analyze the perceptual performance of encoding in reduced resolution at challenging bitrates on 4k content by means of reference picture resampling tool in VVC in comparison with encoding in source resolution. The subjective testing shows that adaptively encoding in reduced resolution based on GOP-based reference picture resampling encoder control present in the VVC reference software is always better or equal to the anchor given a 95% confidence interval. The objective metrics based on PSNR and MS-SSIM also both indicate a gain for these sequences.