  This paper reports on a subjective quality evaluation of static point clouds
encoded with the MPEG codecs V-PCC and G-PCC, the deep learning-based codec
RS-DLPCC, and the popular Draco codec. 18 subjects visualized 3D
representations of distorted point clouds using a Head Mounted Display, which
allowed for a direct comparison with their reference. The Mean Opinion Scores
(MOS) obtained in this subjective evaluation were compared with the MOS from
two previous studies, where the same content was visualized either on a 2D
display or a 3D stereoscopic display, through the Pearson Correlation, Spearman
Rank Order Correlation, Root Mean Square Error, and the Outlier Ratio. The
results indicate that the three studies are highly correlated with one another.
Moreover, a statistical analysis between all evaluations showed no significant
differences between them.
