Abstract
Omnidirectional video encoding and delivery are rapidly evolving fields, where choosing an efficient representation for storage and transmission of pixel data is critical. Given that there are a number of projections (pixel representations), a projection independent measure is needed to evaluate the merits of different options. We present a technique to evaluate projection quality by rendering virtual views and use this to evaluate three projections in common use: Equirectangular, Cubemap, and Equi-Angular Cubemap. Through evaluation on dozens of videos, our metrics rank the projection types consistently with pixel density computations and small scale user studies.