  Point cloud video has been widely used by augmented reality (AR) and virtual
reality (VR) applications as it allows users to have an immersive experience of
six degrees of freedom (6DoFs). Yet there is still a lack of research on
quality of experience (QoE) model of point cloud video streaming, which cannot
provide optimization metric for streaming systems. Besides, position and color
information contained in each pixel of point cloud video, and viewport distance
effect caused by 6DoFs viewing procedure make the traditional objective quality
evaluation metric cannot be directly used in point cloud video streaming
system. In this paper we first analyze the subjective and objective factors
related to QoE model. Then an experimental system to simulate point cloud video
streaming is setup and detailed subjective quality evaluation experiments are
carried out. Based on collected mean opinion score (MOS) data, we propose a QoE
model for point cloud video streaming. We also verify the model by actual
subjective scoring, and the results show that the proposed QoE model can
accurately reflect users' visual perception. We also make the experimental
database public to promote the QoE research of point cloud video streaming.
