Implementing Viewport Tile Extractor for Viewport-Adaptive 360-Degree Video Tiled Streaming

Because 360-degree video streaming has become significantly popular in the field of virtual reality, the viewport-adaptive tiled streaming technology for 360-degree video is emerging. This paper presents a viewport tile extractor (VTE) that is implemented on high-efficiency video coding (HEVC). The VTE extracts multiple tiles that represent the viewport of a user and merges them into one bitstream. The proposed system transmits the bitstream of high-quality tiles and the low-quality video bitstream of entire area to reduce both latency and bandwidth. The proposed method shows more than 16.98% of bjontegaard delta rate saving in terms of the luma peak signal-to-noise ratio, compared with the HEVC-compliant streaming method. Additionally, compared with the existing tiled streaming method, it achieves 66.16% and 69.79% saving of decoding memory and time consumption, respectively.