Page 45 - ITU Journal, ICT Discoveries, Volume 3, No. 1, June 2020 Special issue: The future of video and immersive media

ITU Journal: ICT Discoveries, Vol. 3(1), June 2020

particular viewpoint to the other viewpoint. The the OMAF standard specification. We introduced
content creator can analyze the content from all the the main functionalities of these two features and
viewpoints in order to determine the orientation of a highlighted the new enabled use cases. These make
particular person or object of interest for obtaining the new OMAFv2 standard even more appealing for
their orientation in each viewpoint at a given time. In content producers, service providers and device
Fig. 7, VO1-VPi represent the viewport orientations of manufacturers. Other features in the MPEG
the object of interest O1 from viewpoints VP1 and VP2. standardization pipeline include the support of
Similarly, for other objects of interest O2 and O3. This “limited” 6DoF content (a.k.a. 3DoF+), which
information can be utilized by the player application enhances even further the spectrum of possible
to select the object of interest in the current viewport applications.
and its orientation in the viewpoint where the user
wishes to switch. The selection of the object of interest ACKNOWLEDGEMENT
can be performed interactively by the user or based on The authors would like to thank all colleagues in the
a preset application implementation criterion, e.g., the MPEG committee who have contributed to develop
selection of the object which is in the center of the the OMAF version 2 standard specification.
viewport. This type of switching facilitates performing
a viewpoint switch such that the object or person of REFERENCES
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This paper presented an overview of two of the new Efficient Real-Time Video-in-Video Insertion
features included in the second edition of the MPEG into a Pre-Encoded Video Stream for the
Omnidirectional MediA Format (OMAF) standard, H.264/AVC, IEEE International Conference on
namely, overlays and mutli-viewpoints. The MPEG Imaging Systems and Techniques,
committee is about to finalize the second edition of Thessaloniki, Greece.

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