Page 104 - 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

Each version of libaom software since March 2018 versatility by meeting the requirements of higher
has improved in running time at constant quality. compression efficiency on any type of content
The ETM runtimes are lower than the VTM ones, including 360° video for Virtual Reality (VR), High
which can be explained by a lower compression Dynamic Range (HDR), and computer graphics
performance (less complex algorithms) but also by (Screen Content and Gaming). Furthermore
a different code base. The development process of scalability and RPR features provide tools for
VVC was driven by compression efficiency but also network bandwidth adaptation. The new
by considering implementability constraints, sub-picture feature also offers support of the
mainly on the decoder side. It can be observed that region-wise random access feature, which can be of
the decoder runtime (Table 11) is limited to particular interest for viewport dependent
1.9 times the HM decoder. However, no specific streaming of 360° video. These video coding
effort was put on the reference encoder runtime standards have different announced licensing terms
(Table 10), which is 13 times the HM encoder with that could impact their deployment. AV1 is
the VTM8 software, as encoding algorithms are publicized to be royalty-free. The EVC contributors
non-normative. are claiming licensing terms will be available less
than two years after the standard publication. VVC
6. CONCLUSION should follow the path of past video coding
standards developed jointly by ITU-T, ISO and IEC
The evolution of video compression has until now such as H.264/AVC and H.265/HEVC. These
always been done incrementally, by building on top standards have been successfully deployed as
of the previous generation of video coding reported in [19] for HEVC.
standards. The latest video coding solutions
designed in ITU-T VCEG, ISO/IEC MPEG, and AOM
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