Had You Looked Where I'm Looking? Cross-user Similarities in Viewing - PowerPoint PPT Presentation

Had You Looked Where I'm Looking? Cross-user Similarities in Viewing Behavior for 360 - degree Video and Caching Implications Niklas Carlsson, Linköping University Derek Eager, University of Saskatchewan Proc. ACM/SPEC ICPE , April 2020

Before I start ...

The 360-degree experience ... eractive services over the

The 360-degree experience ... • Put the user in control of their experience • Opportunity to revolutionize the viewing experience eractive services over the

Highly bandwidth intensive ... • 360-degree video streaming highly bandwidth intensive • Important to identify and understand bandwidth saving opportunities

Saving bandwidth ... viewport • Users only see what is in the viewport • Many techniques prioritize the region visible to the user

Uncertainty in both ... … and want to avoid stalls ... eractive services over the

HAS/DASH + Til iling

HTTP-based Adaptive Streaming (H (HAS) • HTTP-based adaptive streaming – Video is split into chunks – Each chunk in multiple bitrates (qualities) – Clients adapt quality encoding based on buffer/network conditions

HTTP-based Adaptive Streaming (H (HAS) Chunk4 Chunk5 Chunk2 Chunk3 Chunk1 • HTTP-based adaptive streaming – Video is split into chunks – Each chunk in multiple bitrates (qualities) – Clients adapt quality encoding based on buffer/network conditions

360 HAS with tiles “Chunk 1” • In addition to chunks, we have – Tiles of different quality in each direction • Clients adapt quality encoding of each chunk and tile based on both • buffer/network conditions, and • expected view field

360 HAS with tiles “Chunk 1” “Chunk 2” “Chunk 3” “Chunk 4” • In addition to chunks, we have – Tiles of different quality in each direction • Clients adapt quality encoding of each chunk and tile based on both • buffer/network conditions, and • expected view field

Contributions • Trace-driven analysis of caching opportunities in this context ... • We present the first characterization of • the similarities in the viewing directions of users watching the same 360° video, • the overlap in viewports of these users (both instantaneously and on a per- chunk basis), and • the potential cache hit rates for different video categories and network conditions. • Results provide insights into the conditions under which overlap can be considerable and caching effective, and can inform the design of new caching system policies tailored for 360° video. Addressing both these uncertainties in simultaneously results in a p

Almquist et al. "The Prefetch Aggressiveness Tradeoff in 360 Video Streaming", Proc. ACM MMSys, 2018. Head movement traces • Oculus rift • YouTube 360 videos with 4K resolution • Five categories • Rides: “virtual ride ...” • Exploration: “no particular focus ...” • Static focus: “main focus of attention static ...” • Moving focus: “object of attention moves ...” • Miscellaneous: “unique feel ...” • Focus on “representative” videos • Viewed by 32 views per video • Rest got 8-13 views per video

Almquist et al. "The Prefetch Aggressiveness Tradeoff in 360 Video Streaming", Proc. ACM MMSys, 2018. Head movement traces Rides • Oculus rift • YouTube 360 videos with 4K resolution • Five categories Exploration • Rides: “virtual ride ...” • Exploration: “no particular focus ...” • Static focus: “main focus of attention static ...” • Moving focus: “object of attention moves ...” Static focus • Miscellaneous: “unique feel ...” • Focus on “representative” videos • Viewed by 32 views per video • Rest got 8-13 views per video Moving focus 2 5

Had You Looked Where I'm Looking? Cross-user Similarities in Viewing - PowerPoint PPT Presentation

Had You Looked Where I'm Looking? Cross-user Similarities in Viewing Behavior for 360 - degree Video and Caching Implications Niklas Carlsson, Linkping University Derek Eager, University of Saskatchewan Proc. ACM/SPEC ICPE , April 2020 Before I

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Had You Looked Where I'm Looking? Cross-user Similarities in Viewing - PowerPoint PPT Presentation

Had You Looked Where I'm Looking? Cross-user Similarities in Viewing Behavior for 360 - degree Video and Caching Implications Niklas Carlsson, Linkping University Derek Eager, University of Saskatchewan Proc. ACM/SPEC ICPE , April 2020 Before I

Looked After Children GP PLT training sessions July 2020 Kent and Medway CCG Looked After

Audit Objectjve This audit looked at whether regional rail upgrades are improving rural freight

Overview Our starting point was not the consultation options The future of We looked at

Introduction to XML What markup languages have you used (or looked at) (or heard of)? What

The Education of Children Looked After by London Borough of Hounslow A Report for Corporate

Out of Borough Placements for Looked After Children Current Profile of Placements At the end

Who gets looked after? Inequality and childrens services . Paul Bywaters, Professor of Social

THEORY U AND TRANSFORMATIONAL DIALOGUE The Blind Spot in Leadership We have looked at what

Revelation 1 3 Revelation 4:1 5 After this I looked, and there before me was a door

Revelation 14 Becoming Closer Reprise: the 144,000 (Rev 14:1-5 NIV) Then I looked, and there

The newly created EBP committee looked for their first project

Introduction The classifiers weve looked at up to this point ignore the sequential aspects of

Revelation The Message of Revelation John (circa 96 AD) After this I looked, and there before me

As always, there is lots to cover and not much time. 1 Have you ever looked at your maintenance

POSTULATE SAS I NTRODUCTION Having looked at SSS and SAS postulates, we would like to proceed

This audit looked at whether the Department of Educatjon and Training (DET), allocates funding to

This audit looked at whether the state is efgectjvely managing its exposure to liabilitjes

INSPIRING IMAGERY These are my favourite images that I looked at as a starting point. I took

This audit looked at whether the fraud and corruptjon controls over personnel security are

Conquest Martyrs Rev. 6:12, I looked when He opened the sixth seal, and behold, there was a

Last week 1. We talked about some Hilbert space facts you knew from before. 2. We looked at the

Manipulation Techniques &amp; Visualization Sanity Check Have you looked at the notes and

Technology and Society - A Timeline Dr. Gabriela Avram Two weeks ago p We looked at how

The Core of Our Existence God chose to create Man in His own image why? God then looked at Man

Manipulation Techniques & Visualization Sanity Check Have you looked at the notes and