1. Zeqi Lai, Y. Charlie Hu, Yong Cui, Linhui Sun, Ningwei Dai
Furion: Engineering High-Quality Immersive Virtual Reality on Today’s Mobile Devices
Zeqi Lai, Y. Charlie Hu, Yong Cui, Linhui Sun, Ningwei Dai
Tsinghua University
*Purdue University
MobiCom 2017

2. Furion
Background
Motivation: understanding the QoE gap between goal and reality
Furion design
Performance evaluation
Conclusion

3. Furion Background Growing market penetration of VR
Headset, Controller, Renderer
QoE requirements
Good responsiveness(e.g. latency < 16ms)
High-Quality visual effects
Mobility
Today`s high-quality VR systems are tethered
Can we enable high-quality VR on today`s mobile device and wireless network?

4. Furion
Background
Motivation: understanding the QoE gap between goal and reality
Furion design
Performance evaluation
Conclusion

5. Furion Local Rendering Lower BRISQUE value, better visual quality.
Visual quality ↑, FPS↓(per-frame latency ↑)
Conclusion: local rendering is not doable

6. Furion Remote Rendering
Rendering frames by a desktop(GTX 1080) and streaming frames to the phone via ac WLAN (available peak bandwidth :≈ 400Mbps)
Transferring a high-quality frame takes about 200ms

7. Furion Will future hardware help?
Future CPU/GPU is unlikely to help because of the power constraint.

8. Furion Will future networks help?
Also unlikely to directly help due to the significant packet processing overhead on commodity phones
400Mbps TCP throughput already involves 27% CPU on Google pixel phone.
Streaming high-quality VR frames in high
FPS requires about 6Gbps throughput
[MoVR, NSDI 2017]

9. Furion
Background
Motivation: understanding the QoE gap between goal and reality
Furion design
Performance evaluation
Conclusion

10. Furion
Remote rendering + video compression
M: MJPEG, H: H.264, V: VP9

11. Furion Remote rendering + video compression M: MJPEG, H: H.264, V: VP9
How to get to 16ms?

12. Furion Key insight I: Key insight II:
Mostly, VR content can be divided into foreground interactions and background environment.
Key insight II:
Interactions and environment have contrasting predictability and rendering workload.

13. Furion Cooperative rendering How can we reduce 48ms?
Mobile GPU -> interactions (about 12ms)
Remote GPU -> environment (about 48ms)
Combine them on phone
How can we reduce 48ms?

14. Furion
The virtual world is discretized, and user movement is continuous and predictable
Leveraging movement delay to pre-fetch adjacent frames
Using pre-rendered and pre-encoded panoramic frames to batch all possible orientations.

15. Furion Decoding an encoded panoramic pictures takes 40ms
Use parallel decoding.

16. Furion
Background
Motivation: understanding the QoE gap between goal and reality
Furion design
Performance evaluation
Conclusion

17. Furion Performance evaluation
Visual quality(the higher SSIM, the better) and FPS

18. Furion
Performance evaluation
Responsiveness

19. Furion
Performance evaluation
Resource usage

20. Furion
Conclusion
Developed Furion, a VR framework that enables high-quality, immersive mobile VR on today`s mobile phone and wireless network.
Furion design is based on a split rendering architecture leveraging a key insight about VR, the contrasting of foreground interaction and background environment.
Furion achieves acceptable QoE on commodity phones.