EFFICIENT LIVE VIDEO STREAMING FOR WIRELESS MULTIHOP NETWORKS

The Hong Kong University of Science and Technology
Department of Computer Science and Engineering


PhD Thesis Defence

Title: "EFFICIENT LIVE VIDEO STREAMING FOR WIRELESS MULTIHOP NETWORKS"

By

Mr. Bo ZHANG


Abstract

With advances in networking, storage and processing capabilities, mobile 
devices can now share videos with each other. In this thesis,we study 
howto achieve efficient live streaming among cooperative wireless devices. 
In such a mobile peer-to-peer (P2P) streaming network, mobile stations 
(MSs) relay their received packets in a multi-hop manner by means of 
broadcasting using a secondary channel (such as Wi-Fi or Bluetooth). Such 
network greatly increases network scalability by multiplying its available 
bandwidth, extends its coverage and improves its recovery efficiency.

The design of the broadcast overlay is crucial to streaming efficiency in 
terms of achievable streaming rate. We hence first propose a novel overlay 
called LocalTree which seeks to minimize the total network traffic while 
covering all the clients. LocalTree takes advantage of stable clusters of 
MSs to construct streaming overlay. It combines the strengths of both 
structured and unstructured overlay designs, and is simple and effective.

We next investigate live free viewpoint video (FVV) streaming in a 
wireless cooperative multihop network. An FVV is composed of a large 
number of camera-captured anchor views, with virtual views (not captured 
by any camera) rendered from their nearby anchors using techniques such as 
depth-image-based rendering (DIBR). Given limited wireless bandwidth at 
the MSs, we seek to maximize the received video quality (i.e., minimize 
distortion). We propose a distributed algorithm called PAFV (Peer-Assisted 
Freeview Video), which achieves scalability and high video quality.

Packet loss is inevitable in wireless video streaming due to dynamic 
channel condition. To address this, we finally study P2P cooperative error 
recovery for video broadcasting. In our system, an MS may generate some 
parity packets and share them to its neighbors. An important problem is to 
minimize the total number of parity packets generated while achieving a 
certain residual loss rate. We propose BOPPER (Broadcast-based P2P Error 
Recovery), a novel and fully distributed algorithm to achieve low residual 
loss.


Date:			Wednesday, 10 August 2016

Time:			2:00pm - 4:00pm

Venue:			Room 5564
 			Lifts 27/28

Chairman:		Prof. Kai Tang (MAE)

Committee Members:	Prof. Gary Chan (Supervisor)
 			Prof. Kai Chen
 			Prof. Qian Zhang
 			Prof. Lu Fang (ECE)
 			Prof. Yiu-Bun Lee (Inf. Engg., CUHK)


**** ALL are Welcome ****