Adaptive Content-Aware Scaling for Improved Video Streaming

Streaming video applications on the Internet generally have very high bandwidth requirements and yet are often unresponsive to network congestion. In order to avoid congestion collapse and improve video quality, these applications need to respond to congestion in the network by deploying mechanisms to reduce their bandwidth requirements under conditions of heavy load. In reducing bandwidth, video with high motion will look better if all the frames are kept but the frames have low quality, while video with low motion will look better if some frames are dropped but the remaining frames have high quality. Unfortunately current video applications scale to fit the available bandwidth without regard to the video content. In this thesis, we present an adaptive content-aware scaling mechanism that reduces the bandwidth occupied by an application by either dropping frames (temporal scaling) or by reducing the quality of the frames transmitted (quality scaling). We have designed a streaming video client and server with the server capable of quantifying the amount of motion in an MPEG stream and scaling each scene either temporally or by quality as appropriate, maximizing the appearance of each video stream. We have evaluated the impact of content-aware scaling by conducting a user study wherein the subjects rated the quality of video clips that were first scaled temporally and then by quality in order to establish the optimal mechanism for scaling a particular stream. We find that content-aware scaling can improve video quality by as much as 50%. We have also evaluated the practical impact of adaptively scaling the video stream by conducting a user study for longer video clips with varying amounts of motion and available bandwidth. We find that for such clips also the improvement in perceptual quality on account of adaptive content-aware scaling is as high as 30

Adaptive Video Streaming using Content-Aware Media Scaling

Streaming video applications on the Internet generally have very high bandwidth requirements and yet are often unresponsive to network congestion. In order to avoid congestion collapse and improve video quality, these applications need to respond to congestion in the network by deploying mechanisms to reduce their bandwidth requirements under conditions of heavy load. In reducing bandwidth, video with high motion will look better if all the frames are kept but the frames have low quality, while video with low motion will look better if some frames are dropped but the remaining frames have high quality. Unfortunately, current video applications scale to fit the available bandwidth without regard to the video content. In this paper, we present a content -aware scaling mechanism that reduces the bandwidth occupied by an application by either dropping frames (temporal scaling) or by reducing the quality of the frames transmitted (quality scaling). We have designed a streaming video client and server with the server capable of quantifying the amount of motion in an MPEG stream and scaling each scene either temporally or by quality as appropriate, maximizing the quality of each video stream. We have evaluated our setup by conducting a user study wherein the subjects rated the quality of the video clips that were first scaled temporally and then scaled by quality in order to establish the optimal mechanism for scaling a particular stream. We find that our content-aware scaling can improve perceived video quality by as much as 50%. We have also evaluated the practical impact of adaptively scaling the video stream by conducting a user study for longer video clips with varying amounts of motion and available bandwidth. We find that for such clips the improvement in perceptual quality on account of adaptive content-aware scaling is as high as 30%

QoE in Pull Based P2P-TV Systems: Overlay Topology Design Tradeoff

Abstract—This paper presents a systematic performance anal-ysis of pull P2P video streaming systems for live applications, providing guidelines for the design of the overlay topology and the chunk scheduling algorithm. The contribution of the paper is threefold: 1) we propose a realistic simulative model of the system that represents the effects of access bandwidth heterogeneity, latencies, peculiar characteristics of the video, while still guaranteeing good scalability properties; 2) we propose a new latency/bandwidth-aware overlay topology design strategy that improves application layer performance while reducing the underlying transport network stress; 3) we investigate the impact of chunk scheduling algorithms that explicitly exploit properties of encoded video. Results show that our proposal jointly improves the actual Quality of Experience of users and reduces the cost the transport network has to support. I

Effect of oil palm empty fruit bunches (OPEFB) fibers to the compressive strength and water absorption of concrete

Growing popularity based on environmentally-friendly, low cost and lightweight building materials in the construction industry has led to a need to examine how these characteristics can be achieved and at the same time giving the benefit to the environment and maintain the material requirements based on the standards required. Recycling of waste generated from industrial and agricultural activities as measures of building materials is not only a viable solution to the problem of pollution but also to produce an economic design of building