Adaptive Multimedia Transcoding for WWW Content Delivery

Abstract

The explosive growth of the network, end-host performances and their heterogeneities have resulted ever changing advancement and complexity of distributed computing environments. The users in such environment have not been provided a satisfactory service when they access the required objects. In this paper we focus on adaptive WWW content delivery, which is the most ubiquitous and popular way of information dissemination, primarily in the form of web-server, web-browser interaction. In these applications, we address controlling the Quality of delivery and time of access tradeoff of the WWW contents. We implement this as a httpa protocol, which is an adaptive transcoding methodology for embedded images in web pages, according to available channel bandwidth and other accessibility parameters at the client side. Compared to the conventional form of server side adaptive content delivery proposed in the literature, we propose a hybrid form of adaptation: client side progressive parameter estimation and server side transcoding of images, which is more scalable and flexible. Through experimental results we verify the performance of httpa. I INTRODUCTIONThe explosive growth of the network, hardware and software technologies have opened the way to advanced and complex distributed computing environments. With the inherent heterogeneities in network links, end-host performance, and client preference the clients are receiving varying quality of the data objects, but having little or less relevance to client's requirements. Here, the Quality of the data objects is considered as the timely access of high consistent objects. We discussed these issues in [1], [2] with the dynamic changes of the environment information (underlying network and end-hosts performances). Moreover, we provided a set of access strategies for the clients to dynamically select the optimal strategy according the environment information changes. To efficiently detect the network and end-host performances and subsequently to change the optimal access strategy, we used the middleware object called Reconfigurable Object [3]. In our previous works we mainly considered the client-side adaptation by changing the access semantics of the server object according to the environment information.Here, in this work we consider adaptation of contents by hybrid form of processing done at both client side and server-side. The server performs the dynamic changing of the quality and/or diminutions of objects whereas client detects the operating conditions of the environment (available network channel bandwidth and client's performances).Today, with the phenomenal growth of the Internet, the World Wide Web (WWW) has become the most ubiquitous and the most popular way of information dissemination, primarily in the form of web-server, web-browser interaction. However, with the inherent heterogeneities in network links, it has not been able to provide a satisfactory service to the whole set of WWW user population. Moreover, the variability of the client (i.e. high-end client ma...