Analysis of the image quality transmitted by an IPTV system

Abstract

This article compares the results obtained when evaluating the PSNR (Peak Signal-to-Noise Ratio) metric when television and video content is delivered on demand on an IPTV-IMS platform using the RTSP and HTTP protocols. Several scenarios are evaluated for this. Initially, television is broadcast using the RTSP protocol, switching between wireless and wired networks and varying the network load. Later this process is repeated for the HTTP protocol and finally video is broadcast on demand repeating the load conditions and network type. Each of these scenarios starts with a user receiving the transmission and ends when 10 users are connected. The results of these tests are plotted and compared in order to determine the quality of the image received in the different scenarios implemented. Keyword-Real Time Streaming Protocol (RTSP), Hypertext Transfer Protocol (HTTP), PSNR, MSE, IPTV-IMS I. INTRODUCTION At present, one of the most demanding transmission flows in terms of resources in communications networks is related to the delivery of multimedia content (television and video on demand over IP). It is therefore important to investigate, study and evaluate the level of quality with which the signals or images reach the receivers or end users. For this reason, this article presents the results found when evaluating the PSNR metric in order to determine the relationship between the maximum energy of a signal (image) versus background noise; and for this the present article is divided into three large Sections that includes the design of the IPTV platform on which the tests were carried out, to subsequently share the results found and the final conclusions. II. IPTV PLATFORM DESIGN. For the implementation of an IPTV platform, there must be a minimum of entities that guarantee the correct functioning of the platform. Initially, an IMS core must be available, which was implemented in software through the Open IMS Core [1] and which includes three call session control entities (CSCF) and a user database. However, three more elements are required, which are what will ultimately shape the implementation of an IPTV system. These elements correspond to the IPTV application server (IPTV AS), the IMS Client and the Media Server. The first two as well as the core have been developed in free code by the Communications Research Group of the University of Cape Town [2] in South Africa. The IPTV application server developed under the name of UCT IPTV Advanced allows loading the address table in which the search of the selected contents will be carried out. Regarding the IMS client, there are several free code options available to work with the selected project, which have different characteristics [2]. However, the only one that supports IPTV is the UCT IMS Client, which has a simple interface in which there are several options such as client registration, preference settings, different call options, video call, instant messaging and request of channels or videos available. However, this client is only available for computers, so if ...