New video discarding policies for improving UDP performance over wired/wireless networks

Abstract

SUMMARYMultimedia communication over wired and wireless networks becomes a compulsory need for many recent applications. To effectively react to the tremendous demand of video streaming over the Internet, videos are usually compressed by utilizing spatial and temporal redundancy. It is noteworthy to mention that compressing videos may degrade their quality if it is not investigated properly. In other words, as a consequence of exploiting redundancies, frame dependencies emanate, which make discarding frames, because of occupying the whole capacity of network elements, have severe implications on the video quality. Furthermore, transmitting videos over capacity-limited links owing to error-prone channels, power constraints and bandwidth variations will severely affect the video quality. Additionally, as the current coding schemes are characterized by being able to afford high compression efficiency, sensitivity to packet losses becomes untolerated. Therefore, insuring the perceived quality of the delivered videos to be always high in spite of aforementioned challenges is the primary focus of current researchers. In this paper, we propose efficient and novel video discarding policies that mainly aim to reduce the number of frames being lost through substitution of those frames that are very difficult or even impossible to decode at the receiver side. This is accomplished by controlling and maintaining the buffer occupancy of network elements. Our proposed policies are evaluated in terms of frameput, rate of non-decodable frames, peak signal-to-noise ratio, structural similarity index and average buffer occupancy. Our proposed policies behave very well and achieve a remarkable enhancement over what is closely connected in the literature.

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