Summary: | 碩士 === 國立臺灣科技大學 === 電子工程系 === 98 === Video streaming quality in a wireless communication network environment is largely affected by various network characteristics, such as a limited channel bandwidth and a variant transmission rate. The playback quality on User Equipments (UEs) may not be smooth when the service is delivered via a wireless environment. From the viewpoints of most video receivers, a smooth playback with a lower video quality may be more significant than a lagged or distorted playback with a higher video quality as the transmission rate degrades. Based on above, we sketch an adaptation agent - Transmission-Rate Adapted Streaming Server (TRASS), which is located between the original video server and UEs, to adaptively transform the streaming video based on the real transmission rate. In our proposed scheme, UEs would feed back their network access statuses to TRASS and then TRASS would deliver adaptive quality of video streams to UEs according to their feedbacks. The theoretical analysis and simulations using different video tracks encoded in MPEG-4 and H.264/AVC formats show that TRASS can help wireless streaming users get a smooth playback quality with a lower packet failure rate. With a low probability of receiving a worse quality of video, users’ Quality of Experience (QoE) can subsequently be raised.
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