Research And Implementation Of A Video Sharing System On Smartphones

With the 3G/4G networks widely deployed and enhanced globally,the mobile network can support more diverse types of services. But the growing number of users, as well as the increasing amount of data traffic also makes the existing 3G/4G networks gradually overwhelmed. The widespread popularity of smartphones and increasingly powerful features of them accelerate the user’s demand for 3G/4G networks,especially for high-definition video services, which contribute a major part of the mobile video traffic and are predicted to have a greater increase and the share ratio in the future. Although 4G significantly increases the cellular throughput and the peak rate, yet the frequency resources are still scarce limited. How to use the limited frequency resources to meet the growing demand for video services has become an important bottleneck to the user experience.Mobile video services have a certain user clustering. In some crowded places, such as the subway stations, users tend to watch videos in the waiting process. Due to the closure of these places, large user density and other reasons, the coverage and access experience of 3G/4G networks will be weakened, resulting in contradiction between supply and demand. For this kind of problem, this thesis designs and proposes a kind of live-video sharing system based on Android smartphones. The video sharing system allows users that are geographically close to each other to download video data individually via the cellular network and perform data sharing simultaneously via the WiFi-Adhoc based broadcasting network.This system has the following characteristics: first of all it works as a middleware, and thus can cooperate with third party video players. In addition, it supports members in dynamically joining or leaving an existing sharing group. Finally, it treats group members equally. There are no role differences and the division of different responsibilities among the members of the group. Users needn’t consult with each other during the operation procedure. The above characteristics are the main innovation points of this thesis. The performance evaluation results show that compared with the traditional video streaming method, the sharing system proposed in this thesis reduced the cellular network traffic consumption. The degree of reducing is in relation to the number of devices within a sharing group. What’s more,the system reduced the halt phenomenon caused by the depletion of video buffer, and reduced around 15% of the energy consumption on smartphones. So the system can reduce the pressure of data transmission in cellular networks and provide better user experiences.