Key Technology Of Real-Time Video Transmission For Mobile Terminals

With the continuous development of intelligent terminal and large area of the wireless network coverage, Mobile terminal user have more efficient data transmission speed and better user experience. Therefore, video application becomes popular gradually. And the technology of real-time video transmission for Mobile terminal is an important part of video application, which can be widely used in many scenes with real-time and flexibility, such as city early warning, scene evidence obtaining and other occasions. However, because of the complex of the wireless network, the efficiency and quality of real-time video transmission of Mobile terminal suffered a huge impact. In order to solve the problems that above-mentioned, the major research work contents of this paper are as follows:The technology of Mobile terminal at present still cannot solve the problem of controlling the rate of data transmission completely. In this paper, the improved congestion control algorithms is proposed, and realize it for controlling the transmission rate of Mobile terminal by adding the ratio of pocket loss rate and threshold, thereby establishing the relationship between rate controlling and entire time series. Experiments show that the method can restrain the negative factors such as packet loss rate, and make the rate rise stable and falling rapidly when the state of network under load or congestion. In the process of video data encapsulation and transmission, this paper based on RTP/RTCP transport and control protocol, using three kinds of combine ways for the data package encapsulation. The key of the combine way is combination the packet of adjacent parameter type in the polymerization encapsulation mode, which can improve the transmission efficiency and reduce the risk of data loss. In addition, this paper testing the main power-consuming parameter when the Mobile terminal in the process of transmission video. And find the proportion between the parameter within a certain range, which is a great reference value for Mobile terminal saving power.Based on the theoretical research, this paper design and implement the video real-time transmission software based on the Mobile terminal and realization the system of video real-time transmission for Mobile terminal which including server-side, client-side and cloud storage-side. The system utilize several ordinary PC machine to build the hadoop cloud platform and storage a large number of video of the client through the distributed file storage system.