Design And Implementation Of Real-time Video Transmission System Based On WebRTC

With the development of modern information technology,Unmanned Aerial Vehicle(UAV)technology has become more and more mature,which has been widely used in industry,agriculture and national defense.As an important part of UAV technology,video-transmission system can capture video and send it to the receiving terminal for displaying in real time.However,the receiving and playing of video data must use the dedicated devices in traditional video transmission systems.In addition to the high cost of data receiving,it is difficult to achieve multiple user receiving video data simultaneously.Therefore,it is of great significance to design a video transmission system without specific receiving devices,and this system can receive video data on different platforms.WebRTC,an emerging real-time communication technology,can bring the real-time transmission function of audio and video media data into the browser.In order to solve the limitations of traditional video transmission system,this paper designs a video transmission system which can receive and play video without specific receiving device through browser based on WebRTC technology.The design of this paper is divided into two parts:video capture device and server module.Video capture device is used as the airborne device of UAV for video capturing.To relieve the data transmission pressure,the video capture device encodes the original video data with H.265 encoding to reduce the bitstream size.Hisilicon HI3516 video processing chip is used in the encoding of H.265,and the effect of the video bitstream on the network is decreased by the refresh in P frame.After the video encoding,video capture devices sends the bitstream data through the 4G mobile network,so the transmission distance can be farther than the traditional video-transmission method.On the server side,the transmission of video data from server to receiver is realized in terms of the WebRTC technology.In order to ensure the stability and reliability of the video data transmission process,the server side uses Kurento to adapt the video bitstream,which is suitable for transmission under different network environments.Then,the server side on basis of the Spring boot framework is built,and the users can receive and play the video by accessing the page through the browser without any special equipment.The paper designs a series of tests for the system.The testing results show that the H.265 encoding performance of the video capture device is excellent and the power consumption of the device is lower than 3W.The WebRTC video transmission function has been tested with excellent results,the video data can be received and played through Chrome,Firefox and Safari browsers which run on Windows,MacOS,Ubuntu and Android,and the video bitstream can be adjusted according to network conditions during transmission.The performance of the real scene is tested by using of the UAV to carry video capture device.The results show that the mainstream browsers can receive stable video when the flying distance is within 50 meters,and the video occasionally fluctuates when the flying distance is 100 meters.Finally,the load of the system is tested.The testing results show that the load of the system which can support more load than the traditional graph at the same time,it is mainly related to the bandwidth of the server.It is proved that the system has excellent performance and is of great use value through these tests on this system.