Design Of Video Capture And Network Transmission Module Based On DSP

The high-speed data processing ability of DSP makes it widely used in such aspects as sound, image, code, digital device, communication system, medical treatment system, aviation. Especially in the aspects of compressing and encoding of image, the combination of DSP technology and Internet technology make the image transmission more and more easier throughout Internet. And transmitting efficiency can be improved within the limited network bandwidth by using telecommunication technology reasonably.Therefore, systems based on DSP may have more extensive application in the fields such as security surveillance, long-distance medical treatment etc.According to the traditional Web-Camera based on PC whose stability is bad, efficiency is low as well as the system structure is complicated and so on questions, This paper presents a high speed Web-Camera's design proposal based on the DM642. Through the research of the streaming media protocol, the hardware and software design of high speed Web-Camera based on DM642, the integration of video capture, video signal processing, network real-time transmission and process control are realized. The result shows that using DM642 which is the special video processing chip can improve the whole Web-Camera's efficiency and performance greatly, also it can solve the contradiction between transmission rate and image quality well and be easy to update.The paper has demonstrated the design of every module of the Web-Camera, especially image gathering, network transmitting and program design. Discuss rate allocation and bandwidth estimation which are two main factors in streaming media transmission algorithm, and decide to transmit streaming media throughout controlling TCP/IP transmission protocol and using different transmission typies in different transmission duties. Meanwhile realize video data's presentation in client by designing application program with network communication function. Finally, the paper makes a basic function test and summary about the system. The paper also proposes the imagination and route of perfecting and improving further.