The Research Of The Image Collection And Transmission Based On Embedded

The embedded system that is based on computer and integrated circuits and software technology has become the focus of current research and application along with the development of information technique and the popularization of digital product. At the same time, the continuous development of microelectronics technology and embedded operating system has created favorable conditions for implementation of embedded multimedia communication terminals. Mutual integration of Embedded Technology, Network & Communication Technology and Multimedia Technology will become the developing trend of digital video communication field. So capturing and compressing and storing video based on the embedded technique are the ground work of applications about mobile multimedia terminal,and its perspective will be fine and wide.This dissertation aims at developing an H.264-based real-time video communication terminal on an embedded ARMLinux platform. In this dissertation, based on the S3C2440A ARM experimental platform, combining embedded Linux technology and H.264-based video communication technology, a real-time video acquisition and transmission system solution model based on an embedded video server is provided. It provides reference significance and practical value for the actual embedded video communication systems design and development.The author's work include:1.Researeh on real-time video capture technology based on Video4Linux,including USB camera driver development and real-time video capture application design.2.Proposing an application-oriented embedded real-time H.264 video compression coding scheme,and research on multimedia application program optimization methods based on embedded microprocessor architecture. Compile-time optimization and Code-level optimization is applied to open-source encoder x264, to achieve the real-time application requirements.3.The network real-time transmission system and decoding system designing based on RTP. Provide a new video transfer program for the unique characteristic of streaming media data: the sending end make use of RTP protocol to package and transmit real-time through the network; the receiving end unpacks the receive data and realises the reconstruction of a video frame. Finally, PC play it under the linux environment.In this embedded image capture and transmission system, camera acquisition speed can up to 13fps.the encoding speed of x264 can up to about 16.81fps under the average bit rate of 128kbit/s. Although there still has some delay of about 0.5s, but it can meet the real-time requirements of most embedded applications.