The Design And Realization Of Embedded Image Capture System Based On USB

At present, the study of image acquisition system focused mainly on the PC-based image acquisition. Such systems have limitations. The main defects is the poor portability, it is extremelly diffcult in some situations. There are more and more developing based on embedded systems in the needs of applications and the promoting of the IT technology.The aim of the thesis is to develop an Image Acquisition System based on the embedded systems.In this paper, we develop a image information processing terminal based on Intel's xscale processor PXA250 provided basic network function, considering the characteristics and reality of the embedded system application needs. Take the PXA250 as the core, transform the image information collected by the USB camera to the memory through the ISP1161 USB host controller assembled on the board, and then transform the image to the remote PC through network interface, realize the image acquisition, and network transmission.In this paper, mainly studies the design of the image capture module based on embedded system from two respects of software and hardware. The research of systematic hardware controlling platform mainly includes:the architecture of ARM and PXA250 microprocessor, the structure and function of USB controller ISP1161,and the application requirements of Sistang development board; The research of systematic software operation platform mainly includes:the knowledge of USB protocol, the working mechanism of Linux operating system, the design of USB driver in Linux environment, the implement of video capture, and realization of the network transmitted etc. The embedded operating system chooses for Linux, and has design system. The paper has introduced the establish of cross-compiler environment, the transplantation of embedded system leading procedure Redboot, the transplantation of Linux kernel, the Jffs2 file systems, and major relevant technology used during embedded system development. Finally, give the results of system debugging.The experiment results shows that, the developed system has the stability in data transmission and the high reliability, can fulfill the basic demands.It has been transplanted with the embedded operating system, easy for the follow-up developing to add new functions the user needed.The system has a broad future.