| This dissertation is a sub-research problem of laser communication. It is about the solution of video capture of the whole communication system. Based on the comparison of the research work, the paper demonstrates a design of video capture system with a standardized interface. In the design period, it makes the system miniaturization standardization and modularization by using the structure of FPGA+SAA7111A. It uses FPGA as a control, and initializes the A/D chip SAA7111A by sending codes through I~2C bus in order to obtain digital video signal according to the request. To make it easier to read the data of the external image processing cell, it designs two memory cells which are mutex to each other for the storing of odd fields and even fields data separately. And it also designs a standized interface .Besides, in order to minimize the data flux, it reads out the image and preprocesses the image. At the same time, the paper also makes a summary of system design and debug experience, and makes deeply analysis of several problems. Through the repeated test simulation, may prove the entire picture gathering plan is feasible, can be able to apply in the high speed picture gathering processing system. |
