高分辨率CCD数据合成系统的设计

Design of high resolution CCD image data combination system

为充分利用航测拍摄间隔的非工作状态时间,本文设计了一个应用于航空摄影测量的大面阵CCD数字相机合成系统。该系统将3路高速CCD相机数据同步后,通过在FPGA内设计SDRAM读写模块和SDRAM控制器,以SDRAM作为高速缓存,并构造图像数据合成单元,实现将多路高速CCD相机图像数据合成为一路数据输出。整个系统时序逻辑控制均在FPGA中完成,改变了传统一套记录单元对应一路相机记录的模式,实现了用一套记录系统同时对3路高速CCD图像的实时记录。在实际航测拍摄间隔大于4s的情况下,仅在约633ms时间内完成了图像合成和实时记录,大大提高了记录系统的效率,降低了系统功耗。

In order o take full advantage of aerial shooting of non-working state time interval, a kind of data combination system of high-resolution digital camera used for aerophotogrammetry was designed in the paper. After synchronization of three-channel high- speed CCD camera data, SDRAM as a mass storage body, through design of SDRAM reading/writing modules and SDRAM controller in FPGA, high speed CCD image data from multiple channels were combined to one output in sequences, thus the imaging data from mul- tiple CCD cameras could be recorded by only one recording system. In case of short interval more than four seconds, image combination and real-time recording were completed in less than one second. The efficiency of the recording system could be improved and system power consumption be reduced.