星载拼接相机图像实时校正系统的研究

为了实时对多TDI-CCD拼接后获得准确与高质量的大视场图像,建立了多片TDI-CCD拼接相机像元实时校正系统.对该系统的图像拼接与灰度融合算法进行研究并对硬件实现方法加以介绍.对多片TDICCD拼接技术以及由此带来的图像错位与像元不均匀性进行了介绍,采用输出缓存技术实现拼接TDI-CCD奇偶片输出图像配准,应用比值平均法校正拼接片间的灰度不均匀性,实现实时大视场拼接校正.并将整套算法在Xilinx公司的Spartan 3系列的FPGA平台上实现,得以构成多TDI-CCD拼接校正系统.实验结果表明,该系统可以自动对3片2048像元的TDI-CCD拼接配准与灰度校正,获得清晰的大视场图像,满足系统实时性的要求.

Study on Real-time Correction System of Spaceborne Mosaic Camera

In order to obtain accurate and high-quality images after multi-CCD mosaic, a real-time multi-CCD mo-saic and correction system was established. Algorithms such as image mosaic and grey correction and the hardware implementation method were described. The technology of multi-CCD mosaic, the mistakes and the non-uniformity of multi-CCD mosaic were introduced. The image matching was realized by output buffer technology, the gray non-uniformity of mosaic chips was corrected by ratio average method. A multi-TDI-CCD image mosaic correction system based on Xilinx Spartan 3 series FPGA was developed and the whole algorithm was implemented in this system.The test results showed that the system could automatically mosaic three TDI-CCD chip images of 2048 pixels and met the real-time demand.