TDICCD拼接相机的像元响应非均匀性校正方法

Correction of pixel response non-uniformity in TDICCD mosaic camera

为了解决光学TDICCD成像系统在拼接模式下的像元响应非均匀性问题,研究了TDICCD像元校正的原理和实现方法。提出了视频处理器在不同增益、不同偏置和TDICCD在不同积分时间下进行像元校正的方法,设计了在现场可编程门阵列(FPGA)平台下进行了程序实现和验证的方法。实验数据分析表明:成像系统单片TDICCD的非均匀性由4.72%降低到0.27%,恶劣环境下TDICCD成像系统的图像非均匀性可以降低2.55%。该像元级校正算法简单,可靠性高,能够满足星上成像的要求;在不同的增益、偏置和积分时间下能够很好地解决TDICCD成像系统的像元响应非均匀性问题。

To improve the Pixel Response Non-uniformity（PRNU） in a TDICCD mosaic camera, an algorithm was proposed to correct the PRNU between the channels and among the pixels in channels at different gains, deviations and integrated time. Then, a design method was given to implement the algorithm on a Field Pro- grammable Gate Array（FPGA） platform. The experimental results indicate that the problems of PRNU could be solved at different gains, deviations and int gle TDICCD could be decreased from 4. 72% egrated time in the TDICCD mosaic camera. The PRNU of a sin- to 0. 27%. In bad circumstance, the PRNU of the single TDIC-CD could be decreased from 4.68% to 2. 13%. The actual image also proves that the pixel correction algo- rithm has high real time performance, high reliability and stability, and a satisfied result to the requirements of space-projects. It solves the real-time pixel correction problem of the PRNU in TDICCD mosaic cameras.