基于FPGA的红外序列图像中热晕背景的消除

红外探测器在工作时间长或太阳直射时，可观察到红外图像有热晕现象。红外探测器观察的景物亮度或对比度通常很低，此时热晕对红外像质的影响比较严重。针对上述情况，研究用数字图像处理的方法——帧相减、反色相加，对红外图像进行实时背景补偿，以便消除热晕的影响。根据该方法进行了硬件设计，并且在现场可编程门阵列(FPGA)中实时实现了。实验结果表明，该方法能够在硬件平台上对红外图像热晕背景进行实时补偿，可明显改善图像的质量。

Elimination of Thermal Halo Background in Infrared Image Sequences by FPGA

When an IR CCD (Infrared Charge Coupled Device) is directly illuminated by the sun or works for a long time, the thermal halo background in the infrared image sequences can be observed. The luminance and contrast of the image obtained by the IR CCD are generally low, so the influence of the thermal halo background on the IR image is serious. In order to eliminate the influence of the thermal halo, a method of real-time IR image background compensation by using the digital image processing means - subtraction, reversed addition is submitted. Then, a hardware designed on the basis of those methods is used to implement in the FPGA (field programmable gate array) in real time. The experimental result has indicated that the image's quality can be improved by the thermal halo background compensation.