中波红外相机盲元的实时动态检测与补偿方法

Real-time Dynamic Blind Pixel Detection and Compensation Method for Mid-wave Infrared Camera

盲元的存在严重影响了红外相机的成像质量,基于场景的盲元检测与补偿方法可以有效地解决此类问题。本文提出了一种改进的局部"3σ"方法,通过计算图像的三维噪声获得图像的平均噪声,据此得到盲元检测的最小判据,然后采用局部"3σ"方法和中值滤波法对盲元进行实时的动态检测与补偿,并将该方法应用于自研的某中波红外相机中。对黑体成像实验的结果表明,本文方法与辐射定标法相比,盲元检出的重合度平均可以达到82%以上;与传统的局部"3σ"方法相比具有相同的盲元检测与补偿效果,但可以将盲元的过检率降低30%以上;地面及载机挂飞成像实验的结果表明,本文方法可以对盲元起到很好地抑制作用,红外相机的昼间和夜间图像均不存在明显异常的黑、白点,图像中景物细节丰富、图像质量优良。因此,本文方法可以对盲元进行实时的动态检测与补偿,在自研的中波红外相机中的运用是可行和有效的。

The existence of blind pixels significantly affects the imaging quality of infrared cameras.Scene-based methods for blind pixel detection and compensation can effectively solve such problems.This study proposes an improved local"3σ"method.The average noise of the infrared image is obtained by calculating the three-dimensional noise of the image;according to this average noise,the minimum criterion for blind pixel detection is obtained.Subsequently,real-time dynamic detection and compensation for blind pixel is performed by local"3σ"and median filtering method;furthermore,the method was applied to a self-developed mid-wave infrared camera.The results of the blackbody imaging experiment show that,compared with the radiation calibration method,the coincidence degree of blind pixel detection of our method can exceed 82%on average.The proposed method has the same effect of detection and compensation for blind pixel compared with the traditional local"3σ"method;however,it can reduce the over-detection rate of blind pixel by more than 30%.The results of imaging experiments of ground scene show that the proposed method can effectively restrain the blind pixel,and no apparent abnormal black and white spots were found in both daytime and nighttime images captured by the infrared camera.Additionally,the scene details in the images are rich,and the image quality is excellent.Therefore,the method presented in this study has good performance in real-time dynamic blind pixel detection and compensation.It is feasible and effective for use in self-developed mid-wave infrared cameras.