大面阵CCD航测相机图像去黑斑的处理

Processing of the Black Speckle in Digital Image of Large CCD Camera

在大面阵数字航测相机的使用过程中,存在影像光照不均匀的问题。由于硬件设计很难达到预想的效果,在光照过于强烈的情况下,还会产生CCD过饱和的现象,通过增加遮光片可以解决这一问题,但全色波段的影像会产生黑斑。而通过马斯克匀光的方法去除中心的黑斑,提高影像的质量,并且将图像中心的反差增大,加大对比度,增大图像灰度的动态范围。

When we get images from Digital Large Color CCD Camera, there exist a problem that the illumination is uneven. For the limitation of the hardware design, the CCD may supersaturate under strong light. This problem can be solved by adding a piece of shade, but then there will appear black speckles in the center of panchromatic image. With the method of MASK dodging, the black speckle can be removed and the quality of the images will be improved. This method will also increase the contrast of the center of the image, thereby expanding the dynamic range of the grey scale of the image.