闪光照相CCD图像的自适应中值滤波方法

Adaptive Median Filter for Flash X-Ray Radiographic CCD Image

中值滤波是一种在去除噪声的同时能较好地保护图像边缘细节的非线性图像处理方法。为了滤除闪光照相CCD图像中的脉冲噪声,同时能更好地保护图像边缘,提出了一种改进的自适应中值滤波方法。该方法采用局部中值和局部方差作为判断噪声点的阈值,实现了局部自适应的中值滤波,克服了传统自适应中值滤波方法的缺点,对椒盐噪声和随机脉冲噪声均有较好的滤波效果。实验结果表明,该方法消除图像脉冲噪声十分有效,对闪光照相CCD图像的处理结果也较好。

Median filtering is a non-linear image processing method that can preserve image edge while removing noise. In order to preserve image edge more efficiently while removing the impulse noise in flash X-ray radiographic CCD image, an improved adaptive median filter method is proposed in this paper to avoid the shortcoming of the traditional adaptive median filter. The new method takes the local variation and local median value into account. So, it is a local adaptive median filter. It can get better filtered result not only for salt-pepper noise but also for random impulse noise. The experimental results show that the new method is very efficient to remove the impulse noise. It also can get better result for flash X-ray radiographic CCD image.