上述方法能使图像反差增大，同时反映出缺陷点和正常点的不同时刻信号值的不同变化，并以此作为判断被检件是否存在缺陷的依据。

Those methods could enlarge the contrast of image and indicate the different change between the defect and the normal signals at different time. And it could be the basis to judge if there was defect.

youdao

上述方法能使图像反差增大，同时反映出缺陷点和正常点的不同时刻信号值的不同变化，并以此作为判断被检件是否存在缺陷的依据。

Those methods could enlarge the contrast of image and indicate the different change between the defect and the normal signals at different time. And it could be the basis to judge if there was defect.

youdao