[Halcon vision] image filtering

         The purpose of image filtering is “ Denoise ”. There are three common filtering methods ： Mean filtering , median filtering , Gauss filtering .

One . Mean filtering

         Mean filtering refers to , Pixel value of any point , It's all around N*M The average of pixel values of points .

Two . median filtering

         Average value in the field of use , When realizing denoising , The edges will also become blurred , Therefore, there is median filtering , Around any point ,N*M A little bit , The pixel values of these points , In order from large to small , Median , As the pixel value of the target point .

3、 ... and .  Gauss filtering

         Any point on the image , To the surroundings N*M A little bit , Do a weighted calculation . The point close to the target point , More weight , A point far from the target point , Less weight . The sum of weight values of all points is 1.