Trouble Removing Uneven Background Lighting from Image

Question

Nathan 2015-5-20

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/217791-trouble-removing-uneven-background-lighting-from-image

评论： Jeff E 2015-5-21

Hello,

As I stated I am having some trouble removing a background from an image. I have tried using imopen, imtophat, and a couple other methods, but all of them result in the same problem. The code considers my entire image as a background. For example, here is my original image.

My code to load it is pretty simple

drop=mat2gray(imread('st000.tif'));

As you can see the illumination is fairly uneven, and when I go to convert it to a bw image it cuts off the last half of the stream. When I try and use imopen to find the background this is what I get.

 background = imopen(drop,strel('disk',15));
 figure()
 imshow(background)

If I use imtophat I get this.

I2 = imtophat(drop,strel('disk',15));
figure()
imshow(I2)

Since this image is a little dark, I tried to enhance it using

I3=imadjust(I2);
figure()
imshow(I3)

which gave me

I can't really use this image, since it is so blurry. I have tried taking a static image with the background, subtracting that from the bw image of the original, and that sort of works.

But as you can see it removed a lot of the resolution on the image, which I think has something to do with how I actually convert it into a bw image. I think I can get a better resolution if I can find a way to make a uniform background before converting it to bw.