LabVIEW

cancel
Showing results for 
Search instead for 
Did you mean: 

vision local threshold sauvola selects weird sections of background

 Hi, I'm trying to use the local thresholding feature. For my particular image, niblack doesn't work that well but the sauvola and modified do -- except that it selects a huge swath of the background. Not the whole background, though, which is odd. 

 

The image itself is obviously made up but is a representation of what I want to select (the triangles). The raw image is at the bottom. Any ideas on why its selectively picking a column of background out of the image? Any ideas on how to remove that section?

 

Capture.PNG

 

 

For comparison, in this simplified image Niblack works fine. I basically want the goodness of the sauvola without the weirdness.

c2.PNG

 

 

 

 

Untitled.png

0 Kudos
Message 1 of 4
(2,309 Views)

Hello there!

 

I think you could use another function once you get your binary image from that to get rid of the big perimeter area. It is called "Particle filter", it is on the "Binary" processing functions tab.

 

Here is a screenshot of what I did:

 

solved.PNG

0 Kudos
Message 2 of 4
(2,269 Views)

Ah yes, you're right. Thats seems like a reasonable way to get rid of that ring. Thanks.

0 Kudos
Message 3 of 4
(2,260 Views)

You are very welcome! please consider marking this post as solved, as your question has been addressed.

0 Kudos
Message 4 of 4
(2,247 Views)