scratch or defect (?) detection

hey guys.

i have this photos that i need to find the scratches or defects on them. as an example:

as you can see (i hope you can see) there is a scratch on the upper side of the white band there.

i don't know that much about image processing, but when i surf on this forum, i came to this point:

i used edge detection to find objects on the image, my goal was to determine the objects and eleminate them, hence acquiring an image without any obsticles and only have scratch on it. and then using line detection, or using gradients, find that scratch.

but i couldn't manage to fill in the lines on that BW image. am i doing this hard way? is there a source you guys can forward me to?

any help would be appreciated.

thanks

Answer 1

[Image Analyst]

You need to contact a professional to get your image capture situation fixed. Those are horrible images. If you want to find scratches in there, you need to fix your lighting problems, focus problems, resolution problems, and geometry problems. Once that's done you can start doing the image analysis. But with your current setup, there's little hope to find faint scratches anywhere.

[emre parlak]

hello.

when i do edge detection with canny, the BW becomes like this:

you kida like see the scratch here, so i thought, maybe there is a way to solve this problem

[Image Analyst]

There is too much other clutter in the image. Plus there is a lot of noise and non-uniform illumination. You can either spend a week getting a better image capture setup, or you can spend months attempting to fix crummy images. Plus you should never save your images as JPEG format if you're going to do image analysis on them. Use some lossless compression method like PNG, which is pretty much the defacto standard these days. Is there some reason why you can't or won't fix your bad image capture setup?

Then, if your camera is fixed in a permanent location, which it should be, you can use a template to define the ROI and exclude things like bolts and rails and other clutter. Then you can try some things like thresholding or edge detectors.

[zaydon latif]

Hi Image Analyst sir ... I have a full program for mtatlab for encrypting the image with the Logistic system. I want to change the system from Logistic to Lorenz. Thank you. my email is :

[e-mail]

[zaydon latif]

Image Analyst sir , Do you have an email to talk to you? I want to help you .

[Image Analyst]

No, sorry. I don't need help. Like I said, it's you who should seek the help of a professional computer vision expert to help you design an optical system to capture good images. What you have now is junk. I do this all the time (I have a Ph.D. in optics) but you should probably get someone at an industrial machine vision or scientific imaging company in your own city to help you.