# Machine Vision

Showing results for
Did you mean:

Solved!

# colour to grey scale and crack detection

how to convert a colour image to grey scale. also i want to know how to detect the cracks in the objects from their images
Message 1 of 15 (2,426 Views)
Solution
Accepted by topic author saillesh
‎08-27-2015 06:09 PM

## Re: colour to grey scale and crack detection

There are 3 planes involved in a color image. Each plane having values 0-255. By extracting any single plane you can convert the image to a grey scale one.

Try extracting the luminance plane (in color plane extraction).

Use vision assistant initially to get an idea.....

Message 2 of 15 (2,414 Views)

## Re: colour to grey scale and crack detection

how to detect the cracks in the objects from their images

If the crack in really nicely different from the object then applying a proper threshold and removing small particles and going with a particle analysis will be enough.

But we need details.If you can post some images then I can suggest you a method

Message 3 of 15 (2,414 Views)

## Re: colour to grey scale and crack detection

Message 4 of 15 (2,408 Views)

## Re: colour to grey scale and crack detection

Saillesh,

What muks suggested is a very practical approach. I personally implemented it with object filtering to detect cracks in an online ceramic plates inspection.

Waleed El-Badry MSc.,MCPD, ISTQB Certified Tester
Assistant Lecturer
Mechatronics Department
Faculty of Engineering
Misr University for Science & Technology

Message 5 of 15 (2,406 Views)

## Re: colour to grey scale and crack detection

[ Edited ]

to convert a color image to gray scale you can average all three planes or you use different weights for the color planes. Typical weights are

30% red + 59% green + 11% blue

Message Edited by Jörn on 2009-08-12 12.08.2009 11:48 PM
Message 6 of 15 (2,393 Views)

## Re: colour to grey scale and crack detection

i wan to detect the cracks in tracks of train .can i use fft for this . if any other soluion please help me
Message 7 of 15 (2,332 Views)

## Re: colour to grey scale and crack detection

i have to inspect cracks in the train  tracks . is your method of object filtering is suitable for that ?.
Message 8 of 15 (2,331 Views)

## Re: colour to grey scale and crack detection

Well posting a few sample images will do a lot of help. I mean there is no other way  we can suggest algorithms to use. We can only keep guessing.
Message 9 of 15 (2,329 Views)

## Re: colour to grey scale and crack detection

im posting my pictures here  (with and without cracks),could u help me with the algorithms.i have taken fft for this, is there any option to get the strength of fft to compare the images?

Message 10 of 15 (2,271 Views)