MATLAB: How to detect defect in finish product

Question

I want to detect defect in finish product such as washing machine. There are many knobs available on machine. I want to detect is there all knobs present or not ? i.e. detect missing component of machine front panel. You can also view some images of washing machine on: http://www.edaboard.com/thread241472.html#post1033219

Answer 1

Your link doesn't work. I'd just take a photo with stable, controlled lighting with a camera at a fixed position and subtract the image from a known "perfect" image. Do a little clean up (noise removal, hole filling, etc.) and count and locate the blobs that are present in the subtracted images. Actually this is pretty easy. You can post the "perfect" image and the "missing component" images on tinypic.com if you want.