circle detection algorithm?
May 20, 2006 7:19 AM Subscribe
computer vision: i need an algorithm to extract statistics about the diameters (in pixels) of some roughly-circular objects from an image file.
posted by sergeant sandwich to computers & internet (15 answers total) 1 user marked this as a favorite
i have many, many files that are grayscale images of some spherical objects. they are relatively high-contrast and so i should be able to do some kind of easy thresholding and/or edge detection to bring out the edges. but what i need to do is parameterize the circles - i need a count of circles in each picture, and a measurement of each circle's radius so that i can get an idea of the size distribution.
i understand that the hough transform
can be used to parameterize lines and circles, but for the circles you need to know the expected radius beforehand. i could brute-force it and simply feed in a range of expected radii and have it step through each one, but that's both computationally demanding and i am particularly interested in the outliers, which this method might miss.
can anyone point me to an algorithm that might do what i'm looking for? is such a thing in the machine vision canon? it's been a long time since i took this course. thanks, askme!