how to do edge detection of image for comparison?

i am trying to compare different images of same object. i want to do edge detection but i didn't get the edge detected perfectly. how it can be done?

[KALYAN ACHARJYA]

There are various types of Edge Detection Techniques, It depends on your application image. Follow Link here Please share your input image, so that user can help you easily. Please clarify..In comparison with which image?

[amala]

i am doing canny edge detection. but when different are used to compare the threshold value changes for each image. how can i set the algorithm for canny to detect edges at different thresholds???

Answer 1

[Image Analyst]

There may be no "perfect" edge. And there are lots of possible/alternative edge images that could be generated. The edge image you get that can work for you is the one that you should use.

[amala]

is it possible to bring all the images (to compare) into single pixel?

[Image Analyst]

What does that mean? Do you mean like you want edges skeletonized? Or you want some figure of merit that is a single number to characterize the "goodness" of the edge?

[amala]

i need a single line diagram by doing edge detection.

[Image Analyst]

You can use edge() to get single pixel wide edges.

binaryImage = edge(grayImage);

You can use

binaryImage = bwmorph(binaryImage, 'skel', inf);

to skeletonize any binary image (if it's not already down to one pixel wide of course).