How to detect circles in the given image?

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Anannya Uberoi
Anannya Uberoi am 17 Mai 2017
Kommentiert: Image Analyst am 1 Apr. 2018
I am working on a series of images- some blurry, some sharp. My aim is to detect the outer boundary of the iris.
After adaptive thresholding, the image becomes:
I have applied similar adaptive thresholding to all my test images- some of them are blurry, some have sharp focus measures. A few of my results:
I want to extract the circular boundary which marks the iris through a common code. Although it is quite visible intuitively, neither of regionprops or imfindcircles is able to locate the iris. Moreover, in some cases, it is not exactly a complete circle, and gets trimmed across the left and right edges while capturing the photo.
Any help or advice on this would be much appreciated!
  1 Kommentar
Swarooph am 17 Mai 2017
More pre-processing could help. Try performing some morphological operations to reduce the noise (non-circular features) in the image before using imfindcircles. Some documentation to help:

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Antworten (2)

Image Analyst
Image Analyst am 17 Mai 2017
There are so many iris detection algorithms. Just check the literature for the latest and greatest one(s):,%20Detection,%20Tracking,%20Gesture%20Recognition,%20Fingerprints,%20Biometrics
21.5.3 Biometrics, Iris Recognition Systems Iris Based Biometrics, Biometrics Engineering Research Center, Dongguk University Iris Recognition Systems, Infrared, Near-Infrared, NIR Based Iris Recognition Systems, Wavelet Based Iris Detection, Segmentation and Localization Systems Iris Recognition Systems, Systems, Evaluation, Comparison, Surveys
  3 Kommentare
pawarcse am 24 Mai 2017
Hello, I am currently working on Iris Recognition and I am having problem in detection of pupil and sclera Boundary. Please help me to solve this problem!! I am using Daugaman Algorithm.

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shivu shetty
shivu shetty am 1 Apr. 2018
hellow can i get that code plz .i need to count rings in this image .help me
  1 Kommentar
Image Analyst
Image Analyst am 1 Apr. 2018
Contact the Laboratory of Tree Ring Research at the University of Arizona. They started the field and are probably still the world's leader. They can probably point you to their best publications. You might even be able to obtain code from them.

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