Measure pupil size in image of eyes

I've been trying to find a way to measure the size of a pupil in a close-up image of an eye. I want to turn this into an Android app. I have previous Android experience but can't find any Java solutions to the problem itself.

There is lots of example code for face detection and even eye detection but none that will examine a still image and find the pupils, t开发者_开发知识库hen measure them. Does anybody know how I could proceed in trying to measure the size of the pupil?

Thanks,

Mark

This is an extremely difficult question. Using computer vision algorithms you can isolate the pupil and measure an average diameter in pixels, but you would ever be able to translate that into physical size without knowing how far the eye is from the camera and the camera's field of view. For example, you could have a person with the camera a few inches from their eye and their pupil could be the same size in pixels as a picture of an eye on a billboard 100 feet away. Even though, physically, they have very different sizes.

It seems like Android OpenCV would work for your needs. Good luck getting it all to work.

http://opencv.willowgarage.com/wiki/Android2.2