Since you appear to be completely "out of track", I'll try to point you in a better direction. The starting point is your statement that a "lake" is a specific pigment spot. Accordingly your question reduces to a problem of color recognition.
What I would do is :
1/ Find the color spectrum of the whole iris, excluding the white surrounding region and the black central pupil. For that you should first create programmatically the corresponding annular ROI (ROI-1), and then use IMAQ color learn.vi.
2/ Define a small circular ROI (ROI-2) that will be used as a probe. Chose a circle diameter corresponding to the size of the lakes to be spoted.
3/ Move this probe in a loop over the entire ROI-1 and see, for each position if there is a color matching, using IMAQ ColorMatch.vi. You'll have to define the required minimum match score by successive trials until you reach a satisfactory result. I would use 600 as starting value.
That way, variations of the ROI-2 color relatively to the average iris color would be detected, giving you the position of the "lakes".
This, of course, is *much* different from your proposal, and you'll have a significant amount of work to do, that can't be achieved in NI Vision assistant, altought some prototyping can be done with rectangular ROIs. Well, image analysis is not for the faint-of-heart, and the sooner you'll realize that, the better ! 😉
And again, if you where able to better define what a lake is, and show somebody how to locate the lakes, other strategies, may be simpler to implement, could be defined. Yours is truely a dead end...
Message Edité par chilly charly le 10-31-2007 03:36 AM
Chilly Charly (aka CC)
