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boy boy

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Nov 24, 2009, 12:01:19 PM11/24/09
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Image: http://salmaworld.files.wordpress.com/2009/09/beautiful-face-wallpapers_11213_1280x1024.jpg

By using threshold, colour segmentation i already can get the target of the eyes with square box!
So how am i gonna crop the eyes?

ImageAnalyst

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Nov 24, 2009, 12:41:25 PM11/24/09
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On Nov 24, 12:01 pm, "boy boy" <wilson_sil...@yahoo.com> wrote:
> Image:http://salmaworld.files.wordpress.com/2009/09/beautiful-face-wallpape...

>
> By using threshold, colour segmentation i already can get the target of the eyes with square box!
> So how am i gonna crop the eyes?

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You can crop with imcrop() or just do
croppedImage = fullImage(row1:row2, column1:column2);

boy boy

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Nov 24, 2009, 4:53:20 PM11/24/09
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ImageAnalyst <imagea...@mailinator.com> wrote in message <01ef95b4-5eaa-4ab6...@o13g2000vbl.googlegroups.com>...


ok if i wanna crop the iris how am i gonna do it?
Coz it is round object imcrop just can't crop round object am i right imageAnalyst?

ImageAnalyst

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Nov 24, 2009, 5:10:23 PM11/24/09
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On Nov 24, 4:53 pm, "boy boy" <wilson_sil...@yahoo.com> wrote:
> ok if i wanna crop the iris how am i gonna do it?
> Coz it is round object imcrop just can't crop round object am i right imageAnalyst?

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Perhaps you need to take another look at my demo where I "crop" round
coins.
http://www.mathworks.com/matlabcentral/fileexchange/25157
You have to segment out your iris and then make a mask and then dot-
multiply the mask by your original image. This will blacken
everything else in the image except for your round iris. Of course
you know that matrices have to be rectangular, right? You can't have
a round matrix obviously. But you can have a rectangular matrix with
everything zeroed out except for a circular region. If you want, you
can go further and crop down to the bounding box of the circular
region to get another, smaller rectangular matrix.
Does that explain it well enough?

What do you really want anyway? Is a small rectangular region around
your iris with the stuff outside the circular iris blackened your
final goal? I doubt it. What are you going to do with it? You're
going to do something with it. Are you going to then create a feature
vector and compare against a database of pre-stored feature vectors??

boy boy

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Nov 25, 2009, 12:44:19 PM11/25/09
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Now i wanna to crop out the iris then store it into matlab! Then by using template matching method to campare the data store with the image taken! Just like the security system for self verification! Can u understand what i mean?

ImageAnalyst

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Nov 29, 2009, 12:09:16 PM11/29/09
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On Nov 25, 12:44 pm, "boy boy" <wilson_sil...@yahoo.com> wrote:
> Now i wanna to crop out the iris then store it into matlab! Then by using template matching method to campare the data store with the image taken! Just like the security system for self verification! Can u understand what i mean?

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If my first paragraph above in my prior response doesn't explain it,
then sorry, I don't understand. It gives you just the iris pixels as
an oval shape on a black background as a rectangular image. If this
is not what you want, then you'll have to explain it more clearly.
Maybe you can post some pseudo code or a step by step explanation of
what you want to do, and somebody can expand on that for you.

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