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How do i do the pattern matching?

Hi ,

I'm working on finger print recognition project.I'm using Ni-Vision Assitant 7.0 for this. After image analysis and image processing done to my source image i get an output image where i could see ridge bifurcations and ridge endings.Now i want to compare other finger print images too if they do have the same number of ridge endings or ridge bifurcations.I want to get a matching score.I tried pattern matching .But when i select a template the pattern matching functions creates a template which is entirely blank.I'm attaching the source image and my vision assistant script for reference.
Any help in this regard is greatly appreaciated.


Regards
Rajesh Sannareddy
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Hello Rajesh,

Pattern matching is designed for use with greyscale images. Thus, a binary image will appear in the template window as a greyscale image with intensities of 0 and 1 when the total range is 0 to 255 (for an 8-bit image). This is why the template appeared to be all black.

In order to do what you have described, I would suggest converting your script into LabVIEW code, where you could store the number of ridge endings and bifurcations (obtained from the Particle Analysis step) and then compare those values to those obtained from future tests.

You could also try performing shape matching where you would pick several key particles that are left after performing the Remove Small Objects step and look for those specific items in subsequent images. If this script were ported over to LabVIEW, you could also keep track of relative coordinate positions and angles between each other.

Regards,
Scott R.
Applications Engineer
National Instruments
Scott Romine
Course Development Engineer
National Instruments
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i had problems accessing the binary menu for all sub functions to manipulate my tiff, bmp & apid images. Is there anyway you could help me with it?
 
Appreciate it. Thanks,
Darren Lim
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Darren,

Can you please provide a little more information about what you are doing?  Are you using LabVIEW?  What functions are you using?  What are you referring to when you say "binary menu"?

Thanks,
Luke H
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i also having problem with it.please provide sample vi to Minutiae extraction.

regards

engineering student

ganesh chary

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