Open a thread from C++

[Kristian Bahus Lygre]

I am trying to develop a access-sytem based on fingerprint identification.

I find that LW is a good interface to the administrator, but the algorithms
for recognising the print is made in c-code.

How can I get LW to start the tread for recognising? Anyone?

THX

[Labviewguru]

What is LW? If you are referring to LabWindows, there is a discussion group for LabWindows which is probably more appropriate for getting your answer quicker (a lot of us LabVIEW users don't know a thing about text based languages, myself included.

Also, when you post your answer there, try to elaborate a little more. The more information you give, the better the chance of getting the answer you needed.

Sorry I wasn't much help, and hope you can find your answer on the LabWindows thread.

Also, try putting in a support request to NI at ni.com/ask. They are quite helpful.

[Kristian Bahus Lygre]

Sorry, I meant LabView. I'm using LabView 6i.

My system is supposed to work like this:

I have nodes at doors, connected in an rs485 network. These nodes capture an
300*300, 8-bit image of the fingerprint, so the size is 89kb. The node sends
this image to the computer. LabView is controlling the network.

Now the problem is that i have have the tool for recognizing and processing
the image written in C, so i want to send the image to this program, and
return a value for the respected user. This value (unique to each user),
will then be handeled in LabView, using a presentation of images and some
gimmicks. But most importantly, LabView is creating a log of who went in
where at what time and etc.

So:
I get a file from the node, stored as default
.tif in LabView. Then I want
LabView to activate the other program, and let the other program use the
image for processing.

Is ActiveX controllers a possibility?

Hope this describes my problem.

[Greg_McKaskle2]

> I have nodes at doors, connected in an rs485 network. These nodes capture an
> 300*300, 8-bit image of the fingerprint, so the size is 89kb. The node sends
> this image to the computer. LabView is controlling the network.
>
> Now the problem is that i have have the tool for recognizing and processing
> the image written in C, so i want to send the image to this program, and
> return a value for the respected user. This value (unique to each user),
> will then be handeled in LabView, using a presentation of images and some
> gimmicks. But most importantly, LabView is creating a log of who went in
> where at what time and etc.
>
> So:
> I get a file from the node, stored as default.tif in LabView. Then I want
> LabView to activate the other program, and let the other program use the
> image for processing.
>
> Is ActiveX controllers a possibility?
>



There are many ways.

If the external code is an executable, then you can use the system exec
node to run a command line that includes your executable, the file of
the image, and the result file. LV can then read the result file
periodically looking for the results. I believe that later versions
also have a way to notify LV when the EXE completes.

Another, more high tech way is to use ActiveX to access the services of
the executable. This of course means that the executable needs to be an
automation server.

You could also make the code into a DLL that is called from LV using the
Call Library Node. This will run in process and could therefore use
memory pointers rather than file I/O and running faster.


You could also make the DLL into an OCX or an in process ActiveX object.


Your initial question stated the question as wanting to start a thread.
While this could be worked out, it is more complicated than having a
DLL that is loaded into the LV process and is periodically called to do
the processing. This is the typical approach for code written by NI,
and is what I would recommend.

Greg McKaskle

[Enrique]

Kristian;

I already developed fingerprint recognition toolkit for LabVIEW. Visit www.biometricsview.com for more information.

Regards;
Vargas

[Kristian Bahus Lygre]

This seems VERY interesting.

The problem is however, that this is a school-project. We have already
bought a developers kit from Veridicom, so funding from now is a little low.

What is the asking price for the software? Can it be used with any sensor?
Ours make a 300*300 8-bit image of the fingerprint.

[Enrique]

Kristian;

The image from the Veridicom fingerprint scanner will work fine with our toolkit. However, you will need to acquire the image using other methods first in order to use the image in LabVIEW. Keep in mind that 500 dpi, 1" x 1" images are widely in used and in some places is considered the standard.

We currently fully support the CrossMatch fingerprint Scanner USB and eventually will support other scanners. Our toolkit will also work with any fingerprint scanner you can connect to an IMAQ frame grabber.

Contact me at vargas@biometricsview.com so we can discuss any details about our fingerprint recognition toolkit for your institution, including price.

Enrique Vargas
www.biometricsview.com

[dragonsantillan]

It has been more than 4 year since your post but I hope you get this. I´m working in new algortims for fingerprint recognition. i would like to know where you acquired your hardware that was able to comunicate with Labview.

Thanks.