Using a USB Camera with IMAQ but not IMAQ for USB

[DavidU]

Hi,

I have a USB camera that I can control using the IMAQ for USB functions. However, the program will become part of a commercial product and the deployment license required for IMAQ for USB is prohibitive.

So I would like to use just the straight IMAQ functions, i.e. IMAQ init.vi, IMAQ snap.vi, etc. I fall over at the first step, I don't know what the interface name for the camera is. I have tried using the string returned by IMAQ USB enumerate cameras but with no luck.

The camera does not appear in MAX, so I can't get the name from there either.

I'm using LabVIEW 8.6, and have Vision 8.6 installed but as I mentioned I can't use anything that requires an additional license

Any ideas?

With regards to the licensing: Am I right in thinking that anything listed in this article can be used without a license? I'm a little confused because it seems to contradict this atricle

Thanks in advance

David

[ChristopheC]

NI-IMAQdx, installed with NI Vision Acquisition Software now supports DirectShow compliant cameras and has licensing that will allow you to deploy your application in a commercial product.

You can download and try the latest version from this link:

http://sine.ni.com/nips/cds/view/p/lang/en/nid/12892

Hope this helps.

Christophe

[DavidU]

Christophe,

Yes, I have seen that IMAQdx now supports USB cameras. However, according to this and this IMAQdx requires an extra deployment license. Is this correct?

I need to be able to deploy without incurring extra licensing costs. Am I correct in thinking that the IMAQ functions listed here can be used without the extra license?

Thanks

David

[ChristopheC]

> IMAQdx requires an extra deployment license. Is this correct?

This is correct, unless you already purchased a Vision Development Module runtime license, which includes a Vision Acquisition runtime license.

If you're processing the acquired images using functions from the Vision Development module, you need a VDM runtime license to deploy your application, which includes a Vision Acquisition license.

NI IMAQ does not support Directshow USB cameras. Only NI-IMAQ for USB and IMAQdx support USB devices.

Runtime licenses of Vision Acquisition Software are included with any of our hardware products, but not when you're interfacing with the camera using USB.

If deployment cost is an issue, I recommend you to get in touch with your NI sales representative and see how they can help.

-Christophe

[tcheng7992]

Hi,

I have installed IMAQdx and the latest Vision Aquisition Software.

Thank you for your updated information.

My system works fine with Vision Aquisition Express.

However, I need to both aquire and snapshot functions.

Could anybody provide me a sample code to perform these funtions by using USB camera (support DirectShow) ?

Thanks !

[tcheng7992]

Here is my sample VI.

After I press the snapshot button, the program can not back to the Vision Acquisition VI for continuously aquiring the images.

I need help to solve this problem. It may be a programming issue.

I am new to the LabVIEW.

Can anybody give me an advice of how to make this task works ?

Thanks !

[ChristopheC]

The mechanical action of your Snapshot button is set to Switch when Pressed, meaning the button stays depressed once you click on it.

To perform a single snap, change the mechanical action to "Latch when release" (Right Click>>Mechanical Action>>Latch When Released).

The code in your case structure will be executed only once, performing a snap and not at each iteration.

Also, you might want to connect your Stop button to the Stop Input of the Acquisition Express VI, so that the VI cleans up the resources when you click Stop.

-Christophe

[tcheng7992]

Thanks.

However, it is still not working after I did the modifications as you suggested.

It seems that the program will not go back to and reinitialize Vision Acquistion Express VI after took a snapshot.

Could you give me further advices about this issue ? Thank you again.

Joe

[tcheng7992]

Hi, Chris,

My program works now (see my attached VI).

However, sometimes the program will show error for too many sessions.

Please refer to the attached error meesage.

Please adivse how to clean up all the sessions after STOP the program or at the end of each snapshooting.

One more question.

How to enumerate all the cameras (with "name") and let user to select one of it if there are more than one USB cameras are installed.

Thanks !