How to configure these parameters in LabVIEW using Call Library Function Node?

[courage]

I have been through your reply for couple times and there's only one thing that I want to ask: in my case,in order to open camera and alter its attributes,is change the DLL's extern parameter into LabVIEW's recognizable type the only way to accomplish this task?

If you have any other way that might be able to do the same, please let me know ,your reply and patience are greatly appreciated!

[rolfk]

Sorry I don't understand what you are asking. You mentioned you had C source code that allowed you to access those properties. Maybe you can show that.

[courage]

The thing is since IMAQdx can't enumerate some attributes that I want ,so rule out IMAQdx.What' left is just CLN,however,the DLL I currently have doesn't seem to be LabVIEW-compatible,so I have to rewrite it to conform to LabVIEW specification. So what I'm asking is that is rewrite DLL the only way to achieve what I want to do? And do you know any other way that might achieve same result?

[rolfk]

I can't say if it is the only way. Yes you sure have to create a DLL that exports at least one function to change those properties. This function could open the device, make the property change and then close the device. If this property persists, meaning stays set in the camera across opening and closing the device, you could most likely then do all the rest simply with IMAQdx. That would save you a lot of hassles with accessing memory buffers, translating between Windoos bitmap formats and IMAQ image formats and what else. But it could just as well be that opening the device always resets it to a default state so that the changes you do with your own DLL function are lost once IMAQdx opens the device for itself.

But that is a device driver specific implementation detail. And one that is very likely not documented in any manual to the driver, so you will have to try it out.