Machine Vision

[Elise25]

In general, what does the IMAQdx "Internal Error" mean, and how should this be debugged?  I am getting this error when controlling a camera using C++ and the IMAQdx library, and am not sure how to figure out what is going wrong.  Thanks for any input.

[Wee-Bey]

Hi there!

Is there anything else that comes with the internal error, or do you have an idea of exactly what function is producing the error message? These will likely factor into why the internal error is coming from.

[Elise25]

Hi Ravi,

Thanks for your reply.  I was getting the error when using the IMAQdxConfigureAcquisition function in a Qt program.  Using the same camera in a separate C++ program, I get IMAQdxErrorSuccess from the same function, so I know its not an issue with the camera itself.  Although I found the page in the IMAQdx help about the error codes, many of the error descriptions, such as "internal error", don't really help much with figuring out how to fix the problem.  So, if you could provide any insight, that would be great.

Thank you!

Elise 

[Elise25]

Hi Ravi,

Thanks for your reply.  I was getting the error when using the IMAQdxConfigureAcquisition function in a Qt program.  Using the same camera in a separate C++ program, I get IMAQdxErrorSuccess from the same function, so I know its not an issue with the camera itself.  Although I found the page in the IMAQdx help about the error codes, many of the error descriptions, such as "internal error", don't really help much with figuring out how to fix the problem.  So, if you could provide any insight, that would be great.

Thank you!

Elise 

[BlueCheese]

What sort of camera are you using?

The two most likely possibilities I can think of:

- You might be using a camera that relies on other external software/drivers (like most DirectShow cameras) and perhaps there is something being loaded in your process (perhaps via Qt, for instance, since you mentioned it) that is somehow conflicting with the camera drivers.

- Your porgram might be corrupting memory or the stack and causing IMAQdx to get into a bad state.

Eric

[Elise25]

Hi Eric,

Thanks for your reply.  This error comes up with 3 different firewire cameras, all of which come up as "National Instruments IMAQ Interfaces: NI-IMAQdx IIDC Digital Camera" devices in the computer's device manager. Using the same Qt program, I can actually use a USB camera (DirectShow) with no issues (IMAQdxConfigureAcquisition, IMAQdxStartAcquisition, IMAQdxGetImageData, etc. with IMAQdxErrorSuccess).  I will look into your suggestions about conflicts with the camera drivers and memory corruption. Let me know if you think of anything else.
Thanks,

Elise

[Elise25]

Hi Eric,

Thanks for your reply.  This error comes up with 3 different firewire cameras, all of which come up as "National Instruments IMAQ Interfaces: NI-IMAQdx IIDC Digital Camera" devices in the computer's device manager. Using the same Qt program, I can actually use a USB camera (DirectShow) with no issues (IMAQdxConfigureAcquisition, IMAQdxStartAcquisition, IMAQdxGetImageData, etc. with IMAQdxErrorSuccess).  I will look into your suggestions about conflicts with the camera drivers and memory corruption. Let me know if you think of anything else.
Thanks,

Elise

[BlueCheese]

Do you see the same error in MAX? Since you are using an IIDC FireWire camera with NI's driver then there should be no other drivers loaded by the camera in that process.

Eric

[Elise25]

No, I don't have any errors in MAX or LabVIEW.  So, it sounds like the IMAQdx "internal error" doesn't have a specific indication? 

Elise

[Elise25]

No, I don't have any errors in MAX or LabVIEW.  So, it sounds like the IMAQdx "internal error" doesn't have a specific indication? 

Elise

[BlueCheese]

Not generally; it generally means there was some unexpected error that should not occur. Are you changing any camera settings differently in your app vs MAX? Could you try posting a small section of code that can reproduce this error? Maybe something will be obvious there.... Eric