ctypes.ArgumentError: Expected LP_HGRABBER instance instead of LP_HGRABBER

[vandoitruong]

Dear sir,

First, I ran an example 41 without error, however if I close that application and run the program gain, I got a " ctypes.ArgumentError " as below figure:

Current solution: restart the kernel every time when running the program. However, it's quite inconvenient, could you please give me some suggestions to fix this problem? Thank you so much!

[TIS-Stefan]

Hello

I guess, the frameReadyCallback is called, but the device, resp. the pointer in HGrabber is no longer valid. I would add a time.sleep(0.5) in

def Close():
    for camera in cameras:
        camera.stopCamera()        
   
    time.sleep(0.5)
    app.quit()

But that is guessing. I do not now, what the error means. Which camera models do you use? Which computer model do you use?

Stefan

[vandoitruong]

Thank you for your reply! I added your suggestion however it also occurred that problem.

I tried to add this line into the frameReadyCallback function: print('thread index:', threading.get_ident(), "\n") After exiting a program, Camera threads still exist and print out the thread index. I think the IC_StopLive function could be a reason because it can not release camera.

[TIS-Stefan]

Hello

At end of your program you should call ic.IC_ReleaseGrabber(hGrabber)

Stefan