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Timeout error while acquiring from Blackmagic grabber card

Hi

 

I am using IMAQdx Grab2 vi to continuously acquire images from a Blackmagic Decklink grabber card. 

 

The basic snippet is added below:

tdb_0-1646982311594.png

 

This sub-vi is called repeatedly to generate avi files each of about 10 sec. The session open- close are done at the application start/stop respectively. So once a session is opened, it is not closed till the application exits. The avi file creation is done in a different subvi by dequeueing the image data. 

 

This code runs fine for first 15-20 minutes when called continuously in a loop. Then the Grab2 function starts returning a few timeout errors (Error code: ) in between. The number of timeout error go on increasing over time and finally I get only timeout errors continuously.  

 

Things I tried:

- same code works if I acquire images from a Basler camera instead of the grabber card.

Tried only Grab2 in a loop over 8 hours, with the Configure, Start, Stop, Unconfigure steps outside the loop. This worked perfectly with the grabber card. But my code needs the other steps inside the loop as sometimes I need to take a One-shot image too. 

- Increased timeout to 5000 ms. Still getting timeout

- Tried increasing/decreasing buffer size

- Used IMQADx GetImage2 instead of Grab2. Still getting same error.

 

I am using LabVIEW  2019 32 bit with NI Vision 19.5

 

Any suggestions on what could be the problem?

 

 

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Message 1 of 5
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Hello, etc.b. You set 500ms for the timeout. I think the problem occurs there. Can you try vary this setting? And why are you using the "wait until" function with 250ms? How did you find this value?

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Message 2 of 5
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Hi Vazgen

 

I need the timeout to be less than 700 ms as I am trying to capture an event which lasts for 700 ms max. 

 

I tried increasing the timeout to even 5000ms. But once timeout starts occurring, nothing seems to recover it. 

 

The wait of 250 ms is used as I need to capture 4 frames per sec. 

 

 

 

 

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Message 3 of 5
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What Grabber Card do you use? Can you send me the whole code including the SubVI?

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Message 4 of 5
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Hi Vazgen

 

Sorry for the late reply. 

 

The grabber card is Blackmagic decklink 8k pro. https://www.blackmagicdesign.com/in/products/decklink/techspecs/W-DLK-34

 

I cannot share the code on an open forum. Hence I had posted the snippet in the first post. I will be able to share more subvis with you if you share your official email id.

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