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Why do I have lost frames with my PCIe-1427?

I am using the Low Level Ring example in C (NI-IMAQ example).
My system includes a line scan camera (max. 47000 frames/sec, 1024 pixels, and 14 bits) and PCIe-1427 with Visual C++ 6.0.
No matter what frame rate I have (I tested down to 18 frames/sec), I always have lost frames. The camera provides frame stamp so that I can see how many frames are lost.
Increasing the number of ImaqBuffers and Reducing the size of each ImaqBuffer do not help.
Whenever ImaqBuffer changes (for example, ImaqBuffers[0] to ImaqBuffers[1]), I lost one or two frames.
Is there any way not to lose any frame?
What causes the lost frame?
 
Thank you
 
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have you gone through this thread
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Hello Hanking3:
 
This is Doug from Goodrich/SUI, the manufacturer of the camera.  We have recently become aware of this issue and investigating.  It can be observed with all of the CL cards we've tested.  The lost lines only show for the fastest camera line rate settings and can be minimized by: 
1) changing the ICD value for the TOP parameter from 1 to 0 in this line:       AcquisitionWindow (28, 1, 1024, 100)    s/b (28, 0, 1024, 100).
2) the last parameter of that line is the image height or number of lines in each image buffer.  More lines per image reduces the load on the operating system and a size of 1000 lines runs at 47 images per second
3) we've used the LL Ring.vi routine.
 
With the above, the number of lost lines is limited to 1.  We are communicating with NI support to see if there is a way to eliminate all lost lines. 
 
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Hello hanking3,

 

What brand and model camera are you using? Does the camera work in the Measurement & Automation Explorer (MAX)? What programming environment are you using? Since your camera conveniently places a frame stamp on each frame, we should verify that it works correctly in MAX before moving into the programming environment.

David G
Sales Engineer - SE Michigan & N Ohio
National Instruments
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