Smart Camera Performance with VBAI

[OZI]

Hi,

we are using Smart Cameras NI 1772 and VBAI 2011 for a high speed inspection. To be sure that the real time conditions are not broken we make benchmark tests from time to time. Some of the results are strange to us.

For example: we are using NI Vision to make a more detailed vision inspection and the time which the ni vision tool needs is changing. so for example one time it needs more than 100ms for execution. But when we reprogrammed this tool it needs only about 25ms. Could this be real?

How can it be possible that there are so different results?

Are there any recommendations for high speed execution in VBAI?

Thanks

Oliver

[BruceAmmons]

Execution times always depend on the algorithms used.  By changing your algorithm, you can greatly reduce the time required for the test.

In Vision, execution time is highly dependent on the number of pixels being analyzed.  Analysis of a single line of pixels is much faster than an area.  It also depends on what you do with that data.

Therefore, an improvement of 4x is not surprising when you optimized your test.

Bruce

[OZI]

Hi Bruce

it correct what you have written. But could it be possible that a step needs so different times? Do you know if there is any where a document with recommendations for high speed for VBAI?

greetings

Oliver

[ChristopheC]

Your question is very generic and difficult to answer without seeing your inspection. What do you mean by "reprogrammed".

Some algorithm might depend on the content of the image. Most algorithms in VBAI use a Region of Interest for a search area or area to inspect, and the time will be dependent on the size of that ROI.For example, if you have an apriori knowledge of where an object should be, reduce the size of the search area in a pattern matching step to increase the speed of the algorithm instead of searching the entire image.