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Unread 21-01-2012, 10:50
Greg McKaskle Greg McKaskle is offline
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Re: Labview Slow Images Capture

gnunes,
I ran the attached code only laptop with a 206 camera. I was using the DLink and had the camera and laptop plugged into the DLink. This ran fine. The attached screenshot shows that the time between frames was nominally 33ms with some jitter. The CPU usage on the computer is around 20% on my laptop. The latency measured by moving my hand was less than 1/4 second, probably more like 100 to 150 ms.

The IP camera are subject to the caching that can take place an each NIC, on the camera, switch, wifi devices, and the computer. Bring up the task manager and observe cpu usage, and experiment with wired vs wireless. It may be that your wifi was running at lower speed to be compatible with some other device on the network.

In terms of bandwidth, the jpegs on my computer were about 24kBytes large. At 30fps, that results in 720MBytes per second, or about 7.2Mbits per second. This would mostly consume a b speed network, should work on g speed, but six cameras would consume it. And finally, an n speed network should handle a number of cameras pretty well depending on its configuration.

Please post back when you discover the cause of the issue.

Greg McKaskle
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