Extremely slow camera response in MAX and in software

[AndyF]

I'm in the process of upgrading a piece of test equipment that uses two firewire cameras.

Currently the software is written in LabVIEW 7.1, it uses NI-IMAQ and it is relatively snappy, with little noticable delay in switching between the cameras in the software. Even MAX opens the cameras relatively quickly and you can snap or grab within a few seconds of cliking on the cameras and quickly change between cameras.

Without changing any of the hardware external to the PC, but putting a new windows 7 PC in place and updating the software to use NI-IMAQdx merely by replacing the IMAQ functions with IMAQdx in LabVIEW 2014, and installing the latest version of MAX has resulted in the software becoming exceptionally slow in switching cameras. When I say exceptional, I mean it takes up to 30s to configure and run each camera. Bearing in mind that the vision process takes 0.5s or less, this is unacceptable. It's just as painful changing between cameras in MAX.

I've noticed that on another system that uses a USB 3 camera, simply clicking on the camera icon in MAX takes a LONG time to respond to allow you to do anything,

On the old windows PC with MAX 5 and IMAQ clicking on a camera brings up the dialogue boxes reasonably quickly.

Does anyone have any idea what is going on? Is it an IMAQdx thing? Surely this isn't normal?

Can anyone offer any advice please?

Thanks

[Bob_Schor]

What kind of cameras?  What interface?  How many?  What is your software trying to do?

We have a system that uses 5-year-old Axis cameras with a TCP/IP interface, that we use to take videos of (animal) subjects in behavioral experiments.  The software was originally written in LabVIEW 2010, ported then to LabVIEW 2012 and now 2014.  It is running on a Dell Precision (at least 5 years old), originally under Windows XP, now under Windows 7.  Each camera runs at 30 frames/second, we can switch back and forth between cameras (to "see what they see") virtually instantly, and we capture 5-10" of AVI videos when "something interesting" happens.

We run 24 cameras simultaneously, using IMAQdx.

We have tried to migrate this software to similar multi-camera configuration using USB cameras.  However, we found that the bandwidth of the (single) USB channel coming into our PC permitted only a fraction of the 24 cameras we are running with our main system.

I don't think your problem is IMAQdx, per se.  Without more information on your system, I cannot venture a meaningful guess or recommend what you should do.

Bob Schor

P.S. -- oops, sorry, I missed that you were using firewire cameras.  Now that I think of it, we have another application that run a rather fancy firewire camera with three output channels.  I'll have to ask my colleague what data rates he is able to get from this -- I think he may be taking single frames at 10 fps or lower, but I'm not sure.  I'll check ...

[Bob_Schor · Accepted solution]

I shared your post with my FireWire Camera colleague (who is out of town, but checks e-mail regularly), and this is his reply:

Three cameras at 25fps, with RGB on a separate channel because of bandwidth.  We take avi and pngs simultaneously on multiple channels.  My suspicion is their old board might not be fully standards compliant. Not all boards work, I tried a few on hand, then picked one recommended by the vendor.  Also, no hubs as they can also choke bandwidth.

Hope this is helpful.

Bob Schor

[AndyF]

Thanks for your time to respond.

The two cameras I am using are DMX21F04 and a Prosilica DCAM1.31. The XP rig they are on is probably getting towards the 10 year old mark.

Out of curisoity, should the cameras appear in MAX like this? I'd expect them to be in a "sub-folder".

I'm not really doing anything intensive: both cameras are running at 15FPS, and all we do is fire them up, grab a few frames to look at a static object and stop them as we need them.

I didn't write the software and it needs updating for other reasons anyway. As an experiment I've just modified the software and tried opening both cameras up simultaneously but only grabbing from one camera at a time when we need to and closing the session at the end. The card doesn't appear to like it and returns a message of the ilk "Insufficient Transfer Engine Resource".

So I think your theory of the card not being up to the job or it having issues with Win 7 is well founded. I'll experiment with a few other cards and see how it goes and report back.

Thanks

Andy

[AndyF]

Just an update. After purchasing two firewire cards things have much improved. Accessing the camera in MAX isn't lightning fast, and starting the cameras up when the software starts isn't very quick either, BUT there IS a general improvement in access speed, and plus I can have two cameras active at once and switch between them as I need to, so I think that has met my needs.

Thanks for the advice.