View Full Version : IC Capture and OpenCV on Windows 7 64 bit

March 5, 2012, 15:59:48
I experience a strange issue under Windows 7 64 bit. In particular both IC capture and my own software based on OpenCV have some kind of problem during acquisition. The issue is depicted into the attached figure.1453. As you can see with ICCapture I experience a slow acquisition rate (1 FPS) and strange pictures. With OpenCV I've got a normal acquisition rate but the problem with strange pictures still exists. It very annoying especially because if I acquire using my standard webcam software (ArcSoft WebCam companion) I've got no problem at all. My camera model is DFK-41AF02 which is connected to my laptop using an ExpressCard. Can you realize what's the problem?

Also, is it possible to use a resolution different from 1280x960 in order to acquire from two cameras?

Stefan Geissler
March 6, 2012, 08:17:09

First of all, one frame per second points to a very extrem problem with your FireWire board.
[quote]is connected to my laptop using an ExpressCard. Can you realize what's the problem?[\quote]
I would like to point to the FireWire express card. I never found a good working one. I think, the Processor Idle State Manager will be without any advancement here. Unfortunately FireWire connections play a smaller role on laptops in nower days. Therefore, good working hardware is hard to find.

I also suppose, your webcam is connected through, at least, internal USB, therefore, you do not have theses problems.

I am very sorry, but the solution I see is ti use the USB version DFK 41AU02 instead of DFK 41AF02, if you need to work on a laptop.

March 6, 2012, 10:40:41
Thank you for the quick reply. The fact is that the acquisition is perfect if I use a different acquiring software (maybe using a different or proprietary acquisition library). In addition the slow frame rate problem does not happen if I use for example OpenCV; in addition with OpenCV the number of bad frames is very limited, so maybe the problem is with ExpressCard but maybe the problem is the support of a certain set of library for ExpressCard (OpenCV is based on a very old VideoInput library over Windows).

In addition can you replay to the second question too about acquisition resolution. Thank you very much for your effort.

March 7, 2012, 09:58:39
Hi Stefan,

you were right about my ExpressCard. I've solved the problem contacting the support of the manufacturer of FireWire JMicron Chipset and everything works correctly now (both acquisition rate and image quality). They sent me an updated (not yet published driver) and made me change some settings into Windows registry.

Now can I please ask you if it is possible to use on my camera model a resolution different than the maximum one? My problem is that I need to acquire from two cameras at the same time and FireWire 400 bandwidth seems to be not enough.

Best regards,


Stefan Geissler
March 7, 2012, 15:15:45

thank you very much for your efforts and posting. Good to hear, that your FireWire works now.

I am very sorry, but the camera has one resolution only. You can not set lower resolutions. In order to run two cameras on one FireWire controller, you can reduce the frame rate of the camera.

March 8, 2012, 15:58:22
OK...sorry if I disturb you again...am I forced to set the default frame rates (15, 7.5) or is it also possible to set an intermediate frame rate (for example 10 fps)? Thanks,


Stefan Geissler
March 8, 2012, 16:17:39

only the "default" frame rates can be set.

May 19, 2012, 21:10:36
Hello Leo!

Could you tell please which kind of ExpressCard do you use? Becaus I want also connect my Laptop to my Camera, but my integreated FireWire dosn't use also with the cam.