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AAlex
March 12, 2008, 00:29:06
I'm developing a product that needs to track features at high framerates and subpixel accuracy AND in imperfect lighting conditions. I've tried DMK 21AU04 and it looks like it will get the job done. However, I have some follow-up questions

1) I cannot use IC now due to VS incompatibility. Any ETA on that?
2) Capturing is significantly CPU expensive at 60fps. Is FireWire more efficient?
3) I understand that the monochrome version is more sensitive, but assuming that I can take some SNR hit, how comparable is the fine detail resolution of the DMK images vs. DBK? Are there any images of the same object (like an ISO chart) taken with different cameras under same lighting conditions / gain / exposure?

4) Is capturing from DBK more CPU expensive than DMK due to debayering?

5) Is it possible to order a DBK for side-by-side evaluation?

Thanks for providing excellent support for your products!

Stefan Geissler
March 12, 2008, 11:46:10
Hi


I cannot use IC now due to VS incompatibility. Any ETA on that?
Which VS?


Capturing is significantly CPU expensive at 60fps. Is FireWire more efficient?
Only a little bit, but not realy. 60 fps contains a high load of data.


I understand that the monochrome version is more sensitive, but assuming that I can take some SNR hit, how comparable is the fine detail resolution of the DMK images vs. DBK? Are there any images of the same object (like an ISO chart) taken with different cameras under same lighting conditions / gain / exposure?
First of all: Such pictures are not available. 2.) The DBK is a color camera, thus it has a Bayermosaic filter in front of the CCD. The DMK has not such a filter.


Is capturing from DBK more CPU expensive than DMK due to debayering?
If you debayered in the computer, then cleary yes.


Is it possible to order a DBK for side-by-side evaluation?
Please ask the sales department (sales@theimagingsource.com)

AAlex
March 12, 2008, 12:18:05
Stefan, thanks for the comprehensive answer - this clears things up a lot.
I'm using VisualStudio 2008, and form what I've discovered and read the current version of IC is incompatible with it.

>> If you debayered in the computer, then cleary yes.
Wasn't as obvious to me because I wasn't sure whether debayering was done at the camera or in the IC land. From your answer I understand it is both?

Thanks again.

Alex

Stefan Geissler
March 12, 2008, 13:07:16
Alex,

The debayring can be done in the camera and in the computer. This is determined by the used video format.
UYVY = debayer in the camera
BY8 = debayer automatically by DirectShow
Y800 = raw data.

IC .NET 31 is compatible to VS2008 (C#, VB )

AAlex
April 21, 2008, 17:19:30
Stefan, I was able to ascertain debayering performance by forcing it on with my DFK source.

I was kindly notified by one of your colleagues about updated version of IC library, but it doesn't look like it has vc9 support. Can you confirm/deny? Perhaps I just have wrong URL?

I estimate throughput as 640x480*8*60/10^6 = 148Mbps + protocol overhead.
My usb drive has throughput more than twice that, but consumes less CPU. I know it is comparing apples and oragnes, but is there a chance there's any room for optimization there? Perhaps building the library with /O2 instead of /Ox or vice-versa?

Stefan Geissler
April 22, 2008, 09:15:26
Hi,

You are right, VC 9 (VS 2008) is not support yet.

The bandwidth allocation depends on the transfer method, that is used. We try, like in FireWire the transfer method, that should guarantee the transport of the desired frame rate. This takes some more overhead. More details can sure be found in the USB specification :-). To make it short, no there is no room right now.

AAlex
April 22, 2008, 15:49:38
Stefan, surely the constant framerate is higher priority and is very well worth extra overhead.

Speaking of which, I found that starting an application with maximum base thread priority really helps to avoid framerate jitters when other apps occasionally have to use too much CPU or access drives, etc.