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nikkadim
December 13, 2012, 21:05:46
Is it possible to decrease the bandwidth from DMM-x2BUC0x cameras by using smaller ROI.
If I understand right we increase the FPS using smaller ROI, right?

Thank you.

PS: I just want to decrease the data stream from each cameras to give a rest for USB controller, to be able connect more cameras.

Stefan Geissler
December 14, 2012, 11:28:37
Yes. These are the possible video formats and their frame rates:

Video format Norm Frame rates
-------------------------------------------------------------------
Y800 (320x240) 160.0000 120.0005 80 60.00024 30.00003 30.00003
Y800 (640x480) 87.0004 60.00024 30.00003 15.00002 7.500008 5 5
Y800 (744x480) 76.00055 60.00024 30.00003 15.00002 7.500008 5 5
RGB24 (320x240) 160.0000 120.0005 80 60.00024 30.00003 30.00003
RGB24 (640x480) 87.0004 60.00024 30.00003 15.00002 7.500008 5 5
RGB24 (744x480) 76.00055 60.00024 30.00003 15.00002 7.500008 5 5
RGB32 (320x240) 160.0000 120.0005 80 60.00024 30.00003 30.00003
RGB32 (640x480) 87.0004 60.00024 30.00003 15.00002 7.500008 5 5
RGB32 (744x480) 76.00055 60.00024 30.00003 15.00002 7.500008 5 5

nikkadim
December 14, 2012, 13:55:02
Thank you.
Am I right, that with custom ROI I can count on bandwidth = sizeROI*FPS? Not more, right?

Stefan Geissler
December 14, 2012, 14:16:42
The camera does not support custom ROI.

And unfortunately it is not as simple "bandwidth = sizeROI*FPS", because the data is sent in packages, so you have also a header for each package, that requires some bandwidth too.

nikkadim
December 14, 2012, 15:20:53
When I'm talking about custom ROI i mean this feature:

1537
1538
is it only displaying feature?

Stefan Geissler
December 14, 2012, 16:40:58
This is an ROI done in software. If you have an image processing, you could forward only the interesting part of the image to it. If a DFK 72 USB camera is in use, then the ROI is a real ROI on the sensor with higher frame rates. But the DFK 22 does not support this.