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Image Change

Hello everyone,
 
I've come across something peculiar that can more than likely be fixed very quickly through image type or method of opening the image.
 
Here is my dilemma...
 
I acquire png images using a PixeLink Firewire Camera and stich them together through Labview.  However, the image through Labview does not match the image when I print it out or when I open it in a program such as ImageJ.
 
Labview seems to have an average pixel value between 5o and 80 pixels less (or darker, what have you).
 
This was noticed at the finishing of my project when I did line profiles to match up accuracy of images I had in Labview and images I noticed were lighter on printouts.
 
Any help with this is greatly appreciated.
 
Regards
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Hi, Steve,

Which type of the image you have? Probably your image is 16 bit image?

regards, Andrey.

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Hey Andrey,

Yes, the image is a 16 bit pixel representation.

Regards

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Dear Steve,

I think you may be running the difference in how LabVIEW and other programs interpret 16-bit images. The image data type in LabVIEW reads values using a signed interpretation, while many applications and camera drivers create 16-bit image data using unsigned values. See this KnowledgeBase for the details:

16-bit Images in NI Vision
http://digital.ni.com/public.nsf/allkb/3C727E03F004EA528625714900706CA0?OpenDocument

Hope this helps,

~Nate
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I ultimately decided to switch cameras and I'm matching line profiles properly.  The only problem I have now is the camera results in error -1074364401, NI-IMAQ IEEE-1394:  (Hex 0xBFF6800F) Attribute not supported by the camera.  I went and got the driver update from Unibrain for the camera I am using, which is a Sony XCD-SX900 1.05 Camera.  In addition, I occasionally receive and IMAQ error in MAX saying Error 0xBFF68002 Timeout.  This only occurs when I try to change the Video Mode with the live feed running.
 
Perhaps something is wrong with the IMAQ vi's I am using.  The camera is listed as a 1394 device under MAX, and I've always used 1394 VIs in LabVIEW but the error occurs at these camera attribute set ups.
 
Any help is greatly appreciated.
Thanks
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Problem solved...
It seems other cameras such as Pixelink and ISG can have adjustable settings and attributes through LabView but it turns out the Sony cameras, or at least the one I'm currently working with, can not have there settings changed like the other cameras can.  Camera is smoothly acquiring multiple images for me without error.
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