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Color Matching

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Oconner512

Automotive
Jun 18, 2006
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I was wondering if its possible to make a camera or camcorder that could take a picture of a color, recognize it and match it to the same color in a database of colors?

thank you.
 
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There are devices made for color inspection...

But otherwise yes! Certainly. There are a bunch of gotchas involved though. The most important is that every thing's "color" is a function of the local illumination. Illumination can be quite complex. Normally if you want to do color studies you try to do it under strictly controlled lighting. Industry will have lighting booths that have specific lighting often left on to keep lamp aging etc., constant and predictable.

A standard method is to have a graded color card. You use your system to capture it. (It will have many different color blocks on it) Then you compare your unknown with those results.

Keith Cress
Flamin Systems, Inc.-
 
It is all a matter of the software you have. Not sure what you mean by having the camera automatically matching.

Maybe you are confusing WB (White Balance). With most digital cameras you can execute a WB calibration. The camera always subtracts a white balance frame from a shot after it is taken. The WB frame is normally fixed from the factory based on some common standards of illumination. So the average camera has settings like DAYLIGHT, FLUORESCENT, OVERCAST, which are 'assumed' WB frames. You can also do a better job by showing the camera a pure white surface in the exact lighting you wish to photograph in. It then uses that as the WB frame. This will then allow a better final color match in any photos subsequently taken in that same lighting.

Keith Cress
Flamin Systems, Inc.-
 
well heres an example of how it would work lets say i hook up a camcorder or camera to a computer than take pictures of about 15 diferent sheets of papers all different colors and than give each picture its color name and save it all in the computer than i would take a picture of on of the colors again and let the computer tell me what color i took picture of.
thank you I apreciate the response.
 
The camera, obviously, cannot do something like this on its own. You'll need to get or write some software.

Additionally, you'll need to invest in calibration cards with specific colors whose RBG equivalents are traceable to some standards. Your typical camera's RGB filters are not guaranteed to meet any color accuracy criteria.

TTFN



 
Color of a pixel is filed in digital form as a value in a range of 0 to 255 for each red, green and blue. So it is a matter of your software and your criteria what comparisions you do and how you decide that you have two identical colors.
m777182
 
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