Re: Probable Bugs & Suggestions

Ian Tester (
Fri, 19 Dec 1997 12:41:13 +1100 (EST)

On Thu, 18 Dec 1997, A. Leidenfrost wrote:

> o Automatic Color Calibration: Ok, although I know nearly nothing about
> scanning and image processing, here is my thoughts about color calibration
> for a certain printer. Suppose you have an image with three linear gradient
> bars for the three primary colors red, green and blue from full color to
> black. Print this image on the desired printer. Take the printout and scan
> it in 'Calibration Mode'. Calibration Mode compares the reference with the
> scanned gradient bar separately for each color and computes three gamma
> corretion curves one for each primary color. The set of gamma curves can
> then be saved under the name of the printer.
> What do you think about this? Would it work? What about an
> additional greyscale bar for brightness correction? Would it be hard to
> implement?
> I got this thought because the colors of our scans are pretty wrong and we
> really have problems correction them by hand.

Well... Unless you also know the characteristics of you printer, you would
only find the colour transformation for you printer PLUS your scanner.
Since most people dont't scan what they just printed, this would not be of
much use.

What you want to scan is some known reference. Then you would know the
transformation of your scanner.


8<--------8<--------8<--------8<--------8<--------8<--------8<-------- \|\ Ian Tester \|\ *8)#

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