ImagePro>Re: Hunter LAB Color Space

["Yuri Gaidoukevitch" <yuri[at]mediacy.com>]

Hi Mark,

Starting from version 4.5 IPP can be calibrated and measure XYZ and CIE Lab
color coordinates. 
We've just released Color-Pro plugin module for IPP
(http://www.mediacy.com/colorpro/colorpro.htm ) that enables color
management using color profiles (ICC,ICM) providing correct presentation of
acquired images on monitors and printers and measurements of XYZ and CIE Lab
coordinates based on color profiles.

XYZ coordinates can be converted to Hunter-Lab values using simple formulae:

(H)L = 10 * sqrt(Y)
(H)a = 17.5 * (((1.02 * X ) - Y ) / sqrt(Y))
(H)b = 7 * ((Y - (0.847 * Z))/sqrt(Y))

So, if your XYZ measurements are correct you get correct Hunter Lab values.

You can contact our colleague in UK, James Francis (+44-1189324324), for
more details over Color-Pro.

Regards,

Yuri Gaidoukevitch 
Media Cybernetics 


> -----Original Message-----
> From: Image-Pro Users List [mailto:imagepro-users@lists.mediacy.com] On
> Behalf Of Mark Kirby
> Sent: Monday, June 21, 2004 1:25 PM
> To: Image-Pro Users List
> Subject: ImagePro>Hunter LAB Color Space
> 
> Hi All,
> 
> I'm doing some work with the Hunter LAB Color Space. Essentially I found
> the
> Macbeth color chart, which obviously is very useful for calibrating RGB to
> XYZ, LAB values in terms of color. However my requirement is to calibrate
> with 'L' values only.
> 
> I have found on the archive list:
> 
> 	RE: ImagePro> Color Calibration
> 	From: Yuri Gaidoukevitch (yuri@mediacy.com)
> 	Date: 07/30/99
> 
> This is most useful but I could do with some further
> information/assistance
> on Hunter LAB specifically.
> 
> So if anyone has done work with this color space and or has Hunter LAB
> color
> charts I'd be most grateful.
> Ideally sample bitmap/tiff images showing a range of Hunter L values would
> be great.
> 
> FYI the formulas I've used are off the www.easyrgb.com web site.
> 
> Best Regards,
> 
> Mark Kirby
> Director
> Imagica Solutions Limited
> Direct: +44 (0)20 83912773
> Mobile: +44 (0)7779 260076
> Email: mark@imagicasolutions.co.uk
> 
> 
> 
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***********************************************************
This list is a forum for sharing applications, advice, and tips involving Media Cybernetics' products. It is not meant to be used as a vehicle for techncial support or for sales of third party products or services.
***********************************************************
Need an Image-Pro macro or driver? Find it at http://www.Solutions-Zone.com
Got an Image-Pro macro or driver? Add it to http://www.Solutions-Zone.com
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