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  1. Path: sparky!uunet!ferkel.ucsb.edu!taco!rock!concert!uvaarpa!darwin.sura.net!zaphod.mps.ohio-state.edu!magnus.acs.ohio-state.edu!cis.ohio-state.edu!pacific.mps.ohio-state.edu!linac!uwm.edu!ogicse!flop.ENGR.ORST.EDU!gaia.ucs.orst.edu!umn.edu!csus.edu!netcom.com!kudzu
  2. From: kudzu@netcom.com (Michael Sierchio)
  3. Newsgroups: comp.graphics
  4. Subject: Re: What is this Grayscaling Formula called ??
  5. Message-ID: <1992Nov18.180859.25901@netcom.com>
  6. Date: 18 Nov 92 18:08:59 GMT
  7. Article-I.D.: netcom.1992Nov18.180859.25901
  8. References: <1duplpINN8h4@uwm.edu> <6760@m1.cs.man.ac.uk>
  9. Organization: True Love, and Home-Grown Tomatoes
  10. Lines: 21
  11.  
  12. In article <6760@m1.cs.man.ac.uk> lilleyc@cs.man.ac.uk (Chris Lilley) writes:
  13. >
  14. >>Grayscale =  0.299 * Red + 0.587 * Green + 0.114 * Blue ;
  15. >
  16. >It is called the NTSC formula.
  17. >
  18. >>What are the origins or the logic behind specifying these values ?
  19. >
  20. >Remember you must first gamma correct the RGB values so the light
  21. >levels are linear. Then try working around the following values
  22.  
  23. Bzzzt.  You mean so that the log luminance is linear (or near linear).
  24.  
  25. >Technical Author, ITTI Computer Graphics and Visualisation Training Project
  26.  
  27. You could use some of that training yourself...
  28. -- 
  29. +--------------------------------------------------------------------------+
  30. |  Michael Sierchio                          1563 Solano Avenue, Suite 123 |
  31. |  kudzu@netcom.com                                Berkeley, CA 94707-2116 |
  32. +--------------------------------------------------------------------------+
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