How can i convert multi color to Black and White ??
lazarus / 39-Graphics

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majid.ebru · 2017-10-14 18:21

HI
How can i convert multi color to Black and White ?

in image down :
 how can i convert blue rang color to black&White rang color ??

thank you

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lainz · 2017-10-14 18:56

(R+G+B) / 3

Or more nice methods:
https://www.johndcook.com/blog/2009/08/24/algorithms-convert-color-
grayscale/

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BeanzMaster · 2017-11-14 13:59

Very simple

pseudo code :

Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i Const  
Thresold = 128; For y:=0 to Img.Height-1  for  x:=0 to Img.Width -1 
begin    Pixel := img.GetPixel(x,y);        Intensity :=
(Pixel.Red+Pixel.Green+Pixel.Blue) div 3;    if intensity <  Thresold
then newPixel:= clBlack else newPixel:= clWhite;   
BWImg.PutPixel(x,y,NewPixel); end;

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Thaddy · 2017-11-14 15:46

Quote from: BeanzMaster on November 14, 2017, 02:59:25 pmVery simple
It IS simple but not for gray scaling. And that was the question.
First answer is correct.

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BeanzMaster · 2017-11-14 21:02

The main question is  QuoteHow can i convert multi color to Black and
White ??  not to grayscale

The 2nd is for grayscale Quotehow can i convert blue rang color to
black&White rang color ??
So by the way now they have the choice