How to get RBG Pixel Color

[CyberSlug]

I will add this to the unofficial documentation.

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; User-defined function to get RGB pixel color
;
; How it works:
;  Get decimal color via AutoIt's PixelGetColor function
;  Convert result to a six-digit hexadecmial number
;  Take the digits in groups of two and convert back to decmial
;    to obtain the B, G, and R (respectively) color values
;
; Anyone want to post a more direct RGB function?


$c =   PixelGetRGB(0,0);upper left pixel 
MsgBox(0,"The RBG Pixel Color is", $c[1] & "," & $c[2] & "," & $c[3])
Exit


; Returns an array with element1=RED, element2=GREEN, element3=BLUE
Func PixelGetRGB($x, $y)
   $hex = Hex(PixelGetColor($x, $y), 6)
   $r = hexToDec(StringRight($hex, 2)) & "|"
   $g = hexToDec(StringMid($hex, 3,2)) & "|"
   $b = hexToDec(StringLeft($hex, 2))
   Return StringSplit($r & $g & $b, "|")
EndFunc


; Returns the decimal equivalent of a $hex string like "05ff"
Func hexToDec($hex)
   $dec = 0;running total
   $n = StringLen($hex);number of digits

   For $i = 1 to $n
      $d = StringMid($hex, $i, 1);digit
      Select
         Case $d >= "0" And $d <= "9"
            $dec = $dec + (Asc($d)-48) * power(16,$n-$i) 
         Case $d >= "A" And $d <= "G"
            $dec = $dec + (Asc($d)-55) * power(16,$n-$i) 
         Case $d >= "a" And $d <= "g"
            $dec = $dec + (Asc($d)-87) * power(16,$n-$i) 
      EndSelect   
   Next
   Return $dec
EndFunc


; Returns $base raised to the power of $exponent
Func power($base, $exponent)
   $tmp = 1
   For $i = 1 to $exponent
      $tmp = $tmp * $base
   Next
   Return $tmp
EndFunc

Converting RGB to decimal (for use with PixelSearch) is a bit easier

Func rgbToDec($r, $g, $b)
   return HexToDec(Hex($b,2) & Hex($g,2) & Hex($r,2))
EndFunc

Edited December 27, 2003 by CyberSlug