php man page for imagecolorexact

IMAGECOLOREXACT(3)							 1							IMAGECOLOREXACT(3)

imagecolorexact - Get the index of the specified color

SYNOPSIS
       int imagecolorexact (resource  $image, int  $red, int  $green, int  $blue)

DESCRIPTION
	Returns the index of the specified color in the palette of the image.

       If you created the image from a file, only colors used in the image are resolved. Colors present only in the palette are not resolved.

PARAMETERS
	      o $
		image -An image resource, returned by one of the image creation functions, such as imagecreatetruecolor(3).

	      o $red
		-Value of red component.

	      o $green
		-Value of green component.

	      o $blue
		-Value of blue component.

RETURN VALUES
	Returns the index of the specified color in the palette, or -1 if the color does not exist.

EXAMPLES
       Example #1

	      Get colors from the GD logo

	      <?php
	      // Setup an image
	      $im = imagecreatefrompng('./gdlogo.png');

	      $colors	= Array();
	      $colors[] = imagecolorexact($im, 255, 0, 0);
	      $colors[] = imagecolorexact($im, 0, 0, 0);
	      $colors[] = imagecolorexact($im, 255, 255, 255);
	      $colors[] = imagecolorexact($im, 100, 255, 52);

	      print_r($colors);

	      // Free from memory
	      imagedestroy($im);
	      ?>

	      The above example will output something similar to:

	      Array
	      (
		  [0] => 16711680
		  [1] => 0
		  [2] => 16777215
		  [3] => 6618932
	      )

SEE ALSO
       imagecolorclosest(3).

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