php man page for imagecolorexactalpha

IMAGECOLOREXACTALPHA(3) 						 1						   IMAGECOLOREXACTALPHA(3)

imagecolorexactalpha - Get the index of the specified color + alpha

SYNOPSIS
       int imagecolorexactalpha (resource  $image, int	$red, int  $green, int	$blue, int  $alpha)

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

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.

	      o $alpha
		- A value between 0 and 127.  0 indicates completely opaque while 127 indicates completely transparent.

	The colors parameters are integers between 0 and 255 or hexadecimals between 0x00 and 0xFF.

RETURN VALUES
	Returns the index of the specified color+alpha in the palette of the image, or -1 if the color does not exist in the image's palette.

EXAMPLES
       Example #1

	      Get colors from the GD logo

	      <?php

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

	      $colors	= Array();
	      $colors[] = imagecolorexactalpha($im, 255, 0, 0, 0);
	      $colors[] = imagecolorexactalpha($im, 0, 0, 0, 127);
	      $colors[] = imagecolorexactalpha($im, 255, 255, 255, 55);
	      $colors[] = imagecolorexactalpha($im, 100, 255, 52, 20);

	      print_r($colors);

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

	      The above example will output something similar to:

	      Array
	      (
		  [0] => 16711680
		  [1] => 2130706432
		  [2] => 939524095
		  [3] => 342163252
	      )

NOTES
       Note

	      This function requires GD 2.0.1 or later (2.0.28 or later is recommended).

SEE ALSO
       imagecolorclosestalpha(3).

PHP Documentation Group 												   IMAGECOLOREXACTALPHA(3)