(PHP 4 >= 4.0.6, PHP 5, PHP 7)
imagecolorresolvealpha — Get the index of the specified color + alpha or its closest possible alternative
$image
, int $red
, int $green
, int $blue
, int $alpha
)This function is guaranteed to return a color index for a requested color, either the exact color or the closest possible alternative.
imageAn image resource, returned by one of the image creation functions, such as imagecreatetruecolor().
redValue of red component.
greenValue of green component.
blueValue of blue component.
alphaA value between 0 and 127. 0 indicates completely opaque while 127 indicates completely transparent.
Returns a color index.
Example #1 Using imagecoloresolvealpha() to get colors from an image
<?php
// Load an image
$im = imagecreatefromgif('phplogo.gif');
// Get closest colors from the image
$colors = array();
$colors[] = imagecolorresolvealpha($im, 255, 255, 255, 0);
$colors[] = imagecolorresolvealpha($im, 0, 0, 200, 127);
// Output
print_r($colors);
imagedestroy($im);
?>
The above example will output something similar to:
Array
(
[0] => 89
[1] => 85
)
Note: This function requires GD 2.0.1 or later (2.0.28 or later is recommended).