(PHP 4 >= 4.0.6, PHP 5, PHP 7, PHP 8)
imagecolorexactalpha — Get the index of the specified color + alpha
Returns the index of the specified color+alpha in the palette of the image.
imageA GdImage object, returned by one of the image creation functions, such as imagecreatetruecolor().
redValue of red component.
greenValue of green component.
blueValue of blue component.
alpha
A value between 0 and 127.
0 indicates completely opaque while
127 indicates completely transparent.
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.
| Version | Description |
|---|---|
| 8.0.0 |
image expects a GdImage
instance now; previously, a valid gd resource was expected.
|
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);
?>The above example will output something similar to:
Array
(
[0] => 16711680
[1] => 2130706432
[2] => 939524095
[3] => 342163252
)