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imagecolorexactalpha

PHP function Edit on GitHub ✎

(PHP 4 >= 4.0.6, PHP 5, PHP 7, PHP 8)

Get the index of the specified color + alpha

Description

imagecolorexactalpha(GdImage $image, int $red, int $green, int $blue, int $alpha): int

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

Parameters

red: Red
green: Green
blue: Blue
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.

Changelog

Version	Description

Examples

Get colors from the GD logo

php

<?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:

output

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