(PHP 4 >= 4.0.6, PHP 5)
imagecolorresolvealpha — Get the index of the specified color + alpha or its closest possible alternative
This function is guaranteed to return a color index for a requested color, either the exact color or the closest possible alternative.
An image resource, returned by one of the image creation functions, such as imagecreatetruecolor().
Value of red component.
Value of green component.
Value of blue component.
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.
Returns a color index.
Пример #1 Using imagecoloresolve() to get colors from an image
<?php
// Load an image
$im = imagecreatefromgif('phplogo.gif');
// Get closest colors from the image
$colors = array();
$colors[] = imagecolorresolve($im, 255, 255, 255, 0);
$colors[] = imagecolorresolve($im, 0, 0, 200, 127);
// Output
print_r($colors);
imagedestroy($im);
?>
Результатом выполнения данного примера будет что-то подобное:
Array ( [0] => 89 [1] => 85 )
Замечание: Эта функция нуждается в GD версии 2.0.1 или выше.