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imagecolorsforindex

(PHP 3, PHP 4 , PHP 5)

imagecolorsforindex -- Get the colors for an index

Description

array imagecolorsforindex ( resource image, int index)

This returns an associative array with red, green, blue and alpha keys that contain the appropriate values for the specified color index.

Example 1. imagecolorsforindex() example

<?php

// open an image
$im = imagecreatefrompng('nexen.png');

// get a color
$start_x = 40;
$start_y = 50;
$color_index = imagecolorat($im, $start_x, $start_y);

// make it human readable
$color_tran = imagecolorsforindex($im, $color_index);

// what is it ?
echo '<pre>';
print_r($color_tran);
echo '</pre>';

?>

This example will output : 

Array
(
    [red] => 226
    [green] => 222
    [blue] => 252
    [alpha] => 0
)

See also imagecolorat() and imagecolorexact().

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imagecolorsetUpimagecolorstotal
;
$yellow_y = 75;
$red_x    = 120;
$red_y    = 165;
$blue_x   = 187;
$blue_y   = 125;
$radius   = 150;

// allocate colors with alpha values
$yellow = imagecolorallocatealpha($image, 255, 255, 0, 75);
$red    = imagecolorallocatealpha($image, 255, 0, 0, 75);
$blue   = imagecolorallocatealpha($image, 0, 0, 255, 75);

// drawing 3 overlapped circle
imagefilledellipse($image, $yellow_x, $yellow_y, $radius, $radius, $yellow);
imagefilledellipse($image, $red_x, $red_y, $radius, $radius, $red);   
imagefilledellipse($image, $blue_x, $blue_y, $radius, $radius, $blue);

// don't forget to output a correct header!
header('Content-type: image/png');

// and finally, output the result
imagepng($image);
imagedestroy($image);
?>