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imagecolorat

imagecolorat

(PHP 3, PHP 4, PHP 5)

imagecolorat -- Get the index of the color of a pixel

Popis

int imagecolorat ( resource image, int x, int y )

Returns the index of the color of the pixel at the specified location in the image specified by image.

If PHP is compiled against GD library 2.0 or higher and the image is a truecolor image, this function returns the RGB value of that pixel as integer. Use bitshifting and masking to access the distinct red, green and blue component values:

Seznam parametrů

image

An image resource, returned by one of the image creation functions, such as imagecreatetruecolor().

x

x-coordinate of the point

y

y-coordinate of the point

Návratové hodnoty

Returns the index of the color.

Příklady

Příklad 1. Access distinct RGB values

<?php
$im
= imagecreatefrompng("php.png");
$rgb = imagecolorat($im, 10, 15);
$r = ($rgb >> 16) & 0xFF;
$g = ($rgb >> 8) & 0xFF;
$b = $rgb & 0xFF;
?>

Výše uvedený příklad vypíše něco jako:

int(119)
int(123)
int(180)