3000 explained code solutions for 75 technologies


php-gdHow to get pixel color


$file = '/var/www/examples/heroine.png';
$im = imagecreatefrompng($file);
$c = imagecolorat($im, 100, 100);
list($r, $g, $b) = [($c >> 16) & 0xFF, ($c >> 8) & 0xFF, $c & 0xFF];ctrl + c
$file

sample image to work with

imagecreatefrompng

creates GD image object from given PNG image

imagecolorat

returns color at a given position as an integer

100, 100

we're getting color on 100 pixels from top and 100 pixels from left

$r, $g, $b

variables will contain decoded values for R, G and B color channels


Usage example

<?php

$file = '/var/www/examples/heroine.png';
$im = imagecreatefrompng($file);
$c = imagecolorat($im, 100, 100);
list($r, $g, $b) = [($c >> 16) & 0xFF, ($c >> 8) & 0xFF, $c & 0xFF];

echo $r . ' ' . $g . ' ' . $b;
output
186 194 168