PHP获取图片颜色值

<?php
$i=imagecreatefromjpeg("photo3.jpg");//测试图片，自己定义一个，注意路径
for ($x=0;$x<imagesx($i);$x++) {
for ($y=0;$y<imagesy($i);$y++) {
$rgb = imagecolorat($i,$x,$y);
$r=($rgb >>16) & 0xFF;
$g=($rgb >> & 0xFF;
$b=$rgb & 0xFF;
$rTotal += $r;
$gTotal += $g;
$bTotal += $b;
$total++;
}
}
$rAverage = round($rTotal/$total);
$gAverage = round($gTotal/$total);
$bAverage = round($bTotal/$total);
//示例：
echo $rAverage;
?>