php生成二维码时出现中文乱码的解决方法

$urlToEncode="https://.jb51.";
generateQRfromGoogle($urlToEncode);
function generateQRfromGoogle($chl,$widhtHeight ='150',$EC_level='L',$margin='0')
{
$url = urlencode($url);
echo '';
}

QRcode::png('code data text', 'filename.png');

QRcode::png('some othertext 1234');

public static function png($frame, $filename = false, $pixelPerPoint = 4, $outerFrame = 4, $saveandprint=FALSE, $mergePic='')
{
$image = self::image($frame, $pixelPerPoint, $outerFrame);
if($mergePic) {
$im = imagecreatefrompng($mergePic);
$w = imagesx($im);
$h = imagesy($im);
ImageAlphaBlending($image, true);
ImageAlphaBlending($im, true);
$qrw = (imagesx($image)-$w)/2;
$qrh = (imagesy($image)-$h)/2;
imagecopy($image, $im, $qrw, $qrh, 0, 0, $w, $h);
imagedestroy($im);
}
if ($filename === false) {
Header("Content-type: image/png");
ImagePng($image);
} else {
ImagePng($image, $filename);
if($saveandprint===TRUE){
header("Content-type: image/png");
ImagePng($image);
}
}
ImageDestroy($image);
}