如何php在二维码上添加部分透明的logo

这是用的二维码

做了一张四角和中心透明的、白色边框的图片用来嵌入到二维码图片里
但是合成后原来中心黑白的位置全变成透明,如下图

这种情况如何处理，代码如下
list($qrwidth,$qrheight) = getimagesize($imgs['qrcode']);
list($bowidth,$boheight) = getimagesize($imgs['border']);
$QR = imagecreatefrompng($imgs['qrcode']);
$border = imagecreatefrompng($imgs['border']);
$logo_qr_width = $qrwidth / 5;
$scale = $logo_width/$logo_qr_width;
$logo_qr_height = $logo_height/$scale;
$from_width = ($qrwidth - $logo_qr_width) / 2;
imagesavealpha($border,true);
imagecopyresampled($QR, $border, $from_width, $from_width, 0, 0, $logo_qr_width,$logo_qr_height, $bowidth, $boheight);
Header("Content-type: image/png");
ImagePng($QR);

回复讨论(解决方案)

这个效果？

$QR = imagecreatefrompng('http://img.bbs.csdn.net/upload/201601/04/1451892452_282416.jpg');$border = imagecreatefrompng('http://img.bbs.csdn.net/upload/201601/04/1451892077_864770.png');list($qrwidth, $qrheight) = array(imagesx($QR), imagesy($QR));list($bowidth, $boheight) = array(imagesx($border), imagesy($border));$logo_qr_width = $qrwidth / 5;$scale = $bowidth/$logo_qr_width;$logo_qr_height = $boheight/$scale;$from_width = ($qrwidth - $logo_qr_width) / 2;imagesavealpha($border,true);imagecolortransparent($border, imagecolorat($border, 1, 1));imagecopyresampled($QR, $border, $from_width, $from_width, 0, 0, $logo_qr_width,$logo_qr_height, $bowidth, $boheight);ImagePng($QR);

其实直接在 $QR 上画图不是更简单？

其实直接在 $QR 上画图不是更简单？

确实是上面的效果，刚接触php的画图，还不太了解

这个效果？

$QR = imagecreatefrompng('http://img.bbs.csdn.net/upload/201601/04/1451892452_282416.jpg');$border = imagecreatefrompng('http://img.bbs.csdn.net/upload/201601/04/1451892077_864770.png');list($qrwidth, $qrheight) = array(imagesx($QR), imagesy($QR));list($bowidth, $boheight) = array(imagesx($border), imagesy($border));$logo_qr_width = $qrwidth / 5;$scale = $bowidth/$logo_qr_width;$logo_qr_height = $boheight/$scale;$from_width = ($qrwidth - $logo_qr_width) / 2;imagesavealpha($border,true);imagecolortransparent($border, imagecolorat($border, 1, 1));imagecopyresampled($QR, $border, $from_width, $from_width, 0, 0, $logo_qr_width,$logo_qr_height, $bowidth, $boheight);ImagePng($QR);

好评，确实是上面的效果，刚接触php的画图，还有很多函数不太了解