php|php 图片水印imagecopymerge和imagecopy
PHP给图片加水印常用imagecopymerge和 imagecopy两种合成方法。
imagecopymerge可以把不符合大小尺寸的图片压缩或拉伸成合适的水印大小，并对整个水印图片加透明度，但水印图片内部的透明度会被填充为默认黑色，例如带圆角的图片。
【php|php 图片水印imagecopymerge和imagecopy】imagecopy可以对原图素材裁剪，但不做压缩或填充。合成后保留png本身的透明度，例如圆角logo。
//作为打底的图片宽度600高度700
$bgsrc = https://www.it610.com/article/BASE_PATH.'/public/files/qrcode_bg.png';
$info = getimagesize($bgsrc);
$type = image_type_to_extension($info[2], false);
$createImageFunc = "imagecreatefrom{$type}";
$image = $createImageFunc($bgsrc);
//二维码
$imageMark = BASE_PATH.'/public/files/qrcode.png';
$markInfo = getimagesize($imageMark);
$markType = image_type_to_extension($markInfo[2], false);
$markCreateImageFunc = "imagecreatefrom{$markType}";
$waterSrc = https://www.it610.com/article/$markCreateImageFunc($imageMark);
$mask_width=342;
$mask_height=342;
$water = imagecreatetruecolor($mask_width, $mask_height);
//进行压缩或拉伸有填充色
imagecopyresampled($water, $waterSrc, 0, 0, 0, 0, $mask_width, $mask_height, $width, $height);
imagecopymerge($image, $water, 130, 183, 0, 0, $mask_width, $mask_height, 100);
imagedestroy($water);
//带圆角的logo
$imageMark = BASE_PATH.'/public/files/logo.png';
list($width, $height) = getimagesize($imageMark);
$markInfo = getimagesize($imageMark);
$markType = image_type_to_extension($markInfo[2], false);
$markCreateImageFunc = "imagecreatefrom{$markType}";
$waterSrc = https://www.it610.com/article/$markCreateImageFunc($imageMark);
//无任何压缩拉伸只做裁剪可透明
imagecopy($image,$waterSrc,264,324,0,0,$width, $height);
imagedestroy($waterSrc);
//添加字体水平居中
$font = BASE_PATH.'/public/files/font/msyhbd.ttf';
$fontSize=28;
$fontColor = imagecolorallocate($image, 255, 255, 255);
//设置颜色 rgb
$fontBox = imagettfbbox($fontSize, 0, $font, $team->title);
//文字水平居中实质
imagettftext($image, $fontSize, 0, ceil((600 - $fontBox[2]) / 2), 78, $fontColor, $font, $team->title);
//打印//合成水印
$outputfunc = "image{$type}";
$fullCoverPath = BASE_PATH.'/public/files/qrcode_card.png';
$outputfunc($image, $fullCoverPath);
//保存路径
imagedestroy($image);
