The example in this article summarizes the function of adding watermark to PHP images. Share it with everyone for your reference, the details are as follows:
Example 1. Add a watermark function under a very simple picture
<?php /** * 追加水印 * * @param string $source_img 原始图片url * @param string $water_map 水印图片url */ function addWaterMap($source_img, $water_map) { $img = imagecreatefromjpeg($source_img); //读取原图 $img_x = imagesx($img); //原图宽 $img_y = imagesy($img); //原图高 imagealphablending($img, true);//设置为混合填色模式 //$img_water_map = imagecreatefromjpeg($water_map); //读取水印图片 $img_water_map = imagecreatefrompng($water_map); $water_x = imagesx($img_water_map); //水印宽 $water_y = imagesy($img_water_map); //水印高 $wimg_x = $img_x - $water_x - 10; //水印x坐标 $wimg_y = $img_y - $water_y - 10; //水印y坐标 imagecopy($img, $img_water_map, $wimg_x, $wimg_y, 0, 0, $water_x, $water_y); //分别为原图,水印,水印x坐标,水印y坐标,水印图片横轴开始点,水印图片纵轴开始点,水印横轴结束,水印纵轴结束 imagejpeg($img, $source_img, 95); //输出到目标文件 imagedestroy($img); //销毁内存数据流 imagedestroy($img_water_map); //销毁内存数据流 return true; } ?>
Example 2. Add a watermark class to a relatively complete picture
<?php /** * 图片加水印(适用于png/jpg/gif格式) * * @author flynetcn * * @param $srcImg 原图片 * @param $waterImg 水印图片 * @param $savepath 保存路径 * @param $savename 保存名字 * @param $positon 水印位置 * 1:顶部居左, 2:顶部居右, 3:居中, 4:底部局左, 5:底部居右 * @param $alpha 透明度 -- 0:完全透明, 100:完全不透明 * * @return 成功 -- 加水印后的新图片地址 * 失败 -- -1:原文件不存在, -2:水印图片不存在, -3:原文件图像对象建立失败 * -4:水印文件图像对象建立失败 -5:加水印后的新图片保存失败 */ function img_water_mark($srcImg, $waterImg, $savepath=null, $savename=null, $positon=5, $alpha=30) { $temp = pathinfo($srcImg); $name = $temp['basename']; $path = $temp['dirname']; $exte = $temp['extension']; $savename = $savename ? $savename : $name; $savepath = $savepath ? $savepath : $path; $savefile = $savepath .'/'. $savename; $srcinfo = @getimagesize($srcImg); if (!$srcinfo) { return -1; //原文件不存在 } $waterinfo = @getimagesize($waterImg); if (!$waterinfo) { return -2; //水印图片不存在 } $srcImgObj = image_create_from_ext($srcImg); if (!$srcImgObj) { return -3; //原文件图像对象建立失败 } $waterImgObj = image_create_from_ext($waterImg); if (!$waterImgObj) { return -4; //水印文件图像对象建立失败 } switch ($positon) { //1顶部居左 case 1: $x=$y=0; break; //2顶部居右 case 2: $x = $srcinfo[0]-$waterinfo[0]; $y = 0; break; //3居中 case 3: $x = ($srcinfo[0]-$waterinfo[0])/2; $y = ($srcinfo[1]-$waterinfo[1])/2; break; //4底部居左 case 4: $x = 0; $y = $srcinfo[1]-$waterinfo[1]; break; //5底部居右 case 5: $x = $srcinfo[0]-$waterinfo[0]; $y = $srcinfo[1]-$waterinfo[1]; break; default: $x=$y=0; } imagecopymerge($srcImgObj, $waterImgObj, $x, $y, 0, 0, $waterinfo[0], $waterinfo[1], $alpha); switch ($srcinfo[2]) { case 1: imagegif($srcImgObj, $savefile); break; case 2: imagejpeg($srcImgObj, $savefile); break; case 3: imagepng($srcImgObj, $savefile); break; default: return -5; //保存失败 } imagedestroy($srcImgObj); imagedestroy($waterImgObj); return $savefile; } function image_create_from_ext($imgfile) { $info = getimagesize($imgfile); $im = null; switch ($info[2]) { case 1: $im=imagecreatefromgif($imgfile); break; case 2: $im=imagecreatefromjpeg($imgfile); break; case 3: $im=imagecreatefrompng($imgfile); break; } return $im; }
I hope this article will be helpful to everyone in PHP program design .
For more examples and summary of PHP image adding watermark function, please pay attention to PHP Chinese website for related articles!

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