PHP example function to add watermark to pictures_PHP tutorial-PHP Tutorial-php.cn

To add watermarks to images in PHP, we need to use many functions, such as imagecreatefromjpeg, imagecreatefrompng, getimagesize and other functions. These are all functions belonging to the PHP GD library, so we must open the GD library in php.ini Only then can PHP use these functions to generate image watermarks.

To implement the watermark function, we mainly rely on these functions

1.imagecreatefromjpeg // Open JPG image 2.imagecreatefromgif // Open GIF image
3.imagecreatefrompng // Open PNG image
4.imagecreatefromwbmp // Open WBMP image (less commonly used)
5.getimagesize // Get image size information
6.imagecopymerge // Integrate multiple images (the main function of adding watermarks)
7.imagejpeg // Save JPG image
8.imagegif // Save GIF image
9.imagepng // Save PNG image

代码如下

复制代码

echo img_water_mark("1.jpg","walter.gif",null,"2.jpg",5,80);

/**
* 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;
}

Currently supports jpg, gif, png and other image formats.

Usage example:

The code is as follows

Copy code

代码如下	复制代码
if($pic = watermark('./image.jpg','./watermark.png')) { echo '' ; } else { echo ''; }

if($pic = watermark('./image.jpg','./watermark.png'))
{
echo '

' ;
}
else
{
echo '

';
}

The following demonstrates a complete full watermark adding function

The code is as follows

Copy code

/***************************************************** **********

Parameter description:
$max_file_size : upload file size limit, unit BYTE
$destination_folder: Upload file path
$watermark : Whether to add a watermark (1 means adding watermark, others means not adding watermark);

Instructions for use:
1. Remove the ; number in front of the "extension=php_gd2.dll" line in the PHP.INI file, because we need to use the GD library;
2. Change extension_dir = to the directory where your php_gd2.dll is located;
*************************************************** ************/

//Upload file type list
$uptypes=array(
'image/jpg',
'image/jpeg',
'image/png',
'image/pjpeg',
'image/gif',
'image/bmp',
'image/x-png'
);

$max_file_size=2000000; //Upload file size limit, unit BYTE
$destination_folder="uploadimg/"; //Upload file path
$watermark=1; //Whether to add a watermark (1 means adding watermark, others means not adding watermark);
$watertype=1; //Watermark type (1 is text, 2 is picture)
$waterposition=1; //Watermark position (1 is the lower left corner, 2 is the lower right corner, 3 is the upper left corner, 4 is the upper right corner, 5 is the center);
$waterstring="http://www.bKjia.c0m/"; //Watermark string
$waterimg="xplore.gif"; //Watermark image
$imgpreview=1; //Whether to generate a preview image (1 is generated, others are not generated);
$imgpreviewsize=1/1; //Thumbnail ratio
?>

Picture watermarking program demonstration!WWW.MOP8.COM

This demonstration space is provided by TuWoo, and this program uses text watermarking.
if ($_SERVER['REQUEST_METHOD'] == 'POST')
{
If (!is_uploaded_file($_FILES["upfile"][tmp_name]))
//Does the file exist?
{
echo "The picture does not exist!";
exit;
}

$file = $_FILES["upfile"];
If($max_file_size < $file["size"])
//Check file size
{
echo "The file is too large!";
exit;
}

if(!in_array($file["type"], $uptypes))
//Check file type
{
echo "File type does not match!".$file["type"];
exit;
}

if(!file_exists($destination_folder))
{
mkdir($destination_folder); }

$filename=$file["tmp_name"];

$image_size = getimagesize($filename);
$pinfo=pathinfo($file["name"]);
$ftype=$pinfo['extension'];
$destination = $destination_folder.time().".".$ftype;
if (file_exists($destination) && $overwrite != true)
{
echo "The file with the same name already exists";
exit;
}

if(!move_uploaded_file ($filename, $destination))

{
echo "Error moving file";
exit;
}

$pinfo=pathinfo($destination);

$fname=$pinfo[basename];
echo " has been uploaded successfully
File name: ".$destination_folder.$fname."
" ;
echo " width:".$image_size[0];
echo " length: ".$image_size[1];
echo "
Size:".$file["size"]." bytes";

if($watermark==1)

{
        $iinfo=getimagesize($destination,$iinfo);                                             $nimage=imagecreatetruecolor($image_size[0],$image_size[1]);                                                          $white=imagecolorallocate($nimage,255,255,255);                                                     $black=imagecolorallocate($nimage,0,0,0);
        $red=imagecolorallocate($nimage,255,0,0);                                                Imagefill($nimage,0,0,$white);
Switch ($iinfo[2])
                                                                                        case 1:
              $simage =imagecreatefromgif($destination);                                      Break;
case 2:
$simage =imagecreatefromjpeg($destination);
Break;
case 3:
$simage =imagecreatefrompng($destination);
Break;
case 6:
$simage =imagecreatefromwbmp($destination);
Break;
                   default:                                                                 die("Unsupported file type");                              exit;

imagecopy($nimage,$simage,0,0,0,0,$image_size[0],$image_size[1]);
Imagefilledrectangle($nimage,1,$image_size[1]-15,80,$image_size[1],$white);

       switch($watertype)
       {
           case 1:   //加水印字符串
           imagestring($nimage,2,3,$image_size[1]-15,$waterstring,$black);
           break;
           case 2:   //加水印图片
           $simage1 =imagecreatefromgif("xplore.gif");
           imagecopy($nimage,$simage1,0,0,0,0,85,15);
           imagedestroy($simage1);
           break;
       }

       switch ($iinfo[2])
       {
           case 1:
           //imagegif($nimage, $destination);
           imagejpeg($nimage, $destination);
           break;
           case 2:
           imagejpeg($nimage, $destination);
           break;
           case 3:
           imagepng($nimage, $destination);
           break;
           case 6:
           imagewbmp($nimage, $destination);
           //imagejpeg($nimage, $destination);
           break;
       }

       //覆盖原上传文件
       imagedestroy($nimage);
       imagedestroy($simage);
   }

   if($imgpreview==1)
   {
   echo "
图片预览:
";
   echo " 图片预览:r文件名: ";
   }
}
?>

Related labels：

php function add picture exist Increase Example accomplish us have watermark of want

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