search
HomeBackend DevelopmentPHP TutorialPHP实例解析:实现给上传图片加水印图案_PHP

给图片增加水印相信大家都了解。这里教大家给上传的图片加水印图案。

用PHP给上传图片加水印的程序是通过判断文件类型建立图形,然后把其复制到原建立的图形上,填充并建立rectangle,以备写入imagestring()或是原已经定好的图像程序当中判断水印类型:一是字符串,另是增加一个图形对象在上面。如果你对PHP的GD库比较熟悉,看懂这篇文章一点都不难了!

以下是引用片段:

以下为引用的内容:

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

参数说明:

$max_file_size : 上传文件大小限制, 单位BYTE

$destination_folder : 上传文件路径

$watermark : 是否附加水印(1为加水印,其他为不加水印);

使用说明:

1. 将PHP.INI文件里面的"extension=php_gd2.dll"一行前面的;号去掉,因为我们要用到GD库;

2. 将extension_dir =改为你的php_gd2.dll所在目录;

3. http://www.knowsky.com/php.asp;

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

//上传文件类型列表

$uptypes=array(

'image/jpg',

'image/jpeg',

'image/png',

'image/pjpeg',

'image/gif',

'image/bmp',

'image/x-png'

);

$max_file_size=2000000; //上传文件大小限制, 单位BYTE

$destination_folder="uploadimg/"; //上传文件路径

$watermark=1; //是否附加水印(1为加水印,其他为不加水印);

$watertype=1; //水印类型(1为文字,2为图片)

$waterposition=1; //水印位置(1为左下角,2为右下角,3为左上角,4为右上角,5为居中);

$waterstring="http://www.xplore.cn/"; //水印字符串

$waterimg="xplore.gif"; //水印图片

$imgpreview=1; //是否生成预览图(1为生成,其他为不生成);

$imgpreviewsize=1/2; //缩略图比例

?>

 



ZwelL图片上传程序




  上传文件:
 
 

  允许上传的文件类型为:=implode(', ',$uptypes)?>

if ($_SERVER['REQUEST_METHOD'] == 'POST')
{
    if (!is_uploaded_file($_FILES["upfile"][tmp_name]))
    //是否存在文件
    {
         echo "图片不存在!";
         exit;
    }
    $file = $_FILES["upfile"];
    if($max_file_size     //检查文件大小
    {
        echo "文件太大!";
        exit;
    }
    if(!in_array($file["type"], $uptypes))
    //检查文件类型
    {
        echo "文件类型不符!".$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) && $overwrite != true)
    {
        echo "同名文件已经存在了";
        exit;
    }
    if(!move_uploaded_file ($filename, $destination))
    {
        echo "移动文件出错";
        exit;
    }
    $pinfo=pathinfo($destination);
    $fname=$pinfo[basename];
    echo " 已经成功上传
文件名: 
".$destination_folder.$fname."
";
    echo " 宽度:".$image_size[0];
    echo " 长度:".$image_size[1];
    echo "
大小:".$file["size"]." bytes";
    if($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("不支持的文件类型");
            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 "height=".($image_size[1]*$imgpreviewsize);"
    echo " alt=\"图片预览:\r文件名:".$destination."\r上传时间:\" />";
    }
}
?>

Statement
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
How can you check if a PHP session has already started?How can you check if a PHP session has already started?Apr 30, 2025 am 12:20 AM

In PHP, you can use session_status() or session_id() to check whether the session has started. 1) Use the session_status() function. If PHP_SESSION_ACTIVE is returned, the session has been started. 2) Use the session_id() function, if a non-empty string is returned, the session has been started. Both methods can effectively check the session state, and choosing which method to use depends on the PHP version and personal preferences.

Describe a scenario where using sessions is essential in a web application.Describe a scenario where using sessions is essential in a web application.Apr 30, 2025 am 12:16 AM

Sessionsarevitalinwebapplications,especiallyfore-commerceplatforms.Theymaintainuserdataacrossrequests,crucialforshoppingcarts,authentication,andpersonalization.InFlask,sessionscanbeimplementedusingsimplecodetomanageuserloginsanddatapersistence.

How can you manage concurrent session access in PHP?How can you manage concurrent session access in PHP?Apr 30, 2025 am 12:11 AM

Managing concurrent session access in PHP can be done by the following methods: 1. Use the database to store session data, 2. Use Redis or Memcached, 3. Implement a session locking strategy. These methods help ensure data consistency and improve concurrency performance.

What are the limitations of using PHP sessions?What are the limitations of using PHP sessions?Apr 30, 2025 am 12:04 AM

PHPsessionshaveseverallimitations:1)Storageconstraintscanleadtoperformanceissues;2)Securityvulnerabilitieslikesessionfixationattacksexist;3)Scalabilityischallengingduetoserver-specificstorage;4)Sessionexpirationmanagementcanbeproblematic;5)Datapersis

Explain how load balancing affects session management and how to address it.Explain how load balancing affects session management and how to address it.Apr 29, 2025 am 12:42 AM

Load balancing affects session management, but can be resolved with session replication, session stickiness, and centralized session storage. 1. Session Replication Copy session data between servers. 2. Session stickiness directs user requests to the same server. 3. Centralized session storage uses independent servers such as Redis to store session data to ensure data sharing.

Explain the concept of session locking.Explain the concept of session locking.Apr 29, 2025 am 12:39 AM

Sessionlockingisatechniqueusedtoensureauser'ssessionremainsexclusivetooneuseratatime.Itiscrucialforpreventingdatacorruptionandsecuritybreachesinmulti-userapplications.Sessionlockingisimplementedusingserver-sidelockingmechanisms,suchasReentrantLockinJ

Are there any alternatives to PHP sessions?Are there any alternatives to PHP sessions?Apr 29, 2025 am 12:36 AM

Alternatives to PHP sessions include Cookies, Token-based Authentication, Database-based Sessions, and Redis/Memcached. 1.Cookies manage sessions by storing data on the client, which is simple but low in security. 2.Token-based Authentication uses tokens to verify users, which is highly secure but requires additional logic. 3.Database-basedSessions stores data in the database, which has good scalability but may affect performance. 4. Redis/Memcached uses distributed cache to improve performance and scalability, but requires additional matching

Define the term 'session hijacking' in the context of PHP.Define the term 'session hijacking' in the context of PHP.Apr 29, 2025 am 12:33 AM

Sessionhijacking refers to an attacker impersonating a user by obtaining the user's sessionID. Prevention methods include: 1) encrypting communication using HTTPS; 2) verifying the source of the sessionID; 3) using a secure sessionID generation algorithm; 4) regularly updating the sessionID.

See all articles

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

WebStorm Mac version

WebStorm Mac version

Useful JavaScript development tools