php给图片加水印

这一篇我们来看看那如何给图片添加水印，其实是把原图片和水印图片合并在一起。

先看文件check_image_addwatermark.php代码

<?php 

//修改图片效果

$db = mysql_connect('localhost','root','Ctrip07185419') or die('can not connect to database');

mysql_select_db('moviesite',$db) or die(mysql_error($db));

//上传文件的路径

$dir = 'D:\Serious\phpdev\test\images';

//设置环境变量

putenv('GDFONTPATH='.'C:\Windows\Fonts');

$font = "arial";



//upload_image.php页面传递过来的参数，如果是上传图片

if($_POST['submit'] == 'Upload')

{

    if($_FILES['uploadfile']['error'] != UPLOAD_ERR_OK)

    {

        switch($_FILES['uploadfile']['error'])

        {

            case UPLOAD_ERR_INI_SIZE:

                die('The uploaded file exceeds the upload_max_filesize directive');

            break;

            case UPLOAD_ERR_FORM_SIZE:

                die('The upload file exceeds the MAX_FILE_SIZE directive that was specified in the HTML form');

            break;

            case UPLOAD_ERR_PARTIAL:

                die('The uploaded file was only partially uploaded');

            break;

            case UPLOAD_ERR_NO_FILE:

                die('No file was uploaded');

            break;

            case UPLOAD_ERR_NO_TMP_DIR:

                die('The server is missing a temporary folder');

            break;    

            case UPLOAD_ERR_CANT_WRITE:

                die('The server fail to write the uploaded file to the disk');

            break;        

            case UPLOAD_ERR_EXTENSION:

                die('The upload stopped by extension');

            break;                

        }

    }

    $image_caption = $_POST['caption'];

    $image_username = $_POST['username'];

    $image_date = date('Y-m-d');

    list($width,$height,$type,$attr) = getimagesize($_FILES['uploadfile']['tmp_name']);

    $error = 'The file you upload is not a supported filetype';

    switch($type)

    {

        case IMAGETYPE_GIF:

            $image = imagecreatefromgif($_FILES['uploadfile']['tmp_name']) or die($error);

        break;

        case IMAGETYPE_JPEG:

            $image = imagecreatefromjpeg($_FILES['uploadfile']['tmp_name']) or die($error);

        break;

        case IMAGETYPE_PNG:

            $image = imagecreatefrompng($_FILES['uploadfile']['tmp_name']) or die($error);

        break;

        default:

        break;

    }

    $query = 'insert into images(image_caption,image_username,image_date) values("'.$image_caption.'" , "'.$image_username.'","'.$image_date.'")';

    $result = mysql_query($query,$db) or die(mysql_error($db));

    $last_id = mysql_insert_id();

    

    // $imagename = $last_id.'.jpg';

    // imagejpeg($image,$dir.'/'.$imagename);

    // imagedestroy($image);

    

    $image_id = $last_id;

    imagejpeg($image , $dir.'/'.$image_id.'.jpg');

    imagedestroy($image);

}

else  //如果图片已经上传，则从数据库中取图片名字

{

    $query = 'select image_id,image_caption,image_username,image_date from images where image_id='.$_POST['id'];

    $result = mysql_query($query,$db) or die(mysql_error($db));

    extract(mysql_fetch_assoc($result));

    list($width,$height,$type,$attr) = getimagesize($dir.'/'.$image_id.'.jpg');

}



//如果是保存图片

if($_POST['submit'] == 'Save')

{

    if(isset($_POST['id']) && ctype_digit($_POST['id']) && file_exists($dir.'/'.$_POST['id'].'.jpg'))

    {

        $image = imagecreatefromjpeg($dir.'/'.$_POST['id'].'.jpg');

    }

    else

    {

        die('invalid image specified');

    }

    $effect = (isset($_POST['effect'])) ? $_POST['effect'] : -1;

    switch($effect)

    {

        case IMG_FILTER_NEGATE:

            imagefilter($image , IMG_FILTER_NEGATE);     //将图像中所有颜色反转

        break;

        case IMG_FILTER_GRAYSCALE:

            imagefilter($image , IMG_FILTER_GRAYSCALE);  //将图像转换为灰度的

        break;

        case IMG_FILTER_EMBOSS:

            imagefilter($image , IMG_FILTER_EMBOSS);     //使图像浮雕化

        break;

        case IMG_FILTER_GAUSSIAN_BLUR:

            imagefilter($image , IMG_FILTER_GAUSSIAN_BLUR); //用高斯算法模糊图像

        break;    

    }

    

    if(isset($_POST['emb_caption']))

    {

        imagettftext($image , 12 , 0 , 20 , 20 , 0 , $font , $image_caption);

    }

    if(isset($_POST['emb_logo']))

    {

        //获取水印图片的尺寸并创建水印

        list($wmk_width , $wmk_height) = getimagesize('images/logo.png');

        $x = ($width-$wmk_width) / 2;

        $y = ($height-$wmk_height)/2;

        $wmk = imagecreatefrompng('images/logo.png');

        //把水印图片和原图片合并在一起

        imagecopymerge($image , $wmk , $x , $y , 0 , 0 , $wmk_width , $wmk_height , 20);

        //清除水印图片

        imagedestroy($wmk);

    }

    imagejpeg($image , $dir.'/'.$_POST['id'].'.jpg' , 100);

    ?>

    <html>

        <head>

            <title>Here is your pic!</title>

        </head>

        <body>

            <h1>Your image has been saved!</h1>

            <img src="images/<?php echo $_POST['id'];?>.jpg" alt="" />

        </body>

    </html>

<?php 

}

else

{

?>

    <html>

        <head>

            <title>Here is your pic!</title>

        </head>

        <body>

            <h1>So how does it feel to be famous?</h1>

            <p>Here is the picture you just uploaded to your servers:</p>

            <!--<img src="images/<?php echo $imagename;?>" alt="" style="float:left;" />-->

        </body>

    </html>

    <?php

        if($_POST['submit'] == 'Upload')

        {

            $imagename = 'images/'.$image_id.'.jpg';

        }

        else

        {

            $imagename = 'image_effect.php?id='.$image_id.'&e='.$_POST['effect'];

            if(isset($_POST['emb_caption']))

            {

                $imagename .= '&capt='.urlencode($image_caption);

            }

            if(isset($_POST['emb_logo']))

            {

                $imagename .= '&logo=1';

            }

        }

    ?>

    <img src="<?php echo $imagename;?>" style="float:left;" alt="" />

    <table>

        <tr>

            <td>Image save as:</td>

            <td><?php $image_id?></td>

        </tr>

        <tr>

            <td>Height:</td>

            <td><?php echo $height;?></td>

        </tr>

        <tr>

            <td>Widht:</td>

            <td><?php echo $width;?></td>

        </tr>

        <tr>

            <td>Upload date:</td>

            <td><?php echo $image_date;?></td>

        </tr>

    </table>

    <p>You may apply a special effect to your image from the list of option below.

    Note:saving an image with any of the filters applied <em>can be undone</em>

    </p>

    <form action="<?php echo $_SERVER['PHP_SELF'];?>" method="post">

        <div>

            <input type="hidden" name="id" value="<?php echo $image_id;?>"/>

            Filter:<select name="effect" id="">

                <option value="-1">None</option>

                <?php 

                    echo '<option value="'.IMG_FILTER_GRAYSCALE.'" ';

                    if(isset($_POST['effect']) && $_POST['effect'] == IMG_FILTER_GRAYSCALE)

                    {

                        echo 'selected="selected"';

                    }

                    echo ' >Black and white</option>';

                    

                    echo '<option value="'.IMG_FILTER_GAUSSIAN_BLUR.'"';

                    if(isset($_POST['effect']) && $_POST['effect'] == IMG_FILTER_GAUSSIAN_BLUR)

                    {

                        echo ' selected="selected"';

                    }

                    echo '>Blur</option>';

                    

                    echo '<option value="'.IMG_FILTER_EMBOSS.'"';

                    if(isset($_POST['effect']) && $_POST['effect'] == IMG_FILTER_EMBOSS)

                    {

                        echo 'selected="selected"';

                    }

                    echo '>Emboss</option>';

                    

                    echo '<option value="'.IMG_FILTER_NEGATE.'"';

                    if(isset($_POST['effect']) && $_POST['effect'] == IMG_FILTER_NEGATE)

                    {

                        echo 'selected="selected"';

                    }

                    echo '>Negative</option>';

                ?>

            </select><br />

            <?php 

                echo '<input type="checkbox" name="emb_caption"';

                if(isset($_POST['emb_caption']))

                {

                    echo ' checked="checked"';

                }

                echo ' />Embed caption in image?';

                echo '<br />';

                //添加水印选项

                echo '<input type="checkbox" name="emb_logo" ';

                if(isset($_POST['emb_logo']))

                {

                    echo 'checked="checked"';

                }

                echo ' />Embed watermarked logo in image?';

            ?>

            <input type="submit" value="Preview" name="submit" /><br /><br />

            <input type="submit" value="Save" name="submit" />

            

        </div>

    </form>

<?php 

}

?>

这里面主要是添加水印选项，如果选中添加水印则将logo.png作为水印图片和原来的图片合并在一起。

在预览文件中添加了对应的逻辑，代码如下：

<?php 

$dir = 'D:\Serious\phpdev\test\images';

//设置环境变量

putenv('GDFONTPATH='.'C:\Windows\Fonts');

$font = "arial";



if(isset($_GET['id']) && ctype_digit($_GET['id']) && file_exists($dir.'/'.$_GET['id'].'.jpg'))

{

    $image = imagecreatefromjpeg($dir.'/'.$_GET['id'].'.jpg');

}

else

{

    die('invalid image specified');

}



$effect = (isset($_GET['e'])) ? $_GET['e'] : -1;



switch($effect)

{

    case IMG_FILTER_NEGATE:

        imagefilter($image , IMG_FILTER_NEGATE);

    break;

    case IMG_FILTER_GRAYSCALE:

        imagefilter($image , IMG_FILTER_GRAYSCALE);

    break;    

    case IMG_FILTER_EMBOSS:

        imagefilter($image , IMG_FILTER_EMBOSS);

    break;    

    case IMG_FILTER_GAUSSIAN_BLUR:

        imagefilter($image , IMG_FILTER_GAUSSIAN_BLUR);

    break;    

}



if(isset($_GET['capt']))

{

    //echo $_GET['capt'];

    imagettftext($image, 12, 0, 20, 20, 0, $font, $_GET['capt']);

}

if(isset($_GET['logo']))

{

    list($widht , $height) = getimagesize($dir.'/'.$_GET['id'].'.jpg');

    list($wmk_width , $wmk_height) = getimagesize('images/logo.png');

    $x = ($widht-$wmk_width) / 2;

    $y = ($height-$wmk_height) / 2;

    

    $wmk = imagecreatefrompng('images/logo.png');

    imagecopymerge($image , $wmk , $x , $y , 0 , 0 , $wmk_width , $wmk_height , 20);

    imagedestroy($wmk);

}

header('Content-Type:image/jpeg');

imagejpeg($image , '' , 100);



?>

最后上传的水印图片效果如下：

注意主要的逻辑就是通过 imagecopymerge() 方法把两个图片合并在一起造成水印效果。来看看这个方法的方法原型和参数：

bool imagecopymerge ( resource $dst_im , resource $src_im , int $dst_x , int $dst_y , int$src_x , int $src_y , int $src_w , int $src_h , int $pct )

将 src_im 图像中坐标从 src_x，src_y 开始，宽度为 src_w，高度为 src_h 的一部分拷贝到 dst_im 图像中坐标为 dst_x 和 dst_y 的位置上。两图像将根据 pct 来决定合并程度，其值范围从 0 到 100。当 pct = 0 时，实际上什么也没做，当为 100 时对于调色板图像本函数和 imagecopy() 完全一样，它对真彩色图像实现了 alpha 透明。