分享PHP实现图片添加水印 压缩 剪切的封装类

php对图片文件的操作主要是利用GD库扩展。当我们频繁利用php对图片进行操作时，会自然封装很多函数，否则会写太多重复的代码。当有很多对图片的相关函数的时候，我们可以考虑将这些函数也整理一下，因而就有了封装成类的想法。

　　操作图片主要历经四个步骤：

        第一步：打开图片

        第二步：操作图片

        第三步：输出图片

        第四步：销毁图片

　　1,3,4三个步骤每次都要写，每次又都差不多。真正需要变通的只有操作图片的这一步骤了。操作图片又往往通过1或多个主要的GD函数来完成。

　　本文封装类里面的四种方法，文字水印（imagettftext()），图片水印（imagecopymerge()），图片压缩，图片剪切(imagecopyresampled())，其余的常用GD函数便不赘述。

直接上代码：

<?php 
class Image
{  
  private $info;
  private $image;
  public $type;
  public function __construct($src)
  {
    $this->info=getimagesize($src);
    $this->type=image_type_to_extension($this->info['2'],false);
    $fun="imagecreatefrom{$this->type}";
    $this->image=$fun($src);
  }
  /**
   * 文字水印
   * @param [type] $font   字体
   * @param [type] $content 内容
   * @param [type] $size   文字大小
   * @param [type] $col   文字颜色（四元数组）
   * @param array  $location 位置 
   * @param integer $angle  倾斜角度
   * @return [type]      
   */
  public function fontMark($font,$content,$size,$col,$location,$angle=0){
    $col=imagecolorallocatealpha($this->image, $col['0'], $col['1'], $col['2'],$col['3']);
    imagettftext($this->image, $size, $angle, $location['0'], $location['1'], $col,$font,$content);
  }
  /**
   * 图片水印
   * @param [type] $imageMark 水印图片地址
   * @param [type] $dst    水印图片在原图片中的位置
   * @param [type] $pct    透明度
   * @return [type]      
   */
  public function imageMark($imageMark,$dst,$pct){
    $info2=getimagesize($imageMark);
    $type=image_type_to_extension($info2['2'],false);
    $func2="imagecreatefrom".$type;
    $water=$func2($imageMark);
    imagecopymerge($this->image, $water, $dst[0], $dst[1], 0, 0, $info2['0'], $info2['1'], $pct);
    imagedestroy($water);
  }
  /**
   * 压缩图片
   * @param [type] $thumbSize 压缩图片大小
   * @return [type]      [description]
   */
  public function thumb($thumbSize){
    $imageThumb=imagecreatetruecolor($thumbSize[0], $thumbSize[1]);
    imagecopyresampled($imageThumb, $this->image, 0, 0, 0, 0, $thumbSize[0], $thumbSize[1], $this->info['0'], $this->info['1']);
    imagedestroy($this->image);
    $this->image=$imageThumb;
  }
  /**
  * 裁剪图片
   * @param [type] $cutSize 裁剪大小
   * @param [type] $location 裁剪位置
   * @return [type]      [description]
   */
   public function cut($cutSize,$location){
     $imageCut=imagecreatetruecolor($cutSize[0],$cutSize[1]);
     imagecopyresampled($imageCut, $this->image, 0, 0, $location[0], $location[1],$cutSize[0],$cutSize[1],$cutSize[0],$cutSize[1]);
     imagedestroy($this->image);
     $this->image=$imageCut;
   }
  /**
   * 展现图片
   * @return [type] [description]
   */
  public function show(){
    header("content-type:".$this->info['mime']);
    $funn="image".$this->type;
    $funn($this->image);
  }
  /**
   * 保存图片
 * @param [type] $newname 新图片名
 * @return [type]     [description]
 */
   public function save($newname){
     header("content-type:".$this->info['mime']);
     $funn="image".$this->type;
     $funn($this->image,$newname.'.'.$this->type);
   }
   public function __destruct(){
     imagedestroy($this->image);
   }
 }
 ?>

如果还需要其他操作，只需要再往这个类里面添加就好啦~~

给图片添加水印代码：

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。