上傳時縮小圖片尺寸

Question

上傳時是否可以縮小圖片尺寸？

上傳文件時，大小可以從2MB減小到500kb或更少或類似 ？

Answer 1

當然，它工作正常。我使用這個類在PHP中：

<?php 

    function thumbnail($img, $source, $dest, $maxw, $maxh) {  
     $jpg = $source.$img; 

     if($jpg) { 
      list($width, $height ) = getimagesize($jpg); //$type will return the type of the image 
      $source = imagecreatefromjpeg($jpg); 

      if($maxw >= $width && $maxh >= $height) { 
       $ratio = 1; 
      }elseif($width > $height) { 
       $ratio = $maxw/$width; 
      }else { 
       $ratio = $maxh/$height; 
      } 

      $thumb_width = round($width * $ratio); //get the smaller value from cal # floor() 
      $thumb_height = round($height * $ratio); 

      $thumb = imagecreatetruecolor($thumb_width, $thumb_height); 
      imagecopyresampled($thumb, $source, 0, 0, 0, 0, $thumb_width, $thumb_height, $width, $height); 

      $path = $dest.$img."_thumb.jpg"; 
      imagejpeg($thumb, $path, 75); 
     } 
     imagedestroy($thumb); 
     imagedestroy($source); 
    } 

?> 

imagejpeg($thumb, $path, 75);就是多少，你想要的大小和上傳後的圖像質量。

在調用PHP腳本：

if(isset($_FILES['img-content'])) { 
    $img = str_replace(" ","_",$_FILES['img-content']['name']); 
    move_uploaded_file($_FILES['img-content']['tmp_name'], "../../images/content/".$img); 
    $source = "../../images/content/"; 
    $dest = "../../images/thumb/"; 
    thumbnail($img, $source, $dest, 480, 400); 

}