禁用gif调整大小或调整大小而不会丢失动画

Question

我发现在互联网上的代码和一切工作正常，但我不想调整gif图像的大小，因为当我调整动画gif文件的大小，摧毁动画。或者，如果它很容易使调整gif动画图像不失动画,,,

这是upload.php的文件

if(isset($_POST)) 
{ 
    ############ Edit settings ############## 
    $BigImageMaxSize  = 500; //Image Maximum height or width 
    $ThumbPrefix   = "thumb_"; //Normal thumb Prefix 
    $DestinationDirectory = 'uploads/'; //specify upload directory ends with/(slash) 
    $Quality    = 90; //jpeg quality 
    ########################################## 

    //check if this is an ajax request 
    if (!isset($_SERVER['HTTP_X_REQUESTED_WITH'])){ 
     die(); 
    } 

    // check $_FILES['ImageFile'] not empty 
    if(!isset($_FILES['ImageFile']) || !is_uploaded_file($_FILES['ImageFile']['tmp_name'])) 
    { 
      die('Something wrong with uploaded file, something missing!'); // output error when above checks fail. 
    } 

    // Random number will be added after image name 
    $RandomNumber = rand(0, 9999999999); 

    $ImageName  = str_replace(' ','-',strtolower($_FILES['ImageFile']['name'])); //get image name 
    $ImageSize  = $_FILES['ImageFile']['size']; // get original image size 
    $TempSrc  = $_FILES['ImageFile']['tmp_name']; // Temp name of image file stored in PHP tmp folder 
    $ImageType  = $_FILES['ImageFile']['type']; //get file type, returns "image/png", image/jpeg, text/plain etc. 

    //Let's check allowed $ImageType, we use PHP SWITCH statement here 
    switch(strtolower($ImageType)) 
    { 
     case 'image/png': 
      //Create a new image from file 
      $CreatedImage = imagecreatefrompng($_FILES['ImageFile']['tmp_name']); 
      break; 
     case 'image/gif': 
      $CreatedImage = imagecreatefromgif($_FILES['ImageFile']['tmp_name']); 
      break;   
     case 'image/jpeg': 
     case 'image/pjpeg': 
      $CreatedImage = imagecreatefromjpeg($_FILES['ImageFile']['tmp_name']); 
      break; 
     default: 
      die('Unsupported File!'); //output error and exit 
    } 
    //PHP getimagesize() function returns height/width from image file stored in PHP tmp folder. 
    //Get first two values from image, width and height. 
    //list assign svalues to $CurWidth,$CurHeight 
    list($CurWidth,$CurHeight)=getimagesize($TempSrc); 

    //Get file extension from Image name, this will be added after random name 
    $ImageExt = substr($ImageName, strrpos($ImageName, '.')); 
    $ImageExt = str_replace('.','',$ImageExt); 

    //remove extension from filename 
    $ImageName  = preg_replace("/\\.[^.\\s]{3,4}$/", "", $ImageName); 

    //Construct a new name with random number and extension. 
    $NewImageName = $RandomNumber.'.'.$ImageExt; 

    //set the Destination Image 
    $DestRandImageName   = $DestinationDirectory.$NewImageName; // Image with destination directory 

    //Resize image to Specified Size by calling resizeImage function. 
    if(resizeImage($CurWidth,$CurHeight,$BigImageMaxSize,$DestRandImageName,$CreatedImage,$Quality,$ImageType)) 
    { 
     //Create a square Thumbnail right after, this time we are using cropImage() function 
     /* 
     We have succesfully resized and created thumbnail image 
     We can now output image to user's browser or store information in the database 
     */ 
     echo '<table width="100%" border="0" cellpadding="4" cellspacing="0">'; 
     echo '<tr>'; 
     echo '</tr><tr>'; 
     echo '<td align="center"><img src="uploads/'.$NewImageName.'" alt="Resized Image"></td>'; 
     echo '</tr>'; 
     echo '</table>'; 

     /* 
     // Insert info into database table! 
     mysql_query("INSERT INTO myImageTable (ImageName, ThumbName, ImgPath) 
     VALUES ($DestRandImageName, $thumb_DestRandImageName, 'uploads/')"); 
     */ 

    }else{ 
     die('Resize Error'); //output error 
    } 
} 


// This function will proportionally resize image 
function resizeImage($CurWidth,$CurHeight,$MaxSize,$DestFolder,$SrcImage,$Quality,$ImageType) 
{ 
    //Check Image size is not 0 
    if($CurWidth <= 0 || $CurHeight <= 0) 
    { 
     return false; 
    } 

    //Construct a proportional size of new image 
    $ImageScale   = min($MaxSize/$CurWidth, $MaxSize/$CurHeight); 
    $NewWidth   = ceil($ImageScale*$CurWidth); 
    $NewHeight   = ceil($ImageScale*$CurHeight); 
    $NewCanves   = imagecreatetruecolor($NewWidth, $NewHeight); 

    //Merci Yves pour la transparence 
    imagealphablending($NewCanves, false); 
    imagesavealpha($NewCanves,true); 
    $transparent = imagecolorallocatealpha($NewCanves, 255, 255, 255, 127); 
    imagefilledrectangle($NewCanves, 0, 0, $NewWidth, $NewHeight, $transparent); 
    // Resize Image 
    if(imagecopyresampled($NewCanves, $SrcImage,0, 0, 0, 0, $NewWidth, $NewHeight, $CurWidth, $CurHeight)) 
    { 
     switch(strtolower($ImageType)) 
     { 
      case 'image/png': 
       imagepng($NewCanves,$DestFolder); 
       break; 
      case 'image/gif': 
       imagegif($NewCanves,$DestFolder); 
       break;   
      case 'image/jpeg': 
      case 'image/pjpeg': 
       imagejpeg($NewCanves,$DestFolder,$Quality); 
       break; 
      default: 
       return false; 
     } 
    //Destroy image, frees memory 
    if(is_resource($NewCanves)) {imagedestroy($NewCanves);} 
    return true; 
    } 

} 

//This function corps image to create exact square images, no matter what its original size! 
function cropImage($CurWidth,$CurHeight,$iSize,$DestFolder,$SrcImage,$Quality,$ImageType) 
{  
    //Check Image size is not 0 
    if($CurWidth <= 0 || $CurHeight <= 0) 
    { 
     return false; 
    } 

    //abeautifulsite.net has excellent article about "Cropping an Image to Make Square bit.ly/1gTwXW9 
    if($CurWidth>$CurHeight) 
    { 
     $y_offset = 0; 
     $x_offset = ($CurWidth - $CurHeight)/2; 
     $square_size = $CurWidth - ($x_offset * 2); 
    }else{ 
     $x_offset = 0; 
     $y_offset = ($CurHeight - $CurWidth)/2; 
     $square_size = $CurHeight - ($y_offset * 2); 
    } 

    $NewCanves = imagecreatetruecolor($iSize, $iSize); 
    if(imagecopyresampled($NewCanves, $SrcImage,0, 0, $x_offset, $y_offset, $iSize, $iSize, $square_size, $square_size)) 
    { 
     switch(strtolower($ImageType)) 
     { 
      case 'image/png': 
       imagepng($NewCanves,$DestFolder); 
       break; 
      case 'image/gif': 
       imagegif($NewCanves,$DestFolder); 
       break;   
      case 'image/jpeg': 
      case 'image/pjpeg': 
       imagejpeg($NewCanves,$DestFolder,$Quality); 
       break; 
      default: 
       return false; 
     } 
    //Destroy image, frees memory 
    if(is_resource($NewCanves)) {imagedestroy($NewCanves);} 
    return true; 

    } 

} 

非常感谢你

Answer 1

解决方案1：

您可以使用ImageMagick调整gif文件的大小而不会丢失动画：

convert animation.gif -coalesce coalesce.gif 
convert -size 128x128 coalesce.gif -resize 96x96 small.gif 

要在PHP脚本中执行此操作，请使用system()函数。

解决方案2：

如果你不想调整gif动画，你也可以改变你先切换到这一点：

switch(strtolower($ImageType)) 
{ 
    case 'image/png': 
     //Create a new image from file 
     $CreatedImage = imagecreatefrompng($_FILES['ImageFile']['tmp_name']); 
     break;   
    case 'image/jpeg': 
    case 'image/pjpeg': 
     $CreatedImage = imagecreatefromjpeg($_FILES['ImageFile']['tmp_name']); 
     break; 
    case 'image/gif': 
     $tmp_name = $_FILES['ImageFile']["tmp_name"]; 
     $name = $_FILES['ImageFile']["name"]; 
     move_uploaded_file($tmp_name, "$DestinationDirectory/$name"); 
     break; 
    default: 
     die('Unsupported File!'); //output error and exit 
} 

这将会使你的脚本只需将上传文件到目标文件夹如果您尝试转换gif图像。

如果你这样做，你应该在开关后加上这样的事情，以防止如果$CreatedImage没有设置要执行的代码的其余部分：

if(isset($CreatedImage)){ 
    // The rest of the code from inside if(isset($_POST)){ ... } 
}