PHP Image Crop from Resize

[joro]

Alright, I am having a problem modifying this code to make it work. This script is one that allows me to upload a full size image and from it create a thumbnail version. I want the image to scale proportionally but I want the script to crop from the center for larger images. So, for example, right now I upload a horizontal image and I wind up with an image that is 150 x 99 or flipped if vertical.

What can I add to this code to make it center crop so that the thumbnail is exactly 150 x 150?

<?php
class Image {
        var $FileName;
        var $FileSize;
        var $FileType;
        var $AllowedExtentions = array ("image/png", "image/gif", "image/jpeg", "image/pjpeg", "image/jpg"); 
        var $newWidth = 150; // new width 
        var $newHeight;
        var $TmpName;
        var $PicDir;  //store uploaded images
        var $MaxFileSize = 2000000;  //kbytes   
		var $ImageQuality = 100;  // image compression (max value 100)

        function Image($FileName) {
            $this->FileName=$FileName;
        }
        
        function GetInfo() {
            $out='  <br><br>Upload success!<br>
            			Name: '.$this->FileName.'<br>
                    file size: '.$this->FileSize.' byte<br>
                    file type: '.$this->FileType.'<br>
					<img src=' . dirname($_SERVER['PHP_SELF']) . '/' . $this->PicDir .  $this->FileName . '><br><br>';
					
            return $out;        
        }
		
		 
		 function GetFileExtention ($FileName) {
			if (in_array ($this->FileType, $this -> AllowedExtentions)) {
				return true; 		
			} 	else {
			   return false;			
			}		 	
		 
		 } 			
		 
		 function ExistFile () {
			$fileexist = $_SERVER['DOCUMENT_ROOT']  . 
						  dirname($_SERVER['PHP_SELF']) . 
						  '/' . $this->PicDir .  
						        $this->FileName;
				if (file_exists($fileexist)) { return true; }
		 	}
		 
		function GetError ($error) {
			
			switch ($error) {			
				case 0 :
					echo "Error: Invalid file type <b>$this->FileType</b>! Allow type: .jpg, .jpeg, .gif, .png  <b>$this->FileName</b><br>";
				break;
				
				case 1 :
					echo "Error: File <b>$this->FileSize</b> is too large! You must upload 1000 MB file<br>";
				break;				
				
				case 2 :
					echo "Error: Please, select a file for uploading!<br>";
				break;
									
				case 3 :
					echo "Error: File <b>$this->FileName</b> already exist!<br>";
				break;				
			}
			
		}

		
		 function Resize () {
			if (empty  ($this->TmpName)) 										{echo $this -> GetError (2);}
				else if ($this->FileSize > $this->MaxFileSize)        			{echo $this -> GetError (1);}						
				else if ($this -> GetFileExtention ($this->FileName) == false) 	{echo $this -> GetError (0);} 
				else if ($this -> ExistFile())                 				    {echo $this -> GetError (3);}
					
					else {
				
			$ext = explode(".",$this->FileName);
			$ext = end($ext);
			$ext = strtolower($ext);
			
			// Get new sizes
			list($width_orig, $height_orig) = getimagesize($this->TmpName);

			
			$ratio_orig = $width_orig/$height_orig;

				if ($this->newWidth/$this->newHeight > $ratio_orig) {
   			$this->newWidth = $this->newHeight*$ratio_orig;
				} else {
   			$this->newHeight = $this->newWidth/$ratio_orig;
				}
			
			

			$normal  = imagecreatetruecolor($this->newWidth, $this->newHeight);

			if 	 		($ext == "jpg") { $source = imagecreatefromjpeg($this->TmpName);  }
			else if 	($ext == "gif") { $source = imagecreatefromgif($this->TmpName);  }
			else if 	($ext == "png") { $source = imagecreatefrompng($this->TmpName);  }

			imagecopyresampled($normal, $source,    0, 0, 0, 0, $this->newWidth, $this->newHeight, $width_orig, $height_orig);


			if 	 		($ext == "jpg") { 
								//ob_start();
							    imagejpeg($normal, "$this->PicDir/$this->FileName", "$this->ImageQuality"); 
								//$binaryThumbnail = ob_get_contents(); 
								//ob_end_clean(); 
								}
			else if 	($ext == "gif") { imagegif ($normal, "$this->PicDir/$this->FileName", "$this->ImageQuality");  }
			else if 	($ext == "png") { imagepng ($normal, "$this->PicDir/$this->FileName", "$this->ImageQuality");  }

			imagedestroy($source);
 			
 			//echo $this -> GetInfo();
						
 		}	
	
	} 				
	 		 		       
        function Save() {		
				if (empty  ($this->TmpName)) 									{echo $this -> GetError (2);}
				else if ($this->FileSize > $this->MaxFileSize)        			{echo $this -> GetError (1);}						
				else if ($this -> GetFileExtention ($this->FileName) == false) 	{echo $this -> GetError (0);} 
				else if ($this -> ExistFile ())                 				{echo $this -> GetError (3);}         
        			
					else {
            
				copy($this->TmpName,$this->PicDir.$this->FileName);
            
				//echo $this -> GetInfo();
                  	
			 }
         }
     }

?>

 

[angelwatt]

Here's the math. You'll use the values in the imagecopyresampled function call inside the Resize function. I'll leave the implementation up to you for practice.

CenterX = round(thumb_width/2);
CenterY = round(thumb_height/2);
TopLeftX = CenterX - (150/2);
TopLeftY = CenterY - (150/2);