function img_resize($src, $dest, $width, $height, $rgb = 0x000000, $quality = 100) {  
    if (!file_exists($src)) {  
        return false;  
    }  
 
    $size = getimagesize($src);  
 
    if ($size === false) {  
        return false;  
    }  
 
    $format = strtolower(substr($size['mime'], strpos($size['mime'], '/') + 1));  
    $icfunc = 'imagecreatefrom'.$format;  
 
    if (!function_exists($icfunc)) {  
        return false;  
    }  
 
    $x_ratio = $width  / $size[0];  
    $y_ratio = $height / $size[1];  
 
    if ($height == 0) {  
 
        $y_ratio = $x_ratio;  
        $height  = $y_ratio * $size[1];  
 
    } elseif ($width == 0) {  
 
        $x_ratio = $y_ratio;  
        $width   = $x_ratio * $size[0];  
 
    }  
 
    $ratio       = min($x_ratio, $y_ratio);  
    $use_x_ratio = ($x_ratio == $ratio);  
 
    $new_width   = $use_x_ratio  ? $width  : floor($size[0] * $ratio);  
    $new_height  = !$use_x_ratio ? $height : floor($size[1] * $ratio);  
    $new_left    = $use_x_ratio  ? 0 : floor(($width - $new_width)   / 2);  
    $new_top     = !$use_x_ratio ? 0 : floor(($height - $new_height) / 2);  
 
    $isrc  = $icfunc($src);  
    $idest = imagecreatetruecolor($width, $height);  
    $rgb2 = imagecolorallocate($idest, 245, 245, 245);
    imagefill($idest, 0, 0, $rgb2);  
    imagecopyresampled($idest, $isrc, $new_left, $new_top, 0, 0, $new_width, $new_height, $size[0], $size[1]);  
 
    imagejpeg($idest, $dest, $quality);  
 
    imagedestroy($isrc);  
    imagedestroy($idest);  
 
    return true;  
}