Hi
You just mention these code of lines to including the tiff image.

if( $this->image_type == IMAGETYPE_TIFF ) {
$this->image = imagecreatefromtiff($filename);
} else if( $this->image_type == IMAGETYPE_TIF ) {
$this->image = imagecreatefromtif($filename);
}


OR


if($type=="image/tif" || $type=="image/tiff"){
$image=@imagecreatefromtiff($src);
}

Thanks...