protected function leadPNG()
	{
		$exif  = exif_imagetype($this->file) === IMAGETYPE_PNG;

		if ($exif)
		{
			return $this->closeCase("png", "image/png");
		}

		return null;
	}
protected function leadPNG()
	{
		$exif  = exif_imagetype($this->file) === IMAGETYPE_PNG;

		if ($exif)
		{
			return $this->closeCase("png", "image/png");
		}

		return null;
	}
protected function leadPNG ( ) { $ exif = exif_imagetype ( $ this -> file ) === IMAGETYPE_PNG ; if ( $ exif ) { return $ this -> closeCase ( "png" , "image/png" ) ; } return null ; }
Checks if thise file is a PNG.

@return boolean|null
Checks if thise file is a PNG .