$photo_types = array
	(
	'image/pjpeg' => 'jpg',
	'image/jpeg' => 'jpg',
	);

	$finfo = finfo_open(FILEINFO_MIME);

	if (array_key_exists(finfo_file($finfo, '../path_to_img'), $photo_types))
	{ 
	
	// DO CRAZY STUFF
	
	}