https://blog.faceutil.com/2017/04/30/adobe-photo-shop-cs6%eb%a5%bc-%ec%a0%95%ec%8b%9d%ec%9c%bc%eb%a1%9c-%ec%84%a4%ec%b9%98%ed%95%b4%eb%b3%b4%ec%9e%90-%e3%8e%b5/