https://blog.faceutil.com/2017/03/26/cool-edit-2-1%ec%bf%a8%ec%97%90%eb%94%94%ed%8a%b8-%ed%81%ac%eb%9e%99-%eb%8b%a4%ec%9a%b4%eb%a1%9c%eb%93%9c-%e3%82%a5/