The invention makes it possible to perform a quantitative evaluation not influenced by experience and sensitivity of a user, upon adjustment of a profile. The adjustment of first conversion data, for converting device independent data included in a profile describing characteristics of a device into device dependent data, is achieved by inputting sample data which is the device independent data, converting the sample data into the device dependent data using the first conversion data, converting the converted device dependent data into the device independent data using second conversion data which is conversion data included in the profile and which is conversion data for converting the device dependent data into the device independent data, and calculating a color difference between the sample data and the device independent data.