Color prediction model creation using a first model to create a second model

1. A color prediction model creation device configured to create a color prediction model for predicting color values of a device-independent color system from an ink amount set that is combinations of ink amounts for inks used in printing, the color prediction model creation device comprising:

a processor configured to acquire a first spectral reflectance that is a color measurement value of a color chart printed on a first printing medium by using a predetermined first ink amount set, and create a first color prediction model that is the color prediction model used for the first printing medium by learning a correspondence relationship between the first ink amount set and the first spectral reflectance,

the processor being further configured to acquire a second spectral reflectance that is a color measurement value of a color chart printed on a second printing medium that is different from the first printing medium by using a predetermined second ink amount set having a smaller number of combinations than that of the first ink amount set, and create a second color prediction model that is the color prediction model used for the second printing medium by learning using the second ink amount set, the second spectral reflectance and the first color prediction model.

2. The color prediction model creation device according to claim 1 , wherein

the learning to create the second color prediction model is any one of a transfer learning, a fine tuning, and a combined learning of the transfer learning and the fine tuning.

3. The color prediction model creation device according to claim 1 , wherein

the processor is further configured to create, using the second color prediction model, a color conversion table for a conversion from the color values in the device-independent color system to color values in a CMYK color system.

4. A color prediction model creation system configured to create a color prediction model for predicting color values of a device-independent color system from an ink amount set that is combinations of ink amounts for inks used in printing, comprising:

a server computer provided with a storage unit in which a first color prediction model, which is the color prediction model used for a first printing medium, is stored; and

a client computer configured to input a spectral reflectance that is a color measurement value of the color chart printed on a second printing medium, which is different from the first printing medium, by using a predetermined ink amount set, wherein

the color prediction model creation system is configured to create a second color prediction model that is the color prediction model used for the second printing medium by learning using the ink amount set, the spectral reflectance, and the first color prediction model.

5. The color prediction model creation system according to claim 4 , wherein

the color prediction model creation system is configured to store the created second color prediction model in the storage unit in the server computer.

6. The color prediction model creation system according to claim 5 , wherein

the storage unit in the server computer stores a plurality of second color prediction models, and

the color prediction model creation system is configured to:

select one second color prediction model among the plurality of second color prediction models, and

create a second color prediction model that is the color prediction model used for the second printing medium by learning using the ink amount set, the spectral reflectance, and the one second color prediction model.

7. The color prediction model creation system according to claim 4 , wherein

any one of the server computer and the client computer further includes

a processor configured to create a color conversion table for a conversion from the color values in the device-independent color system to color values in a CMYK color system.

8. A color prediction model creation method for creating a color prediction model for predicting color values of a device-independent color system from an ink amount set that is combinations of ink amounts for inks used in printing, the color prediction model creation method comprising:

a first model creation step of acquiring a first spectral reflectance that is a color measurement value of a color chart printed on a first printing medium by using a predetermined first ink amount set, and creating a first color prediction model that is the color prediction model used for the first printing medium by learning a correspondence relationship between the first ink amount set and the first spectral reflectance; and

a second model creation step of acquiring a second spectral reflectance that is a color measurement value of a color chart printed on a second printing medium that is different from the first printing medium by using a predetermined second ink amount set having a smaller number of combinations than that of the first ink amount set, and creating a second color prediction model that is the color prediction model used for the second printing medium by learning using the second ink amount set, the second spectral reflectance and the first color prediction model.