Dynamically-generated color look-up table

• US 6,642,931 B1
• Filed: 10/05/2000
• Issued: 11/04/2003
• Est. Priority Date: 10/05/2000
• Status: Active Grant

• Current Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Original Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Inventors: Wang, Rong, Haikin, John S.
• Primary Examiner(s): Mancuso, Joseph
• Assistant Examiner(s): CASCHERA, ANTONIO A
• Application Number:
  US09/679,910
• Time in Patent Office: 1,125 Days
• Field of Search: 345/602, 345/603, 345/604, 345/591, 345/601, 345/606, 382/162, 358/518
• US Class Current: 345/601
• CPC Class Codes: H04N 1/60 Colour correction or control H04N1/54 takes precedence

Abstract

The present invention comprises a method, for use in a color management system executing in a computer system, for generating at runtime, using device profile information, a look-up table for conversion of color data from one color space to another, the method comprising assigning a weight to each of table size, speed and accuracy factors, determining, for plural table sizes, corresponding speed and accuracy scores using the color management system, determining, for each of the plural table sizes, an aggregate of weighted scores corresponding to table size and speed and accuracy, selecting one of the plural table sizes using the aggregate of each of the plural table sizes, and generating a look-up table having the selected one of the plural table sizes.

Claims

1. A method, for use in a color management system executing in a computer system, for dynamically generating, using device profile information, a look-up table for conversion of color data from one color space to another, the method comprising:

assigning a weight to each of table size, speed and accuracy factors;

determining, for plural table sizes, corresponding speed and accuracy scores using the color management system;

determining, for each of the plural table sizes, an aggregate of weighted scores corresponding to table size and speed and accuracy;

selecting one of the plural table sizes using the aggregate of each of the plural table sizes;

generating a look-up table having a selected one of the plural table sizes.

2. A method according to claim 1, wherein determining, for plural table sizes, corresponding speed and accuracy scores using the color management system further comprises:

generating, using the device profile, a table for each of the plural table sizes;

converting color data using transformation operations of the color management system;

determining a time score associated with converting the color data using the table;

determining an accuracy score associated with converting the color data using the table.

3. The method according to claim 2, wherein determining an accuracy score associated with converting the color data using the table further comprises:

transforming color data using transformation operations of the color management system and the device profile;

determining a difference between the transformed color data and the converted color data.

4. A method according to claim 1, wherein a weight assigned to each of table size, speed and accuracy scores is determined using a user interface.

5. A method according to claim 1, wherein a weight assigned to each of table size, speed and accuracy scores is retained in storage for access by the color management system.

6. A method according to claim 1, wherein a weight assigned to each of table size, speed and accuracy scores is determined based on a determination of resources of the computer system.

7. A method for use in a color management system executing in a computer system, for dynamically generating at runtime, using device profile information, a look-up table for conversion of color data from one color space to another, the method comprising:

building a transformation using the device profile;

selecting, at runtime, a grid interval from a plurality of grid intervals, the selected grid interval corresponding to a step value between grid points for a color look-up table;

generating device dependent color data, as a range of values stepping by the selected grid interval; and

converting the device dependent color data into device independent color data using the transformation; and

building the color look-up table using the device independent color data.

8. A method according to claim 7, further comprising:

obtaining input of a user with respect to a plurality of factors,

wherein the grid interval and a grid size are determined based on the plurality of factors.

9. A method according to claim 8, wherein the plurality of factors include speed.

10. A computer-readable memory medium in which computer-executable process steps are stored, the process steps for use in a color management system executing in a computer system, for dynamically generating, using device profile information, a look-up table for conversion of color data from one color space to another, wherein the process steps comprise:

an assigning step to assign a weight to each of table size, speed and accuracy factors;

a first determining step to determine, for plural table sizes, corresponding speed and accuracy scores using the color management system;

a second determining step to determine, for each of the plural table sizes, an aggregate of weighted scores corresponding to table size and speed and accuracy;

a selecting step to select one of the plural table sizes using the aggregate of each of the plural table sizes;

a generating step to generate a look-up table having a selected one of the plural table sizes.

11. A computer-readable memory medium according to claim 10, wherein determining, for plural table sizes, corresponding speed and accuracy scores using the color management system further comprises:

a generating step to generate, using the device profile, a table for each of the plural table sizes;

a converting step to convert color data using transformation operations of the color management system;

a determining step to determine a time score associated with converting the color data using the table;

a determining step to determine an accuracy score associated with converting the color data using the table.

12. A computer-readable memory medium according to claim 11, wherein the step to determine an accuracy score associated with converting the color data using the table further comprises:

a transforming step to transform color data using transformation operations of the color management system and the device profile;

a determining step to determine a difference between the transformed color data and the converted color data.

13. A computer-readable memory medium according to claim 10, wherein a weight assigned to each of table size, speed and accuracy scores is determined using a user interface.

14. A computer-readable memory medium according to claim 10, wherein a weight assigned to each of table size, speed and accuracy scores is retained in storage for access by the color management system.

15. A computer-readable memory medium according to claim 10, wherein a weight assigned to each of table size, speed and accuracy scores is determined based on a determination of resources of the computer system.

16. Computer-executable program code stored on a computer readable medium, said computer-executable program code for use in a color management system executing in a computer system, for dynamically generating, using device profile information, a look-up table for conversion of color data from one color space to another, the computer-executable program code comprising:

code to assign a weight to each of table size, speed and accuracy factors;

code to determine, for plural table sizes, corresponding speed and accuracy scores using the color management system;

code to determine, for each of the plural table sizes, an aggregate of weighted scores corresponding to table size and speed and accuracy;

code to select one of the plural table sizes using the aggregate of each of the plural table sizes;

code to generate a look-up table having a selected one of the plural table sizes.

17. Computer-executable program code according to claim 16, wherein the code to determine, for plural table sizes, corresponding speed and accuracy scores using the color management system further comprises:

code to generate, using the device profile, a table for each of the plural table sizes;

code to convert color data using transformation operations of the color management system;

code to determine a time score associated with converting the color data using the table;

code to determine an accuracy score associated with converting the color data using the table.

18. Computer-executable program code according to claim 17, wherein the step to determine an accuracy score associated with converting the color data using the table further comprises:

code to transform color data using transformation operations of the color management system and the device profile;

code to determine a difference between the transformed color data and the converted color data.

19. Computer-executable program code according to claim 16, wherein a weight assigned to each of table size, speed and accuracy scores is determined using a user interface.

20. Computer-executable program code according to claim 16, wherein a weight assigned to each of table size, speed and accuracy scores is retained in storage for access by the color management system.

21. Computer-executable program code according to claim 16, wherein a weight assigned to each of table size, speed and accuracy scores is determined based on a determination of resources of the computer system.

22. A computer-readable memory medium in which computer-executable process steps are stored, the process steps for use in a color management system executing in a computer system, for dynamically generating at runtime, using device profile information, a look-up table for conversion of color data from one color space to another, wherein the process steps comprise:

a building step to build a transformation using the device profile;

a selecting step of selecting, at runtime, a grid interval from a plurality of grid intervals, the selected grid interval corresponding to a step value between grid points for a color look-up table;

a generating step to generate device dependent color data, as a range of values stepping by the selected grid interval;

a converting step to convert the device dependent color data into device independent color data using the transformation; and

a building step to build the color look-up table using the device independent color data.

23. Computer-executable program code stored on a computer readable medium, said computer-executable program code for use in a color management system executing in a computer system, for dynamically generating at runtime, using device profile information, a look-up table for conversion of color data from one color space to another, said computer-executable program code comprising:

code to build a transformation using the device profile;

code to select, at runtime, a grid interval from a plurality of grid intervals, the selected grid interval corresponding to a step value between grid points for a color look-up table;

code to generate device dependent color data, as a range of values stepping by the selected grid interval;

code to convert the device dependent data into device independent color data using the transformation; and

code to build the color look-up table using the converted color data.