Method for preparing profiles Number:7,385,726 from the United States Patent and Trademark Office (PTO) owispatent

Title: Method for preparing profiles

Abstract: A method for updating profiles is provided. The method involves storing a plurality of successive profiles for an image recording device, and changing at least two of the successive profiles when characteristics of the image recording device change. The profiles are successively used to process image data that is used for recording images on a recording medium by the image recording device.

Patent Number: 7,385,726 Issued on 06/10/2008 to Kuno,   et al.

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Inventors:	Kuno; Masashi (Obu, JP), Ueda; Masashi (Nagoya, JP), Nishihara; Masahiro (Nagoya, JP)
Assignee:	Brother Kogyo Kabushiki Kaisha (Nagoya, JP)
Appl. No.:	11/159,093
Filed:	June 23, 2005

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Related U.S. Patent Documents

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	Application Number	Filing Date	Patent Number	Issue Date
	09764152	Jan., 2001	6975426

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Foreign Application Priority Data

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Jan 21, 2000 [JP]			2000-17798

Current U.S. Class:	358/1.18 ; 358/1.9; 358/2.1; 715/788; 715/789
Field of Search:	358/1.15,1.13,1.16,522,524,443,444,1.12,1.18,1.14,1.9,2.1 715/788,789

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References Cited [Referenced By]

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U.S. Patent Documents

4959711	September 1990	Hung et al.
5172223	December 1992	Suzuki et al.
5416614	May 1995	Crawford
5500890	March 1996	Rogge et al.
6134017	October 2000	Schlank et al.
6433884	August 2002	Kawakami
2001/0012396	August 2001	Kumada
2003/0142332	July 2003	Endoh et al.
2003/0225835	December 2003	Klien et al.
2004/0049515	March 2004	Haff et al.
2004/0172248	September 2004	Otsuka et al.
2004/0172468	September 2004	Cai et al.

Other References

US. Appl. No. 09/757,649, filed Jan. 11, 2001, Masashi Kuno et al. cited by other.

Primary Examiner: Grant, II; Jerome
Attorney, Agent or Firm: Oliff & Berridge, PLC

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Parent Case Text

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This is a Division of application Ser. No. 09/764,152 filed Feb. 19, 2001. The entire disclosure of the prior application is hereby incorporated by reference herein in its entirety.

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Claims

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What is claimed is:

1. A method for updating profiles, comprising: storing a plurality of successive profiles for an image recording device, the profiles being successively used to process image data that is used for recording images on a recording medium by the image recording device; and changing at least two of the successive profiles when characteristics of the image recording device change, wherein the plurality of successive profiles include at least an upstream profile and a downstream profile, the upstream profile being used for performing a prior process on the image data and the downstream profile being used for performing a subsequent process on the image data already processed by the prior process, the upstream profile and the downstream profile being changed when the characteristics of the image recording device change.

2. A method as claimed in claim 1, wherein the at least two of the successive profiles are changed when the characteristics of the image recording device change over passage of time.

3. A method as claimed in claim 1, wherein the at least two of the successive profiles are changed when a model of the image recording device is changed.

4. A method as claimed in claim 1, wherein the at least two of the successive profiles are changed when a type of the image recording medium used is changed.

5. A method as claimed in claim 1, wherein the at least two of the successive profiles are changed when a type of ink used in the image recording device is changed.

6. A method as claimed in claim 1, wherein the at least two of the successive profiles are changed when a setting of a resolution in the image recording device is changed.

7. A method as claimed in claim 1, wherein the at least two of the successive profiles are changed when a setting of a printing speed in the image recording device is changed.

8. A method as claimed in claim 1, wherein the changing step includes: preparing a new downstream profile; preparing a new upstream profile using the prepared new downstream profile; and writing the new downstream profile and the new upstream profile over the already-stored downstream and upstream profiles.

9. A method as claimed in claim 8, wherein the changing step further includes judging, after the new downstream profile preparation process and before the new upstream profile preparation process, whether the new downstream profile has been properly prepared by processing image data using the prepared new downstream profile, by controlling the image recording device to record the processed image data on a recording medium, by examining a recorded result, and by judging whether or not the new downstream profile has been properly prepared based on the examined result, and when it is judged that the new downstream profile has been improperly prepared, preventing the new upstream profile preparation process from being performed based on the improperly-prepared new downstream profile.

10. A method as claimed in claim 9, wherein the prevention process includes the step of terminating preparation of the new upstream and downstream profiles.

11. A method as claimed in claim 9, wherein the judgment process restarts the new downstream profile preparation process when it is judged that the new downstream profile has been improperly prepared.

12. A method as claimed in claim 9, wherein the changing step further includes: setting the already-stored downstream profile and the upstream profile as an initial downstream profile and an initial upstream profile, respectively; and judging, after the new upstream profile preparation process, whether the prepared new upstream profile and the new downstream profile have been properly prepared by processing image data using the prepared new upstream profile in a prior process, by further processing the processed image data using the prepared new downstream profile in a subsequent process, by controlling the image recording device to record on a recording medium the image data processed using both of the new upstream profile and the new downstream profile, by examining a recorded result, and by judging whether the new upstream profile and the new downstream profile have been properly prepared based on the examined result, and when it is judged that at least one of the new upstream profile and the new downstream profile has been improperly prepared, restoring the new downstream and upstream profiles to the initial downstream and upstream profiles.

13. A method as claimed in claim 12, wherein the changing step further includes, after the restoring process, a step of terminating preparation of the new upstream profile and the new downstream profile.

14. A method as claimed in claim 12, wherein the changing step further includes, after the restoring process a step of restarting the new downstream profile preparation process.

15. A device for updating profiles, comprising: a memory that stores a plurality of successive profiles for an image recording device, the profiles being successively used to process image data that is used for recording images on a recording medium by the image recording device; and a changing unit that changes at least two of the successive profiles when characteristics of the image recording device change, wherein the plurality of successive profiles include at least an upstream profile and a downstream profile, the upstream profile being used for performing a prior process on the image data and the downstream profile being used for performing a subsequent process on the image data already processed by the prior process, the changing unit changing the upstream profile and the downstream profile when the characteristics of the image recording device change.

16. A device as claimed in claim 15, wherein the changing unit changes the at least two of the successive profiles when the characteristics of the image recording device change over passage of time.

17. A device as claimed in claim 15, wherein the changing unit changes the at least two of the successive profiles when a model of the image recording device is changed.

18. A device as claimed in claim 15, wherein the changing unit changes the at least two of the successive profiles when a type of the image recording medium used is changed.

19. A device as claimed in claim 15, wherein the changing unit changes the at least two of the successive profiles when a type of ink used in the image recording device is changed.

20. A device as claimed in claim 15, wherein the changing unit changes the at least two of the successive profiles when a setting of a resolution in the image recording device is changed.

21. A device as claimed in claim 15, wherein the changing unit changes the at least two of the successive profiles when a setting of a printing speed in the image recording device is changed.

22. A device as claimed in 15, wherein the changing unit includes: a downstream profile preparing unit preparing a new downstream profile; an upstream profile preparing unit preparing a new upstream profile using the prepared new downstream profile; and a writing unit writing the new downstream profile and the new upstream profile in the memory over the already-stored downstream and upstream profiles.

23. A device as claimed in claim 22, wherein the changing unit further includes a judging unit judging, after the new downstream profile preparation process and before the new upstream profile preparation process, whether the new downstream profile has been properly prepared by processing image data using the prepared new downstream profile, by controlling the image recording device to record the processed image data on a recording medium, by examining a recorded result, and by judging whether the new downstream profile has been properly prepared based on the examined result, and when it is judged that the new downstream profile has been improperly prepared, preventing the upstream profile preparation unit from performing the preparation based on the improperly-prepared new downstream profile.

24. A device as claimed in claim 23, wherein the judging unit controls the upstream and downstream profile preparing units to terminate preparation of the new upstream profile and the new downstream profile, thereby preventing the upstream profile preparation unit from performing the preparation based on the improperly-prepared new downstream profile.

25. A device as claimed in claim 23, wherein the judging unit controls the downstream profile preparing unit to restart the new downstream profile preparation process when it is judged that the new downstream profile has been improperly prepared.

26. A device as claimed in claim 23, wherein the changing unit further includes a setting unit setting the presently-existing downstream profile and the presently-existing upstream profile as an initial downstream profile and an initial upstream profile, respectively; and wherein the judging unit judges, after the upstream profile preparation process, whether the prepared new upstream profile and the new downstream profile have been properly prepared by processing image data using the prepared new upstream profile in a prior process, by further processing the processed image data using the prepared new downstream profile in a subsequent process, by controlling the image recording device to record on a recording medium the image data processed using both of the new upstream profile and the new downstream profile, by examining a recorded result, and by judging whether or not the new upstream profile and the new downstream profile have been properly prepared based on the examined result, and when it is judged that at least one of the new upstream profile and the new downstream profile has been improperly prepared, restores the new downstream and upstream profiles to the initial downstream and upstream profiles.

27. A device as claimed in claim 26, wherein the judging unit controls, after the restoring process, the upstream and downstream profile preparing unit to terminate the preparation of the new upstream profile and the new downstream profile.

28. A device as claimed in claim 26, wherein the judging unit controls, after the restoring process, the downstream profile preparing unit to restart the downstream profile preparation process.

29. A method for updating profiles, comprising: storing a plurality of successive profiles for an image recording device, the profiles being successively used to process image data that is used for recording images on a recording medium by the image recording device; and changing at least two of the successive profiles upon receipt of a user's instruction, wherein the plurality of successive profiles include at least an upstream profile and a downstream profile, the upstream profile being used for performing a prior process on the image data and the downstream profile being used for performing a subsequent process on the image data already processed by the prior process, wherein the changing step includes: preparing a new downstream profile; preparing a new upstream profile using the prepared new downstream profile; and writing the new downstream profile and the new upstream profile over the already-stored downstream and upstream profiles.

30. A method as claimed in claim 29, wherein the changing step further includes judging, after the new downstream profile preparation process and before the new upstream profile preparation process, whether the new downstream profile has been properly prepared by processing image data using the prepared new downstream profile, by controlling the image recording device to record the processed image data on a recording medium, by examining a recorded result, and by judging whether or not the new downstream profile has been properly prepared based on the examined result, and when it is judged that the new downstream profile has been improperly prepared, preventing the new upstream profile preparation process from being performed based on the improperly-prepared new downstream profile.

31. A method as claimed in claim 30, wherein the prevention process includes the step of terminating preparation of the new upstream and downstream profiles.

32. A method as claimed in claim 30, wherein the judgment process restarts the new downstream profile preparation process when it is judged that the new downstream profile has been improperly prepared.

33. A method as claimed in claim 30, wherein the changing step further includes: setting the already-stored downstream profile and the upstream profile as an initial downstream profile and an initial upstream profile; and judging, after the new upstream profile preparation process, whether the prepared new upstream profile and the new downstream profile have been properly prepared by processing image data using the prepared new upstream profile in a prior process, by further processing the processed image data using the prepared new downstream profile in a subsequent process, by controlling the image recording device to record on a recording medium the image data processed using both of the new upstream profile and the new downstream profile, by examining a recorded result, and by judging whether the new upstream profile and the new downstream profile have been properly prepared based on the examined result, and when it is judged that at least one of the new upstream profile and the new downstream profile has been improperly prepared, restoring the new downstream and upstream profiles to the initial downstream and upstream profiles.

34. A method as claimed in claim 33, wherein the changing step further includes, after the restoring process, the step of terminating preparation of the new upstream profile and the new downstream profile.

35. A method as claimed in claim 33, wherein the changing step further includes, after the restoring process, the step of restarting the new downstream profile preparation process.

36. A device for updating profiles, comprising: a memory that stores a plurality of successive profiles for an image recording device, the profiles being successively used to process image data that is used for recording images on a recording medium by the image recording device; and a changing unit that changes at least two of the successive profiles upon receipt of a user's instruction, wherein the plurality of successive profiles include at least an upstream profile and a downstream profile, the upstream profile being used for performing a prior process on the image data and the downstream profile being used for performing a subsequent process on the image data already processed by the prior process, and wherein the changing unit includes: a downstream profile preparing unit preparing a new downstream profile; an upstream profile preparing unit preparing a new upstream profile using the prepared new downstream profile; and a writing unit writing the new downstream profile and the new upstream profile in the memory over the already-stored downstream and upstream profiles.

37. A device as claimed in claim 36, wherein the changing unit further includes a judging unit judging, after the new downstream profile preparation process and before the new upstream profile preparation process, whether the new downstream profile has been properly prepared by processing image data using the prepared new downstream profile, by controlling the image recording device to record the processed image data on a recording medium, by examining a recorded result, and by judging whether the new downstream profile has been properly prepared based on the examined result, and when it is judged that the new downstream profile has been improperly prepared, preventing the upstream profile preparation unit from performing the preparation based on the improperly-prepared new downstream profile.

38. A device as claimed in claim 37, wherein the judging unit controls the upstream and downstream profile preparing units to terminate preparation of the new upstream profile and the new downstream profile, thereby preventing the upstream profile preparation unit from performing the preparation based on the improperly-prepared new downstream profile.

39. A device as claimed in claim 37, wherein the judging unit controls the downstream profile preparing unit to restart the new downstream profile preparation process when it is judged that the new downstream profile has been improperly prepared.

40. A device as claimed in claim 37, wherein the changing unit further includes a setting unit setting the presently-existing downstream profile and a presently-existing upstream profile as an initial downstream profile and an initial upstream profile; and wherein the judging unit judges, after the upstream profile preparation process, whether the prepared new upstream profile and the new downstream profile have been properly prepared by processing image data using the prepared new upstream profile in a prior process, by further processing the processed image data using the prepared new downstream profile in a subsequent process, by controlling the image recording device to record on a recording medium the image data processed using both of the new upstream profile and the new downstream profile, by examining a recorded result, and by judging whether or not the new upstream profile and the new downstream profile have been properly prepared based on the examined result, and when it is judged that at least one of the new upstream profile and the new downstream profile has been improperly prepared, restores the new downstream and upstream profiles to the initial downstream and upstream profiles.

41. A device as claimed in claim 40, wherein the judging unit controls, after the restoring process, the upstream and downstream profile preparing unit to terminate the preparation of the new upstream profile and the new downstream profile.

42. A device as claimed in claim 40, wherein the judging unit controls, after the restoring process, the downstream profile preparing unit to restart the downstream profile preparation process.

43. A method for updating profiles, comprising: storing a plurality of successive profiles for an image recording device, the profiles being successively used to process image data that is used for recording images on a recording medium by the image recording device; inputting an instruction when characteristics of the image recording device change; and starting to change at least two of the successive profiles in response to the input of the instruction, wherein the plurality of successive profiles include at least an upstream profile and a downstream profile, the upstream profile being used for performing a prior process on the image data and the downstream profile being used for performing a subsequent process on the image data already processed by the prior process, wherein the changing step includes: preparing a new downstream profile; preparing a new upstream profile using the prepared new downstream profile; and writing the new downstream profile and the new upstream profile over the already-stored downstream and upstream profiles.

44. A device for updating profiles, comprising: a memory that stores a plurality of successive profiles for an image recording device, the profiles being successively used to process image data that is used for recording images on a recording medium by the image recording device; an instruction input unit that receives a user's instruction when characteristics of the image recording device change; and a changing unit that changes at least two of the successive profiles upon receipt of a user's instruction, wherein the plurality of successive profiles include at least an upstream profile and a downstream profile, the upstream profile being used for performing a prior process on the image data and the downstream profile being used for performing a subsequent process on the image data already processed by the prior process, and wherein the changing unit includes; a downstream profile preparing unit preparing a new downstream profile; an upstream profile preparing unit preparing a new upstream profile using the prepared new downstream profile; and a writing unit writing the new downstream profile and the new upstream profile in the memory over the already-stored downstream and upstream profiles.

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Description

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BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method of preparing upstream profiles and downstream profiles which are used for processing image data before the image data is used in a recording process in a manner that the upstream profiles are used for performing prior processes onto image data and the downstream profiles are used for performing subsequent processes onto the image data which has already been subjected to the prior processes.

2. Description of Related Art

There has been known an image forming device, such as a color printer, that records color images on a recording medium using four colors of ink, for example, cyan (C), magenta (M), yellow (Y), and black (K) ink. It is noted that the density level, actually outputted onto the recording medium, can vary according to a variety of conditions, such as the model of the printer, the resolution, the type of ink, and the type of recording medium. Therefore, according to the variation in those conditions, it will become impossible to faithfully reproduce color images, which are retrieved using a scanner, or prepared in a computer, if they are recorded onto a recording medium according to image data inputted as is from the computer or the scanner.

For this reason, before recording an image on a recording medium based on image data inputted from a computer or the like, normally the input image data is first corrected based on profiles in order to reproduce original images as faithfully as possible.

SUMMARY OF THE INVENTION

Examples of profiles include upstream and downstream profiles. The upstream profile is used for performing prior processes on the input image data. The downstream profile is used for performing subsequent processes on the input image data, which has already been subjected to the prior processes using the upstream profile. The image data thus subjected to the downstream profile is then used for recording a corresponding image onto a recording medium.

More specifically, the upstream profile is for correcting tone of input image data in order to correct for changes due to passage of time, for unique characteristics of the image recording device itself, and for other factors. The downstream profile is for further calibrating the input image data, already subjected to the tone correction based on the upstream profile, in order to more precisely correct for the changes due to passage of time, for the unique characteristics of the image recording device itself, and for other factors.

Because the upstream profile and the downstream profile are interrelated in this way, the upstream profile, which will be used during the prior process, should be prepared after the downstream profile, which will be used during the subsequent process, is prepared.

It is an objective of the present invention to provide a method of efficiently preparing the interrelated upstream and downstream profiles.

In order to attain the above and other objects, the present invention provides a method for preparing an upstream profile and a downstream profile, both of which are for being used to process image data for recording images on a recording medium, the upstream profile being used for performing a prior process onto the image data and the downstream profile being used for performing a subsequent process on the image data already processed by the prior process, the method comprising the steps of: preparing a downstream profile; preparing an upstream profile using the prepared downstream profile; and judging, after the downstream profile preparation process and before the upstream profile preparation process, whether the downstream profile has been properly prepared, and when it is judged that the downstream profile has been improperly prepared, preventing the upstream profile preparation process from being performed based on the improperly-prepared downstream profile.

According to another aspect, the present invention provides an apparatus for preparing an upstream profile and a downstream profile, both of which are for being used to process image data for recording images on a recording medium, the upstream profile being used for performing a prior process onto the image data and the downstream profile being used for performing a subsequent process on the image data already processed by the prior process, the apparatus comprising: a downstream preparing unit preparing a downstream profile; an upstream preparing unit preparing an upstream profile using the prepared downstream profile; and a judging unit judging, after the downstream profile preparation process and before the upstream profile preparation process, whether the downstream profile has been properly prepared, and when it is judged that the downstream profile has been improperly prepared, preventing the upstream profile preparation unit from performing the preparation based on the improperly-prepared downstream profile.

According to still another aspect, the present invention provides a data storage medium storing, in a manner readable by a computer, a program of preparing an upstream profile and a downstream profile, both of which are for being used to process image data for recording images on a recording medium, the upstream profile being used for performing a prior process onto the image data and the downstream profile being used for performing a subsequent process on the image data already processed by the prior process, the program comprising: a program of preparing a downstream profile; a program of preparing an upstream profile using the prepared downstream profile; and a program of judging, after the downstream profile preparation process and before the upstream profile preparation process, whether the downstream profile has been properly prepared, and when it is judged that the downstream profile has been improperly prepared, preventing the upstream profile preparation process from being performed based on the improperly-prepared downstream profile.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and advantages of the invention will become more apparent from reading the following description of the embodiment taken in connection with the accompanying drawings in which:

FIG. 1 is a block drawing showing a profile preparation system according to an embodiment of the present invention;

FIG. 2(a) is a flowchart representing an image recording process performed by using an upstream profile and a downstream profile;

FIG. 2(b) is a schematic view showing color patches printed on a recording medium by the profile preparation system of FIG. 1;

FIG. 3 is a flowchart representing a profile preparation routine performed by the profile preparation system of FIG. 1;

FIG. 4 is a flowchart representing a modification of the profile preparation routine;

FIG. 5 is a schematic flow diagram showing an image recording process performed by using an example of the upstream profile and the downstream profile of the present embodiment;

FIG. 6 is a schematic view showing a color correction table used during the image recording processes;

FIG. 7 is graph representing a measurement curve, indicative of a relationship between color data and an output density level, and a tone-correction curve, indicative of a relationship between color data and tone-corrected color data, which is represented by a tone correction table (upstream profile);

FIG. 8 is a graph representing a relationship between color data, for each of two basic colors of magenta and cyan, and corresponding light ink data and normal ink data;

FIG. 9(a) is a schematic view showing a light ink conversion table representing the relationship, between the color data and light ink data, shown in FIG. 8;

FIG. 9(b) is a schematic view showing a normal ink conversion table representing the relationship, between the color data and normal ink data, shown in FIG. 8; and

FIG. 10 is graph representing a measurement curve, indicative of a relationship between ink data and an output density level, and a tone-correction curve, indicative of a relationship between ink data and tone-corrected ink data, which is represented by another tone correction table (downstream profile).

DETAILED DESCRIPTION OF THE EMBODIMENT

A profile preparation system according to a preferred embodiment of the present invention will be described while referring to the accompanying drawings.

As shown in FIG. 1, the profile preparation system 100 of the present embodiment includes a personal computer 1, a color printer 2, and a calorimeter 5. The personal computer 1, the color printer 2, and the colorimeter 5 are connected together by dedicated interface cables 4, 5 for data transmission.

The personal computer 1 includes a CPU 11, a ROM 12, a RAM 13, a hard disk 14, a printer interface 15, a colorimeter interface 19, a cathode-ray-tube (CRT) display 16, and an input unit 18, such as a mouse and a keyboard, all connected to a bus 17 for mutual data transmission.

The CPU 11 is for executing various control operations and calculation operations according to various programs stored in the ROM 12 and according to other various programs retrieved from the hard disk 14 and stored in the RAM 13. The ROM 12 stores the various control programs, and also various types of data.

The RAM 13 is capable of storing the various programs retrieved from the hard disk 14, and also various data obtained from calculations performed by the CPU 11.

The hard disk 14 serves as an auxiliary storage unit for storing, as files, data and programs which are not stored in main memories such as the ROM 12 or the RAM 13. More specifically, the hard disk 14 stores therein a profile preparation program for executing a profile preparation method (FIG. 3). The hard disk 14 further stores therein an upstream profile U and a downstream profile D which are prepared using the profile preparation program. The upstream profile U is for correcting for changes brought on by passage of time and for unique characteristics of the image recording device 2 itself. The downstream profile D is for more precisely correcting for the changes brought on by passage of time and for the unique characteristics of the image recording device 2.

The input unit 18 includes a mouse and a key board, with which a user can input his/her instruction into the personal computer 1.

The printer interface 15 is for performing two-way data transmission between the computer 1 and the color printer 2 according to a specific transmission protocol agreed upon by the computer 1 and the color printer 2.

The calorimeter interface 19 is for performing two-way data transmission between the computer 1 and the colorimeter 5 according to a specific transmission protocol agreed upon by the computer 1 and the calorimeter 5.

The CRT 16 is for displaying various types of data in a form visually recognizable by the user of the system 100.

The color printer 2 includes an ink-jet type print unit 21 and a PC interface 22. The print unit 21 is capable of performing data transmission with the personal computer 1 through the PC interface 22 and the printer interface 15.

The print unit 21 is of a type that forms images on a recording medium by ejecting inks of cyan (C), magenta (M), yellow (Y), and black (K). The print unit 21 can record multi-tone color images, having density levels of 256 tones for each of four colors, by selectively ejecting dots of the corresponding ink.

The colorimeter 5 includes a retrieval unit 31 and a PC interface 32. The retrieval unit 31 performs transmission of data with the personal computer 1 via the PC interface 32 and the colorimeter interface 19.

The retrieval unit 31 is for measuring the intensity of light transmitted through or reflected from an object, dividing the colors of the object into three primary colors (RGB), and outputting the density level of each color as a measured color database.

The upstream profile U and the downstream profile D are used during an image recording process for recording images as shown in FIG. 2(a). The image recording process of FIG. 2(a) is executed also by the profile preparation system 100.

During the image recording process, a set of image data for the four colors of cyan, magenta, yellow, and black is subjected to a prior process in S50. During the prior process, the image data is corrected according to the upstream profile U. The image data is then subjected to a subsequent process in S60. During the subsequent process, the image data is further corrected according to the downstream profile D. After the subsequent process, the image data is supplied to the printer 2 in S70. As a result, the image data is recorded into a color image. The upstream and downstream profiles U and D can correct for changes brought on by passage of time and for unique characteristics of the image recording device 2 itself. Accordingly, the color image can be recorded in a desirable state by the printer 2.

In order to prepare the upstream and downstream profiles U and D, the profile preparation system 100 executes the profile preparation program, stored in the hard disk 14, to attain a profile preparation process in a manner shown in FIG. 3.

The profile preparation process of FIG. 3 is started when a user of the profile preparation system 100 inputs, via the input unit 18, his/her desire to prepare the upstream profile U and the downstream profile D. The profile preparation process may be executed when the user desires to initially produce the upstream and downstream profiles. The profile preparation process may be executed also when the user desires to update the upstream and downstream profiles presently stored in the hard disk 14. Accordingly, the upstream and downstream profiles U and D can be updated when the characteristics of the printer 2 changes by the passage of time. The upstream and downstream profiles U and D can be updated also when the characteristics of the printer 2 changes for other reasons. For example, the upstream and downstream profiles U and D can be updated when the model of the printer 2 is changed, when the type of image recording medium used is changed, when the type of ink used is changed, when the setting of the resolution is changed, or when the setting of the printing speed is changed.

When the profile preparation process is started, first in S1, the CPU 11 stores data of the presently-existing upstream profile and data of the presently-existing downstream profile. The presently-existing profiles are those that have been prepared prior to the present profile preparation process and that have been stored in the hard disk 14. For example, if the present profile preparation process is executed for the first time after the system 100 is purchased, the presently-existing profiles are those that have been prepared before shipping of the system 100. On the other hand, if the present profile preparation process is performed after the profile preparation process has been performed one or more times after the system 100 is purchased, the presently-existing profiles are those that have been prepared by the user of the system 100 during a latest-performed profile preparation process. It is noted that if the present preparation process is executed to initially prepare the profiles, no profiles are presently existing.

During S1, data of the presently-existing upstream and downstream profiles, which are now stored in the hard disk 14, is copied and stored in the RAM 13. Alternatively, a set of back-up data may be created to store data of the presently-existing profiles, and be stored in some folder or the like. Thus, data of the presently-existing profiles is not erased or cancelled when the present profile preparation process is started. Even when the present profile preparation routine is terminated in the middle of the process as will be described later, data of the presently-existing profiles will be restored and can be used thereafter.

Next, in S2, in order to prepare the downstream profile D, the color printer 2 is controlled to print color patches on a recording medium. For example, nine cyan color patches are produced by cyan (C) ink as shown in FIG. 2(b) based on image data of predetermined nine tone levels of 0, 31, 63, 95, 127, 159, 191, 223, and 255. Similarly, nine magenta color patches are produced by magenta (M) ink based on image data of the predetermined nine tone levels of 0, 31, 63, 95, 127, 159, 191, 223, and 255. Nine yellow color patches are produced by yellow (Y) ink based on image data of the predetermined nine tone levels of 0, 31, 63, 95, 127, 159, 191, 223, and 255. Nine black color patches are produced by black (K) ink based on image data of the predetermined nine tone levels of 0, 31, 63, 95, 127, 159, 191, 223, and 255.

Next, in S3, the calorimeter 5 is controlled to measure the density level of the color patches.

Then, in S4, a downstream profile D is prepared based on the results of measurements taken in S3. For example, the downstream profile D is prepared so that input/output characteristic becomes linear for each color.

When the downstream profile D is prepared in S4, the program proceeds to S5.

In S5, the CPU 11 judges whether the present profile preparation processes should be terminated. This judgement is performed by controlling the CRT display 16 to display a message asking a user whether or not to terminate the present profile preparation processes. If the user inputs, via the input unit 18, his/her confirmation that the present profile preparation processes should be terminated (yes in S5), then the program proceeds to S16. In S16, data of the downstream profile D, which has just been prepared in S4, is restored into the initial state, which has been stored during S1, and the profile preparation processes are ended.

On the other hand, if the present profile preparation processes are to be continued (S5: NO), then in order to judge the properness of the presently-prepared downstream profile D and to prepare the upstream profile U, the color printer 2 is controlled in S6 to print color patches on the recording medium. At this time, for each color, image data for the predetermined nine tone levels of 0, 31, 63, 95, 127, 159, 191, 223, and 255 is first processed in the same manner as in the processes of S60 (FIG. 2(a)) by using the downstream profile D which has just been prepared in S4. Then, the printer 2 is controlled by the processed image data to print nine color patches. As a result, for each color, nine color patches are produced based on the processed image data.

Next, in S7, the calorimeter 5 is controlled to measure the density level of the color patches printed on the recording medium in S6.

Then in S8, the CPU 11 judges whether the prepared downstream profile D is suitable, based on the results of the measurements made in S7. The CPU 11 judges whether or not the prepared downstream profile D is suitable by confirming, for each color, whether the measured density levels of all the nine color patches increase from one to the next color patch in the expected monotone nondecreasing manner. In other words, the CPU 11 judges whether the measured density level of each color patch is higher than or equal to its preceding color patch. The CPU 11 determines that the prepared downstream profile is unsuitable when the measured density level of at least one color patch is smaller than its preceding color patch. The CPU 11 determines that the prepared downstream profile is suitable when the measured density level of each of all the color patches is higher than or equal to its preceding color patch.

Alternatively, the CPU 11 may judge in S8 whether or not the measured density level of each color patch is within a predetermined desirable range for the subject color patch. The CPU 11 determines that the prepared downstream profile is unsuitable when the measured density level of at least one color patch is out of its corresponding desirable range. The CPU 11 determines that the prepared downstream profile is suitable when the measured density level of each of all the color patches is within its corresponding desirable range.

If it is judged in S8 that the prepared downstream profile D is unsuitable (S8: unsuitable), then the program proceeds to S14, in which a notification is made that the downstream profile has been prepared improperly. For example, the CRT display 16 is controlled to display a message that the downstream profile is prepared improperly. Then in S15, the downstream profile D prepared in S4 is restored into the initial state, which has been stored in S1. Afterward, the routine returns to S2, whereupon the series of processes from preparation of the downstream profile D are repeated.

On the other hand, when it is judged that the prepared downstream profile D is suitable (S8: suitable), then the program proceeds to S9, in which the upstream profile U is prepared based on the results of measurements taken in S7.

Once the upstream profile U is prepared in S9, then the program proceeds to S10, in which it is again judged whether or not the present profile preparation processes should be terminated. This process is executed in the same manner as in S5. If the profile preparation processes should be terminated (S10: YES), then the program proceeds to S16, in which data of the presently-prepared downstream and upstream profiles U and D is restored into the initial state, which has been stored in S1. Afterward, the profile preparation processes are ended.

On the other hand, if the profile preparation processes are to be continued (S10: NO), then in S11 the color printer 2 is controlled to print test color patches on the recording medium. More specifically, for each color, image data for the predetermined nine tone values of 0, 31, 63, 95, 127, 159, 191, 223, and 255 is first processed in the same manner as in the process of S50 (FIG. 2(a)) by using the upstream profile U, which has just been prepared in S9, and is then processed in the same manner as in the process of S60 (FIG. 2(a)) by using the downstream profile D, which has just been prepared in S4. Color patches are printed based on the image data thus subjected to the processes according to both of the upstream and downstream profiles U and D. Thus, nine color patches are printed for each color.

Next, in S12, the calorimeter 5 is controlled to measure the density level of each test color patch printed on the recording medium. In S13, the CPU 11 judges whether the prepared upstream and downstream profiles U and D are suitable based on the results of the measurements taken in S12. The judgment made in S13 is performed in the same manner as described for S8. More specifically, the CPU 11 judges whether or not the prepared upstream and downstream profiles are suitable by confirming, for each color, whether or not the measured density levels of all the nine color patches increase from one to the next color patch in the expected monotone nondecreasing manner. The CPU 11 determines that one or both of the prepared upstream and downstream profiles are unsuitable when the measured density level of at least one color patch is smaller than its preceding color patch. The CPU 11 determines that both of the prepared upstream and downstream profiles are suitable when the measured density level of each of all the color patches is higher than or equal to its preceding color patch.

Alternatively, the CPU 11 may judge whether the measured density level of each color patch is within a predetermined desirable range for the subject color patch. The CPU 11 determines that one or both of the prepared upstream and downstream profiles are unsuitable when the measured density level of at least one color patch is out of its corresponding desirable range. The CPU 11 determines that both of the prepared upstream and downstream profiles are suitable when the measured density level of each of all the color patches is within its corresponding desirable range.

If it is judged in S13 that one or both of the upstream and downstream profiles is unsuitable (S13: unsuitable), then the program proceeds to S14. In S14, a notification is made that the one or both of the profiles has been prepared improperly. That is, the CRT 16 is controlled to display a message that one or both of the profiles has been prepared improperly. Then the program proceeds to S15, in which data of the downstream profile D prepared in S4 and data of the upstream profile U prepared in S9 is restored into the initial state, which has been stored in S1. Afterward, the routine returns to S2, whereupon the series of processes are repeated from preparation of the downstream profile D.

On the other hand, when it is judged that both of the upstream and downstream profiles are suitable (S13: suitable), then this series of profile preparation processes is ended. Then, data of the newly-produced upstream and downstream profiles U and D is written over data of the upstream and downstream profiles already stored in the hard disk 14. Data of the newly-produced upstream and downstream profiles may be stored together with indication data indicating that data of the newly-produced upstream and downstream profiles should be retrieved and used during an image recording process of FIG. 2(a) to be executed in the future and during the profile preparation process of FIG. 3 to be executed in the future.

It is noted that according to the present embodiment, the process of S13 is performed only after it is confirmed in S8 that the downstream profile is suitable. Accordingly, if it is judged in S13 that one or both of the upstream and downstream profiles is unsuitable, this normally means that the downstream profile is suitable, but the upstream profile is unsuitable. Accordingly, if it is judged in S13 that one or both of the upstream and downstream profiles is unsuitable, the program may proceed to S9, rather than to S2, after executing the processes of S14 and S15. In this case, the series of preparation processes only for the upstream profile will be repeated.

As described above, according to the profile preparation method of the present embodiment, the profile storing process (S1), the downstream profile preparation process (S2 to S4), the downstream profile judgment process (S6 to S8), the upstream profile preparation process (S6, S7, S9), and the profile judgment process (S11 to S13) are executed. When it is judged in the downstream profile judgment process that the downstream profile has been improperly prepared, or when it is judged in the profile judgment process that one or both of the upstream and downstream profiles has been improperly prepared, then the prepared profile(s) are returned, in S15, to the initial state of when stored in the profile storing process (S1). Afterward, the series of processes from preparing the downstream profile are again executed.

Next will be described one comparative method for preparing the upstream and downstream profiles U and D.

According to this comparative method, color patches are printed on a recording medium based on several sets of predetermined image data. Then, color of each color patch is measured using the calorimeter 5. Then, the downstream profile D is prepared based on the measurement results. Next, several sets of predetermined image data are processed in the same manner as in the subsequent processes of S60 based on the presently-prepared downstream profile D. Then, color patches are recorded based on the thus-processed image data. The color of these patches is measured using the colorimeter 5. Then, the upstream profile U is prepared based on the measurement results.

According to this comparative method, the downstream and upstream profiles D and U are prepared consecutively. Judgement of whether the downstream and upstream profiles are unsuitable is performed after both of the downstream and upstream profiles are prepared. That is, judgement of whether the downstream and upstream profiles are suitable is performed only when the image recording process of FIG. 2(a) is executed to actually use the profiles.

Thus, according to this comparative method, the upstream profile U is always prepared based on the downstream profile D, even when the downstream profile D is prepared inappropriate. In this case, the upstream profile U is also prepared improperly. Therefore, it is impossible to efficiently prepare the interrelated upstream and downstream profiles U and D. Judgement of properness of the profiles is not performed during the profile preparation processes. The only way to check whether profiles have been properly prepared is by actually outputting an image in the normal use mode of FIG. 2(a) after profile preparation processes are completely finished. If the profiles are unsuitable, then the profile preparation processes need to be performed again. This makes it troublesome to prepare proper profiles.

Contrarily, according to the present embodiment, the judgment about whether the prepared downstream profile is suitable or not is made after the downstream profile is prepared, but before the upstream profile is prepared. When the downstream profile is improperly prepared, then the downstream profile is promptly prepared again, without preparing the upstream profile, which is to be influenced by the downstream profile. Therefore, even if the downstream profile is improperly prepared, the profiles can be more efficiently prepared than the comparative manner, wherein the upstream profile is prepared whenever the downstream profile is prepared.

The profile preparation system 100 is designed so that after the upstream profile is prepared, it can be judged whether the prepared upstream and downstream profiles are properly prepared. With this configuration, if at least one of the upstream and downstream profiles has not been properly prepared, then the profile preparation processes will be promptly restarted. The upstream and downstream profiles can be prepared more efficiently, with less trouble, than when using the comparative profile preparation method, wherein whether a profile is properly prepared can only be judged by actually outputting an image using a normal usage mode of FIG. 2(a).

Also, because data of the upstream and downstream profiles, which exist before the profiles are newly prepared, are stored in S1, even if the profiles are not properly prepared, or if profile preparation processes are terminated in the middle of the processes, the profiles can be promptly returned to the initial condition, so that it is ensured that images can be recorded using the initial condition profiles.

The profile preparation method of the present embodiment will be described below in greater detail with reference to a specific example of the upstream profile U and a specific example of the downstream profile D.

The specific example of the upstream profile U and the specific example of the downstream profile D are used in the image recording process of FIG. 5. It is noted that the image recording process of FIG. 5 is executed also by the profile preparation system 100 of the present embodiment.

During the image recording process of FIG. 5, when input color data (Ci, Mi, Yi, Ki) is received from an image preparation application or the like, the input image data (Ci, Mi, Yi, Ki) is color-corrected in S100 into color-corrected color data (Ci', Mi', Yi', Ki') by using a color-correction table T1.

Then, in S200, the cyan component Ci' of the color-corrected color data (Ci', Mi', Yi', Ki') is tone-corrected into color-and-tone-corrected cyan data Ci'' by using a tone-correction table T2c for cyan color. The magenta component Mi' is tone-corrected into color-and-tone-corrected magenta data Mi'' by using a tone-correction table T2m for magenta color. The yellow component Yi' is tone-corrected into color-and-tone-corrected yellow data Yi'' by using a tone-correction table T2y for yellow color. The black component Ki' is tone-corrected into color-and-tone-corrected black data Ki'' by using a tone-correction table T2k for yellow color.

Then, in S300, the color-and-tone-corrected cyan data Ci'' is converted into light cyan ink data Cl and normal cyan ink data Cn by using a cyan conversion table T3c. The color-and-tone-corrected magenta data Mi'' is converted into light magenta ink data Ml and normal magenta ink data Mn by using a magenta conversion table T3m.

Then, in S400, the light cyan ink data Cl is tone-corrected into tone-corrected light cyan ink data Cl' by using a tone-correction table T4cl for light cyan ink. The normal cyan ink data Cn is tone-corrected into tone-corrected normal cyan ink data Cn' by using a tone-correction table T4cn for normal cyan ink. The light magenta ink data Ml is tone-corrected into tone-corrected light magenta ink data Ml' by using a tone-correction table T4ml for light magenta ink. The normal magenta ink data Mn is tone-corrected into tone-corrected normal magenta ink data Mn by using a tone-correction table T4nm for normal magenta ink.

Then, in S500, the tone-corrected ink data Cl', Cn', Ml', Mn' for light cyan, normal cyan, light magenta, and normal magenta, and the color-and-tone-corrected data Yi'' and Ki'' for yellow and black are binarized into a set of binarized color data (Clo, Cno, Mlo, Mno, Yo, Ko) in a well-known manner, such as described in U.S. Pat. No. 5,045,952.

Then, in S600, the binarized color data (Clo, Cno, Mlo, Mno, Yo, Ko) is outputted to the printer 2, where a desired color image is printed based on the binarized color data (Clo, Cno, Mlo, Mno, Yo, Ko).

In this example, the print unit 21 is of a type that forms images on a recording medium by ejecting six inks of light cyan (Cl), normal cyan (Cn), light magenta (Ml), normal magenta (Mn), yellow (Y), and black (K) based on a set of binary color data (Clo, Cno, Mlo, Mno, Yo, Ko) that is received from the personal computer 1. It is noted that the normal cyan ink has cyan color denser than the light cyan ink. Similarly, the normal magenta ink has magenta color denser than the light magenta ink. The print unit 21 is configured to record multi-tone color images, having density levels of 256 different tones for each of four colors of cyan, magenta, yellow, and black, by selectively ejecting dots of the six inks according to the binary color data (Clo, Cno, Mlo, Mno, Yo, Ko).

It is noted that the tone-correction tables T2c, T2m, T2y, and T2k are the example of the upstream profile U. The tone-correction tables T4cl, T4cn, T4ml, and T4nm are the example of the downstream profile D. The tables T1, T2c, T2m, T2y, and T2k, T3c and T3m, and T4cl, T4cn, T4ml, and T4nm are stored in the hard disk 14.

The color correction table T1 is a look up table used to correct, in S100, input color data (Ci, Mi, Yi, Ki) in order to reproduce colors faithfully by taking into account how respective colors of cyan, magenta, yellow, and black influence one another. As shown in FIG. 6, the color correction table T1 includes a plurality of sets of color data (C, M, Y, K), which are possibly inputtable to the color-correction process of S100. The color correction table T1 includes, in correspondence with each set of color data (C, M, Y, K), a set of color-corrected color data (C', M', Y', K'), which should be outputted from the color-correction process of S100 in response to the input of the subject set of color data (C, M, Y, K).

More specifically, the color correction table T1 includes 6,561 (=9.sup.4) sets of color data (C, M, Y, K), wherein C=0, 31, 63, 95, 127, 159, 191, 223, and 255, M=0, 31, 63, 95, 127, 159, 191, 223, and 255, Y=0, 31, 63, 95, 127, 159, 191, 223, and 255, and K=0, 31, 63, 95, 127, 159, 191, 223, and 255. In association with each set of color data (C, M, Y, K), the table T1 includes one set of color-corrected color data (C', M', Y', K') that should be outputted from the process of S100 to reproduce the corresponding color data (C, M, Y, K). Thus, the co