We claim:
1. A method for forming a color conversion table including plural data which, according to the correlation between a first color space and a second color space as defined by a prescribed number of previously acquired sample data, defines the correlation between the first color space and the second color space, the method comprising:
a step of setting, in the first color space, target coordinates with respect to which the correlation is defined;
a step of setting, in the second color space, conversion object coordinates;
a step of converting the conversion object coordinates into corresponding coordinates in the first color space according to the sample data;
a step of carrying out a trial process involving the step of setting conversion object coordinates and the step of converting them so as to decrease the difference between the corresponding coordinates in the first color space as obtained by the conversion step and the target coordinates; and
a step of generating color conversion table data which defines the correlation between the conversion object coordinates in the second color space and the target coordinates when the difference becomes smaller than a prescribed threshold at the trial step.
2. A method for forming a color conversion table including plural data which, according to the correlation between a first color space and a second color space as defined by a prescribed number of previously acquired sample data, defines the correlation between the first color space and the second color space, the method comprising:
a step of acquiring sample data which make up a virtually cubic lattice in the second color space with the corresponding lattice points in the first color space making up a non-cube;
a step of setting, in the first color space, target coordinates with respect to which the correlation is defined;
a step of setting, in the second color space, conversion object coordinates;
a step of converting the conversion object coordinates into corresponding coordinates in the first color space according to the sample data;
a step of carrying out a trial process involving the step of setting conversion object coordinates and the step of converting them so as to decrease the difference between the corresponding coordinates in the first color space as obtained by the conversion step and the target coordinates; and
a step of generating color conversion table data which defines the correlation between the conversion object coordinates in the second color space and the target coordinates when the difference becomes smaller than a prescribed threshold at the trial step.
3. A method for forming a color conversion table including plural data which, according to the correlation between a first color space and a second color space as defined by a prescribed number of previously acquired sample data, defines the correlation between desired coordinates in the first color space and coordinates in the second color space,
wherein the step of converting coordinates in the second color space into coordinates in the first color space according to the previously defined correlation can be carried out; and
wherein coordinates in the first color space corresponding to the coordinates in the second color space are calculated by the conversion step; and the difference between the calculated coordinates and the coordinates in the first color space is fed back; then the process of setting next coordinates in the second color space is repeated to find coordinates in the second color space which correspond to the desired coordinates in the first color space and include it in the color conversion table data.
4. The method for forming a color conversion table as claimed in claim 1, wherein the first color space is a uniform color space and the second color space consists of components corresponding to three colors to be used in an image device.
5. The method for forming a color conversion table as claimed in claim 1, wherein the second color space consists of components corresponding to three colors to be used in an image device, and sample data which defines the correlation between the first color space and the second color space is obtained by measuring the colors outputted by the image device with a prescribed calorimeter.
6. The method for forming a color conversion table as claimed in claim 1, wherein, at the step of setting target coordinates, coordinates in a third color space are converted into coordinates in the first color space in accordance with a prescribed formula and the resulting coordinates are treated as target coordinates.
7. The method for forming a color conversion table as claimed in claim 6, wherein the third color space consists of components corresponding to three colors to be used in an image device.
8. The method for forming a color conversion table as claimed in claim 6, wherein, at the step of setting target coordinates, target coordinates are determined by mapping the coordinates in the first color space obtained by conversion of coordinates in the third color space, in a specified area in the first color space, within the color gamut of the image device which uses the second color space.
9. The method for forming a color conversion table as claimed in claim 1, wherein, in the first trial at the step of setting target coordinates, the same initial coordinates are set for any target coordinates.
10. The method for forming a color conversion table as claimed in claim 1, wherein the first color space is almost symmetric with respect to a specific axis and, in the first trial of the step of setting target coordinates, coordinates in the vicinity of the specific axis are made the initial coordinates to be converted.
11. The method for forming a color conversion table as claimed in claim 1, wherein at the conversion step, conversion object coordinates in the second color space are converted into coordinates in the first color space using a spline interpolation function determined by the sample data.
12. The method for forming a color conversion table as claimed in claim 1, wherein at the trial step, if the difference in the first color space does not become smaller than a prescribed threshold, the trial process is once stopped after a prescribed number of trials made and the conversion method is changed and then the trial process is resumed.
13. The method for forming a color conversion table as claimed in claim 1, wherein at the trial step, if the difference in the first color space does not become smaller than a prescribed threshold, the trial process is once stopped after a prescribed number of trials made, the initial coordinates to be converted in the first trial are revised and the trial process is resumed.
14. The method for forming a color conversion table as claimed in claim 13, wherein the first color space is virtually symmetric with respect to a specific axis and at the step, after the trial process is once stopped, coordinates which are away from the initial coordinates by a given distance along the specific axis are defined as new initial coordinates and the trial process is resumed.
15. A method for forming a color conversion table which generates color conversion table data where: specific CMY coordinates are given; uniform color space coordinates are obtained as data in a uniform color space such as an Luv color space by measuring color samples outputted by a printing apparatus with a colorimeter; and plural sample data which define the correlation between the CMY color space and the uniform color space using the uniform color space coordinates and the CMY coordinates are given, the color conversion table including plural data defining the correlation between the RGB color space to be used by a display and the CMY color space according to the sample data, the method comprising:
a step of setting corresponding uniform color space coordinates by converting plural coordinates making up a virtually cubic lattice in the RGB color space in accordance with a prescribed formula;
a step of setting initial CMY coordinates in the CMY color space;
a step of converting the initial CMY coordinates into uniform color space coordinates by interpolation according to the correlation defined by the sample data;
a step of calculating the difference between the uniform color space coordinates obtained by the step of converting initial CMY coordinates and the target uniform color space coordinates
a step of repeating a trial in which the CMY coordinates are determined so as to decrease the difference in the uniform color space and the CMY coordinates thus determined are again converted into uniform color space coordinates by interpolation as mentioned above and the difference is calculated again; and
a step of generating color conversion table data for converting image data expressed by the RGB color space to be used by the display, into image data expressed by a CMY color space to be used on a printing apparatus, by correlating the CMY coordinates when the difference becomes smaller than a prescribed threshold at the trial step, with the target uniform color space coordinates and correlating the RGB coordinates as the source of the target coordinates with the CMY coordinates.
16. An apparatus for forming a color conversion table including plural data which, according to the correlation between a first color space and a second color space as defined by a prescribed number of previously acquired sample data, defines the correlation between the first color space and the second color space, the apparatus comprising:
a unit for setting, in the first color space, target coordinates with respect to which the correlation is defined;
a unit for setting, in the second color space, conversion object coordinates;
a unit for converting the conversion object coordinates into corresponding coordinates in the first color space according to the sample data;
trial unit for putting the unit for setting conversion object coordinates and the unit for converting them into execution so as to decrease the difference between the corresponding coordinates in the first color space as obtained by the conversion unit and the target coordinates; and
a unit for generating color conversion table data which defines the correlation between the conversion object coordinates in the second color space and the target coordinates when the difference becomes smaller than a prescribed threshold through the trial unit.
17. An apparatus for forming a color conversion table including plural data which, according to the correlation between a first color space and a second color space as defined by a prescribed number of previously acquired sample data, defines the correlation between the first color space and the second color space, the method comprising:
a unit for acquiring sample data which make up a virtually cubic lattice in the second color space with the corresponding lattice points in the first color space making up a non-cube;
a unit for setting, in the first color space, target coordinates with respect to which the correlation is defined;
a unit for setting, in the second color space, conversion object coordinates;
a unit for converting the conversion object coordinates into corresponding coordinates in the first color space according to the sample data;
trial unit for putting the unit for setting conversion object coordinates and the unit for converting them into execution so as to decrease the difference between the corresponding coordinates in the first color space as obtained by the conversion unit and the target coordinates; and
generating color conversion table data which defines the correlation between the conversion object coordinates in the second color space and the target coordinates when the difference becomes smaller than a prescribed threshold through the trial unit.
18. An apparatus for forming a color conversion table which forms a color conversion table including plural data which, according to the correlation between a first color space and a second color space as defined by a prescribed number of previously acquired sample data, defines the correlation between desired coordinates in the first color space and coordinates in the second color space,
wherein coordinates in the second color space can be converted into coordinates in the first color space according to the previously defined correlation,
the apparatus comprising:
a unit for calculating coordinates in the first color space corresponding to the coordinates in the second color space by the above conversion process;
trial unit for feeding back the difference between the calculated coordinates and desired coordinates in the first color space and repeating the process of setting next coordinates in the second color space; and
a unit for working out coordinates in the second color space which correspond to the desired coordinates in the first color space and including them in the color conversion table data.
19. An apparatus for forming a color conversion table which generates color conversion table data where: specific CMY coordinates are given; uniform color space coordinates are obtained as data in a uniform color space such as an Luv color space by measuring color samples outputted by a printing apparatus with a calorimeter; and plural sample data which define the correlation between the CMY color space and the uniform color space using the uniform color space coordinates and the CMY coordinates are given, the color conversion table including plural data defining the correlation between the RGB color space to be used by a display and the CMY color space according to the sample data, the apparatus comprising:
a unit for setting corresponding uniform color space coordinates by converting plural coordinates making up a virtually cubic lattice in the RGB color space in accordance with a prescribed formula;
a unit for setting initial CMY coordinates in the CMY color space;
a unit for converting the initial CMY coordinates into uniform color space coordinates by interpolation according to the correlation defined by the sample data;
a unit for calculating the difference between the uniform color space coordinates obtained by the unit for converting initial CMY coordinates and the target uniform color space coordinates;
a unit for repeating a trial in which the CMY coordinates are determined so as to decrease the difference in the uniform color space and the CMY coordinates thus determined are again converted into uniform color space coordinates by interpolation as mentioned above and the difference is calculated again; and
a unit for generating color conversion table data for converting image data expressed by the RGB color space to be used by the display, into image data expressed by a CMY color space to be used on a printing apparatus, by correlating CMY coordinates when the difference becomes smaller than a prescribed threshold through the trial unit, with the target uniform color space coordinates and correlating the RGB coordinates as the source of the target coordinates with the CMY coordinates.
20. A program for forming a color conversion table including plural data which, according to the correlation between a first color space and a second color space as defined by a prescribed number of previously acquired sampled at a, defines the correlation between the first color space and the second color space,
wherein the computer performs:
a function of setting, in the first color space, target coordinates with respect to which the correlation is defined;
a function of setting, in the second color space, conversion object coordinates;
converting the conversion object coordinates into corresponding coordinates in the first color space according to the sample data;
a trial function of putting the function of setting conversion object coordinates and the conversion function into execution so as to decrease the difference between the corresponding coordinates in the first color space as obtained by the conversion function and the target coordinates; and
a function of generating color conversion table data which defines the correlation between the conversion object coordinates in the second color space and the target coordinates when the difference becomes smaller than a prescribed threshold through the trial function.
21. A program for forming a color conversion table including plural data which, according to the correlation between a first color space and a second color space as defined by a prescribed number of previously acquired sampled at a, defines the correlation between the first color space and the second color space,
wherein the computer performs:
a function of acquiring sample data which make up a virtually cubic lattice in the second color space with the corresponding lattice points in the first color space making up a non-cube;
a function of setting, in the first color space, target coordinates with respect to which the correlation is defined;
a function of setting, in the second color space, conversion object coordinates to be converted;
a function of converting the conversion object coordinates into corresponding coordinates in the first color space according to the sample data;
a trial function of putting the function of setting conversion object coordinates and the function of converting them into execution so as to decrease the difference between the corresponding coordinates in the first color space as obtained by the conversion step and the target coordinates; and
a function of generating color conversion table data which defines the correlation between the conversion object coordinates in the second color space and the target coordinates when the difference becomes smaller than a prescribed threshold through the trial function.
22. A program for forming a color conversion table including plural data which, according to the correlation between a first color space and a second color space as defined by a prescribed number of previously acquired sampled at a, defines the correlation between desired coordinates in the first color space and coordinates in the second color space,
wherein coordinates in the second color space can be converted into coordinates in the first color space according to the previously defined correlation can be carried out; and
wherein the computer performs:
a function of repeating the process of setting next coordinates in the second color space by calculating coordinates in the first color space corresponding to given coordinates in the second color space and feeding back the difference between the calculated coordinates and the desired coordinates in the first color space; and
a function of generating color conversion table data by calculating coordinates in the second color space which correspond to the desired coordinates in the first color space and including it in the color conversion table data.
23. A program for forming a color conversion table which generates color conversion table data where: specific CMY coordinates are given; uniform color space coordinates are obtained as data in a uniform color space such as an Luv color space by measuring color samples outputted by a printing apparatus with a calorimeter; and plural sample data which define the correlation between the CMY color space and the uniform color space using the uniform color space coordinates and the CMY coordinates are given, the color conversion table including plural data defining the correlation between the RGB color space to be used by a display and the CMY color space according to the sample data,
wherein a computer performs:
a function of setting corresponding uniform color space coordinates by converting plural coordinates making up a virtually cubic lattice in the RGB color space in accordance with a prescribed formula;
a function of setting initial CMY coordinates in the CMY color space;
a function of converting the initial CMY coordinates into uniform color space coordinates by interpolation according to the correlation defined by the sample data;
a function of calculating the difference between the uniform color space coordinates obtained by the function of converting initial CMY coordinates and the target uniform color space coordinates;
a function of repeating a trial in which the CMY coordinates are determined so as to decrease the difference in the uniform color space and the CMY coordinates thus determined are again converted into uniform color space coordinates by interpolation as mentioned above and the difference is calculated again; and
a function of generating color conversion table data for converting image data expressed by the RGB color space to be used by the display, into image data expressed by a CMY color space to be used on a printing apparatus, by correlating CMY coordinates when the difference becomes smaller than a prescribed threshold through the trial function, with the target uniform color space coordinates and correlating the RGB coordinates as the source of the target coordinates with the CMY coordinates.
24. A printing apparatus comprising:
a head having a nozzle which receives ink from ink-filled cartridges of plural colors and ejects the ink;
image data acquisition unit for acquiring image data which expresses colors of pixels in a dot matrix by coordinate values in a third color space;
color conversion unit for converting the image data into coordinates in a second color space referring to first color conversion table data stored in a prescribed recording medium;
printing data generation unit for generating printing data which specifies the recording density of ink to be ejected from each nozzle of the head according to image data after the color conversion; and
head drive control unit for receiving the printing data through a prescribed interface and driving the head according to the printing data,
the first color conversion table data being generated by:
a step of previously acquiring a prescribed number of sample data which defines the correlation between a first color space and a second color space;
a step of setting target coordinates in a first color space by converting coordinates in a third color space into coordinates in a first color space in accordance with a prescribed formula;
a step of setting conversion object coordinates in the second color space;
a step of converting the conversion object coordinates into corresponding coordinates in a first color space according to the sample data;
a step of repeating the step of setting conversion object coordinates and the conversion step so as to decrease the difference between the corresponding coordinates in the first color space obtained by the conversion step and the target coordinates;
a step of generating second color conversion table data by correlating the conversion object coordinates in the second color space with the target coordinates when the difference becomes smaller than a prescribed threshold at the trial step; and
a step of generating first color conversion table data by correlating the coordinates in the third color space as the source of the target coordinates in the first color space defined by the second color conversion table, with the coordinates in the second color space defined by the second color conversion table.
25. A printing apparatus comprising:
a head having a nozzle which receives ink from ink-filled cartridges of plural colors and ejects the ink;
image data acquisition unit for acquiring image data which expresses colors of pixels in a dot matrix by coordinate values in a third color space;
color conversion unit for converting the image data into coordinates in a second color space referring to first color conversion table data stored in a prescribed recording medium;
printing data generation unit for generating printing data which specifies the recording density of ink to be ejected from each nozzle of the head according to image data after the color conversion; and
head drive control unit for receiving the printing data through a prescribed interface and driving the head according to the printing data,
the first color conversion table data being generated by:
a step of previously acquiring a prescribed number of sample data which defines the correlation between these color spaces, with lattice points making up a virtually cubic lattice in a second color space and corresponding lattice points in a first color space making up a non-cubic lattice;
a step of setting target coordinates in a first color space by converting coordinates in a third color space into coordinates in a first color space in accordance with a prescribed formula;
a step of setting conversion object coordinates in the second color space (step of setting conversion object coordinates);
a step of converting the conversion object coordinates into corresponding coordinates in a first color space according to the sample data;
a step of repeating the step of setting conversion object coordinates and the conversion step so as to decrease the difference between the corresponding coordinates in the first color space obtained by the conversion step and the target coordinates;
a step of generating second color conversion table data by correlating the conversion object coordinates in the second color space with the target coordinates when the difference becomes smaller than a prescribed threshold at the trial step; and
a step of generating first color conversion table data by correlating the coordinates in the third color space as the source of the target coordinates in the first color space defined by the second color conversion table, with the coordinates in the second color space defined by the second color conversion table.
26. A printing apparatus comprising:
a head having a nozzle which receives ink from ink-filled cartridges of plural colors and ejects the ink;
a unit for acquiring image data which expresses colors of pixels in a dot matrix by coordinate values in a third color space;
a unit for converting the image data into coordinates in a second color space referring to first color conversion table data stored in a prescribed recording medium;
a unit for generating printing data which specifies the recording density of ink to be ejected from each nozzle of the head according to image data after the color conversion; and
head drive control unit for receiving the printing data through a prescribed interface and driving the head according to the printing data,
the first color conversion table data being generated by:
a step of previously acquiring a prescribed number of sample data which defines the correlation between a first color space and a second color space;
a step of converting coordinates in the second color space into coordinates in a first color space according to the correlation defined by the sample data;
a step of generating second color conversion table data by calculating coordinates in the first color space corresponding to the coordinates in the second color space by the conversion step, repeating the process of feeding back the difference between the calculated coordinates and desired coordinates in the first color space to set next coordinates in the second color space, and calculating coordinates in the second color space corresponding to the desired coordinates in the first color space; and
a step of generating first color conversion table data by converting target coordinates in the first color space as defined by the second color conversion table into coordinates in the third color space in accordance with a prescribed formula and correlating the coordinates in the third color space as obtained by the conversion with the coordinates in the second color space as defined by the second color conversion table.
27. A printing apparatus comprising:
a head having a nozzle which receives ink from ink-filled cartridges of plural colors and ejects the ink;
a unit for acquiring image data which expresses colors of pixels in a dot matrix by coordinates in an RGB color space to be used by a display;
a unit for converting the image data which expresses colors by coordinates in the RGB color space, into image data which expresses colors by coordinates in a CMY color space to be used by a printing apparatus, referring to color conversion table data stored in a prescribed recording medium;
a unit for generating printing data which specifies the recording density of ink to be ejected from each nozzle of the head according to image data after the color conversion; and
head drive control unit for receiving the printing data through a prescribed interface and driving the head according to the printing data,
the color conversion table data being generated by:
a step of acquiring plural sample data which define the correlation between a CMY color space and a uniform color space, with specific CMY coordinates being given, using uniform color space coordinates obtained as data in a uniform color space such as an Luv color space and the CMY coordinates by measuring color samples outputted by a printing apparatus with a calorimeter;
a step of setting corresponding uniform color space coordinates by converting plural coordinates making up a virtually cubic lattice in the RGB color space in accordance with a prescribed formula;
a step of setting initial CMY coordinates in the CMY color space;
a step of converting the initial CMY coordinates into uniform color space coordinates by interpolation according to the correlation defined by the sample data;
a step of calculating the difference between the uniform color space coordinates obtained by the step of converting initial CMY coordinates and the target uniform color space coordinates
a step of repeating a trial in which the CMY coordinates are determined so as to decrease the difference in the uniform color space and the CMY coordinates thus determined are again converted into uniform color space coordinates by interpolation as mentioned above and the difference is calculated again; and
a step of generating color conversion table data by correlating CMY coordinates when the difference becomes smaller than a prescribed threshold at the trial step, with the target uniform color space coordinates and correlating the RGB coordinates as the source of the target coordinates with the CMY coordinates.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A system comprising: a database operative to maintain a social graph; a leader cache layer comprising one or more leader cache clusters, and a follower cache layer comprising one or more follower cache clusters, wherein the leader cache layer is operative to:
communicate social graph information between the follower cache cluster and the database, wherein each follower cache cluster maintains at least a portion of the social graph;
receive a request from one of the follower cache clusters to store social graph information in the database;
update the database storing the social graph responsive to the request; and
update one or more of the follower cache clusters storing the portion of the social graph associated with the request.
2. The system of claim 1, wherein the social graph comprises a plurality of graph nodes and a plurality of graph edges connecting the graph nodes, each graph edge connecting two graph nodes indicating an association between the two graph nodes.
3. The system of claim 2, wherein each graph node of the social graph is associated with a unique identifier.
4. The system of claim 3, wherein each unique identifier is stored with its respective graph node in one or more of the one or more follower cache cluster or one or more leader cache clusters.
5. The system of claim 1, wherein the one or more leader cache clusters includes a plug-in operative to interoperate with the database.
6. The system of claim 5, wherein the plug-in performs one or more translation operations.
7. The system of claim 6, wherein the social graph comprises a plurality of graph nodes and a plurality of graph edges connecting the graph nodes, and wherein the one or more translation operations comprises translating the graph nodes and graph edges stored in the one or more follower cache clusters to one or more queries to be sent to the database.
8. The system of claim 1, wherein the database utilizes CASSANDRA.
9. The system of claim 1, wherein each of the one or more leader cache clusters maintains a cache consistency between each of the one or more follower cache clusters and the database.
10. The system of claim 1, wherein each of the one or more leader cache clusters maintains a cache consistency between each of the one or more follower cache clusters and each of the leader cache clusters.
11. The system of claim 1, wherein the one or more leader cache clusters are further operative to update the database with the social graph information cached in the one or more leader cache clusters.
12. The system of claim 1, wherein the one or more leader cache clusters and one or more follower cache clusters operate as a caching layer between a client server and the database.
13. The system of claim 1, wherein each follower cache cluster comprises a plurality of follower cache nodes.
14. The system of claim 11, wherein the follower cache nodes of a particular follower cache cluster may communicate only with the follower caches nodes in the particular cache cluster and the one or more leader cache clusters.
15. The system of claim 1, wherein each leader cache cluster comprises a plurality of leader cache nodes.
16. The system of claim 1, wherein the social graph maintained by the database is stored as a distributed graph across the one or more follower cache clusters and the one or more leader cache clusters.
17. The system of claim 1, wherein the social graph information stored in the database is stored relationally.
18. The system of claim 1, wherein the one or more follower cache clusters and the one or more leader cache clusters are operative to store social graph information in one or more data shards of the respective cache cluster.
19. A non-transitory storage medium of a system storing computer-readable instructions, the system comprising a database operative to maintain a social graph; a leader cache layer comprising one or more leader cache clusters, and a follower cache layer comprising one or more follower cache clusters, wherein the instruction, when executed, are operative to cause the leader cache layer to:
communicate social graph information between the follower cache cluster and the database, wherein each follower cache cluster maintains at least a portion of the social graph;
receive a request from one of the follower cache clusters to store social graph information in the database;
update the database storing the social graph responsive to the request; and
update one or more of the follower cache clusters storing the portion of the social graph associated with the request.
20. A method by a leader cache layer of a system, the system comprising: a database operative to maintain a social graph; the leader cache layer comprising one or more leader cache clusters, and a follower cache layer comprising one or more follower cache clusters, the method by the leader cache layer comprising:
communicating social graph information between the follower cache cluster and the database, wherein each follower cache cluster maintains at least a portion of the social graph;
receiving a request from one of the follower cache clusters to store social graph information in the database;
updating the database storing the social graph responsive to the request; and
updating one or more of the follower cache clusters storing the portion of the social graph associated with the request.