Processing

Please wait...

Settings

Settings

Goto Application

1. WO2001075802 - COLOR ACCURACY ACROSS A COMPUTER NETWORK

Note: Text based on automatic Optical Character Recognition processes. Please use the PDF version for legal matters

[ EN ]

CLAIMS:

1. A method comprising:

obtaining information characterizing the color response of a display device associated with a client residing on a computer network;

modifying a color image based on the information to improve the accuracy of the color image when displayed on the display device; and

delivering the modified color image to the client via the computer network for display on the display device.

2. The method of claim 1, further comprising obtaining the information by guiding the client through a color profiling process that profiles the color response of the display device.

3. The method of claim 2, wherein the color profiling process includes: estimating the black point of the display device;

estimating a coarse gamma for the display device;

estimating a fine gamma for the display device based in part on the coarse gamma;

estimating the gray balance of the display device; and

generating a color profile based on the black point, the coarse gamma, the fine gamma, and the gray balance.

4. The method of claim 3, wherein estimating the black point of the display device includes:

displaying a first range of gray elements on the display device;

setting the contrast of the display device to maximum;

setting the brightness of the display device to maximum;

reducing the brightness of the display device until the darkest of the gray elements is barely visible;

selecting the gray element that is barely visible.

5. The method of claim 4, wherein:

estimating the coarse gamma includes:

displaying a second range of gray elements with a dithered

approximately 50% gray background,

selecting the gray element that appears to most closely blend with the background, and

estimating a single coarse gamma for the red, green, and blue channels of the display device based on the gray level of the selected gray element, and

estimating the fine gamma includes:

displaying the selected gray element within a third range of gray elements with the dithered background, wherein the gray levels of the third range of gray elements are more closely spaced than the gray levels in the second range of gray elements and substantially centered about the gray level of the selected gray element;

selecting the gray element in the third range of gray elements that appears to most closely blend with the dithered background; and

estimating a single fine gamma for the red, green, and blue channels of (he display device based on the gray level of the selected gray element in the third range of gray elements.

6. The method of claim 5, wherein estimating the gray balance includes: displaying the selected gray element from the third range of gray elements among a fourth range of red-, green-, and blue-shifted gray elements with the background;

selecting the gray element in the fourth range of gray elements that appears to most closely blend with the background; and

estimating individual gammas for the red, green, and blue channels of the display device based on the gray level of the selected gray element in the fourth range of gray elements.

7. The method of claim 2, wherein the color profiling process includes: displaying a dark element and a darker element on the display device;

setting the contrast and brightness of the display to maximum;

reducing the brightness until the darker element is not visible;

reducing the brightness until the dark element is barely visible;

displaying a first range of gray elements with a dithered approximately 50% gray background;

selecting the gray element in the first range that appears to most closely blend with the dithered background; and

estimating the gamma of the display device based on the gray level of the selected gray element.

8. The method of claim 7, wherein the color profiling process further includes:

display ranges of gray elements for the red, green, and blue color channels of the display device with dithered approximately 50% gray red, green and blue backgrounds;

selecting the red, green, and blue gray elements that appear to most closely blend with the respective backgrounds; and

estimating individual gammas for the red, green, and blue color channels based on the selected red, green, and blue gray elements.

9. The method of claim 2, further comprising:

guiding the client through the color profiling process by delivering a series of instructional web pages to the client;

obtaining the information by generating a web cookie based on results of the color profiling process; and

transmitting the web cookie to a remote server in the computer network, wherein the remote server modifies the color image based on the information, and delivers the modified color image to the client.

10. The method of claim 1 , further comprising:

transmitting a web page from a web server to the client, wherein the web page includes an image tag identifying the color image on a color image server residing on the computer network;

transmitting the information as part of a web cookie to the color image server. wherein the color image server modifies the color image based on the information; and

transmitting the color image from the color image server to the client.

1 1. The method of claim 1 , further comprising:

transmitting a first web page from a color profile server to the client, the web page guiding the client through a color profiling process to obtain the information; transmitting a second web page from a web server to the client, wherein the web page includes an image tag identifying the color image on a color image server residing on the network;

transmitting the information as part of a web cookie to the color image server. wherein the color image server modifies the color image based on the information; and

transmitting the color image form the color image server to the client.

12. A system comprising:

a web server residing on a computer network, the web server transmitting web pages to remote clients residing on the computer network;

a color image server residing on the computer network, the color image server transmitting color images referenced by the web pages to the clients for display on display devices associated with the clients;

a color profile server residing on the computer network, the color profile server guiding the clients through a color profiling process to obtain information characterizing the color responses of the display devices associated with the clients; and

one or more color correction modules that modify the color images transmitted by the color image server based on the information to improve the accuracy of the color images when displayed on the respective display device.

obtaining information characterizing the color response of a display device associated with a client residing on a computer network;

modifying a color image based on the information to improve the accuracy of the color image when displayed on the display device; and

delivering the modified color image to the client via the computer network for display on the display device.

13. The system of claim 12, wherein the one or more color correction modules include a plurality of color correction modules, each of the color correction modules being resident with one of the color image servers on the network.

14. The system of claim 12, wherein the color profile server delivers a series of instructional web pages to the client that guide a user associated with the client through the color profiling process, and wherein the color profiling process includes:

estimating the black point of each of the display devices;

estimating a coarse gamma for each of the display devices;

estimating a fine gamma for each of the display devices based in part on the coarse gamma;

estimating the gray balance of each of the display devices; and

generating a color profile based on the black point, the coarse gamma, the fine gamma, and the gray balance.

15. The system of claim 12, wherein estimating the black point of each of the display devices includes:

displaying a first range of gray elements on each of the display devices;

setting the contrast of each of the display devices to maximum;

setting the brightness of each of the display devices to maximum;

reducing the brightness of each of the display devices until the darkest of the gray elements is barely visible;

selecting the gray element that is barely visible.

16. The system of claim 15, wherein:

estimating the coarse gamma includes:

displaying a second range of gray elements with a dithered

approximately 50% gray background;

selecting the gray element that appears to most closely blend with the background, and

estimating a single coarse gamma for the red, green, and blue channels of each of the display devices based on the gray level of the selected gray element, and

estimating the fine gamma includes:

displaying the selected gray element within a third range of gray elements with the background, wherein the gray levels of the third range of gray elements are more closely spaced than the gray levels in the second range of gray elements and substantially centered about the gray level of the selected gray element;

selecting the gray clement in the third range of gray elements that appears to most closely blend with the background; and

estimating a single fine gamma for the red, green, and blue channels of each of the display devices based on the gray level of the selected gray element in the third range of gray elements.

17. The system of claim 16, wherein estimating the gray balance includes: displaying the selected gray element from the third range of gray elements among a fourth range of red-, green-, and blue-shifted gray elements with the background;

selecting the gray element in the fourth range of gray elements that appears to most closely blend with the background; and

estimating individual gammas for the red, green, and blue channels of each of the display devices based on the gray level of the selected gray element in the fourth range of gray elements.

18. The system of claim 12, wherein the color profiling process includes:

displaying a dark element and a darker element on each of the display devices; setting the contrast and brightness of the display to maximum;

reducing the brightness until the darker element is not visible;

reducing the brightness until the dark element is barely visible;

displaying a first range of gray elements with a dithered approximately 50% gray background;

selecting the gray element in the first range that appears to most closely blend with the background; and

estimating the gamma of each of the display devices based on the gray level of the selected gray element.

19. The system of claim 18, wherein the color profiling process further includes:

displaying ranges of gray elements for the red, green, and blue color channels of the display device with dithered approximately 50% gray red, green and blue backgrounds;

selecting the red, green, and blue gray elements that appear to most closely blend with the respective backgrounds; and

estimating individual gammas for the red, green, and blue color channels based on the selected red, green, and blue gray elements.

20. The system of claim 12, wherein the web pages generated by the color profile server, when executed by one of the clients, generates a web cookie based on results of the color profiling process, each of the clients transmitting the web cookie to one of remote servers for correction of the color images.