Image display device, image display method, and image display program

• US 20030179219A1
• Filed: 03/06/2003
• Published: 09/25/2003
• Est. Priority Date: 03/08/2002
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Wada, Takahide, Mori, Hidetoshi, Nakano, Masayoshi, Graham, Jon Earl
• Granted Patent: US 6,972,771 B2
• Time in Patent Office: Days
• US Class Current: 345/660
• CPC Class Codes: G06F 2203/04805 Virtual magnifying lens, i.e. window or frame movable on top of displayed information to enlarge it for better reading or selection
• CPC Class Codes: G06F 3/0481 based on specific properties of the displayed interaction object or a metaphor-based environment, e.g. interaction with desktop elements like windows or icons, or assisted by a cursor's changing behaviour or appearance
• CPC Class Codes: G09G 2320/0626 for control of overall brightness
• CPC Class Codes: G09G 2320/066 for control of contrast
• CPC Class Codes: G09G 2320/0666 for control of colour parameters, e.g. colour temperature
• CPC Class Codes: G09G 2320/0686 with two or more screen areas displaying information with different brightness or colours
• CPC Class Codes: G09G 2340/045 Zooming at least part of an image, i.e. enlarging it or shrinking it
• CPC Class Codes: G09G 5/00 Control arrangements or circuits for visual indicators common to cathode-ray tube indicators and other visual indicators image data processing or generation, in general G06T

Abstract

A technique is provided for improving visual recognition of letters, graphics, etc., in a portion of a displayed image that has been enlarged. An image display system includes an image display component for displaying on a screen an image based on image data, a region indicator component for permitting a region to be enlarged from the image to be selected and identified, a data modification component for modifying the portion of the image data corresponding to an enlarged display region so that the selected image is enlarged and displayed within the enlarged display region on the screen, and a brightness adjusting component for adjusting values instructing brightness of the corresponding image data part such that a contrast of the image within the enlarged display is higher than a contrast of the original image within the enlarged display region.

Claims

1. In a computing environment, an image display system for permitting a portion of an image to be enlarged, said system comprising:

image display means for displaying on a screen an image based on image data;

region indicator means for identifying a region of the image to be enlarged;

brightness adjusting means for adjusting brightness values of a portion of the image which corresponds to the region to be enlarged such that a contrast of the identified region when displayed within an enlarged display area on the screen is higher than a contrast of an original image within the enlarged display region; and

data modification means for modifying a portion of the image data which corresponds to the enlarged display area within the image data so that the identified region of the image, after enlargement within the enlarged display region is enlarged and displayed in the enlarged display region on the screen.

2. The image display system according to claim 1, wherein said brightness adjusting means adjusts the values of brightness by changing each value of brightness using a function represented by a predetermined line on a graph where horizontal axis indicates values of brightness before change and a vertical axis indicates values of brightness after change, or by changing each value of brightness in an equivalent manner.

3. The image display system according to claim 2, wherein the image data is in RGB format, and said brightness adjusting means adjusts the values of brightness by changing RGB values for each item in the identified region.

4. The image display device according to claim 1, wherein said brightness adjusting means adjusts the values of brightness in consideration of the brightness of the original image in said enlarged region.

5. The image display system according to claim 1, said brightness adjusting means uses a function obtained by shifting said function parallel in the direction of said horizontal axis based on an average value of brightness of the image data for the original image in said enlarged region.

6. The image display system according to claim 2, wherein said predetermined line has a straight segment having a gradient equal to or greater than 1, said straight segment being obtained in such a manner that a function line having a gradient of 1 and causing no change in said values of brightness is rotated about a point on the function line corresponding to the midpoint of said values of brightness.

7. The image display system according to claim 2, wherein said predetermined line has segments corresponding to both ends of the range of the values of brightness where the gradient is above 0 and below 1, and a segment in between said segments where the gradient is equal to or above 1.

8. A method for enlarging a selected region of an image displayed on a screen, display method comprising the steps of:

displaying on a screen an image based on image data;

identifying a region to be enlarged from within the displayed image and identifying a first portion of the image data which corresponds to the region to be enlarged and a second portion of the image data which corresponds to a enlarged display region for the region to be enlarged;

modifying the first image data portion and the second image data portion corresponding to the enlarged display region within said image data so that the first image data portion is enlarged for display in the enlarged display region on the screen;

adjusting values instructing brightness of the first image data portion such that a contrast of a resulting image within the enlarged display region is higher than a contrast of an original image within the enlarged region; and

displaying the enlarged and brightness adjusted image corresponding to the second data image portion in the enlarged display region.

9. The method according to claim 8, wherein said adjusting step comprises adjusting the values of brightness by changing each value of brightness using a function represented by a predetermined line on a graph where a horizontal axis indicates values of brightness before change and a vertical axis indicates values of brightness after change, or by changing each value of brightness in an equivalent manner.

10. The method according to claim 9, wherein said image data is in RGB format, and said adjusting step comprises adjusting the values of brightness by changing RGB values of each image data item concerned.

11. The method according to claim 8, wherein said adjusting step further comprises adjusting the values of brightness in consideration of the brightness of the original image in the enlarged display region.

12. The method according to claim 8, wherein said said adjusting step comprises adjusting the values of brightness by changing each brightness value, using a function obtained by shifting the function parallel in the direction of said horizontal axis based on an average value of brightness of the image data for the original image in the enlarged region.

13. The image display method according to claim 9, wherein the predetermined line has a straight segment having a gradient equal to or above 1, the straight segment being obtained in such a manner that a function line having a gradient of 1 and causing no change in the values of brightness is rotated about a point on the function line corresponding to the midpoint of the values of brightness.

14. The image display method according to claim 9, wherein the predetermined line has segments corresponding to both ends of the range of the values of brightness where the gradient is above 0 and below 1, and a segment in between the segments where the gradient is equal to or above 1.

15. Computer readable code that causes a computer to enlarge and enhance a portion of an image displayed on a screen, said computer readable code comprising:

first code means for displaying on a screen an image based on image data;

second code means for identifying a region to be enlarged in said displayed image and displayed in an enlarged display region, the identified region being within the enlarged display region;

third code means for modifying first image data parts corresponding to the enlarged display region within said image data so that the identified region is enlarged for display in the enlarged display region on said screen;

fourth code means for adjusting values instructing brightness of a portion of the first image data parts corresponding to the identified region such that a contrast of the adjusted portion of the first image data parts becomes higher than a contrast of an original image within said enlarged display region; and

fifth code means for displaying the enlarged and brightness adjusted identified image in the enlarged display region.

16. The computer readable code according to claim 15, wherein said fourth code means adjusts the values of brightness by changing each value of brightness using a function represented by a predetermined line on a graph where a horizontal axis indicates values of brightness before change and a vertical axis indicates values of brightness after change, or by changing each value of brightness in an equivalent manner.

17. The computer readable code program according to claim 16, wherein said image data is in RGB format, and said fourth code means adjusts the values of brightness by changing RGB values of each image data item concerned.

18. The computer code according to claim 15, wherein said fourth code means adjusts the values of brightness in consideration of the brightness of the original image in the enlarged region.

19. The computer readable code according to claim 16, wherein instead of using said function, said fourth code means uses a function obtained by shifting said function parallel in the direction of the horizontal axis based on the average value of brightness of the image data for the original image in the enlarged region.

20. The computer readable code according to claim 16, wherein the predetermined line has a straight segment having a gradient equal to or above 1, the straight segment being obtained in such a manner that a function line having a gradient of 1 and causing no change in the values of brightness is rotated about a point on the function line corresponding to the midpoint of the values of brightness.

21. The computer readable code according to claim 16, wherein the predetermined line has segments corresponding to both ends of the range of said values of brightness where the gradient is above 0 and below 1, and a segment in between said segments where the gradient is equal to or above 1.

22. The computer readable code according the claim 15, further comprising:

sixth code means for storing an original portion of the image data corresponding to the enlarged display region;

wherein said third code means and said fourth code means utilizes the stored original portion of the image data to change the displayed image if the identified region to be enlarged changes.

23. Computer readable code according to claim 15, wherein said second coded means re-identifies the region to be enlarged at predetermined time intervals, and, if the identified region of the image to be enlarged has changed, applying said third and fourth code means for the changed region of the image to be enlarged.