SCREEN TRANSFER APPARATUS AND METHOD THEREOF AND PROGRAM STORAGE MEDIUM

• US 20090324110A1
• Filed: 03/16/2009
• Published: 12/31/2009
• Est. Priority Date: 06/30/2008
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Murai, Shinya, Yamaguchi, Shogo, Yamaguchi, Kensaku, Fujinuki, Mitsue
• Granted Patent: US 8,576,237 B2
• Time in Patent Office: Days
• US Class Current: 382/232
• CPC Class Codes: H04N 19/30 using hierarchical techniques, e.g. scalability H04N19/63 takes precedence

Abstract

An apparatus that communicates with a screen display apparatus: a generation unit configured to generate image data to be displayed on a screen; an identification unit configured to identify an overlapping area that overlaps with the image data for each of a plurality of divided areas into which the screen is divided, respectively; a division unit configured to divide respective partial image data belonging to the respective overlapping areas in a vertical direction or a horizontal direction of the screen; a data compression processor configured to compress respective divided image data belonging to the respective divided areas by using dictionary data obtained based on a predetermined amount of divided image data compressed in the past belonging to the respective divided areas; and a data transmission unit configured to transmit respective compressed image data belonging to the respective divided areas in an order defined according to a rule given in advance.

Claims

1. A screen transfer apparatus that communicates with a screen display apparatus that displays image data on a screen, comprising:

an image data generation unit configured to generate image data to be displayed on the screen;

an area identification unit configured to identify an overlapping area that overlaps with the image data for each of a plurality of divided areas into which the screen is divided, respectively;

a division unit configured to divide respective partial image data belonging to respective overlapping areas in a vertical direction or a horizontal direction of the screen to generate divided image data for the respective divided areas, respectively;

a data compression processor configured to compress respective divided image data belonging to the respective divided areas by using dictionary data obtained based on a predetermined amount of divided image data compressed in the past belonging to the respective divided areas so that compressed image data are generated for the respective divided areas; and

a data transmission unit configured to transmit respective compressed image data belonging to the respective divided areas in an order defined according to a rule given in advance.

2. The apparatus according to claim 1, wherein the division unit performs division in a vertical direction, and

the data transmission unit transmits the respective compressed image data so that the compressed image data at higher positions in the vertical direction of the screen is earlier transmitted.

3. The apparatus according to claim 2, wherein the data transmission unit performs transmission, when plural compressed image data are located at the same height, so that the compressed image data closer to a left side in the horizontal direction of the screen is earlier transmitted.

4. The apparatus according to claim 2, wherein the division unit performs division so that a vertical width of the divided image data becomes equal to or less than a vertical width of a character font size displayed on the screen display apparatus.

5. The apparatus according to claim 1, wherein the division unit performs division in the horizontal direction of the screen, and

the data transmission unit transmits the respective compressed image data so that the compressed image data closer to the right side in the horizontal direction of the screen is earlier transmitted.

6. The apparatus according to claim 5, wherein the data transmission unit performs transmission, when plural compressed image data are located at the same position in the horizontal direction, so that the compressed image data at higher positions in the vertical direction of the screen is earlier transmitted.

7. The apparatus according to claim 5, wherein the division unit performs division so that a horizontal width of the divided image data becomes equal to or less than a horizontal width of a character font display size displayed on the screen display apparatus.

8. The apparatus according to claim 1, further comprising a plurality of dictionary memories configured to store a predetermined amount of divided image data compressed in the past belonging to the respective divided areas.

9. The apparatus according to claim 8, wherein the data compression processor comprises a plurality of data compression units configured to compress divided image data belonging to the respective divided areas by using dictionary memories belonging to the respective divided areas.

10. The apparatus according to claim 8, wherein the data compression processor performs compression, when data having a same pattern as data in the dictionary memory are included in the divided image data, by replacing the data included in the divided image data with both a length of the pattern and a distance from tail end of data stored in the dictionary memory to the data having the pattern stored in the dictionary memory, and

the division unit performs division so that data size of the divided image data becomes equal to or greater than an upper limit value of replaceable pattern length given in advance and equal to or less than a capacity of the dictionary memory.

11. The apparatus according to claim 1, wherein a plurality of dictionary memories are provided for a first divided area in correspondence with a plurality of mutually overlapping windows in the first divided area, and

the data compression processor compresses the divided image data belonging to the first divided area by using a dictionary memory corresponding to an uppermost window of the plurality of windows.

12. The apparatus according to claim 1, wherein first and second dictionary memories are provided for a second divided area in correspondence with first and second windows displayed in the second divided area,

the data compression processor compresses, when divided image data belonging to the second divided area is included in an actually displayed first area of the first window and not included in an actually displayed second area of the second window, the divided image data belonging to the second divided area by using the first dictionary memory,

compresses, when the divided image data belonging to the second divided area is not included in the first area but included in the second area, the divided image data belonging to the second divided area by using the second dictionary memory, and

compresses, when the divided image data belonging to the second divided area extends over both the first and second areas or is included in none of the first and second areas, the divided image data belonging to the second divided area by using one of the first and second dictionary memories.

13. The apparatus according to claim 1, wherein first and second dictionary memories are provided for a third divided area in correspondence with first and second windows displayed in a third divided area,

the data compression processor compresses, when divided image data belonging to the third divided area is included in an actually displayed first area of the first window and not included in an actually displayed second area of the second window, the divided image data belonging to the third divided area by using the first dictionary memory,

compresses, when divided image data belonging to the third divided area is not included in the first area but included in the second area, the divided image data belonging to the third divided area by using the second dictionary memory,

generates, when the divided image data belonging to the third divided area extends over both the first and second areas, separated image data by separating the divided image data between the first and second areas, compresses the separated image data belonging to the first area by using the first dictionary memory, compresses the separated image data belonging to the second area by using the second dictionary memory, and

compresses, when the divided image data belonging to the third divided area is included in none of the first and second areas, the divided image data belonging to the third divided area by using one of the first and second dictionary memories.

14. The apparatus according to claim 1, wherein the data compression processor uses a predetermined amount of divided image data compressed immediately before compressing the divided image data belonging to the divided area as dictionary data for the divided area.

15. The apparatus according to claim 1, wherein one side of the divided area in a vertical or horizontal direction in which the screen is predicted to be scrolled at a high frequency is made longer than the other side in the other direction.

16. A screen transfer apparatus that communicates with a screen display apparatus that displays image data on a screen, comprising:

an image data generation unit configured to generate image data corresponding to a window displayed on the screen of the screen display apparatus;

a division unit configured to divide image data corresponding to the window in a vertical direction or horizontal direction of the screen to generate divided image data;

a data compression processor configured to compress the divided image data corresponding to the window by using dictionary data obtained based on a predetermined amount of divided image data compressed in the past corresponding to the window so that compressed image data are generated correspondingly to the divided image date; and

a data transmission unit configured to transmit the compressed image data corresponding to the window in an order defined according to a rule given in advance.

17. A screen transfer method that communicates with a screen display apparatus that displays image data on a screen, comprising:

generating image data to be displayed on the screen;

identifying an overlapping area that overlaps with the image data for each of a plurality of divided areas into which the screen is divided, respectively;

dividing respective partial image data belonging to respective overlapping areas in a vertical direction or a horizontal direction of the screen to generate divided image data for the respective divided areas, respectively;

compressing respective divided image data belonging to the respective divided areas by using dictionary data obtained based on a predetermined amount of divided image data compressed in the past belonging to the respective divided areas so that compressed image data are generated for the respective divided areas, respectively; and

transmitting respective compressed image data belonging to the respective divided areas in an order defined according to a rule given in advance.

18. A program storage medium storing a computer program for causing a computer that communicates with a screen display apparatus that displays image data on a screen, to execute instructions to perform the steps of:

generating image data to be displayed on the screen;

identifying an overlapping area that overlaps with the image data for each of a plurality of divided areas into which the screen is divided, respectively;

dividing respective partial image data belonging to respective overlapping areas in a vertical direction or a horizontal direction of the screen to generate divided image data for the respective divided areas, respectively;

compressing respective divided image data belonging to the respective divided areas by using dictionary data obtained based on a predetermined amount of divided image data compressed in the past belonging to the respective divided areas so that compressed image data are generated for the respective divided areas, respectively; and

transmitting respective compressed image data belonging to the respective divided areas in an order defined according to a rule given in advance.