Method and system for transmitting data for a shared application

• US 20060168356A1
• Filed: 06/03/2004
• Published: 07/27/2006
• Est. Priority Date: 07/05/1995
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: MacFarquhar, Roderick F., Pollitt, Alex J., Batty, John P., Downes, Anthony M., Hughes, Kenneth P., Mairs, Christopher J., Berry, Mark E.
• Granted Patent: US 7,404,014 B2
• Time in Patent Office: Days
• US Class Current: 710/1
• CPC Class Codes: G06F 3/1462 with means for detecting differences between the image stored in the host and the images displayed on the remote displays
• CPC Class Codes: G06T 9/005 Statistical coding, e.g. Huffman, run length coding

Abstract

A method and system for compressing bitmap data in a system for sharing an application running on a host computer with a remote computer, wherein the shared application'"'"'s screen output is simultaneously displayed on both computers. Simultaneous display of screen output is achieved by efficiently transmitting display data between the host computer and the remote computer. When a font used by the host computer for displaying text is not available on the remote computer, the host computer sends a bitmap representation of the text for display, rather than the text itself. Bitmap representations are cached by the remote computer, so that the same bitmap representation need not be repeatedly transmitted from the host computer to the remote computer. Bitmap representations are compressed by the host computer prior to transmission, transmitted, then decompressed by the computer.

Claims

1-12. -12. (canceled)

13. A method for transmitting display orders from a host computer system, each display order when performed having an effect on a display, the method comprising:

receiving a plurality of display orders;

for each of the plurality of received display orders,

determining whether the effect of the display order on the display is relied upon by another display order; and

when the effect of the display order on the display is relied on by another display order, transmitting the display order even though the display order would have no visible effect after performing all of the plurality of display orders.

14. The method of claim 13 wherein the determining includes determining whether the other display order is to copy at least a portion of the effect of the display order.

15. The method of claim 13 wherein each display order that is received before the other display order that relies upon the effect of the display order is transmitted.

16. The method of claim 13 wherein the transmitted display orders are capable of being performed on a remote computer:

under control of the remote computer system,

receiving the transmitted display orders; and

performing each of the received display order to effect the display of the remote computer system.

17. A system for transmitting display orders representing operations to be performed on a display, the method comprising:

a first component that receives a display order, stores the received display order in a queue, and compares the received display orders with display orders already stored in the queue and removes from the queue display orders that represent operations that would be obscured by the operation of the received display order except for display orders already in the queue that are relied upon by subsequently received display orders; and

a second component that periodically retrieves the display order from the queue, and sends the retrieved display order to perform the operation represented by the retrieved display order on a display.

18. The system of claim 17 wherein the determining includes determining whether the other display order is to copy at least a portion of the effect of the display order.

19. The system of claim 17 wherein each display order that is received before the other display order that relies upon the effect of the display order is transmitted.

20. The system of claim 17 wherein the sent retrieved display order is capable of being executed on a display of a remote computer system.

21. A computer-readable storage device containing instructions for controlling a computer system to transmit display orders from a host computer system to a shadow computer, each display order when performed having an effect on a display, by:

receiving a plurality of display orders;

for each of the plurality of received display orders, determining whether the effect of the display order on the display would be visible after performing the plurality of display orders; and

when the effect of the display order on the display would be visible or when the effect on the display order in the display would not be visible but a subsequently received display order relies upon the effect of the display order, transmitting the display order to the shadow computer system.

22. The computer-readable storage device of claim 21 wherein determination of whether the effect of the display order on the display would be visible after performing the plurality of display orders further includes determining whether the effect of the display order is obscured by the effect of another display order.

23. The computer-readable storage device of claim 22 wherein each display order has a bounding area that indicates an area of the display in which the display order has an effect and wherein the determining of whether any visible effect of the display order is obscured further includes determining whether the bounding area of second display order encompasses the bounding area of the display order and the second display order is to be performed after the display order.

24. The computer-readable storage device of claim 21 including determining whether the visible effect of the display order is obscured by the combined effect of multiple display orders.

25. The computer-readable storage device of claim 21 wherein the receiving of a plurality of display orders further includes storing each of the plurality of display orders in a queue, and the determination of whether the effect of the display order on the display would be visible after performing the plurality of display orders further includes retrieving a display order from the queue and determining whether the effect of the retrieved display order on the display would be visible after performing all of the display orders that are currently in the queue.

26. The computer-readable storage device of claim 21 wherein the transmitted display orders are capable of being performed on the shadow computer system.

27. A computer-readable storage device containing instructions for controlling a computer system to transmit display orders representing operations to be performed on a display by:

for each of a plurality of display orders, receiving the display order;

storing the received display order; and

comparing the received display order with display orders already stored and removing display orders that represent operations that would be obscured by the operation of the received display order unless a subsequent display order relies upon the operations that would be obscured;

retrieving a display order; and

sending the retrieved display order to perform the operation represented by the retrieved display order on a display.