Method for transmitting text data for shared application between first and second computer asynchronously upon initiation of a session without solicitation from first computer

• US 6,216,177 B1
• Filed: 07/01/1998
• Issued: 04/10/2001
• Est. Priority Date: 07/05/1995
• Status: Expired due to Term

• 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.
• Primary Examiner(s): Lee, Thomas C.
• Assistant Examiner(s): PEYTON, TAMMARA R
• Application Number:
  US09/108,882
• Time in Patent Office: 1,014 Days
• Field of Search: 710/6, 345/522, 395/200.34, 709/204
• US Class Current: 710/6
• 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 remote computer.

Claims

1. A method in a first computer for transmitting text data from a first computer to a second computer, the method comprising:

the first computer receiving identifications of fonts supported by the second computer asynchronously, upon initiation of a session for transmitting data, and without solicitation form the first computer;

the first computer receiving a request to output text data in a specified font on the second computer;

the first computer determining from the received identifications whether the second computer supports the specified font;

when it is determined, by the first computer, that the second computer supports the specified font, sending the text data along with an identification of the specified font to the second computer; and

when it is determined, by the first computer, that the second computer does not support the specified font,

the first computer generating a bitmap representation of the data in the specified font; and

the first computer sending the generated bitmap representation of the text data of the second computer for display of the bitmap representation on a display device of the second computer.

2. A computer-readable medium containing instructions for causing a first computer to transmit text data to a second computer, by:

the first computer determining from identifications of fonts supported by the second computer whether the second computer supports a specified font, the first computer receiving the identifications from the second computer asynchronously upon initiation of a session to transmit text data and without solicitation by the first computer;

when it is determined, by the first computer, that the second computer supports the specified font, the first computer sending text data along with an identification of the specified font to the second computer; and

when it is determined, by the first computer, that the second computer does not support the specified font, the first computer sending a bitmap representation of the text data in the specified font to the second computer for display of the bitmap representation on a display device of the second computer.

3. A method in a first computer for transmitting text data to a second computer, the method comprising:

the first computer receiving a request to transmit text data from the first computer to the second computer;

the first computer determining from identifications of fonts supported by the second computer whether the second computer supports a specified font, the identifications being received from the second computer asynchronously upon initiation of a session for transmitting text data and without solicitation by the first computer;

when it is determined by the first computer that the second computer does support the specified font, the first computer sending text data along with an identification of the specified font to the second computer; and

when it is determined, by the first computer, that the second computer does not support the specified font, the first computer sending a bitmap representation of the text data in the specified font to the second computer for display of the bitmap representation on a display device of the second computer.