APPARATUS AND METHOD FOR HANDLING SPECIAL WINDOWS IN A DISPLAY

• US 20090037819A1
• Filed: 08/12/2008
• Published: 02/05/2009
• Est. Priority Date: 09/24/1998
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: CAPPELS, Richard D. SR., Krah, Christoph H., Andrews, Johanna M.
• Granted Patent: US 7,844,902 B2
• Time in Patent Office: Days
• US Class Current: 715/719
• CPC Class Codes: G09G 1/16 the pattern of rectangular co-ordinates extending over the whole area of the screen, i.e. television type raster
• CPC Class Codes: G09G 1/167 Details of the interface to the display terminal specific for a CRT details suitable for both CRT and flat panel G09G5/006, specific for a flat panel G09G3/2096
• CPC Class Codes: G09G 2320/02 Improving the quality of display appearance
• CPC Class Codes: G09G 2320/0686 with two or more screen areas displaying information with different brightness or colours
• CPC Class Codes: G09G 2370/04 Exchange of auxiliary data, i.e. other than image data, between monitor and graphics controller
• CPC Class Codes: G09G 5/10 Intensity circuits
• CPC Class Codes: G09G 5/14 Display of multiple viewports

Abstract

An apparatus and method for handling special windows in a display comprises a window manager in an operating system that is called by application programs to create special windows. The window manager embeds static key signals including encoded special window information, such as the coordinates of a window area to be specially processed, into a video RAM. An existing video interface scans the video RAM and transmits display information, including the key signals, to the display. The present invention further comprises a window decoder in the display, that detects the key signals, extracts the encoded special window information, and controls display circuitry performing the desired special processing. The key signal encoding scheme does not create visually discernible display aberrations that could distract the user or interfere with normal window management.

Claims

1. An apparatus for handling special windows in a display, comprising:

a window manager to embed special window information in a video signal; and

a window decoder to extract said special window information from said video signal and responsively generate a display control signal.

4. The apparatus of claim 1, further comprising:

a target area in said special windows to be specially processed in response to said display control signal;

and a video interface to transmit data including said special window information to said display.

5. The apparatus of claim 4, further comprising:

pixels contained in said display;

a first color signal serving as a video clock signal for said special window information;

a second color signal including said special window information; and

a third color signal.

6. The apparatus of claim 5, further comprising:

key signals including a pattern of bits of said special window information to encode a target area position, and corresponding to a pattern of said pixels depicted in said display.

13. The apparatus of claim 6, wherein scroll bars in said special windows function as controls for special processing.

14. The apparatus of claim 6, wherein said key signals include hidden watermarks.

15. The apparatus of claim 6, wherein said key signals include visibly apparent symbols.

16. The apparatus of claim 6, further comprising:

key signal verification circuits identifying said special windows and responsively enabling an attribute;

a vertical counter monitoring a number of vertically scanned lines of said pixels occurring after a vertical synchronization signal;

a horizontal counter monitoring a number of horizontally scanned pixels after a horizontal synchronization signal;

registers storing said target area position in terms of said vertically scanned lines and said horizontally scanned pixels when said attribute is enabled;

a comparator monitoring a position of said pixels in terms of said vertically scanned lines and said horizontally scanned pixels, comparing said position of said pixels to said target area position, and responsively generating said display control signal to enable special processing.

17. The apparatus of claim 16, further comprising:

an internal logic clock signal denoting an intended duration for said special processing of said pixels in said target area; and

a frequency control unit synchronizing said internal logic clock signal to said video clock signal to regulate a horizontal width of said pixels in said target area with a duration of said display control signal, thereby calibrating said special processing with a scan of said display.

18. The apparatus of claim 17, wherein said key signal verification circuits enable said attribute when a duration of said key signals in terms of internal logic clock signal periods is consistent with a key signal format.

19. The apparatus of claim 16, wherein said attribute is disabled by an absence of said key signals.

20. The apparatus of claim 16, wherein said key signal verification circuits enable said attribute when said key signals exist during one scan of said display and persist for a number of scans of said display.

2-3. -3. (canceled)

7-12. -12. (canceled)

21. A method for handling special windows in a display, comprising the steps of:

embedding special window information in a video signal;

extracting said special window information from said video signal using a window decoder; and

generating a display control signal in response to said window information to enable different processing of said special windows in said display.

24. The method of claim 21, further comprising the steps of:

specially processing a target area in said special windows in response to said display control signal; and

transmitting data including said special window information to said display using a video interface.

25. The method of claim 24, further comprising the steps of:

depicting pixels in said display;

transmitting a first color signal serving as a video clock signal for said special window information;

transmitting a second color signal including said special window information; and

transmitting a third color signal.

26. The method of claim 25, further comprising the step of:

transmitting key signals including a pattern of bits of said special window information to encode a target area position, and corresponding to a pattern of said pixels depicted in said display.

33. The method of claim 26, wherein scroll bars in said special windows function as controls for special processing.

34. The method of claim 26, wherein said key signals include hidden watermarks.

35. The method of claim 26, wherein said key signals include visibly apparent symbols.

36. The method of claim 26, further comprising the steps of:

identifying said special windows and responsively enabling an attribute using key signal verification circuits;

monitoring a number of vertically scanned lines of said pixels occurring after a vertical synchronization signal using a vertical counter;

monitoring a number of horizontally scanned pixels after a horizontal synchronization signal using a horizontal counter;

using registers to store said target area position in terms of said vertically scanned lines and said horizontally scanned pixels when said attribute is enabled;

using a comparator to monitor a position of said pixels in terms of said vertically scanned lines and said horizontally scanned pixels, to compare said position of said pixels to said target area position, and to responsively generate said display control signal to enable special processing.

37. The method of claim 26, further comprising the steps of:

denoting an intended duration for said special processing of said pixels in said target area using an internal logic clock signal; and

using a frequency control unit to synchronize said internal logic clock signal to said video clock signal and regulate a horizontal width of said pixels in said target area with a duration of said display control signal, thereby calibrating said special processing with a scan of said display.

38. The method of claim 36, wherein said key signal verification circuits enable said attribute when a duration of said key signals in terms of internal logic clock signal periods is consistent with a key signal format.

39. The method of claim 36, wherein said attribute is disabled by an absence of said key signals.

40. The method of claim 36, wherein said key signal verification circuits enable said attribute when said key signals exist during one scan of said display and persist for a number of scans of said display.

22-23. -23. (canceled)

27-32. -32. (canceled)

41-43. -43. (canceled)