Updating image in buffer via difference data

• US 8,601,184 B2
• Filed: 12/26/2012
• Issued: 12/03/2013
• Est. Priority Date: 09/28/2010
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Fleegal, Eric, Whitman, Chris, Tian, Xianfeng, Vattakandy, Amar S., Belesiu, Jim, Young, Robert D.
• Primary Examiner(s): Lee, Chun-Kuan
• Assistant Examiner(s): Franklin, Richard B
• Application Number:
  US13/726,851
• Publication Number:
  US 20130106884A1
• Time in Patent Office: 342 Days
• Field of Search: None
• US Class Current: 710/52
• CPC Class Codes: G06F 3/1415 with means for detecting differences between the image stored in the host and the images displayed on the displays
• CPC Class Codes: G06T 9/00 Image coding bandwidth or redundancy reduction for static pictures H04N1/41; coding or decoding of static colour picture signals H04N1/64; methods or arrangements for coding, decoding, compressing or decompressing digital video signals H04N19/00
• CPC Class Codes: G09G 5/39 Control of the bit-mapped memory
• CPC Class Codes: G09G 5/399 using two or more bit-mapped memories, the operations of which are switched in time, e.g. ping-pong buffers
• CPC Class Codes: H04N 19/42 characterised by implementation details or hardware specially adapted for video compression or decompression, e.g. dedicated software implementation H04N19/635 takes precedence
• CPC Class Codes: H04N 19/507 using conditional replenishment
• CPC Class Codes: H04N 19/58 Motion compensation with long-term prediction, i.e. the reference frame for a current frame not being the temporally closest one H04N19/23 takes precedence
• CPC Class Codes: H04N 21/4122 additional display device, e.g. video projector digital output for controlling a plurality of local displays G06F3/1423
• CPC Class Codes: H04N 21/44004 involving video buffer management, e.g. video decoder buffer or video display buffer
• CPC Class Codes: H04N 21/4402 involving reformatting operations of video signals for household redistribution, storage or real-time display details of conversion of video standards at pixel level H04N7/01; video transcoding H04N19/40; adapting incoming signals to the display format of the display terminal G09G5/005; media handling at the source in data packet switching networks H04L65/764

Abstract

Various embodiments related to a host computing device for rendering and sending image data to a peripheral device for display at the peripheral device. For example, one embodiment comprises a host computing device, the host computing device comprising a data storage subsystem and a logic subsystem. The host computing device further comprises instructions stored in the data storage subsystem and executable by the logic subsystem to output to the peripheral device a frame of image data representing a difference between a currently rendered image and an (N−1)-th previously rendered image, N being an integer and having a value of 3 or more.

Claims

1. A peripheral device, comprising:

a display;

a logic subsystem; and

a data storage subsystem storing instructions executable by the logic subsystem to display images sent from a host computing device to the peripheral device by;

receiving difference image data comprising a difference between a current frame of image data and an (N−

1)-th previously received frame of image data, N being an integer and having a value of 3 or more;

forming a display image by updating a stored image held in a peripheral device image buffer chain with the difference image data, the peripheral device image buffer chain comprising N image buffers; and

displaying the display image via the display.

2. The peripheral device of claim 1, wherein the difference image data comprises all differences between the current frame of image data and the (N−

1)-th previously received frame of image data.

3. The peripheral device of claim 1, wherein the difference image data comprises changed regions for at least N previously received frames of image data.

4. The peripheral device of claim 3, wherein each changed region comprises a rectangular shape.

5. The peripheral device of claim 1, wherein the instructions are executable to store the stored image in a back buffer of the peripheral device image buffer chain.

6. The peripheral device of claim 5, wherein the instructions are further executable to advance a front buffer pointer and a back buffer pointer of the peripheral device buffer chain after forming the display image.

7. The peripheral device of claim 1, wherein the instructions are executable to form the display image by updating the stored image without forward copying of a frame of image data.

8. On a peripheral device, a method of displaying images sent from a host computing device to the peripheral device for display on a display of the peripheral device, the peripheral device including a peripheral device image buffer chain comprising N image buffers, the method comprising:

receiving first difference image data comprising a difference between a first current frame of image data and an (N−

1)-th previously received frame of image data, N being an integer and having a value of 3 or more;

forming a first display image by updating a stored image held in a back buffer of the peripheral device image buffer chain with the first difference image data, the peripheral device image buffer chain comprising N image buffers including the back buffer and a front buffer;

advancing a front buffer pointer and a back buffer pointer such that a buffer location that was previously the back buffer becomes the front buffer;

displaying the first display image;

after receiving the first difference image data, receiving second difference image data comprising a difference between a second current frame of image data and an (N−

1)-th previously received frame of image data;

forming a second display image by updating a stored image held in the back buffer of the peripheral device image buffer chain with the second difference image data;

advancing the front buffer pointer and the back buffer pointer; and

displaying the second display image.

9. The method of claim 8, wherein the first difference image data comprises all differences between the first current frame of image data and the (N−

1)-th previously received frame of image data.

10. The method of claim 8, wherein the first difference image data comprises changed regions for at least N previously received frames of image data.

11. The method of claim 10, wherein each changed region comprises a rectangular shape.

12. The method of claim 8, further comprising forming the display image by updating the stored image without forward copying of a frame of image data.

13. A host computing device for rendering and sending image data to a peripheral device for display, the host computing device comprising:

a data storage subsystem;

a logic subsystem; and

instructions stored in the data storage subsystem and executable by the logic subsystem to;

determine a difference between a currently rendered image and an (N−

1)-th previously rendered image, N being an integer and having a value of 3 or more, and

output the difference as a frame of image data to the peripheral device.

14. The host computing device of claim 13, wherein the frame of image data comprises all differences between the currently rendered image and the (N−

1)-th previously rendered image.

15. The host computing device of claim 13, further comprising instructions to:

generate a host buffer chain comprising N buffers;

store the currently rendered image in a host back buffer of the host buffer chain; and

advance the host buffer chain after outputting the frame of image data to the peripheral device.

16. The host computing device of claim 15, wherein the host buffer chain is configured to simulate a peripheral buffer chain of the peripheral device.

17. The host computing device of claim 13, further comprising instructions executable to:

generate a region list chain, wherein the region list chain comprises N region lists;

accumulate changed regions in the region list chain, wherein each changed region comprises a difference between successive image frames;

include the changed regions for a previous N frames in the frame of image data output to the peripheral device; and

advance the region list chain.

18. The host computing device of claim 17, further comprising instructions to remove a hidden region from a number of the region lists.

19. The host computing device of claim 13, further comprising instructions to:

generate a tile list chain, wherein the tile list chain comprises N tile lists;

accumulate changed tiles in the tile list chain, wherein each changed tile comprises a difference between successive image frames;

include the changed tiles for a previous N frames in the frame of image data output to the peripheral device; and

advancing the tile list chain.

20. The host computing device of claim 19, wherein the instructions to accumulate changed tiles in the tile list chain further comprises instructions to generate a composite comprising the changed tiles from the previous N frames.