Method and apparatus for capturing and transmitting screen images

• US 7,518,614 B2
• Filed: 08/23/2005
• Issued: 04/14/2009
• Est. Priority Date: 08/23/2004
• Status: Active Grant

• Current Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Emerson, Theodore F., Noonan, Robert L., Heinrich, David F., Dykes, Don
• Primary Examiner(s): Nguyen; Phu K
• Application Number:
  US11/210,082
• Publication Number:
  US 20060039468A1
• Time in Patent Office: 1,330 Days
• Field of Search: 345/502, 710/106, 710/302, 709/219, 709/222
• US Class Current: 345/502
• CPC Class Codes: G06F 11/2294 by remote test
• CPC Class Codes: G06F 3/1454 involving copying of the display data of a local workstation or window to a remote workstation or window so that an actual copy of the data is displayed simultaneously on two or more displays, e.g. teledisplay
• 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: G09G 2340/02 Handling of images in compressed format, e.g. JPEG, MPEG
• CPC Class Codes: H04L 1/0061 Error detection codes
• CPC Class Codes: H04L 1/0072 Error control for data other than payload data, e.g. control data
• CPC Class Codes: H04L 2001/0094 Bus
• CPC Class Codes: H04N 19/132 Sampling, masking or truncation of coding units, e.g. adaptive resampling, frame skipping, frame interpolation or high-frequency transform coefficient masking
• CPC Class Codes: H04N 19/137 Motion inside a coding unit, e.g. average field, frame or block difference
• CPC Class Codes: H04N 19/164 Feedback from the receiver or from the transmission channel
• CPC Class Codes: H04N 19/174 the region being a slice, e.g. a line of blocks or a group of blocks
• CPC Class Codes: H04N 19/176 the region being a block, e.g. a macroblock
• 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 19/436 using parallelised computational arrangements
• CPC Class Codes: H04N 19/507 using conditional replenishment
• CPC Class Codes: H04N 21/4334 Recording operations recording of a television signal H04N5/76; arrangements for recording or accumulating broadcast information or broadcast-related information H04H60/27
• CPC Class Codes: H04N 21/6332 directed to client

Abstract

A remote management controller may include a video redirection device and a processor. The video redirection device may be configured to: obtain multiple separate slices of video data output from a video graphics controller; calculate at least one value correlative to each of the multiple separate slices of video data; and if the calculated value for any portion of any of the multiple separate slices differs from a value for a previously obtained corresponding portion, update a table associated with an image related to a remote system with the calculated value, process the portion of the slice into a network packet, and move the network packet to one of multiple network buffers. The processor may be configured to: allocate the multiple network buffers; and facilitate transmission of the network packets loaded into the network buffers to the remote system.

Claims

1. A remote management controller comprising:

a video redirection device configured to;

obtain multiple separate slices of video data output from a video graphics controller,

calculate at least one value correlative to each of the multiple separate slices of video data,

if the calculated value for any portion of any of the multiple separate slices differs from a value for a previously obtained corresponding portion, update a table associated with an image related to a remote system with the calculated value, process the portion of the slice into a network packet, and move the network packet to one of multiple network buffers; and

a processor configured to;

allocate the multiple network buffers; and

facilitate transmission of the network packets loaded into the network buffers to the remote system.

2. The remote management controller, as set forth in claim 1, wherein the processor is configured to allocate one of the multiple network buffers while a first of the network buffers is being loaded by the video redirection device and while a second of the network buffers is being transmitted to the remote system.

3. The remote management controller, as set forth in claim 1, wherein the video redirection device comprises an encoder engine that moves the network packet to a second of the multiple network buffers while a first of the multiple network buffers is being transmitted to the remote system.

4. The remote management controller, as set forth in claim 3, wherein the encoder engine is configured to process the video data by compressing the video data.

5. The remote management controller, as set forth in claim 3, wherein the encoder engine is configured to process the video data by encoding the video data.

6. The remote management controller, as set forth in claim 3, wherein the encoder engine is configured to process the video data by encrypting the video data.

7. The remote management controller, as set forth in claim 1, wherein the at least one value comprises a cyclic redundancy check.

8. The remote management controller, as set forth in claim 1, wherein the video redirection device comprises a capture engine, the capture engine comprising multiple capture buffers, each capture buffer being configured to store one of the multiple separate slices of video data.

9. The remote management controller, as set forth in claim 1, wherein the video data is obtained from a direct video output of the video graphics controller.

10. The remote management controller, as set forth in claim 1, wherein the video redirection device comprises a throttle agent configured to control the capture and transmission of video data.

11. The remote management controller, as set forth in claim 10, wherein the remote management controller captures and transmits an entire screen image under control of the throttle agent.

12. A method of processing video data for transmission to a remote system, the method comprising:

obtaining multiple separate slices of video data output from a video graphics controller;

calculating at least one value correlative to each of the multiple separate slices of video data;

allocating multiple network buffers;

if the calculated value for any portion of any of the multiple separate slices differs from a value for a previously obtained corresponding portion, updating a table associated with an image related to a remote system with the calculated value, processing the portion of the slices into a network packet, and moving the network packet to one of the multiple network buffers; and

transmitting the network packet in the one of the multiple network buffers to the remote system.

13. The method, as set forth in claim 12, comprising storing each of the multiple slices of video data in a respective one of multiple capture buffers.

14. The method, as set forth in claim 12, comprising allocating one of the multiple network buffers while a first of the multiple network buffers is being loaded with the network packet and while a second of the multiple network buffers is being transmitted to the remote system.

15. The method, as set forth in claim 14, wherein calculating the at least one value comprises calculating a cyclic redundancy check.

16. The method, as set forth in claim 12, comprising throttling the obtaining and the transmission of video data.

17. The method, as set forth in claim 12, wherein obtaining the multiple slices of video data comprises obtaining the multiple slices of video data from a direct video output of the video graphics controller.

18. The method, as set forth in claim 12, wherein processing the block of video data into the network packet comprises compressing the video data.

19. The method, as set forth in claim 12, wherein processing the video data into the network packet comprises encoding the video data.

20. The method, as set forth in claim 12, wherein processing the video data into the network packet comprises encrypting the video data.

21. The method, as set forth in claim 12, comprising obtaining multiple slices of video data corresponding to an entire screen image and transmitting the entire screen image to the remote system under control of a throttling agent.

22. A computer comprising:

at least one central processing unit;

main memory accessible by the at least one central processing unit;

a video graphics controller configured to receive video data from the at least one central processing unit and to generate a video data output;

a remote management controller coupled to receive the video data output from the video graphics controller, the remote management controller comprising a video redirection device and a processor,

the video redirection device being configured to;

obtain multiple separate slices of video data output from a video graphics controller,

calculate at least one value correlative to each of the multiple separate slices of video data,

if the calculated value for any portion of any of the multiple separate slices differs from a value for a previously obtained corresponding portion, update a table associated with an image related to a remote system with the calculated value, process the portion of the slice into a network packet, and move the network packet to one of multiple network buffers; and

the processor being configured to;

allocate the multiple buffers;

facilitate transmission of the network packets loaded into the network buffers to the remote system.

23. The computer, as set forth in claim 22, wherein the processor is configured to allocate one of the multiple network buffers while a first of the network buffers is being loaded by the video redirection device and while a second of the network buffers is being transmitted to the remote system.

24. The computer, as set forth in claim 22, wherein the video redirection device comprises an encoder engine that moves the network packet to a second of the multiple network buffers while a first of the multiple network buffers is being transmitted to the remote system.

25. The computer, as set forth in claim 24, wherein the encoder engine is configured to process the video data by compressing the video data.

26. The computer, as set forth in claim 24, wherein the encoder engine is configured to process the video data by encoding the video data.

27. The computer, as set forth in claim 24, wherein the encoder engine is configured to process the video data by encrypting the video data.

28. The computer, as set forth in claim 22, wherein the at least one value comprises a cyclic redundancy check.

29. The computer, as set forth in claim 22, wherein the video redirection device comprises a capture engine, the capture engine comprising multiple capture buffers, each capture buffer being configured to store one of the multiple separate slices of video data.

30. The computer, as set forth in claim 22, wherein the slice of video data is obtained from a direct video output of the video graphics controller.

31. The computer, as set forth in claim 22, wherein the video redirection device comprises a throttle agent configured to control the capture and transmission of video data.

32. The computer, as set forth in claim 31, wherein the remote management controller captures and transmits an entire screen image under control of the throttle agent.