Method and apparatus for managing remote display updates

• US 7,844,848 B1
• Filed: 09/25/2008
• Issued: 11/30/2010
• Est. Priority Date: 03/30/2005
• Status: Active Grant

• Current Assignee: Teradici Corporation (HP Inc.)
• Original Assignee: Teradici Corporation (HP Inc.)
• Inventors: Hobbs, David V.
• Primary Examiner(s): BUTLER, DENNIS
• Application Number:
  US12/284,831
• Time in Patent Office: 796 Days
• Field of Search: None
• US Class Current: 713/400
• CPC Class Codes: H04L 67/131 Protocols for games, networked simulations or virtual reality
• CPC Class Codes: H04L 69/28 Timers or timing mechanisms used in protocols

Abstract

A method of transmitting encoded computer display images between computers over a nondeterministic network is disclosed. During a display session in which images are transmitted from a host to a client, the client requests sections of encoded image updates at a predetermined time in advance of when the requested at least one section is to be transmitted by the display controller. When the requested section is received, a time value is compared to a display controller timing value and, if the difference between the compared times is outside of an acceptable range, the client adjusts a predetermined time at which time the client requests image sections from the host.

Claims

1. A method of managing remote display updates received by a remote computer, the remote computer in communication with a host computer over a network, the method comprising:

a) receiving a display update section from the host computer at a received time, the received time in relationship to a sequencing of a display controller at the remote computer;

b) displaying the display update section at a display time, the display time in relationship to the sequencing of the display controller;

c) determining a timing differential based on a record of the received time and the display time; and

d) communicating to the host computer a timing requirement for a future display update section based on the timing differential.

2. The method of claim 1 further comprising:

receiving a second display update section based on adjusted host timing related to the timing differential.

3. The method of claim 1, wherein the display controller manages a sequence of data to be displayed, the sequence having a plurality of sections, wherein the display update section is associated with a sequence position, wherein the display time is derived from a difference between a data sequence position maintained by the display controller at a time the display update section is received and a data sequence position of the display update section.

4. The method of claim 1 further comprising adjusting the time differential based on historical values of received time.

5. The method of claim 1 further comprising repeating steps a), b) c), and d) for a plurality of display update sections to form a display image.

6. The method of claim 5 further comprising adjusting the time differential based on historical values of received time.

7. A method of a host computer managing display updates for a remote computer, the remote computer in communication with the host computer over a network, the method comprising:

a) communicating, to the remote computer, a display update section at a first time;

b) receiving, from the remote computer, timing information, the timing information associated with a time difference between the remote computer receiving the display update section and the remote computer displaying the display update section; and

c) communicating, to the remote computer, a second display update section at a second time adjusted in accordance with the timing information.

8. The method of claim 7 further comprising repeating steps a), b) and c) for a plurality of display update sections to form a display image at the remote computer.

9. The method of claim 7 further comprising receiving a request for the remote display update, where the request comprises the timing information.

10. Apparatus for encoding display images, comprising:

an encoding sequencer for generating encoding timing in response to display timing information received from a remote display decoder;

a memory for storing a display image;

a display encoder coupled to the encoding sequencer and the memory for reading sections of the display image in the memory in response to the encoding timing received from the encoding sequencer and for encoding the display image sections; and

a network controller, in communication with the display encoder, for communicating the encoded display image sections to the remote display decoder over a network.

11. The apparatus of claim 10 wherein the network controller receives requests from the remote display decoder, where the requests include the display timing information.

12. The apparatus of claim 10 wherein the encoding sequencer emulates a display controller by generating synchronization signals for a drawing processor.

13. Apparatus for decoding and displaying computer images, comprising:

an image decoder for receiving at least one section of a display image from a host computer across a network, and for decoding the at least one section of the display image to form at least one decoded section;

a memory, coupled to the image decoder, for storing the at least one decoded section;

a display controller, in communication with the memory, for generating a raster signal comprising the at least one decoded section; and

a decoder timing module, coupled to the display controller and the image decoder, for determining a receive time for the at least one section of the display image from the host computer and a display time for the raster signal, and wherein the decoder timing module is enabled to issue requests to the host computer to adjust timing of future sections of the display image according to a difference between the receive time and the display time.

14. The apparatus of claim 13 wherein the difference is further based upon historical values of the receive time.