Graphic codec for network transmission

• US 20060182354A1
• Filed: 04/11/2006
• Published: 08/17/2006
• Est. Priority Date: 01/31/2003
• Status: Active Grant

• Current Assignee: Ryuichi Iwamura
• Original Assignee: Ryuichi Iwamura
• Inventors: Iwamura, Ryuichi
• Granted Patent: US 7,376,278 B2
• Time in Patent Office: Days
• US Class Current: 382/232
• 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 2320/106 Determination of movement vectors or equivalent parameters within the image
• CPC Class Codes: G09G 2340/02 Handling of images in compressed format, e.g. JPEG, MPEG
• CPC Class Codes: G09G 2358/00 Arrangements for display data security
• CPC Class Codes: G09G 2370/022 Centralised management of display operation, e.g. in a server instead of locally
• CPC Class Codes: H04N 19/107 between spatial and temporal predictive coding, e.g. picture refresh
• CPC Class Codes: H04N 19/137 Motion inside a coding unit, e.g. average field, frame or block difference
• CPC Class Codes: H04N 19/176 the region being a block, e.g. a macroblock
• CPC Class Codes: H04N 19/51 Motion estimation or motion compensation
• 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 19/61 in combination with predictive coding

Abstract

Various embodiments of the invention provide a method, system, and apparatus for transmitting screen display information from a remote server to a client. One embodiment features a video decoder that comprises (i) an input port to receive data that includes a data identifier to distinguish between a first data type and a second data type, (ii) a loss-less decoder, and (iii) a lossy decoder. The loss-less decoder is coupled to the data identifier and receives and decodes data of the first data type from the data identifier. The lossy decoder is coupled to the data identifier and receives and decodes data of the second data type from the data identifier.

Claims

1. A method comprising:

encoding a first block of graphics data using a lossy encoding scheme;

encoding a second block of graphics data using a loss-less encoding scheme; and

transmitting the first and second block of graphics data from an encoder for subsequent decoding and use.

2. The method of claim 1 wherein the first and second blocks of graphics data occur in a first display frame.

3. The method of claim 1 wherein the first block of graphics data changes more frequently than the second block of graphics data.

4. The method of claim 1 wherein the first block of graphics data is display graphics data encoded using Moving Picture Experts Group (MPEG) encoding and the second block of graphics data is display graphics data encoded using Differential Pulse Code Modulation (DPCM) encoding.

5. The method of claim 1 wherein encoding the second block of graphics data includes employing intra-frame block matching.

6. The method of claim 5 wherein intra-frame block matching includes,

determining if the first block may be matched to a neighboring block in the same display frame,

determining if the first block may be matched to other blocks within a certain region of the same display frame if no matching block is found in the neighboring blocks, and

sending information identifying a matching block instead of the actual first block if a matching block is found.

7. The method of claim 6 wherein, if no matching block is found, the method comprises:

selecting a third block that closely matches the first block in the same display frame, the third block closely matches the first block if both the third block and the first block have a minimum threshold of identically matching pixels; and

sending a vector identifying the third block as well as all dissimilar information between the first block and the third block to a decoder.

8. The method of claim 6 wherein, if no matching block is found, then the first block is encoded using the loss-less encoding scheme and the encoded information is sent to a decoder.

9. The method of claim 5 further comprising:

receiving motion information, utilizing the motion information to estimate a matching block.

10. The method of claim 1 wherein encoding the second block of graphics data comprises employing inter-frame block matching.

11. The method of claim 1, wherein the method is performed by software executed by a processor.

12. A video decoder comprising:

an input port to receive data;

a data identifier to distinguish between a first data type and a second data type;

a loss-less decoder coupled to the data identifier, the loss-less decoder to receive and decode data of the first data type from the data identifier; and

a lossy decoder coupled to the data identifier, the lossy decoder to receive and decode data of the second data type from the data identifier.

13. The video decoder of claim 12 wherein the first and second data types are graphical data types occurring in a first display frame.

14. The video decoder of claim 12 wherein the second data type is graphics data which changes more frequently than the first data type.

15. The video decoder of claim 12 further comprising:

a multiplexer coupled to receive data from the input port, and send the received data to either the lossy decoder or the loss-less decoder depending on the data type identified.

16. The video decoder of claim 12 wherein, the data identifier determines the type of encoding employed on a first block, and

reconstructs the first block based on current frame information if intra-frame encoding was employed,

reconstructs the first block based on previous frame information if inter-frame encoding was employed,

reconstructs the first block base on a combination of a second closely matched block in the current frame and dissimilar information between the first block and the second block, if a closely matched block was received, and

reconstructs the first block by decoding all the received data if no matching block was identified.

17. The video decoder of claim 16 further includes

one or more frame memories, one of the one or more frame memories to store an earlier frame.

18. A video decoder comprising:

means for distinguishing between data of a first data type and a second data type;

a loss-less decoder to receive and decode data of the first data type; and

a lossy decoder to receive and decode data of the second data type.

19. The video decoder of claim 18 wherein the first and second data types are data blocks occurring in a first display frame.

20. The video decoder of claim 18 wherein the second data type is graphics data that changes more frequently than the first data type.

21. The video decoder of claim 20 further comprising:

an input port to receive the data; and

a multiplexer coupled to receive the data from the input port and to send the received data to the lossy decoder if the data is of the second data type or to the loss-less decoder if the data is of the first data type.

22. The video decoder of claim 18 wherein the lossy decoder comprises:

a first variable length decoder;

an inverse quantizer (IQ) coupled to the variable length decoder; and

an inverse discrete cosine transformer (IDCT) coupled to the IQ.

23. The video decoder of claim 22 wherein the loss-less decoder comprises:

a second variable length decoder; and

a Differential Pulse Code Modulation (DPCM) decoder.

24. The video decoder of claim 18 further comprising an adder;

and

a first switch selectively coupling either the lossy decoder to the adder or the loss-less decoder to the adder.

25. The video decoder of claim 24 further comprising a motion compensator (MC) selectively coupled to the adder when the first switch is coupled to the lossy decoder.

26. The video decoder of claim 18 being implemented within a device with display, input capabilities for receipt of the data and storage capabilities.