System and method using a packetized encoded bitstream for parallel compression and decompression

• US 20050135433A1
• Filed: 01/19/2005
• Published: 06/23/2005
• Est. Priority Date: 06/18/1998
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Chang, Luke Y., Liu, John C., Fuccio, Michael L., Elder, Gordon Max
• Granted Patent: US 7,180,901 B2
• Time in Patent Office: Days
• US Class Current: 370/536
• CPC Class Codes: H04N 19/176 the region being a block, e.g. a macroblock
• CPC Class Codes: H04N 19/186 the unit being a colour or a chrominance component
• CPC Class Codes: H04N 19/436 using parallelised computational arrangements
• CPC Class Codes: H04N 19/60 using transform coding

Abstract

A system and method are disclosed for parallel compression and decompression of a bitstream. For compression, the bitstream is separated into a plurality of components, and the components are encoded using a compression algorithm. Packets are then constructed from the encoded components. At least one packet is associated with each encoded component and comprises header information and encoded data. The packets are combined into a packetized encoded bitstream. For decompression, the packets are separated from the packetized encoded bitstream using the header information. The packets are then decoded in parallel using a decompression algorithm to recover the encoded data. The plurality of components are reconstructed from the recovered encoded data and combined to-recover the bitstream.

Claims

1. A method for parallel compression and decompression of a bitstream, comprising:

separating a bitstream into a plurality of components;

encoding the components using a compression algorithm;

constructing packets from the encoded components, where at least one packet is associated with each encoded component and the at least one packet comprises header information and encoded data;

combining the packets into a packetized encoded bitstream;

separating packets from the packetized encoded bitstream using the header information;

decoding packets in parallel using a decompression algorithm to recover the encoded data;

constructing the plurality of components from the recovered encoded data; and

combining the plurality of components to recover the bitstream.

2. The method of claim 1, wherein the bitstream is a digitized graphics or video frame.

3. The method of claim 2, wherein separating the bitstream into a plurality of components comprises separating the graphics or video frame into separate lines.

4. The method of claim 2, wherein combining the plurality of components to recover the bitstream comprises recovering the digitized graphics or video frame for display.

5. The method of claim 1, wherein encoding the components using a compression algorithm comprises encoding using a lossless compression format.

6. The method of claim 1, wherein decoding packets in parallel using a decompression algorithm comprises encoding using a lossless compression format.

7. The method of claim 1, wherein constructing packets from the encoded components comprises constructing variable-length packets.

8. The method of claim 7, wherein the header information of the at least one packet comprises a size, a predictor and an alignment.

11. A system for parallel compression and decompression of a bitstream, comprising:

an encoder system comprising;

a plurality of encode units operable to receive components separated from a bitstream and to encode the components using a compression algorithm;

the encode units further operable to construct packets from the encoded components, where at least one packet is associated with each encoded component and the at least one packet comprises header information and encoded data; and

a multiplexer coupled to the encode units, the multiplexer operable to combine the packets into a packetized encoded bitstream; and

a decoder system comprising;

a feeder operable to separate packets from the packetized encoded bitstream;

a plurality of decode queues, the feeder further operable to distribute the packets to the decode queues;

a plurality of decode units each associated with one of the decode queues, the decode units operable to decode packets using a decompression algorithm to recover the encoded data and to reconstruct the components; and

a demultiplexer coupled to the plurality of decode units the demultiplexer operable to combine the plurality of components to recover the bitstream.

9. The method of claim 10, wherein the header information of the at least one packet comprises a tag.

10. The method of claim 11, wherein decoding packets in parallel comprises distributing packets to separate decode units based upon the tag.

14. The system of claim 14, wherein the demultiplexer combines the plurality of components to recover the digitized graphics or video frame for display.

12. The system of claim 13, wherein the bitstream is a digitized graphics or video frame.

13. The system of claim 14, wherein the plurality of components comprise separate lines of the digitized graphics or video frame.

15. The system of claim 13, wherein the encode units use a lossless compression format for the compression algorithm.

16. The system of claim 13, wherein the encode units construct variable-length packets.

18. The system of claim 23, wherein the header information of the at least one packet comprises a tag.

19. The system of claim 24, wherein the feeder distributes the packets to separate decode queues based upon the tag.

17. The system of claim 19, wherein the header information of the at least one packet comprises a size, a predictor and an alignment.

20. The system of claim 24, wherein the feeder comprises an input queue operable to receive the packetized encoded bitstream.