Variable-width differential memory compression

Patent metadata

Field	Value
Publication number	US-9607407-B2
Application number	US-201213732313-A
Country	US
Kind code	B2
Filing date	Dec 31, 2012
Priority date	Dec 31, 2012
Publication date	Mar 28, 2017
Grant date	Mar 28, 2017

Abstract

A method, in one embodiment, can include performing difference transformation of image samples. In addition, the method can also include performing length selection. Furthermore; the method can include performing packing that includes utilizing varying sized bit fields to produce a compressed representation.

First claim

What is claimed is:

1. A method comprising:
a graphics processor performing difference transformation of image samples;
said graphics processor performing length selection; and
said graphics processor performing packing that comprises utilizing varying sized bit fields to produce a compression representation that comprises a first and second compressed representations, said first compressed representation is packed with its bit fields descending from a first end of said compression representation and said second compressed representation is packed with its bit fields ascending from a second end of said compression representation.

2. The method of claim 1 , wherein said performing packing comprises using a lowest channel size.

3. The method of claim 1 , further comprising:
said graphics processor performing channel decorrelation of image color channels.

4. The method of claim 1 , wherein said performing length selection comprising determining raw length of each difference of said performing difference transformation of image samples.

5. The method of claim 1 , wherein said performing length selection comprising determining maximum lengths of differences for a pair of samples.

6. The method of claim 1 , wherein said performing length selection comprising determining total size of differences and lengths in a channel using lengths by pairs.

7. The method of claim 1 , wherein said performing length selection comprising determining total size of all differences and lengths in a channel using a maximum length.

8. A system comprising:
a graphics processor;
a frame buffer coupled to said graphics processor;
said graphics processor for performing a method comprising:
performing difference transformation of image samples;
performing length selection; and
performing packing that comprises utilizing varying sized bit fields to produce a compression representation that comprises a first and second compressed representations, said first compressed representation is packed with its bit fields descending from a first end of said compression representation and said second compressed representation is packed with its bit fields ascending from a second end of said compression representation.

9. The system of claim 8 , wherein said method further comprising:
performing a success check of a portion of an image.

10. The system of claim 8 , wherein said image samples were compressed before said performing difference transformation.

11. The system of claim 8 , wherein said performing length selection further comprises length index encoding.

12. The system of claim 8 , wherein said performing length selection further comprises performing alpha uniform encoding.

13. The system of claim 8 , wherein said performing packing further comprises encoding a fast-clear.

14. The system of claim 8 , wherein said image samples include data selected from a group consisting of color, depth, and stencil.

15. A method comprising:
a graphics processor performing difference transformation of image samples;
said graphics processor performing length selection which comprises performing length encoding; and
said graphics processor performing packing that comprises utilizing varying sized bit fields to produce a compression representation that comprises a first and second compressed representations, said first compressed representation is packed with its bit fields descending from a first end of said compression representation and said second compressed representation is packed with its bit fields ascending from a second end of said compression representation.

16. The method of claim 15 , wherein said performing packing further comprises using a bit field to describe an anchor sample's packing.

17. The method of claim 15 , further comprising:
said graphics processor performing channel decorrelation of image color channels.

18. The method of claim 17 , wherein said performing length selection further comprises using a single maximum length for just red and blue channels.

19. The method of claim 15 , wherein said performing length selection further comprises using a single maximum length for just red, green, and blue channels.

20. The method of claim 15 , wherein said performing packing further comprises a field to describe which fixed length set to use.

Assignees

• Nvidia Corp

Inventors

• Dunaisky Jonathan
• Mcallister David Kirk
• Mcknight William Craig

Classifications

• H04N19/426

  using memory downsizing methods · CPC title

• G06T9/00 Primary

  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 title