Color distribution for texture and image compression

• US 7,397,946 B2
• Filed: 01/23/2004
• Issued: 07/08/2008
• Est. Priority Date: 06/30/2000
• Status: Expired due to Term

• Current Assignee: Beijing Xiaomi Mobile Software Co., Ltd. (Xiaomi Corp.)
• Original Assignee: Intel Corporation
• Inventors: Ivanoy, Denis, Reshetov, Alexander, Kuzmin, Yevgeniy
• Primary Examiner(s): SHERALI, ISHRAT I
• Application Number:
  US10/764,314
• Publication Number:
  US 20040151372A1
• Time in Patent Office: 1,628 Days
• Field of Search: 382162-167, 382232-253, 358/119, 358/575, 358/539, 345501-503, 345/552, 345/555, 345/587, 345/582, 345/597
• US Class Current: 382/166
• CPC Class Codes: G06T 11/001 Texturing; Colouring; Generation of texture or colour inpainting G06T5/77
• CPC Class Codes: G06T 9/005 Statistical coding, e.g. Huffman, run length coding
• CPC Class Codes: H04N 1/644 using a reduced set of representative colours, e.g. each representing a particular range in a colour space

Abstract

A block decomposition based method is provided for compressing textures based on sharing color information between texture blocks. The texture map is divided into a plurality of texture blocks containing texels. During compression a first color value is stored for a first block and a second color value is stored for a second block. A palette is created for each texture block using the color values stored for several neighboring texture blocks. Each texel in each of the texture blocks is indexed to one of the colors in the palette. Accordingly the method compresses the information in the texture map by storing for each texture block bits representing a color value and bits to index each of the texels to a color in the palette, which allows sharing of color information between blocks. During decompression the palettes are regenerated and colors from the palette are assigned to the texels according to the stored index values. Accordingly, the decompression of the texture allows regeneration of the compressed texture, which may be mapped to surfaces to improve the visual quality of three-dimensional graphics.

Claims

1. A method comprising, for each of a plurality of blocks in an image, generating compressed information including information representing a single color value and information representing a plurality of color palette indices including at least one color palette index to a color represented in compressed information for another block in the image.

2. The method of claim 1, wherein the blocks comprise texture blocks, the image includes a texture, and the compressed information includes compressed texture information.

3. The method of claim 2, wherein generating the compressed texture information is done without determining sequences of repeating elements.

4. The method of claim 2, wherein the plurality of texture blocks comprise a plurality of 4×

4 texel blocks.

5. A computer-readable medium having stored thereon data representing sequences of computer instructions that when executed cause a machine to:

generate compressed texture information for a first block in a texture, the compressed texture information including information representing a single color value and information representing a plurality of color palette indices, at least one of the plurality of color palette indices corresponding to a color value associated with a second block in the texture.

6. A method comprising:

dividing a texture into a plurality of non-overlapping texture blocks including a first texture block and a second texture block;

determining a color palette for the first texture block, the color palette including a plurality of color values including at least one color value stored for the second texture block; and

compressing the first texture block by determining indices for a plurality of texels in the first texture block to color values in the color palette and storing compressed texture information which includes these indices.

7. The method of claim 6, wherein the color palette further comprises a color value stored for the first texture block.

8. The method of claim 7, wherein the color palette further comprises a second color value stored for the first texture block.

9. The method of claim 6, wherein determining the color palette further comprises calculating a difference between an uncompressed texel color value and a color value in the color palette for that texture block, and reducing the difference by changing the color value to be stored for the second texture block.

10. The method of claim 6, wherein the texture comprises a plurality of two-dimensional textures and the first texture block is contained in one of the two-dimensional textures.

11. A computer system comprising:

a bus;

a memory coupled to the bus;

a network interface device coupled to the bus;

a processor coupled to the bus; and

computer instructions stored on a computer-readable medium that when executed cause the processor to generate compressed texture information for a block in an image, the compressed texture information including information representing a single color value and information representing a plurality of color palette indices including an index to a color value associated with another block in the image.