First XUASTC LDR 4x4 rate-distortion graph

ASTC GPU texture blocks form a latent image space where JPEG techniques still work. (So does BC7.)

Here's a XUASTC LDR 4x4 (arithmetic vs. Zstd profile) bit rate vs. distortion graph across 151 test textures/images (the same test corpus we used to create bc7e.ispc). Distortion was measured using PSNR-HVS-M. 

XUASTC LDR 4x4 transcodes to standard ASTC LDR 4x4 in memory/VRAM (8.0 bpp). It supports all 14 standard ASTC block sizes up to 12x12.

Open Geospatial Consortium membership

I'm now a member of the OGC:

https://www.ogc.org/

Basis Universal v2.1 library wiki mirror

It's been automatically converted to HTML and mirrored outside of GitHub here: Home.

A static mirror of the GitHub repo is here.

The KTX-Software repo has been forked

Binomial LLC has forked the Khronos Group's KTX-Software repo, to use as a staging ground for next-generation GPU texture compression technology:

https://github.com/BinomialLLC/KTX-Software-Binomial-Fork/

Degenerate but valid ASTC configs: suboptimal CEM encodings

See: 

https://github.com/BinomialLLC/basis_universal/wiki/List-of-Available-Software-ASTC-Decoders#degenerate-but-valid-astc-configs-suboptimal-cem-encoding

Updated: "ASTC GPU Texture Decoding: Software Decoders, Spec Issues, and ARM Errata"

ASTC's complexity has created an ecosystem where correctness is an ongoing research problem rather than a fully solved one. See:

https://github.com/BinomialLLC/basis_universal/wiki/List-of-Available-Software-ASTC-Decoders

.ASTC (the File Format): No Longer a Black Box

The basisu command line tool has a new option, -peek, which opens any standard ARM LDR/HDR .ASTC texture file, unpacks each block, and computes a bunch of statistics about the exact ASTC configurations the blocks used.

This is how we found out that Intel's ispc_texcomp's ASTC encoder is, for all practical purposes, broken.

https://github.com/BinomialLLC/basis_universal/wiki/Displaying-.astc-file-block-statistics-using-the-peek-command-line-option