Texture Compression

KTX

• https://www.khronos.org/ktx/
• KTX (Khronos Texture) is an efficient, lightweight container format for reliably distributing GPU textures to diverse platforms and applications.
• The contents of a KTX file can range from a simple base-level 2D texture to a cubemap array texture with mipmaps.
• KTX files hold all the parameters needed for efficient texture loading into 3D APIs such as OpenGL® and Vulkan®, including access to individual mipmap levels
• KTX 2.0 adds support for Basis Universal supercompressed GPU textures
• Khronos has released the KHR_texture_basisu extension that enables glTF to contain KTX 2.0 textures, resulting in universally distributable glTF assets that reduce download size and use natively supported texture formats to reduce GPU memory size and boost rendering speed on diverse devices and platforms.

Basis Universal

• https://github.com/BinomialLLC/basis_universal
• Basis Universal is a "supercompressed" GPU texture data interchange system

• Supports two highly compressed intermediate file formats

• .basis

• .KTX2 open standard from the Khronos Group
• Can be quickly transcoded to a very wide variety of GPU compressed and uncompressed pixel format

• Supports two modes

• UASTC

  • high quality mode
  • based off the UASTC compressed texture format
  • for extremely high quality (similar to BC7 quality)
• ETC1S
  • lower quality mode
  • based off a subset of ETC1
  • for very small files