From dd0380219c9f37e74c9419c19a93ab014d110772 Mon Sep 17 00:00:00 2001 From: Rich Geldreich Date: Mon, 29 Apr 2019 19:15:18 -0700 Subject: [PATCH] Update readme --- README.md | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/README.md b/README.md index e3d9a8a..3889816 100644 --- a/README.md +++ b/README.md @@ -1,5 +1,23 @@ # basis_universal Basis Universal GPU Texture Compressor +So far, we've compiled this using MSVS 2019, and under Ubuntu using cmake with either clang 3.8 or gcc 5.4. +The command line tool is named "basisu". Run basisu without any parameters for help. + +To compress an sRGB image to .basis: + +basisu -srgb x.png + +Note that basisu defaults to linear colorspace metrics, not sRGB. If the input is a photograph, or a diffuse/albedo/specular/etc. texture, you want to use sRGB for much better rate distortion performance. + +To unpack a .basis file to .png/.ktx files: + +basisu x.basis + +The mipmapped .KTX files will be in a variety of GPU formats (PVRTC1 4bpp, ETC1-2, BC1-5, BC7), and to my knowledge there is no single .KTX viewer tool that supports every GPU texture format. BC1-5 and BC7 files are viewable using AMD's Compressonator, ETC1/2 using Mali's Texture Compression Tool, and PVRTC1 using Imagination Tech's PVRTexTool. Links: + +https://duckduckgo.com/?q=mali+texture+compression+tool&atb=v146-1&ia=web +https://gpuopen.com/gaming-product/compressonator/ +https://www.imgtec.com/developers/powervr-sdk-tools/pvrtextool/