(Updated 2020-05-27)
etcpak is an extremely fast Ericsson Texture Compression and S3 Texture Compression (DXT1/DXT5) utility. Currently it's best suited for rapid assets preparation during development, when graphics quality is not a concern, but it's also used in production builds of applications used by millions of people.
Benchmark performed on an AMD Ryzen 9 3900X, using a real-life RGBA 16K × 16K atlas. Tests were performed using a single CPU core.
ETC1: 370.3 Mpx/s
ETC1 + dithering: 278.8 Mpx/s
ETC1 alpha: 568.1 Mpx/s
ETC2 RGB: 188.6 Mpx/s
ETC2 RGBA: 140.8 Mpx/s
DXT1: 2372 Mpx/s
DXT5: 1167 Mps/s
ARM benchmark performed on Odroid C2, using the same atlas:
ETC1: 23.6 Mpx/s
ETC1 + dithering: 23.4 Mpx/s
ETC1 alpha: 36.6 Mpx/s
ETC2 RGB: 12.1 Mpx/s
ETC2 RGBA: 2.83 Mpx/s
DXT1: 120.2 Mpx/s
DXT5: 83.3 Mps/s
Why there's no image quality metrics? / Quality comparison.
etcpak can also decompress ETC1, ETC2 (no T or H blocks), DXT1 and DXT5 textures. Timings on Ryzen:
ETC1: 332.5 Mpx/s
ETC2 RGB: 470.1 Mpx/s
ETC2 RGBA: 340.8 Mpx/s
DXT1: 682.7 Mpx/s
DXT5: 518.9 Mpx/s
ARM timings:
ETC1: 60 Mpx/s
ETC2 RGB: 88.5 Mpx/s
ETC2 RGBA: 64.2 Mpx/s
DXT1: 120.2 Mpx/s
DXT5: 83.3 Mpx/s
To give some perspective here, Nvidia in-driver ETC2 decoder can do only 42.5 Mpx/s.
Original image:
Compressed image:
ETC1:
etcpak 0.6
etcpak 0.5
etcpak 0.4
etcpak 0.3
etcpak 0.2.2
etcpak 0.2.1
etcpak 0.2
etcpak 0.1