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Microsoft DirectStorage 1.4 Brings Quicker Load Times and Smoother Asset Streaming

To push Zstd even further, Microsoft has developed the Game Asset Conditioning Library (GACL), a companion tool that developers run on their assets before a game ships. The idea is that instead of simply compressing textures, GACL first conditions them to be more compressible, allowing Zstd to squeeze files down by up to 50% more than it otherwise could. It does this through a few different techniques. Shuffling rearranges data inside texture files so repeating patterns cluster together, giving Zstd more to latch onto. Block-Level Entropy Reduction (BLER) and Component-Level Entropy Reduction (CLER) then reduce texture complexity at the block and color-channel level, using perceptual quality as a guide so any changes remain invisible to the player. CLER takes this a step further by incorporating machine learning to identify exactly where that reduction can be applied without anyone noticing.
The good news for developers is that none of this conditioning sticks around at runtime. GACL and DirectStorage are designed as a pair, and DirectStorage automatically reverses any transforms applied during conditioning the moment an asset is decompressed. The GPU receives a clean, standard texture every time, and the game engine never has to think about any of it. The public preview available today covers BC1, BC3, BC4, and BC5 textures via DirectStorage 1.4, with BC7 support and additional performance improvements coming in a future release.











