Hans-Kristian Arntzen, the developer behind VKD3D-Proton, has built Valve a new video codec called Pyrowave that trades bandwidth efficiency for extremely low latency in Steam Remote Play. The experimental codec landed in today's Steam client beta across Windows, macOS, and Linux, with the Linux version requiring the experimental SteamRT3 client. Arntzen's involvement is notable given that VKD3D-Proton, his Direct3D 12 to Vulkan translation layer, is one of the foundational pieces that makes Windows gaming on Linux possible through Proton.
Pyrowave is built on the Vulkan API and consumes roughly 5 to 10 times the bandwidth of conventional streaming codecs like H.264 or HEVC. That makes it impractical over the internet but potentially transformative on a local network. Valve recommends at least Gigabit Ethernet, which positions Pyrowave squarely as a LAN streaming solution for setups where a gaming PC drives a secondary device in another room. The codec supports HDR and YUV 4:4:4 chroma subsampling, preserving full color information rather than the reduced 4:2:0 subsampling that most game streaming services use. For text readability, desktop use, and color-accurate content, 4:4:4 is a meaningful upgrade.
The approach reflects a different philosophy from competing streaming technologies like Moonlight and Sunshine, which optimize for minimal bandwidth and internet-viable latency. Pyrowave instead assumes abundant local bandwidth and prioritizes the encode-decode round trip above all else. Users who have wired their Steam Deck, a mini PC, or a living room box into the same network as their gaming rig stand to benefit most. The codec can be enabled now through Steam Remote Play's advanced client settings.