OptiScaler is an open-source, highly customizable middleware proxy library designed to run at the rendering level of PC games. It translates game-level upscaler calls and reroutes them to user-selected target upscalers and frame generation backends.
Rather than editing game binaries directly or executing external overlays that inject lag, OptiScaler acts as a native proxy library inside the game's executable path.
By renaming OptiScaler to a common graphics API DLL name (like dxgi.dll or d3d12.dll) and placing it next to the game executable, the local file is loaded with higher execution priority than system folders. OptiScaler captures device initialization and hooks system handles using Microsoft Detours.
OptiScaler captures rendering assets from the engine queue—including color buffers, camera jitter offsets, exposure textures, sub-pixel depth buffers, and temporal motion vectors. It normalizes these coordinate structures in RAM and packs them into the target API formats (AMD FSR 4, XeSS, or custom DLSS models).
To display restricted upscaling options in menus, many modern games inspect hardware specifications via DXGI adapter queries. OptiScaler intercepts these queries:
OptiScaler supports four discrete frame pacing routes:
Present) for DX12 games that lack native Frame Gen toggles.OptiScaler is maintained by a highly active open-source community under Nitec's leadership.
Developed CyberFSR2, proving translation logic.
Creator of DLSS Enabler; assisted with NVNGX API paths.
Developer of dlssg-to-fsr3, bundled natively.
Early Frame Gen modding technical insights.
Leading QA coordinator and compatibility tester.
Fixed FSR 4 watermark buffer code.
Contributed to the setup.bat installer script.
Focused on Linux Proton overrides development.
Coded the in-game anti-cheat alert GUI.
The project has evolved through several key milestones since its initial launch.
Core translation layers mature. Demonstration of upscaler translation. Introduced Contrast Adaptive Sharpening (RCAS) and temporal inputs processing algorithms.
Added initial support for OptiFG, introducing experimental swapchain-level Frame Generation for games that lack native Frame Gen toggles. Added built-in Unreal Engine quirks compatibility list.
Fully rewrote the Frame Gen settings backend. Bundled FakeNVAPI and Nukem's dlssg-to-fsr3 module directly. Integrated official AMD FFX 2.2 SDK, unlocking native FSR 4.1 upscaling and ML-FG capabilities for RDNA 4.
Focused on debugging the v0.9 branches. Resolved swapchain buffer resize and window handle crashes. Added manual input polling to resolve invisible overlays in Metro EE and STALKER, and fixed tone mapping burn-in under HDR modes.