Drop-in compatibility shim for applications built against older NVIDIA NVENC SDK versions (e.g. SDK 6.0) that no longer work with modern drivers (R550+).

NVIDIA R550+ drivers removed support for legacy NVENC presets and rate control modes. Applications compiled against older SDKs fail at runtime with UNSUPPORTED_PARAM or INVALID_VERSION errors.

This shim intercepts NVENC API calls and transparently:

• Translates deprecated presets (e.g. LOW_LATENCY_HQ) to the new P1–P7 preset system with appropriate tuningInfo
• Converts removed rate control modes (CBR_HQ, VBR_HQ, CBR_LOWDELAY_HQ) to their modern equivalents with multi-pass encoding
• Patches struct versions and API version fields to match the current driver
• Zeroes out reserved fields that changed meaning between SDK generations

No modifications to the target application are needed.

Requires Visual Studio or Build Tools.

cd nvenc_shim
build.bat

Outputs:

• build/release/nvEncodeAPI64.dll — no logging
• build/debug/nvEncodeAPI64.dll — logs all intercepted calls to nvenc_shim.log

Copy nvEncodeAPI64.dll into the application directory and run normally. Windows loads DLLs from the application directory before System32, so the shim is picked up automatically.