PhyriadFG

External-capture, multi-GPU frame generation. PhyriadFG runs outside the game: it captures the already-rendered output, estimates the motion between real frames, synthesizes intermediate frames, and presents them — with no access to the game engine, its motion vectors, or its depth. One executable, one build.

0.4.0-experimental · Windows · student-built, LLM-assisted.

Questions, testing feedback, and release announcements: discord.gg/x6ZsjVchs

What it is

• A frame generator that works on any game because it only sees the final image (like Lossless Scaling Frame Generation), not an in-engine FG.
• Multi-GPU by design: capture + convert on the integrated GPU, optical flow on a second GPU, warp and present on the primary GPU — each role on the device where its work pays off. It degrades to a single GPU with --force-single-gpu.
• A quality stack (occlusion / disocclusion handling, a global motion model, edge-gated picks, content- clock pacing) layered on a backward-warp + blend core.
• A Tauri launcher UI under ui/ for picking the target window and toggling flags.

Build

Requires Windows, MSVC Build Tools, the Vulkan SDK, and Ninja (included with the Build Tools). Set the VULKAN_SDK environment variable before building (the SDK installer does this automatically).

build-release.bat    ->  build-release\phyriad_fg.exe   (distributable, no debug DLLs)
build.bat            ->  build\phyriad_fg.exe            (debug build)

One target, LTO enabled on release. Both scripts detect Visual Studio automatically via vswhere.exe — no hardcoded paths.

Run

build\phyriad_fg.exe --window "Game Title"      capture the monitor that window is on (DDA), generate, present
build\phyriad_fg.exe --monitor 0                capture monitor 0
build\phyriad_fg.exe --help                     the full flag list

DDA (Desktop Duplication) is the default capture path; --capture-api wgc selects Windows Graphics Capture (window-only). The launcher UI (ui\run.bat) wraps the same flags with a target-window picker.

The intended workflow on a multi-GPU rig: the primary GPU owns the display and does the warp + present, a second GPU runs the optical flow, and the integrated GPU does the zero-copy convert.

Honest scope

• It cannot exceed the display refresh without frame injection or a display driver — it is an external overlay sharing the GPU(s) with the game.
• Interpolation adds latency. Like every external-capture FG, an intermediate frame is shown before the real frame it precedes; the cost is reported live (the lat stat). Use it for fluidity, not for competitive latency.
• No engine data. Disocclusion (newly revealed regions) is the hard case for any image-only FG; the quality layers mitigate it but cannot fully solve it.
• Built and tested on one Windows multi-GPU rig; treat hardware coverage as experimental.

Architecture

See docs/ARCHITECTURE.md for the full map, and docs/diagrams/ + docs/slides/ for the figures:

• Three pipelined threads — C (capture, iGPU) → F (optical flow, second GPU) → P (warp + present, primary GPU) — communicating through FgContext (lock-free SPSC rings).
• A central config resolver (resolve_config) that reconciles flag dependencies and owns the cross-layer predicates in one place — the single source of truth.
• A governor control word that lets the pipeline graduate down non-essential work under GPU saturation while it keeps generating.

License & attribution

Released under the MIT License — free to use, modify, and distribute. See LICENSE.

If you use PhyriadFG or any of its code, the MIT license requires you to keep the copyright notice, i.e. to credit Eduardo Ramos Mendoza (Swately). A visible mention in your project's credits, documentation, or about screen is appreciated.

© 2026 Eduardo Ramos Mendoza (Swately).