Scythe (WIP)

High-performance, zero-copy GPU hardware screen recorder and instant replay overlay for Linux (Wayland & X11) and Windows.

Scythe is a native, ultra-lightweight alternative to NVIDIA ShadowPlay and GPU Screen Recorder. It records gameplay and desktop screens with near-zero CPU and GPU overhead by leveraging hardware video acceleration and zero-copy direct memory pipelines.

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Features

• Instant Replay Buffer: Constantly records gameplay into a high-speed in-memory circular ring buffer. Save the last 15s to 5 minutes of action instantly with one hotkey (Ctrl+Shift+R) without writing temporary files to disk.
• Zero-Copy Capture Engine:
  • Wayland: PipeWire DMA-BUF frame-passing directly to hardware encoder surfaces.
  • X11: XCB Shared Memory (MIT-SHM) capture with per-frame pool reuse.
  • Windows: Desktop Duplication API via Direct3D 11 (DXGI) texture binding.
• Hardware-Accelerated Encoding:
  • NVIDIA NVENC (h264_nvenc, hevc_nvenc, av1_nvenc) with direct hardware BGR0 input
  • AMD AMF (h264_amf, hevc_amf, av1_amf) with native hardware format support
  • Intel QuickSync (h264_qsv, hevc_qsv, av1_qsv)
  • AMD & Intel VAAPI (h264_vaapi, hevc_vaapi, av1_vaapi) with DMA-BUF zero-copy
  • Universal SIMD-accelerated CPU fallback (libx264, libx265, libsvtav1)
• ShadowPlay-Style Stealth Overlay:
  • Native GTK 3 Layer-Shell overlay with real background blur for Wayland compositors (Hyprland, Sway, etc.).
  • Cross-platform hardware-rendered egui overlay for Windows, GNOME, KDE, and X11.
  • Translucent frosted glass HUD dock, centered controls, and contextual dropdowns.
• Dynamic Hyprland Integration: Automatically registers overlay blur rules and binds hotkeys at runtime without modifying hyprland.conf.
• Multi-Channel Audio Routing: Record system audio, microphone, or both simultaneously with individual volume controls via native PulseAudio/PipeWire and WASAPI/CPAL.

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Default Shortcuts

Action	Shortcut	CLI Command
Open / Close HUD Overlay	Alt + Z	scythe --menu
Save Instant Replay	Ctrl + Shift + R	scythe --save
Toggle Normal Recording	Ctrl + Shift + F9	scythe --record
Toggle Mouse Cursor	Ctrl + Shift + F10	scythe --cursor
Take Screenshot	Ctrl + Shift + S	scythe --screenshot

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Installation

Arch Linux (AUR)

git clone https://aur.archlinux.org/scythe-git.git
cd scythe-git
makepkg -si

Pre-Built Packages (Releases)

Download the latest packages directly from GitHub Releases or Forgejo Releases:

• Windows Setup: scythe-setup.exe (Official installer with Start Menu & Desktop shortcuts)
• Windows Portable: scythe.exe (Standalone self-contained executable) & scythe-windows-x86_64.zip
• Debian / Ubuntu / Linux Mint: scythe_*_amd64.deb
• Fedora / RHEL / openSUSE: *.rpm
• Universal Linux: scythe-x86_64.AppImage
• Generic Linux: scythe-linux-x86_64.tar.gz

Build from Source

Prerequisites

• Rust (1.85+, the crate uses the 2024 edition)
• FFmpeg 6+ / 7+ development libraries (libavcodec, libavformat, libavutil, libswresample, libswscale)
• PipeWire (libpipewire-0.3-dev)
• XCB (libxcb1-dev, libxcb-shm0-dev, libxcb-xfixes0-dev)
• ALSA (libasound2-dev)
• clang and pkg-config for the FFmpeg bindings

Compile & Install

git clone https://github.com/oiupoyt/scythe.git
cd scythe
bash install.sh

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CLI Usage

scythe --menu           # Open the interactive overlay UI menu
scythe --status         # Query background daemon state and metrics
scythe --save           # Save instant replay clip to disk
scythe --record         # Toggle normal recording on/off
scythe --cursor         # Toggle mouse cursor capture
scythe --reload         # Reload daemon settings
scythe --quit           # Stop background recording daemon

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Configuration

Settings are saved in JSON format at ~/.config/scythe/config.json:

{
  "fps": 60,
  "record_bitrate_kbps": 18000,
  "replay_duration_sec": 60,
  "video_codec": "h264",
  "output_directory": "~/Videos",
  "show_cursor": true,
  "audio_mode": "system",
  "mic_volume": 0.6,
  "system_volume": 1.0,
  "menu_hotkey": "Alt+Z",
  "save_hotkey": "Ctrl+Shift+R",
  "record_hotkey": "Ctrl+Shift+F9",
  "cursor_hotkey": "Ctrl+Shift+F10"
}

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License

Licensed under either of Apache License, Version 2.0 or MIT License at your option.