MetalGoose

GPU-accelerated upscaling and frame generation for macOS

Features • Installation • Usage • Requirements • Building • License

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Overview

MetalGoose captures a window with ScreenCaptureKit, runs MetalFX spatial upscaling and frame generation over the captured frames, and presents the result in a borderless overlay pinned to the source window. It works on any window, not only games — anything that renders faster than it is being watched.

Features

MGUP-1 Upscaling

• MetalFX Spatial upscaling with three quality profiles:
  • Performance — Fastest upscaling with minimal latency
  • Balanced — Optimal quality/performance ratio
  • Ultra — Maximum visual fidelity
• Multiple render scales: Native, 75%, 67%, 50%, 33%
• Contrast-adaptive sharpening (CAS)

MGFG-1 Frame Generation

• MetalFX Frame Interpolation — generates one intermediate frame between two captured frames (2x output)
• Scene-cut detection to avoid interpolating across hard cuts (falls back to passthrough)
• Output frame rate is snapped to a divisor of the display refresh rate

Anti-Aliasing

Post-process anti-aliasing that runs on the final captured image, with no need for depth buffers or motion vectors:

• FXAA — Fast approximate anti-aliasing (relative edge threshold + subpixel pass)
• SMAA — Subpixel morphological AA with local contrast adaptation

Performance Monitoring

A HUD overlay reports, live:

• Capture / Output / Generated / Unique frame rates
• Capture time, GPU time, and the latency the pipeline adds before present
• VRAM, process memory, and CPU
• Cumulative counters, where Gen Presents + Passthrough = Presented

Requirements

Component	Requirement
macOS	26.5 (Tahoe) or later
Chip	Apple Silicon (M1/M2/M3/M4)
Xcode	26.6 or later (macOS 26.5 SDK)
Swift	6.3 toolchain, Swift 6 language mode
RAM	8 GB minimum, 16 GB recommended

Installation

Download Release

1. Download the latest release from Releases
2. Move MetalGoose.app to /Applications
3. Open Terminal and type xattr -dr com.apple.quarantine /Applications/MetalGoose.app
4. Grant Screen Recording and Accessibility permissions when prompted

Build from Source

git clone https://github.com/Stallion77RepoOfficial/MetalGoose
cd MetalGoose
open MetalGoose.xcodeproj

Usage

1. Launch MetalGoose and grant Screen Recording and Accessibility access.
2. Configure upscaling (MGUP-1), frame generation (MGFG-1), and anti-aliasing.
3. Switch to the window you want to capture — it has to be frontmost, since MetalGoose targets whichever app is in front when scaling starts.
4. Press ⌘⇧T, or return to MetalGoose and click Start Scaling.

Keyboard Shortcuts

Shortcut	Action
⌘ + ⇧ + T	Start or stop scaling
⌘ + ⇧ + C	Show or hide the cursor sprite

Both are global and outlive the main window, so closing it with ⌘W leaves the overlay running and ⌘⇧T still stops it.

Error Codes

All error codes are shown as an in-app alert.

UI (MG-UI)

• MG-UI-001: Frontmost app is MetalGoose; user must switch to target window.
• MG-UI-002: Target window not found for the selected app.
• MG-UI-003: Target window bounds unavailable.
• MG-UI-004: No display found.
• MG-UI-005: Display ID not found for target screen.

Capture (MG-CAP)

• MG-CAP-001: Target window not found by ScreenCaptureKit.
• MG-CAP-002: ScreenCaptureKit start error.
• MG-CAP-003: ScreenCaptureKit stop error.
• MG-CAP-004: Stream stopped with error.
• MG-CAP-005: Target entered macOS fullscreen — use windowed or borderless (windowed fullscreen) mode.
• MG-CAP-007: Capture reconfiguration failed when applying a new render scale.

Engine (MG-ENG)

• MG-ENG-001: Metal pipeline setup failed.
• MG-ENG-002: Metal device not available.
• MG-ENG-003: Metal command queue not available.
• MG-ENG-004: MetalFX Spatial Scaler creation failed.
• MG-ENG-005: Anti-aliasing pipeline unavailable.
• MG-ENG-007: CAS pipeline unavailable.
• MG-ENG-008: IOSurface texture creation failed.
• MG-ENG-009: Copy pipeline unavailable.
• MG-ENG-010: MetalFX Frame Interpolator creation failed.
• MG-ENG-011: Cursor pipeline setup failed.

Overlay (MG-OV)

• MG-OV-001: Target screen missing for overlay creation.
• MG-OV-002: Window frame missing for overlay creation.

License

This project is licensed under the GNU General Public License v3.0 - see the LICENSE file for details.

_{Built with ❤️ using Metal for macOS}

## References

Apple documentation this project was built against:

• Metal and compute passes
• MetalFX — spatial scaling and frame interpolation
• ScreenCaptureKit and capturing screen content in macOS
• MTLTexture and CVPixelBuffer — the IOSurface-backed path between capture and render
• CADisplayLink — the frame clock the pacing loop runs on
• AppKit — the overlay window