# Upscayl — Free Open-Source AI Image Upscaler > A cross-platform desktop application that uses AI models to upscale and enhance images locally without sending data to the cloud. ## Install Save as a script file and run: # Upscayl — Free Open-Source AI Image Upscaler ## Quick Use ```bash # Linux (Flatpak) flatpak install flathub org.upscayl.Upscayl # macOS brew install --cask upscayl # Windows — download the installer from GitHub Releases # Then: open Upscayl, drop an image, pick a model, click Upscale ``` ## Introduction Upscayl is a free, open-source desktop application that upscales images using AI super-resolution models. It runs entirely on your local machine using Vulkan-based GPU acceleration, so your images never leave your device. Upscayl supports Linux, macOS, and Windows. ## What Upscayl Does - Upscales images by 2x, 3x, or 4x using AI super-resolution models - Processes single images or entire folders in batch mode - Runs inference locally using Real-ESRGAN and other NCNN-based models - Provides a before-and-after comparison slider for quality review - Exports results in PNG, JPG, or WebP formats ## Architecture Overview Upscayl is built with Electron for the desktop shell and uses Real-ESRGAN-ncnn-vulkan as the inference backend. The Vulkan-based compute pipeline runs on most GPUs across vendors (NVIDIA, AMD, Intel) without requiring CUDA. The application spawns the upscaling binary as a child process, streaming progress updates back to the UI. ## Self-Hosting & Configuration - Install from Flatpak, Homebrew, or the GitHub Releases page - Select from built-in models or load custom NCNN models - Configure output format, scale factor, and compression quality - Set a default output directory for processed images - Adjust GPU thread count for performance tuning on multi-GPU systems ## Key Features - No cloud dependency — all processing happens on-device - Vulkan backend works across NVIDIA, AMD, and Intel GPUs - Batch upscaling for processing entire directories at once - Support for custom models in NCNN format - Built-in comparison view to inspect upscale quality ## Comparison with Similar Tools - **Topaz Gigapixel AI** — commercial and paid; Upscayl is completely free and open source - **waifu2x** — older model architecture; Upscayl uses newer Real-ESRGAN models with better results - **Real-ESRGAN CLI** — command-line only; Upscayl wraps it in a user-friendly desktop GUI - **ChaiNNer** — node-based image processing; Upscayl is simpler for one-click upscaling ## FAQ **Q: Does Upscayl require a dedicated GPU?** A: A Vulkan-compatible GPU is strongly recommended. CPU-only mode exists but is very slow. **Q: What image formats does Upscayl support?** A: Input supports PNG, JPG, WebP, and AVIF. Output can be PNG, JPG, or WebP. **Q: Can I add custom AI models?** A: Yes. Place NCNN-format model files in the custom models directory and they appear in the model selector. **Q: How large can input images be?** A: It depends on GPU VRAM. For images larger than 4K, Upscayl automatically tiles the image to fit available memory. ## Sources - https://github.com/upscayl/upscayl - https://upscayl.org --- Source: https://tokrepo.com/en/workflows/asset-56b0779f Author: Script Depot