eise.app - Browser-Based Planetary Image Stacker

https://eise.app is the first fully browser-based planetary image stacking tool. Everything runs locally on your machine using WebAssembly and Web Workers - your data never leaves your computer.

The name is an ode to Eise Eisinga, a Frisian amateur astronomer who built a planetarium in his living room. The project started from frustrations getting existing software running on ARM-based Macs - AutoStakkert4! didn't work in Wine, PSS had dependency issues, Lynkeos crashed continuously.

How it works

1. Load your capture - Select a SER file (recommended), AVI, or any video format
2. Frame ranking - Sharpness analysis scores each frame using Laplacian variance
3. Quality selection - Choose which percentage of frames to stack with an interactive quality graph
4. Auto-crop - Detects and centers the target in each frame, rejects cut-off frames
5. Local alignment - Alignment Points (APs) track motion across the frame using template matching
6. De-warping - Displacement maps correct atmospheric wobble using inverse distance weighted interpolation
7. Stacking - Quality-weighted averaging with optional 1.5x drizzle
8. Post-processing - Wavelet sharpening, deconvolution, RGB alignment, rotation, crop

All processing happens client-side using WebGPU (GPU-accelerated) or falls back to CPU via OpenCV WebAssembly.

Features

• 100% browser-based - No uploads, no installs, works on any OS
• File support - SER (recommended), AVI (uncompressed), or any video via FFmpeg.js
• Surface mode - For Moon/Sun closeups with drift tracking
• Drizzle - 1.5x output resolution using sub-pixel frame offsets
• WebGPU acceleration - Fast GPU-based template matching and stacking

Acknowledgments

This project draws inspiration from Planetary System Stacker by Rolf Hempel. The alignment point approach, local de-warping, and quality-weighted stacking concepts are based on PSS's implementation.

Running locally

git clone https://github.com/tijmen/eise.app
cd eise.app
npm install
npm run dev

Browser requirements

eise.app uses WebGPU for fast GPU-accelerated processing:

• Chrome 113+ (Android: 121+)
• Edge 113+
• Safari 18+ (macOS Sequoia / iOS 18)
• Firefox 141+ (Windows only for now)

Falls back to CPU processing on older browsers.

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Happy Stacking, Tijmen