High altitude balloon imagery decoding in the browser with C, JS, and Python
summary
Browser builds of Horus and Wenet demodulators become real: WebHorus and WebWenet compile C demod code into Python modules, build those modules to WebAssembly, and call them from JavaScript with no server. It receives amateur high altitude balloon imagery over USB RTL-SDR, runs as a progressive web app that works offline, and even receives on a phone (Chrome only via WebUSB). Demo shows live image frames, required fiddling with web audio filters, and a sub‑2‑minute build pipeline for deployment.
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chapters (20)
- 0:00Introduction
- 1:29Why mix C JavaScript and Python for decoding
- 2:54Amateur ballooning basics
- 5:00Horus binary telemetry
- 6:48Hardware setups
- 8:11Old Linux approach challenges
- 9:15Demo: web receiver
- 11:25Cross-platform goals
- 12:50Python-C interfacing with CFFI
- 15:40Wrapping C for Python
- 16:03Python in browser with Pyodide
- 17:48C libs in Python browser
- 18:53Replacing JS with Python
- 19:54Lightweight telemetry app
- 21:19Progressive web apps and offline functionality
- 22:45Web audio modem issues
- 23:50Web USB limits
- 24:35ARG balloon test
- 25:42Summary and future
- 26:27Question and answer session
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