Encoding Audio Inside PNG Images [video]
YouTube video review, not a shipped project with code or tooling.

Audio-based text modem solves Iran shutdown use case; genuinely novel constraint.
Activists, researchers, users in internet shutdowns, offline communication use cases
## Problem statement:
- during Iran internet shutdown, the government cut off phone lines and mobiles (no text or calls). Gradually they opened up landlines and then phones, but still texting/SMS was down with no real internet.
- There were still ways to connect through proxies, vpns, DNS tunnels, etc. However, people had no way to send each other VPN config files or proxy urls/passwords/etc (they needed to call and read them over the phone)
## Solution: - TLdr; A modem: a way to transfer text (e.g VPN config) over phone calls
Here's the github issue for community testings, Please try and let me know what you think: https://github.com/shayanb/Nedagram/issues/5
p.s. there is a CLI version too, would be cool to see what people would do with it: https://www.npmjs.com/package/nedagram
YouTube video review, not a shipped project with code or tooling.
This is practical, low-level tooling: the addon runs Opus encode/decode and all RTP I/O on native threads so the Node event loop stays out of the way — exactly what you need when streaming audio to AI models. It bundles helpful primitives (createRtpParameters / createSrtpParameters / createSDP, produceRtp/consumeRtp) but does require native deps (FFmpeg/libopus) and currently only documents macOS/Linux builds.
Free browser meter with FFT analysis, but calibration depends entirely on your microphone hardware.
Information theory says this can't work — no benchmarks or working hardware shown.
QR code file transfer with ECDH encryption when the internet isn't an option.
Full C audio engine running in-browser via Emscripten with a custom ASCII notation language.