FFmpeg is a collection of libraries and command-line tools for processing, converting, and streaming audio, video, subtitles, and metadata.

- Libraries cover codecs, formats, filters, devices, resampling, and scaling
- Tools include ffmpeg, ffplay, and ffprobe

Explore it here:
https://www.opensourceprojects.dev/post/ffmpeg

Ever Gauzy is an open-source business management platform that bundles ERP, CRM, HRM, and employee time tracking into a single codebase.

- Headless APIs with multi-currency and multi-lingual support
- Time tracking, activity monitoring, and timesheets built in
- Includes ATS, project management, invoicing, and inventory
- Desktop timer UI with standard and expanded modes

Your phone needs WiFi to send a file to another phone.

Or Bluetooth. Or AirDrop, which only works between Apple devices. Or Nearby Share, which only works between Android devices. Or a cable. Or a cloud service that uploads your file to a server in Virginia before sending it to a phone 3 feet away.

Every method needs infrastructure.

A developer who goes by Alstroph built a file transfer that needs nothing.

One phone flashes QR codes on its screen. The other phone points its camera at the screen and reads them. The file reconstructs on the receiving phone.

No WiFi. No Bluetooth. No internet. No app. No pairing. No account. No permissions beyond camera access.

Just light.

It is called Decimen Optical Transfer. Trending on GitHub. Tom's Hardware covered it yesterday.

Here is the clever part.

The sender never sends the same frame twice. Every frame is a random mix of pieces of the file. The receiver just needs to catch enough frames from any point in the stream and it can mathematically reconstruct the whole file. Missed a frame? Does not matter. Blurry frame? Does not matter. Out of order? Does not matter.

This is called a fountain code. Same math used in satellite communication.

Roughly 129 KB/s in the demo. Up to 186 KB/s propped steady. A 2 MB image in about 15 seconds.

When this matters:

Two phones on different networks. Two phones with no cell signal. Two phones in airplane mode. A secure environment where no wireless is allowed but a screen and camera exist. A country where the internet is shut down but screens still glow.

One honest note. This is a proof of concept, built overnight with Claude Code. Prior art goes back to divan's txqr in 2018. What makes this version notable is fountain codes running in a browser with zero install, on any phone with a camera.

2,602 stars in 2 days. 309 forks. MIT license.

Just a screen. A camera. And light.

100% Open Source.

(Link in the comments)