I Tested a File Transfer Tool With No Network At All (decimen)

Decimen is an open-source tool that transfers files between devices using nothing but a screen flashing QR codes and a camera reading them back — no WiFi, no Bluetooth, no network stack involved at all. In this video we break down how it actually works under the hood, from the fountain coding that makes it tolerant of missed frames to the exact reasons a laptop-to-phone transfer capped out at 3 KB/s instead of the claimed 128 KB/s. We test it in two real scenarios and dig into the source code to find out exactly why the numbers were so different. 🔗 Relevant Links Decimen App: https://decimen.app/ Decimen Github Repo: https://github.com/bashalarmistalt/de... ❤️ More about us Radically better observability stack: https://betterstack.com/ Written tutorials: https://betterstack.com/community/ Example projects: https://github.com/BetterStackHQ 📱 Socials Twitter:   / betterstackhq   Instagram:   / betterstackhq   TikTok:   / betterstack   LinkedIn:   / betterstack   📌 Chapters: 0:00 Intro 0:19 What Is Decimen 1:24 How Optical Transfer Works 1:43 Fountain Coding Explained 2:24 The Throughput Ceiling 3:03 QR Code Density Tradeoff 4:04 Demo 1: Laptop to Phone 4:25 Why It's So Slow (3 Reasons) 6:45 Demo 2: Phone to Phone 7:15 Capture FPS vs Decode FPS 7:43 Fixing Laptop-to-Phone Transfers 8:27 Applications & Wrap-up