https://jsokit.com/blog/tags/decoding/ Recent content in Decoding on JsonKit Blog Hugo en © 2025 JsonKit Fri, 24 Apr 2026 17:29:48 +0000 https://jsokit.com/blog/posts/qr-code-decoding-from-finder-patterns-to-data-extraction/ Fri, 24 Apr 2026 17:29:48 +0000 https://jsokit.com/blog/posts/qr-code-decoding-from-finder-patterns-to-data-extraction/ QR Code Decoding: From Finder Patterns to Data Extraction Building a mobile QR scanner got me curious about the underlying decoding algorithm. It’s way more sophisticated than I expected—here’s how it actually works. QR Code Anatomy: The Three Finder Patterns The most obvious feature of a QR code is the three square blocks in the corners. These are finder patterns, and they’re the key to fast positioning regardless of rotation or perspective distortion. https://jsokit.com/blog/posts/linux-uptime-command-understanding-system-load-and-uptime-monitoring/ Wed, 08 Apr 2026 15:27:39 +0000 https://jsokit.com/blog/posts/linux-uptime-command-understanding-system-load-and-uptime-monitoring/ Linux uptime Command: Understanding System Load and Uptime Monitoring When managing servers, quickly assessing system health is essential. The uptime command outputs just one line, but it contains critical information for judging system health. Let’s dive into the principles behind this seemingly simple command. Decoding uptime Output $ uptime 14:32:18 up 47 days, 3:21, 5 users, load average: 0.15, 0.10, 0.05 This single line contains four key metrics: Field Meaning Example Current Time System clock 14:32:18 Uptime Time since boot 47 days, 3:21 Users Active sessions 5 users Load Average 1/5/15 minutes 0. https://jsokit.com/blog/posts/building-a-jwt-debugger-in-the-browser-base64url-decoding-and-signature-verification/ Wed, 11 Mar 2026 17:55:24 +0000 https://jsokit.com/blog/posts/building-a-jwt-debugger-in-the-browser-base64url-decoding-and-signature-verification/ Building a JWT Debugger in the Browser: Base64URL Decoding and Signature Verification If you’re a backend developer, you’ve probably pasted a JWT into jwt.io more times than you can count. But have you ever thought about what happens behind the scenes when you hit that “decode” button? Let’s walk through building one from scratch. The Three-Part JWT Structure A JWT looks like this: eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9. eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIn0. SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c Three dot-separated segments: Header, Payload, Signature. https://jsokit.com/blog/posts/base64-encodingdecoding-from-btoa-to-full-unicode-support/ Sat, 24 Jan 2026 15:39:10 +0000 https://jsokit.com/blog/posts/base64-encodingdecoding-from-btoa-to-full-unicode-support/ Base64 Encoding/Decoding: From btoa to Full Unicode Support I recently worked on a project requiring safe text data transmission, and Base64 encoding was unavoidable. While I’ve used it countless times, implementing a reliable tool revealed some interesting details worth sharing. What is Base64? Simply put, Base64 is a method to represent binary data using 64 printable characters: Uppercase letters A-Z (26 characters) Lowercase letters a-z (26 characters) Digits 0-9 (10 characters) + and / (2 characters) Plus = for padding at the end.