offline - Added a quick reference on using simple stegonography to hide data inside images

overlay/etc/skel/Desktop/offline/crypto/steghide.md

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+---
+title: "Steghide: Steganography Quick Reference"
+date: 2026-03-22
+updated: 2026-03-22
+author: [The Tech Prepper]
+categories: [cryptography, reference]
+tags: [steghide, steganography]
+copyright: "(C) 2026 The Tech Prepper, LLC"
+---
+
+Steghide is a command-line tool used to embed and extract hidden data
+within image or audio files using steganography. This document provides
+an example using the JPEG image file format to hide and recover a 
+hidden file with a secret message.
+
+
+## Extract Hidden Data from A JPEG Image
+
+Run the following command and use the password `beprepared` when prompted
+to extract the secret file from the image named `steghide.jpg` in this
+directory.
+
+```
+steghide extract -sf steghide.jpg
+```
+
+Run `cat secret.txt` to view the contents of the hidden file.
+
+
+## Embed Data in JPEG File 
+
+Hide a file (i.e. secret.txt) inside a JPEG image. Replace IMAGE with
+your own JPEG image file.  This will create a file named `output.jpg` with
+the file `secret.txt` hidden inside.
+
+```
+steghide embed -cf IMAGE -ef secret.txt -sf output.jpg
+```
+
+
+## Best Practices
+
+- Use large, high-quality cover files
+- Do NOT compressing images after embedding
+- Use strong passphrases
+
+
+## Common Workflow
+
+1. Prepare a secret file
+2. Select a large enough cover image to store your hidden file
+3. Embed using steghide
+4. Post or share the output image in plain sight