Split Encoding

Split Encoding

Split Encoding distributes your secret across multiple images. All images are required to reconstruct the message.

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How It Works

Your secret is divided into chunks, each encrypted and hidden in a separate image:

┌─────────────────────────────────────────────────────────────┐
│                    Your Secret Message                      │
├─────────────────────────────────────────────────────────────┤
│                           │                                 │
│              ┌────────────┼────────────┐                    │
│              ▼            ▼            ▼                    │
│         ┌────────┐   ┌────────┐   ┌────────┐                │
│         │ Part 1 │   │ Part 2 │   │ Part 3 │                │
│         │ Image  │   │ Image  │   │ Image  │                │
│         └────────┘   └────────┘   └────────┘                │
│                                                             │
│         All 3 required to reconstruct the message           │
└─────────────────────────────────────────────────────────────┘

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Use Cases

Distributed Trust

Split a master password across images stored in different locations:

• Image 1: Your phone
• Image 2: Cloud storage
• Image 3: USB drive at home

Team Access

Share access that requires multiple people:

• Each team member holds one image
• All must collaborate to decode

Dead Man's Switch

Information that should only be accessible if multiple conditions are met.

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How to Use Split Encoding

Encoding

1. Select the Split tab in Encode mode
2. Select multiple cover images (2 or more)
3. Enter your secret message or file
4. Enter a password
5. Click Encode
6. Save each encoded image

Decoding

1. Switch to Decode mode
2. Select the Split Decode tab
3. Load all the split images (in any order)
4. Enter the password
5. Click Decode

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Important Notes

⚠️ All Parts Required

If you lose any image, the data is gone forever. There's no recovery option.

Images Provided	Result
All images + correct password	✅ Message recovered
Missing 1 image	❌ Cannot decode
Wrong password	❌ Cannot decode

💡 Best Practices

1. Keep backups of all split images in separate locations
2. Number your images or use clear naming (part1.png, part2.png, etc.)
3. Test decoding immediately after encoding to verify
4. Document the split — record how many parts exist
5. Use the same password for all parts (required)

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Technical Details

Chunk Distribution

Data is split using a deterministic algorithm:

• Each chunk gets a sequence number (1, 2, 3...)
• Chunks are independently encrypted
• Each image stores one chunk + metadata

Metadata Stored

Each split image contains:

┌─────────────────────────────────┐
│  Split Metadata                 │
├─────────────────────────────────┤
│  Part Number:  2                │
│  Total Parts:  3                │
│  Chunk Hash:   SHA-256          │
│  Session ID:   Random UUID      │
└─────────────────────────────────┘

The Session ID ensures parts from different encoding sessions can't be mixed.

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Comparison: Standard vs Split

Feature	Standard	Split
Images needed	1	2+
Single point of failure	Yes	No
Storage requirement	Lower	Higher
Complexity	Simple	Moderate
Use case	Personal secrets	Distributed trust