🎵 Rewind.png

Digital cassette tapes disguised as PNG images

Rewind.png is an experimental media format that embeds lossless audio (FLAC/MP3/OGG/WAV) inside PNG images without corrupting the visual data. Think of it as a modern cassette tape; The PNG is the box art, and the embedded audio is the music inside.

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🎬 Demo

📼 Click to view the demo cassette (27.5 MB)

Try it: rewind tui demo/Cassette.png

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🎯 Why?

The ritual of physical media is dead. Music streaming is convenient, but it's also ephemeral—tracks disappear, playlists break, and there's no object to treasure. Rewind.png brings back:

• Tangible ownership: One file = one album + its cover art
• Intentional curation: Like burning a mixtape, each cassette is deliberate
• Fragility by design: Re-compress the image? The audio breaks. This forces careful handling, just like vinyl records.

Use cases:

• Gift custom mixtapes with personalized cover art
• Archive music collections with embedded album art
• Share music in a nostalgic, tactile format

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🛠️ How It Works

Polyglot File Structure

PNG Header Image Data (IDHR, IDAT Chunks) IEND Chunk
Table of Contents (TOC) - Track count - Track names & sizes
Audio Track 1 (FLAC/MP3/OGG/WAV) Audio Track 2 ...
CRC32 Checksum (Integrity Seal)

To image viewers: It's just a normal PNG.
To Rewind: It's a playable cassette with embedded audio.

Security Model

• Whitelist-only formats: Only FLAC, MP3, OGG, and WAV are allowed
• CRC32 integrity check: If the file is modified (e.g., re-encoded by social media), playback is blocked with: "This cassette has been damaged."
• Non-destructive embedding: The PNG image remains fully viewable

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📦 Installation

Prerequisites

• Rust 1.70+ (Install Rust)
• Audio files (FLAC/MP3/OGG/WAV)
• PNG image (for cassette cover art)

Build from Source

git clone https://github.com/Hyphonical/Rewind.png.git
cd Rewind.png
cargo build --release

Binary will be in target/release/rewind

System Requirements

• OS: Windows 10+, macOS 10.15+, or Linux (any modern distro)
• Terminal: Unicode support recommended for TUI (Windows Terminal, iTerm2, etc.)
• Audio: Working audio output device

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🚀 Usage

1. Create a Cassette (Record)

Inject audio files into a PNG image:

rewind record cover.png track1.flac track2.flac track3.flac -o mixtape.png

Output: mixtape.png (viewable as image, playable as audio)

2. Inspect a Cassette

View embedded tracks and verify integrity:

rewind inspect mixtape.png

Example output:

[00:00:00] ✔  Checksum matches. The file is intact.
[00:00:00] 𝒊  TOC: 6 audio file(s)
[00:00:00] 𝒊    [1] Track_1.flac (10000000 bytes) | 🎵 Artist 1 - Track 1 [1:23]
[00:00:00] 𝒊    [2] Track_2.flac (10000000 bytes) | 🎵 Artist 2 - Track 2 [1:23]
...

3. Play a Cassette

Play a random track (for testing):

rewind play mixtape.png

Output:

[00:00:00] ✔  ▶ Now Playing: Artist 1 - Track 1 [1:23]
[00:00:00] 𝒊  Press Ctrl+C to stop.

4. Interactive TUI Player (NEW in v0.5!)

Open the full-featured skeuomorphic cassette player:

rewind tui mixtape.png

Features:

• 🎨 Vintage cassette design with animated progress bar and spinning reels
• 🖱️ Mouse support - click buttons directly or select tracks
• 🔊 Volume control with visual slider (0-100%)
• 📜 Dynamic playlist that auto-sizes based on track count
• ⏯️ Full playback controls with visual feedback

Keyboard Controls:

Key	Action
↑/↓ or j/k	Navigate tracks
Enter	Play selected track
Space	Pause/Resume
←/→ or p/n	Previous/Next track
+/-	Volume up/down
S	Stop playback
Q or Esc	Quit

Mouse Controls:

• Click on any button (⏮ ▶ ⏸ ■ ⏭) to control playback
• Click on a track in the playlist to play it
• Click volume buttons to adjust audio level

Note: Your terminal must support Unicode box-drawing characters and mouse input for the best experience.

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🗺️ Roadmap

✅ Version 0.1 - Foundation (Completed)

• Core polyglot PNG/audio embedding
• Record audio tracks into PNG images
• Inspect cassette metadata & verify integrity
• Basic CLI playback

✅ Version 0.2 - CLI Refinement (Completed)

• Structured CLI with clap
  • rewind record <image> <audio...> -o <output>
  • rewind inspect <cassette>
  • rewind play <cassette> [--track N]
• Sequential playback (auto-advance tracks)
• Improved error handling and user feedback

✅ Version 0.3 - Basic TUI (Completed)

• Terminal UI with ratatui
• Interactive track selection
• Progress bar + metadata display
• Keyboard navigation

✅ Version 0.4 - Enhanced Playback (Completed)

• Improved audio handling with rodio
• Track metadata extraction (artist, title, duration)
• CRC32 integrity verification
• Pause/resume functionality

✅ Version 0.5 - Skeuomorphic TUI (Current)

• Complete UI redesign with vintage cassette aesthetics
• Mouse support (clickable buttons)
• Volume control with visual slider
• Dynamic playlist sizing
• Auto-play next track

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🚧 Version 0.6 - Polish & Distribution (Planned)

• Pre-built binaries for Windows, macOS, Linux
• Installer/package manager support
• Configuration file support (default volume, theme)
• Error recovery (handle corrupted tracks gracefully)

🎯 Version 1.0 - Desktop GUI (Future)

• Native desktop app with Tauri
• Drag-and-drop cassette loading
• Visual cover art display
• Cassette library (recently played)

🌟 Version 2.0+ - Advanced Features (Dreams)

• Web-based player (WASM)
• Multi-cassette mixtapes

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📜 License & Attribution

Code

This project is licensed under the MIT License. See LICENSE for details.

Demo Content

Demo Cassette Image (demo/Cassette.png):

• Cover art © 2025 Hyphonical. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0).
• You may: Share and redistribute the image with proper attribution
• You may not: Modify, remix, or create derivative works, or use it for commercial purposes.
• The Sony® trademark shown on the demo cassette is used for aesthetic purposes only. Sony is a registered trademark of Sony Corporation. This project is not affiliated with, endorsed by, or sponsored by Sony Corporation.

Demo Audio Tracks:
All tracks by Kevin MacLeod (incompetech.com):

• "Aquarium"
• "Sugar Plum Breakdown"
• "Hall of the Mountain King"

Licensed under Creative Commons: By Attribution 4.0 License

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📝 Notes

A great part of this project was created using various AI models, including Claude Sonnet & Opus, Gemini 3 Pro & Flash, and Grok Code Fast 1. Without these tools I would not have been able to create Rewind.png in this timeframe.

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Made with 💖