Obsidian Chord Transposer

A minimalist, zero-friction chord transposer for Obsidian.

Chord Transposer automatically detects chord lines in your song lyrics and lets you transpose them instantly. No complex code blocks, no proprietary syntax, no lock-in. Just plain text. Works seamlessly across Desktop, Tablet, and Mobile.

✨ Why this plugin?

Most chord plugins require you to format your songs in specific code blocks (e.g., ```chords). This breaks the flow of writing and makes your notes look like code.

Chord Transposer is different:

• Plain Text First: It works on standard Markdown text. Copy-paste lyrics from the web, and it just works.
• Portable Data: When you transpose a song, the plugin updates the actual text in your file. If you open your file in another editor, the chords are still correct.
• Intuitive UI: Transpose controls appear automatically in the header, but only when chords are detected.

🚀 Features

• Automatic Detection: Uses a smart heuristic algorithm (RegEx + logical analysis) to identify lines containing chords versus lyrics.
• Live Syntax Highlighting: Instantly highlights recognized chords in your editor (CodeMirror 6 integration) without changing your theme.
• One-Click Transposition: Transpose Up/Down semitones directly from the view header.
• Smart Parsing: Handles complex chords (F#m7, D/F#) and ignores common English words that look like chords (e.g., "Face", "Bad").
• State Persistence: Remembers the transposition setting for each song by saving it in the file's Frontmatter (YAML).
• Octave Reset: Automatically resets the counter to 0 upon reaching +/- 12 semitones.

🛠️ Installation

Via BRAT (Recommended for Beta)

1. Install the BRAT plugin from the Community Plugins browser.
2. Open BRAT settings -> "Add Beta plugin".
3. Paste the repository URL

Manual Installation

1. Download main.js, manifest.json, and styles.css from the latest Release.
2. Create a folder obsidian-smart-chords in your vault at .obsidian/plugins/.
3. Move the files into that folder.
4. Reload Obsidian.

Obsidian Community

1. After it got approved, directly install from Obsidian Community Plugins

🎮 Usage

1. Open a note containing a song.
2. That's it. The plugin scans the text.
3. If chords are detected, a control widget appears in the top-right header:
   • [↓]: Transpose down.
   • [↑]: Transpose up.
   • [↺]: Reset to original key (0).
4. The current transposition value is saved in your file metadata:

---
transpose: 2
---

🧠 Logic & Recognition

The plugin uses a sophisticated "Strict Regex" approach to differentiate between music and text:

• Allowed: Standard chords (Am, G7, F#m), Slash chords (D/F#), and extensions (6/9, maj7, dim).
• Ignored: Common English words that resemble chords are automatically filtered out (e.g., "Aged", "Cafe", "Face", "Dad").
• Threshold: A line is considered a "Chord Line" if >40% of the tokens are recognized as valid musical chords.

💻 Development

This plugin was built using TypeScript and the Obsidian API.

1. Clone the repository.
2. Install dependencies: npm install
3. Build: npm run build

📄 License

MIT License. Feel free to fork, modify, and use it as you wish.