sky-studio-abc.js

Read and write Sky Studio score files (.txt and .skysheet.json) from Node.js. The API mirrors nbs.js: every section of the score is its own class exposing a paired static deserialize and serialize.

Install

npm install sky-studio-abc.js

Quick start

const SkyStudioABC = require("sky-studio-abc.js");

// 1. Parse a .txt file (the "<DontCopyThisLine>" format)
const sheet = SkyStudioABC.deserialize("<DontCopyThisLine> 320 0 16 Unknown_a Unknown_a\n. . . B3B5C2 .\n");

// 2. Parse a .skysheet.json file (single sheet or an array of sheets)
const sheets = SkyStudioABC.deserialize(fs.readFileSync("song.skysheet.json", "utf-8"));

// 3. Serialize back to either format
sheet.serializeABC();   // -> .txt string
sheet.serializeJSON();  // -> JSON string

// 4. Play through the sixteenth-note grid
for (const tick of SkyStudioABC.createPlayer(sheet)) {
  tick.tick;   // grid position
  tick.mask;   // bitmask of notes sounding
  tick.notes;  // ["B3", "B5", "C2"] and so on
}

deserialize sniffs the input automatically: JSON starts with { or [, the .txt format starts with <.

API

The default export is the SkyStudioABC document class. The section classes are also attached to it:

| Export | Description | | --- | --- | | SkyStudioABC | Top-level document — deserialize, serializeABC, serializeJSON, createPlayer | | SkyStudioABC.SkyStudioHeader | Song metadata (bpm, pitchLevel, bitsPerPage, authors, rhythm) | | SkyStudioABC.SkyStudioNote | One note with exact onset time (key, time, track) | | SkyStudioABC.SkyStudioTick | One grid cell (tick, mask, notes) | | SkyStudioABC.SkyStudioInstrument | A .skysheet.json instrument track | | SkyStudioABC.SkyStudioPlayerIterator | Walks every tick, yielding empty cells as mask: 0 | | SkyStudioABC.NOTES | The fifteen note names ("A1" … "C5") | | SkyStudioABC.NOTE_INDEX | Reverse lookup, note name → bit index |

Main methods

• SkyStudioABC.deserialize(input) — accept .txt string, JSON string, or parsed object/array.
• SkyStudioABC.deserializeABC(input) / deserializeJSON(input) — the two formats directly.
• SkyStudioABC.createPlayer(sheet) — returns an iterator over the grid.
• sheet.serialize() — alias of serializeABC().
• sheet.serializeABC() / sheet.serializeJSON(pretty?) — emit .txt / JSON.
• sheet.notesToTicks() / sheet.ticksToNotes() — convert between exact-time notes and the quantised grid.

Data model

• ticks — a dense sixteenth-note grid of bitmasks (one bit per note name).
• notes — exact-time notes (SkyStudioNote[]), used by the JSON format.
• header — metadata shared by both formats.

License

MIT