Umulsai: A Plain-Text Format and In-Browser Engraving System for Jeongganbo, Korean Mensural Notation

2026-07-27

AI Summary

This study addresses the incompatibility of Korean traditional Jeongganbo notation with Western music engraving systems, stemming from its unique grid-based layout, right-to-left writing direction, and time-value encoding through character position and spatial proportion. To resolve this, the work proposes the first plain-text encoding scheme that maintains a one-to-one correspondence with Jeongganbo’s spatial structure and implements a dependency-free front-end rendering engine. This engine supports semantic modeling, automated layout rules, glyph rendering, and fine-grained spacing control, enabling high-quality display, printing, and audio playback directly in web browsers. Validation against authoritative scores confirms compliance with professional publishing standards, while the design establishes a foundation for future interoperability with MusicXML/MEI and optical music recognition systems.

Abstract

Jeongganbo is a grid-based mensural notation created in fifteenth-century Korea and still in standard use for Korean traditional music. Its structure -- a vertical column of square beat-cells read right to left, in which the position and share of a syllable inside a cell encode its duration -- is incompatible with engraving systems built for Western staff notation, and no practical digital tool for producing it has been in sustained distribution. This report describes the technical design of Umulsai, a jeongganbo editor that runs entirely in a web browser as a static, serverless application. Its core is (i) a human-writable plain-text format whose spatial arrangement corresponds one-to-one with the notational grid, so that duration is expressed by position and share in the text exactly as on the page; (ii) an engraving engine that formalizes the typesetting conventions of published scores -- right-to-left column flow, daegang section lines, octave-variant Sinographs, ornament attachment and micro-spacing -- as automatic rules; and (iii) a dependency-free implementation in which documents remain plain data, enabling print-quality output, playback, and interchange with recently proposed machine-oriented encodings of jeongganbo. We specify the format and its rhythmic semantics, describe the engraving model and its typographic edge cases, and discuss limitations and planned interoperability with MusicXML/MEI and optical music recognition pipelines. The implementation was produced through an AI-assisted workflow led by a domain expert and verified behaviorally against published reference scores; this workflow and its verification regime are disclosed in the report.

Problem

• Jeongganbo
• Korean mensural notation
• digital music notation
• engraving system
• plain-text format

Innovation

• Jeongganbo
• plain-text notation
• in-browser engraving
• mensural notation
• static web application