maidata-parser

A fast, strict simai chart parser that converts maidata notation to .ma2 format.

Download the latest binary from Releases.

---

Overview

maidata-parser takes a maidata.txt with metadata scheme, or a plain-text simai chart (the inote content inside a maidata.txt), and outputs a fully-formed .ma2 file ready for use, along with a console summary of note counts, timing metadata, and chart properties.

The parser faithfully implements the simai specification including BPM change compensation for holds and slides, pseudo-each (`) timing offsets, equivalent-BPM slide scaling, preview marker (###) extraction, and playability validation.

---

Download

Pre-built binaries are published on the Releases page.

---

Usage

maidata_parser -i <input> [options]

The input file can be a full maidata.txt containing &inote_ and &answer_ tags, or a raw text file containing only the body of an inote field. If a full maidata.txt is provided, the parser will automatically extract the chart corresponding to the specified difficulty ID.

Example

# Parse and write to output.ma2 (default)
./maidata_parser -i chart.txt

# Specify output path and difficulty ID
./maidata_parser -i chart.txt -o master.ma2 -d 5

# Quiet mode: print stats only, skip ma2 body to stdout
./maidata_parser -i chart.txt -q

# Parse a full maidata.txt directly for Master difficulty default ID 5
./maidata_parser -i maidata.txt

# Parse a full maidata.txt for Re:Master difficulty
./maidata_parser -i maidata.txt -o remaster.ma2 -d 6

Options

Flag	Default	Description
-i, --input	(required)	Path to the input maidata.txt or raw simai chart text file
-o, --output	output.ma2	Path for the output .ma2 file
-d, --difficulty	5	Difficulty slot ID (1 Easy · 2 Basic · 3 Adv · 4 Exp · 5 Master · 6 Re:Master)
-a, --answer-count	4	Answer sound count
-q, --quiet	off	Suppress .ma2 body output to stdout; print stats only

Difficulty and touch size — IDs 2 and 3 (Basic / Advanced) emit large-size touch notes; all other IDs use normal ones.

---

Console Output

On success, the parser prints a summary:

Resolution:     ...
Note count:     ...
Preview window: (..., ...)
is_DX:          ...

Time elapsed:               ... ms
Time consumption per note:  ... μs

Output written to: output.ma2

Field	Meaning
Resolution	Computed tick resolution (384–1920)
Note count	Total notes in the exported chart
Preview window	(start_ms, end_ms) from ### markers, or auto-derived 20 s window
is_DX	True if the chart uses any DX-exclusive note types or connected slides

---

Validation

The parser enforces playability constraints and will exit with an error if they are violated:

• Sensor conflicts — two notes occupying the same judgment region while one is still active (e.g. a tap landing inside an ongoing hold on the same button)
• Sensor overcommit — more than two simultaneous inputs required (touch, touch hold and slide are counted as one hand collectively)
• Slide geometry — invalid start/end combinations for straight, curve, V-shape, and opposite-side patterns

Error messages include the measure position and the raw simai fragment that triggered the conflict for easy tracing.

---

Notes

• This repository currently distributes compiled binaries only.
• The binary is self-contained and has no runtime dependencies.