LibreScore
webmscore
MuseScore's libmscore (the core library) in WebAssembly!
Features
- Parse
msczfile data - Get score metadata
- Export part score
- Generate music sheets in SVG/PNG/PDF format
- Generate MIDI
- Generate audio files in WAV, OGG, MP3, or FLAC format
- Synthesize raw audio frames, can be used in the Web Audio API
- Export as MusicXML compressed/uncompressed
- Generate position information of measures or segments on the generated sheets
- Run inside a Web Worker thread
Installation
The package is available on npm: https://www.npmjs.com/package/webmscore
npm i webmscoreUse webmscore
Load in browsers
<!-- using a CDN -->
<script src="https://cdn.jsdelivr.net/npm/webmscore/webmscore.js"></script>
<script>
WebMscore.ready.then(async () => {
const score = await WebMscore.load('mscz', msczdata)
})
</script>For latest browsers which support ES Modules
import WebMscore from 'https://cdn.jsdelivr.net/npm/webmscore/webmscore.mjs'Run in Node.js directly
Minimum version: v8.9.0 with ES Modules support
The --experimental-modules flag is required for Node.js versions under 14,
Also require "type": "module" in package.json
import WebMscore from 'webmscore'
WebMscore.ready.then(async () => {
const score = await WebMscore.load('mscz', msczdata)
})Use a JavaScript bundler
(TBD)
Load extra fonts
If your score sheet contains characters out of the range of the bundled FreeFont, those characters will be shown as tofu characters (□ or �) in SVG/PNG/PDF files. Loading extra fonts is required.
webmscore can load any font format supported by FreeType.
const score = await WebMscore.load('mscz', msczdata, [...arrOfFontData])CJK fonts are no longer bundled inside webmscore since v0.6.0
Load soundfont files
Loading a soudfont (sf2/sf3) file is required before generating/synthesizing audio.
await score.setSoundFont(soudfontData)Soudfonts can be found on musescore.org website.
Example: (FluidR3Mono_GM.sf3)
const soudfontData = new Uint8Array(
await (
await fetch('https://cdn.jsdelivr.net/gh/musescore/MuseScore@2.1/share/sound/FluidR3Mono_GM.sf3')
).arrayBuffer()
)Boost Mode
Sometimes you only want to process a bunch of score metadata, so drawing sheet images internally is a waste of time and system resource.
You can enable the Boost Mode by setting the doLayout parameter in WebMscore.load to false.
Example:
const score = await WebMscore.load('mscz', msczdata, [], false)
const metadata = await score.metadata()
score.destroy()webmscore's Boost Mode is about 3x faster than the batch converter feature (-j) of the musescore software, according to the benchmark result.
WebAssembly vs native C++ program!
Compiling
Install essential tools like
make,cmake,llvm, etc.Install
emscriptenv2.0.6 usingemsdkhttps://emscripten.org/docs/getting_started/downloads.htmlGet Qt5 for WebAssembly and apply patches
AQT_PREFIX=$PWD/build.qt5
Qt5_VER=5.15.2
Qt5_DIR=${AQT_PREFIX}/${Qt5_VER}/wasm_32
# if you change the install directory or Qt version, remember to also change the `PREFIX_PATH` variable in `web/Makefile` file
# Download Qt using aqtinstall (https://github.com/miurahr/aqtinstall)
pip install aqtinstall==2.1.*
aqt install-qt linux desktop ${Qt5_VER} wasm_32 --outputdir ${AQT_PREFIX} --archives qtbase
# # Compile the `offscreen` platform plugin
# aqt install-src linux desktop ${Qt5_VER} --outputdir ${AQT_PREFIX} --archives qtbase
# cd ${AQT_PREFIX}/${Qt5_VER}/Src/qtbase/src/plugins/platforms/offscreen
# ${Qt5_DIR}/bin/qmake offscreen.pro && make
# cd - && cp -r ${AQT_PREFIX}/${Qt5_VER}/Src/qtbase/plugins build/qt/
# Apply patches, which
# enable the prebuilt `offscreen` QPA platform plugin (https://doc.qt.io/qt-5/qpa.html), and
# exclude other Qt5Gui plugins
cp -r build/qt/* ${Qt5_DIR}
# Patch emcc.py to emit separate .mem files regardless of MEM_INIT_METHOD settings (MEM_INIT_METHOD won't work with wasm)
sed -i -r "s/(shared.Settings.MEM_INIT_IN_WASM = )True/\1False/" "$(which emcc).py"- Checkout submodules
git submodule init
git submodule update- Compile
webmscore
cd web-public
npm i
npm run buildBuild artifacts are in the web-public directory
Browser Support
All modern browsers which support WebAssembly and Async Functions
| Name | Minimum Version |
|---|---|
| Chrome | 57 |
| Firefox | 53, 52 (non-ESR) |
| Edge | 16 (Fall Creators Update) |
| Safari | 11 |
| IE | NO! |
| Other browsers | I don't know! |
Only tested on the latest version of Chrome and Firefox.
Examples
see files in the web-example directory
cd ./web-example
npm i
npm start # Node.js example
npm run start:browser # browser exampleDebugging
See How to look up function names in the .symbols file?
webmscore is part of the LibreScore project.