> That Opusmodus has adopted MusicXML as the de facto standard for displaying notated scores should be no surprise. This is inextricably bound up with the development of the distinctive Opusmodus Notation script (OMN). It gives the composer the means to design into the very composition of a score a host of musical details that have until now been impossible to bring together in a single line of script.
What are some other notable and open formats for notating scores? I'd like to know the what the popular formats are, do a survey and choose one for my own work.
ABC is the other major player in the space besides MusicXML and Lilypond.
The Mutopia project [1] is magnificent but largely abandoned in favor of MuseScore [2] which uses MusicXML. The amount of music available there is staggering but locked in to their backend.
Unfortunately automated translation is difficult because Lilypond is very oriented towards specifics on how the notation is rendered.
And, if you are interested in general archives of music, IMSLP [3] (Internet Music Score Library Project) has to be mentioned as well, but mostly contains scans of existing engraved music.
It's an open JSON format that's being hashed out by members of the music technology community. It's not production-ready yet, but I encourage you to get involved in the discussions! https://github.com/w3c/mnx/
(I lead creation of the format, as one of the co-chairs of the W3C Music Notation Community Group.)
MusicXML is pretty much the game in town as far as open formats go. Lilypond is an open TeX-like format, but it's really a domain-specific programming language for Lilypond itself.
https://opusmodus.com/forums/notation-viewer/