Unrolling a sheet into a linear sequence

[infojunkie]

I am wondering if there are published, well-known algorithms for "unrolling" a sheet music. By this I mean converting it to a linear sequence of musical events, without repetitions or loops - e.g. a MIDI stream.

I had to implement such an algorithm in my MusicXML to MIDI accompaniment generator project. To help validate it, I added a fairly involved test sheet and tested my output against MuseScore's. But having a published reference would be even better in terms of validation and comprehensiveness.

[mdgood]

I don't know of any such publication offhand. Since MuseScore code is open source, it seems it could be possible to write up their algorithm somewhere, with appropriate credit.

[benspratling4]

@infojunkie Did you end up finding one? I've spent the last 6 months banging my head against the wall trying to figure out how to figure out who sings what when, and right now my algorithm needs 9 passes over the song (and 15 before I'm done), and needs to do statistical analyses and I still need to build a wavelet analysis over lyric name / numbers to finish it off. My product will live or die on my getting this perfectly correct without a musician in the loop, to minimize the cost to publishers.

[infojunkie]

Yes, I made an XSL script that unrolls the MusicXML repeats and jumps into another format that I use for MIDI generation. The relevant logic is in the template that processes measures. It currently needs a single pass with lots of look-ahead and look-behind, and is probably very buggy 😄

[infojunkie]

Here's an XSL script that unrolls a MusicXML file to another MusicXML file that contains no jumps or repeats. I would love if someone else could test it.