OMR in musescore
I've forked MuseScore and worked on the revival of OMR for a while. Here are some current state of arts:
and the documentation:
I was using Poppler to import PDF and a graphical model to identify the system configuration (if we don't know in prior how many staves per system). There is still large room for improvement such as building a more sophisticated bar line detector. But the current work will provide an initial framework of lightweight OMR that can be directly used by MuseScore users. I've sent a PR for my updates in OMR part and hopefully it'll be merged very soon. Feel free to discuss if you're interested.