Is it possible to exterminate notes and rests?

• Sep 16, 2020 - 21:35

I know, this must sound weird, but it's still a serious question. ;-)

From time to time I work on scores that were converted from PDF to MuseScore. In the converted .mscz file I sometimes see measures with more notes and rests than the time of the measure allows. As an example, a "Bass clef" halfway the original PDF is sometimes recognized as a "Whole note" and added as another note with the other notes into the measure in the .mscz file. Yes, then it gets crowded there. (Excuse me, would you please take your elbow out of my eye? :-) )

I could correct this in an easy way if I can "exterminate" the notes or the rests that are too much. In the example that I gave I would completely remove the "Whole note" that was originally the "Bass clef" and the remaining notes and rests would then add up to the correct time of the measure.

Is this possible?

If not I'd like to toss in a feature request.

Thanks to everybody answering this question !


Comments

The problem with such a feature is that knowing what the original score looked like is required. Why? Because (almost) everywhere there is a spurious rest there is a note that is too long by that amount. Sometimes the note is on the same beat, sometimes not. That can only be determined by looking at the PDF. The PDF is imported using audiveris which is developed independent of MuseScore and it what actually needs to be fixed. Their site is http://audiveris.org/

In reply to by mike320

That's pretty much how I do it now.

I have the original PDF and the converted .mscz on the screen at the same time. Then I compare the two and I notice that, by example, a whole note somewhere in the .mscz file was originally a bass clef in the original PDF. I'd like to manually take out that whole note myself.

Right now I insert a new measure, copy over all the correct notes into the new measure, and then remove the "old" measure. That however, is more work, especially if it needs to be done repeatedly.

I'll try to find an example.

I agree that it's better if this is corrected at the source, e.g. with Audiveris, but I don't know how doable that is for them. I remember the first OCR applications with their "children's diseases". ;-)

In reply to by barencor

The OMR (Optical Music Recognition) program needs to be improved and MuseScore does not do OMR natively at all so it can't compare the music to the PDF. What you are asking for is impossible unless MuseScore ventures into native OMR which I don't think will happen any time soon.

In reply to by mike320

Here's an example of the original PDF. The purple arrow shows the Bass Clef that I mentioned:
PDFwithBassClef.png

Here's the same part when converted. The purple arrow now points at the note that I want to remove. (I just want to remove it myself) :
MsczWithWholeNote.png

I am not suggesting or asking that MuseScore compares the converted music to the PDF. I am asking if there's a way that I can remove that note myself. If I delete it now, it's replaced with a rest of the same duration and the measure is still corrupt.

Attachment Size
PDFwithBassClef.png 18.67 KB
MsczWithWholeNote.png 23.14 KB

In reply to by mike320

The measure that I point to (i.e. measure 4) has a "half note" plus two "eight notes" plus a "quart note" in the lower bar. That's a total of one. Where's the missing beat?

Correct, Audiveris doesn't handle it correctly. But I still need to do something. For the moment the only way to get it straight, is to correct it myself in MuseScore and that's what I have been doing.

The fastest way is to "take out" the "note" that's too much..

In reply to by barencor

Oops, my eyes played a trick on me. It's still not MuseScore's fault and there isn't much MuseScore can do to help the situation because things are added in strange places by Audiveris and MuseScore has no idea what should be in the measure and what shouldn't

In reply to by frfancha

I had tried that. It replaces the "whole note" with a rest (of the same duration).

What I get is a measure with a "half note" plus two "eight notes" plus a "quart note" plus a "whole rest", all in one measure. That's a duration of two, while each measure should have a duration of one.

Not easily. Think of the measure as a container. The music scanning software has counted the notes wrong and made a bigger container to fit them in. Deleting notes still leaves the container the same size and it must contain something so it contains rests.

Easier to insert a new measure (of normal length) and copy the good notes (and rests) over to it and then delete the bad measure.

In reply to by underquark

Actually, this would be an easy change. You are right that the measure (or container) size would also have to be changed, but that means changing a number in a record or a field that represents the measure size and that's easy. In SQL terms that would be something like this :

update [table name]
set measure-size = 1
where measure-id = 4

(Note, "4" is the measure-number from the example)

But if the people behind MuseScore don't want to do this, that's fine with me. I understand that sometimes there can be other priorities.

PS:
- Inserting a new measure and copying the correct notes and rests over and deleting the "bad" measure is what I did so far, but it's a tedious process. Thank you for the hint anyway.
- I do think that MuseScore becomes a much more valuable product, for many people, if users can correct converted scores easier. ;-)

In reply to by barencor

That's easy for this measure but in general these extra beats can be added anywhere in a measure and eliminating a spurious 8th rest on beat 2 might delete a legitimate 8th note but it may shorten a note that needs to be shortened. The only way to know is to look at the PDF.

In reply to by mike320

That's easy too.

If I "eliminate" a note or rest, then anything following that note or rest would move forward.

Here's an example of another "corrupt" measure :
A-CorruptMeasure.png

I would like to select the note or rest that shouldn't be there:
B-SelectCorruptRest.png

Then I would like to push ctrl-del (or another key combination) and the "corrupt" rest would be eliminated. The notes behind it would move forward and my measure is now correct:
C-Removed.png

This also means that eliminating an 8th rest never deletes another, legitimate note. If there's a legitimate note after the "corrupt" 8th rest, then the legitimate note would move forward, to the position where the "corrupt" rest used to be.

It compares to the way that I remove an entire measure right now. When removing an entire measure, the measures behind it now also move forward.

With 90% of the the corrupt measures that I saw, there was something too much in the measure. The process would be roughly the same for all of them. In maybe another 8%, tuplets weren't recognized as such. In those measures i saw three regular notes, where there should have been one tuplet with three notes. Then there was one measure that contained the notes of two measures combined. In another case the 3/4 sign at the start wasn't recognized. That gives funny results too. ;-)

Mmm ... maybe I should have started this thread with this information and this example?

Let me know if you see any other obstacles. I'll be happy to resolve those too.

Frfancha, thank you for your last comment. I'll check later. I hope you are right.

BTW, it's fine with me if this suggestion is declined. However, I think that this suggestion requires low effort to implement, while it has high value for those converting PDF's to MuseScore.

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