Audiveris / audiveris

Latest generation of Audiveris OMR engine
https://audiveris.github.io/audiveris
GNU Affero General Public License v3.0
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problem to transcribe a good quality score with compressed notation format #693

Closed Bacchushlg closed 1 year ago

Bacchushlg commented 1 year ago

The appended score is of rather good quality, but is uses a unusual compressed format. Is it possible to improve transcription by modifying certain parameters? What is especially unclear to me is that it does not recognize most of the beams.

So soll es bleiben.pdf

hbitteur commented 1 year ago

I just checked your input image.

Running the SCALE step gives a measured beam height of 6 pixels:

image

Looking at the image, we can see:

In other words, the contribution of these thick "lines" will outperform the contribution of beams into the scaling black histogram. Here is the histogram, via Sheet | Display scale plots:

image

Beam scale should be set to 9 instead of 6. For confirmation, you can manually measure the real height of any concrete beam:

image

You cannot change the input image, but you can tell Audiveris to use a specific beam height. This is done via Book | Set book parameters. Select the book tab, because the beam specification will apply equally well to all sheets of the book:

image

Specify the value 9 for beam height. Press Ok or Apply. You can also save the book, this will save the specification.

Then restart your transcription from scratch.

Happy transcription!

hbitteur commented 1 year ago

FYI, I'm working on broader specifications for 5.4. They will address:

Bacchushlg commented 1 year ago

It seems that the beam thickness algorithm has problems... In all sheets it results in thickness 6, although the other pages are full of beams. Setting the value to 9 does not allow to transcribe all sheets, unfortunately

hbitteur commented 1 year ago

In all sheets it results in thickness 6

Pay attention to set the beam specification at book level, so that all sheets can benefit of the spec.

I get an IndexOutOfBoundsException in BeamLinker class for sheets 3, 4 and 5. I had checked sheets 1 and 6 only. This is really bad luck! :-)

Apart from this problem, beams are correctly processed.

I'll try to push a bug fix tonight.

hbitteur commented 1 year ago

The IndexOutOfBoundsException cases have been fixed by commit eb837d6a5d23a0f91ccf8dc0c371dc9ec8aedf89 in development branch. Please pull and retry the whole book on your own.

Bacchushlg commented 1 year ago

Transcription now was performed without severe errors. Thank you!