video frame grabbing

• May 2, 2018 - 08:41

I have a situation where I am unable to use the youtube video export. Specifically I am working with a font of symbols not supported by google/musescore fonts. I am also trying to sync the score to a film running 24fps; it is a lot of work marking up each measure and scaling the score measure into the film measure; but this is not the problem of the forum topic.

Instead I am using quicktime screen recording and play the score in continuous view. It records at 60fps, and generally it works out when I put it into a video editor and sync it to film.

I am noticing one problem that I have been unable to work around or explain.

When I look at the score video frame by frame I am noticing the highlighted time bar does not smoothly move with time. Sometimes it lingers on a note, or it might jump a number of 16th notes, 95% of the time the film and the highlighted score notes match up.

The tempo is 200 bpm/quarter note, and most of the arrangement is in 16th or 32nd notes.
have a current computer, current OS, current musescore. The audio is fine, no distortion.

It seems to repeat at the same notes on different recordings. but I have not completely verified this.
I tried changing the tempo to 50bpm, same anomalies.
I tried creating an instrument that only plays the same 16th note over & over, no change.

Any ideas or suggestions?

Thanks, Matthew

Comments

• May 2, 2018 - 11:25

You wrote:
I am noticing the highlighted time bar does not smoothly move with time.

If you are talking about the cursor that moves along with the score playback, it is a visual cue not only for notes played, but also for counting beats.
For example, if you watch the cursor play a succession of 8th notes, it glides fairly uniformly across the score. A series of a dotted eighth and 16th note pairs will exhibit some 'jerkiness' when the 16th notes are sounded.
For whole notes, the cursor moves over the note, momentarily stopping on each of the succeeding 3 beats. (It almst looks as if it's playing 'invisible' quarter notes - but it's counting beats.) This is more noticeable at slow tempos, or if the measure with the whole note is stretched out across the page (e.g. in page view).

So...
For a smoother overall playback.motion, try the piano roll editor. (Right click on an empty part of the staff then choose Piano Roll Editor..)
Maybe you can record that and somehow add/paste your special symbols using a video editor.

Regards.

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• May 2, 2018 - 21:11

thanks for getting back.

The piano roll editor is not an option, need the score. I did try a few more experiments and got to a better place. I did two previous experiments in combo, and a couple others.

I created a crotales instrument, and hit a note every 32nd with the tempo at 200, previous I had done 16th notes. The audio failed with a lot of clipping. I slowed the tempo in half. The audio restored, and the cursor bar ran smoothly. I went back to 16th notes, with the tempo at 100. I still would see glitches, but far few. Not sure if this is a musescore issue or a quicktime frame grabbing issue. All it takes is some 'OS event' to delay processing; I see similar things with disks and background apps asserting their priority.

Is there a way to disable the cursor all together?

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