Re: When (in seconds) does each page begin?

[Matt Wallis]

On 28/05/2020 19:29, Valentin Villenave wrote:
> On 5/28/20, Matt Wallis <m7956@acumen-it.co.uk> wrote:
> > I would like to obtain timing information to tell me at how many seconds
> > into the score each page begins. I have had a go at this, and failed.
>
> If you’re trying to make videos out of LilyPond scores, here are some
> links for you:
> https://lists.gnu.org/archive/html/lilypond-user/2020-03/msg00275.html
> https://lists.gnu.org/archive/html/lilypond-user/2020-03/msg00276.html
> https://lists.gnu.org/archive/html/lilypond-user/2017-11/msg00098.html
> https://lists.gnu.org/archive/html/lilypond-user/2017-07/msg00234.html
> https://gitlab.com/sigmate/lilypond-html-live-score
>
> (That doesn’t answer your question, but others will certainly chime in :-)

Many thanks for the links. Some of them I have seen before, but I'm not 
keen on a solution that requires patching lilypond. The others, I will 
look into.

Yes- as you suspected, I want to make videos. My initial needs are very 
basic - just to display each page at the correct time. I currently get 
the timings from a simple script that plays the audio, and I press 
'enter' each time the page of the score changes, to record the timing. 
But I want to automate this. With that timing data alone, I can produce 
very basic videos that meet my (initial) requirements.

The output from event-listener is so close. I just need to get it to 
listen to the appropriate events ... if that is possible.

Maybe I'll want to colour notes too at some point :-) Perhaps those 
links will answer the next question: Can I dump out from lilypond the 
following information for each note:

note start time;
note duration;
co-ordinates of the centre of the note on the PNG created by lilypond

I think that's all the data needed from lilypond in order to create a 
quite nice video with note highlighting.

How difficult can that be? :-) Is it the case that this can't be 
triggered neatly from a note event, because when the note event is 
received, the engravers have not yet decided where on the score that 
note should be put?

Matt