Re: LilyPond and visually impaired accessibility

[address@hidden]

On Mar 24, 2011, at 10:46 AM, Reinhold Kainhofer wrote:

> Am Donnerstag, 24. März 2011, 15:07:54 schrieb Han-Wen Nienhuys:
>> I think it would be awesome to have MusicXML output, but I am not sure
>> about the technical constraints.  IIRC, MusicXML has a complicated way
>> of mixing layout and abstract music information, that would make it
>> difficult to produce fully fledged musicxml from LilyPond easily; 
> 
> Actually, MusicXML 1.0 was just about musical content, which is not too hard 
> to produce in lilypond. MusicXML 2.0 added lots of attributes for display, 
> exact item positioning, layout etc. MusicXML does not require applications to 
> export exact positioning and layout information, so for now exporting only 
> the 
> musical content is fine. Just look at most of the files in 
> input/regression/musicxml/ for examples. 
> 
> As a first step, it would suffice to only export the musical content (part-
> wise, i.e. at the Staff/PianoStaff level).
> The second step, exporting the exact positioning and layout information is 
> much harder, as that information is only available at the very end of 
> lilypond's processing, when you don't have easy access to the music events 
> any 
> more. I.e. you don't have the link between the grob (with its exact position) 
> and the musical event that caused it (which will be the XML element exported 
> to the MusicXML file).
> 
> Of course, there are several problems:
> -) All lyrics are always contained in a part (i.e. a staff). There is nothing 
> like the stand-alone Lyrics context in lilypond.
> -) The same goes for FiguredBass etc.
> -) All staves inside a PianoStaff should be exported as one part, while all 
> other staves are exported as separate parts.
> -) All Staves start at the very beginning and end at the very end in MusicXML 
> (of course, you can hide them for some portions of music).
> etc.
> 
> Cheers,
> Reinhold
> 
> 


I'd be comfortable just implementing something that parsed 1.0 standard stuff 
for Braille music.  IIRC, this music does not depend on layout info.  It also 
seems like a good place to stop & work out all the bugs, at which point one 
could add in layout information.

Cheers,
MS