craigsapp
commented
4 years ago timebase is part of the standard Humdrum tools, and they in general do not allow rhythms to cross barlines. The parser in Humextras does not allow it either, but the parser in Humlib does. So re-implementing timebase in humlib is what you want. In addition, that would allow it to be added as a filter in VHV.
One temporary solution to the problem is to make every barline a global comment, since durations can pass through global comments in the Humdrum toolkit tools. Then remove the global comments afterwards. Also note that timebase eats grace notes, so you need to comment these out as well to preserve them when passing the data through timebase. In addition, you need to use the correct minimum time unit (calculated by the humextra minrhy tool) because an non-minimal timebase will each shorter duration events. In other words, if you timebase -t 16 a score, then all of the 32-note offbeats will be removed. So in its current form, the timebase tool is not a general solution for adding extra spaces to fill in for tremolos. A separate tremolo-expansion tool may be ideal; otherwise, a timebase feature that does not drop sub-timebase events nor graces notes, but allows note durations across barlines is what you want 😜
The partjoin script (part of humextra) preserves grace notes in this manner: http://extras.humdrum.org/scripts/perl/partjoin/partjoin
Before the data is sent to timebase, tokens with q are prefixed with !QqQ to make them local comments:
if ($line =~ /q/) {
my @fields = split(/\t/, $line);
for (my $j=0; $j<@fields; $j++) {
$fields[$j] = "!QqQ$fields[$j]";
}
$contents[$i] = join("\t", @fields);
}Perhaps a global comment would work as well (I was probably being careful about a non-gracenote from being commented, but in theory grace notes and regular notes should never occur on the same line.
The QqQ is a string that is used to mark the comment so that it can be unconverted from a local comment later. In partjoin I do it the hard way, but in general:
$line =~ s/\!QqQ//g;Should work to remove the embedded grace notes.
timebaseunfortunately does not work with rhytmic values crossing the barline:file.krntimebase -t 16 file.krnoutput:
Would it be possible to allow this kind of rhytms in
timebase?It would be also very helpful if
timebasewas built in Verovio Humdrum Viewer - that would help to deal with tremolo for instance.