Gilberto: ... > Also keep in mind that tick resolution is given in pulses per quarter note > (PPQ), not seconds. This means that a slow piece will have a lower > resolution /in true time/, i.e. ticks per second.
I don't think resolution /in true time/ matters, since each tick is "exact" in some sense. What matters is the smallest subdivision of a quarter note used (unless you use the smpte time format). > Finally note that the > reference is a quarter note, so if you have 384 PPQ, you then have 192 ticks > per eighth note, 96 per sixteenth note, 48 per thirty-second-notes. Given > that contemporary music can very much look like the image below, I think > there is a strong case for higher PPQ in order to have decent > representations of tuplets of very short note values: > > <http://lilypond.1069038.n5.nabble.com/file/t4165/maxresdefault.jpg> (My wild guess is that music would need a tick value of 64*9*5*7.) The technical limitation of midi file format is that the tick is a 15bit quantity, i.e. the maximum value is 2^15-1 = 32767. (Instead of "ticks" you could use a time code based time, guess that that is more for film making, don't know much about that.) So you can't get 128*9*5*7 = 40320, but 64*9*5*7 = 20160 is possible, and if you really need 128*9*5*7*11 or whatever, then you either need to choose a format other than midi, accept (smallish) time errors or you have to scale the notes, say make a quarter a whole note or longa (that would gain you a factor of 4 or 16). All note times in the file is delta times, and they are of variable length; the largest number allowed is 0x0FFFFFFF = 268435455, so if your tick is 2^15 (finest subdivision), the longest time is slightly less than 8192 quarter notes, which should be sufficient for most (all?) music. In effect, there is no need to choose a small tick value unless you want smaller midi files (a consern which should be irrelevant today) or perhaps due to some misbehaving midi equipment. Regards, /Karl Hammar ----------------------------------------------------------------------- Aspö Data Lilla Aspö 148 S-742 94 Östhammar Sweden +46 173 140 57 _______________________________________________ lilypond-user mailing list lilypond-user@gnu.org https://lists.gnu.org/mailman/listinfo/lilypond-user
