I am not knowledgeable about midi, but when recording live play noone manage to play exact notedivisions/ticks within the chosen ppq and bpm, that is for transcribed sheetnotes ,if you write music?
And it would not sound musical if one did.
I guess you just round the timing value, number of ticks between note on->note off to the nearest full note partitioned value?

sorry Jonas, but that dump of a midi file was not obtained with a live recording, it was written with musescore, so I expected a very precise result. However, if from a midi file I read 1823 ticks instead of 1920 ticks, with ppqn = 480, it becomes difficult to establish that it is a 4/4 note.

Thanks anyway for the information.

Jonas is quite right.
Most/many sequencing programs do not enter a fuil note but usually about 95% of the full value.
You'll find that a quarter note is about 456 ticks, a half note about 912.
Some sequencers allow you to set the percentage duration.

I suspect that Musescore will change the duration to 100% if you mark the music as being played Legato.

thanks JohnG, I think it's as you say. Perhaps, software such as musescore, avoid inserting very precise ticks so that the less mechanical execution possible, more human.
Every day, a new one is discovered.

sorry Jonas, but that dump of a midi file was not obtained with a live recording, it was written with musescore, so I expected a very precise result. However, if from a midi file I read 1823 ticks instead of 1920 ticks, with ppqn = 480, it becomes difficult to establish that it is a 4/4 note.

Thanks anyway for the information.

I think you just calculate the tick amounts for the full note given PPQ and BPM and calculate partial note ticks as fractions, and then you compare which number of ticks closest to the "recorded" value. So for PPQ 480 and BPM 120 it becomes how close your value is to the below that decide what note value it have.
1920=1920/1, 960=1920/2, 480=1920/4, 240=1920/8, 120=1920/16,60=1920/32, 30=1920/64
At least that is the way i should do it.

But if the ticks just between.like 360 ticks... Well i know to little about sheet music to know howto handle that. I have a feeling though when in doubt shorten the note.

I will be a little heretic here at midi association another way ot think of it is simply use BPM, and use highest possible "realtime" recording values stored. At playup you will have a maximum polling speed depending on hardware. Changing BPM is a fractional change of your "recording".

BPM is of course just the metronome speed "and also the playup speed" changing between two BPM is a fractional timechange.

PPQ is really not necessary unless "your playup use ticks" i do not think i will rather maximum pollling speed, so there is still ticks of sort but they are not connected to "note length".
I guess you could say the polling speed of the realtime clock is the resolution of the recording, but it is not variable.
I would say it is probably more analog way to do things, "less quantisation?"

Ok enough of heretic rants for the day.

thanks Jonas.

To solve I simply do:

[code type=markup]
if (tick >= 1440 && tick <= 1920)
it's a 4/4 note
if (tick >= 960 && tick <= 1440)
it's a 2/4 note
[/code]

and so on

Yeah that is the way i would do it.

You probably want to leave room for 1/4 notes that last just a little longer than 1920 clicks.

I think you mean 480 clicks Mike 480=1920/4 (parts of full note) ?

Also, be prepared to find notes having values greater than their notated length, e.g. 481 or 961, etc.

When using various synths or VST sample players, in order to get musical phrases to sound correct, notes within a phrase are overlapped beyond the start of the next note, in order to cut out the attack portion of succeeding notes. Within such phrased sequences one will often find the MIDI controller CC#68 "on" (>64) before or during the first note of the phrase and off again during the last note. (Some VSTs use CC#64 for the same task.)

triggering of note-off event is not the exact end of the note. it also has to go through the release phase. if it goes note-off at the end of the 1/4 note, it will spill over to the next one.

the interval amount you described is consistent with typical muscore generated midi files.

I find correct what you say Yisheng. I wrote a midi-> wav converter calculating the buffer size for each note using the delta time as the buffer position; but at the end you always have to add a certain amount (0.5 seconds of sound) otherwise the release of the note is cut off.