MIDI timing

[Clemens Ladisch]

Goran Mekić wrote:
> I have a simple MIDI file:
> https://github.com/mekanix/libmaolan/blob/feature/midi-example/data/example.mid
>
> Acording to http://www.ccarh.org/courses/253/handout/smf/

The official SMF specification can be downloaded from www.midi.org.

> there is the info of divisions per beat. For the example.mid I get that
> divisions are 19200

00000000: 4d 54 68 64 00 00 00 06 00 00 00 01 4b 00 4d 54  MThd........K.MT

Correct.

> so I assume if I have 100BPM song

This file does not contain any tempo events, so you have to assume 120 BPM.

> this would translate to 192000 divisions per second.

            19200 * 100 = 1920000

"Division" is the name of the field in the header, but not of the unit of
time specified by it.  This field specified _ticks_ per beat.

With 120 BPM, you actually have 2304000 ticks per second.

(And the tempo event would not specify BPM, but microseconds per beat.)


Regards,
Clemens