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Quicktime Pitch bends

🔗Robert Walker <robertwalker@ntlworld.com>

11/29/2002 3:54:34 PM

HI there,

Sorry, now that I actually use the pitch bends I've been coding,
I find that QT is actually doing 512 pitch bend units to a semitone
here. That's the default pitch bend range.

They are indeed two byte integers, but the first _9_ bytes are
used for a semitone, not the first 8 as I was expecting,
and the remaining 6 bytes are used for the number
of semitones to give a range of +- 64 semitones.

If I do the pitch bend test using midi notes 58
with a pitch bend of 1024 and 62 with a pitch bend
of -1024 they both sound middle c so 1024 = one tone
so 512 = semitone...

I've added quick time support to the PlayMidiLib
(as an extra dll you can include with your program to
play notes via QT) but not yet uploaded it - a bit
later tonight prob. but some more testing and things
to do first

Robert

🔗Robert Walker <robertwalker@ntlworld.com>

11/29/2002 3:57:05 PM

Of course, bytes there should read bits - the first _9_ bits
etc...

Sorry,

Robert