A response to Jody's comment that MIDI files made directly by software
from a scanned sheet of music sound mechanical.

I wrote and still use a graphics program that lets me draw sheet music
on the screen with a mouse, and then play it out via MIDI.  This should
sound just as "mechanical" as a direct sheet music conversion, or any
non-hand-played piano roll, or any barrel organ.  But some fine
sounding scores have been made with my program, by myself and other
users, and we know that good mechanical music doesn't necessarily
require a hand-played roll.

The difference, I suspect, is in details of phrasing and articulation --
especially how long each note is held and then released.  The old roll
cutters and barrel pinners knew how to optimize this, and my program
allows each note to be tagged as legato, marcato, or staccato.  My
program also allows for smooth tempo and dynamic variations -- rubato,
ritard, crescendo, accents, etc.

I wonder to what extent the software that converts sheet music scans
to MIDI reads and interprets all the little Italian directives for
phrasing, volume, and style?  Does it offer options to "swing" the
notes for ragtime and jazz?

Many MIDI sequencers already have a "humanize" or "randomize" option
to take out the mechanical precision.  Unfortunately, too much of this
just sounds like a sloppy pianist, not a swinging one.

What it really should do is not go to MIDI directly, but display its
interpretation of the score and let the human user add all the fine
touches.  The result still won't sound like hand played, but at least
it won't sound like a sewing machine.

--Mike Knudsen