Although importing from midi to a notation program often looks like someone threw a fistfull of maggots on the pizza, when the midi was made by exporting from a notation program importing the midi back into a different notation program is often pretty clean.

This makes it a reasonably convenient method for getting from one notation program to another, but if you don't have the midi it does require access to both programs - one to make the midi and the other to make the midi into a new score in the format of the other one.

Since lots of programs export/import midi, but don't recognize (m)any other notation formats it's sort of a way to "generalize" conversions from one notation format to another by "passing it through" a midi.

The midi exported from notation will have all the notes "quantized" with the durations in the notation, and in most cases they'll come back into any other program with the same durations as in the original. You may lose "ties" and such, depending a little on how sophisticated the notation program that imports the midi is.

The one thing that won't come back is "repeats." The midi will contain all the notes in the order they're sounded, so if a repeated phrase is played "into the midi" it will come out with the repeated measures tacked onto the end of the first pass.

Generally, the more "mechanical" the midi sounds, the better it will convert back to notation, so "pretty music" doesn't give very pretty results.

Since ABC is about as "mechanical" as notation, a midi made from ABC should import to a notation program to make a fairly decent score in standard notation.

About the only way to really tell what you'll get from a random midi is to "suck it into the program" and look at what happens.

John