Dear Music afficionados,

I am writing a program (in Java) that will translate tablature into scored music, and vice versa - but thought that once I've done that (I usually get there in the end), it'd be interesting to elaborate on it and get it to translate sound directly into either score or tablature - and of course store all notation thus acquired for hard copy printing.

It had occurred to me though, that such an item might already exist - does it? If so then it isn't worth re-inventing the wheel, so's to speak, else I'll be onto it like a shot. If you've heard of anything like this, could you please tell me, so's I can verify if my idea is original or not ?
Thank you for listening,
Yours, hoping to hear
There are programs that exist for both of your purposes:

Many guitar tabulature programs for example have an option to imprt ascii-text tabs, or convert tabs into notation and vice versa.

There are also programs that will convert audio information (like mp3s etc.) into midi scores (for later tab or notation purposes, etc.). However in that area there can still be lots of progress made, as due to the challenging complexity of the task most of these programs don't operate too good yet. Even writing the basic stable pitch-recognition algorithm is hard, considering that most recordings aren't as clear-cut like midis (think about timing, vibrato, etc..). Especially when it comes to polyphony, that is multiple notes at once, most programs aren't sufficently advanced yet to pick out harmonies reliably.

If you have something to contribute in that field, by all means, do! It will be very challenging
Well, guitarpro can import ASCII tabs and it displays sheet music for it as well, though it doesn't always work that well.

However, if you could make your program

1) be able to translate tablature into music decently and the reverse
2) be able to display & print both forms
3) be able to transpose both tablature and music and for transposing tablature, have an option to simply move all figures up or down x frets as far as possible rather than mess it up totally as guitarpro does

, I'd be a user! Is it possible to make it read music from pdf's, gif's and jpg's? If so I'd love it! And I'm talking about decently "clean" gif's and jpg's, not messy scans.

EDIT: note I don't know of that many music softwares, mainly GP, PowerTab, Sibelius and some more