Retracting your question shouldn't deny others the right to answer it, especially in a public forum where the answers might be helpful to someone in the future.
jesus fuckin christ Splashman gave you the closest to a GSF to MIDI converter there is...
But then again, "nevermind", so obviously you don't want the GSF to MIDI converter anyway, so kindly make your way towards the "back button".
GBS to MIDI by Splashman at 4:23 PM EST on January 26, 2013
badump
Since there is no GBS to MIDI converter, I guess the only other way is to use GBA2MIDI with a Goomba converted GB ROM (GBS -> GB -> GBA). However, it looks like GBA2MIDI does not support Goomba ROMs without the proper ROM ID and offsets in the ofslist.txt list. Does anybody know how to extract them, or if my method is even possible? I need MIDIs from Megaman I-V.
I'm hardly an authority, but I get the feeling that you won't be able to get GBA2MIDI working with that Goomba ROM. I mean, I see what you're trying to do, but I'm pretty sure there's going to be at least one insurmountable wall no matter what you try with this process.
While perhaps not as reliable as GBA2MIDI ideally would have been, you could always create a VGM set for the games, then use the latest WIP version of vgm2mid to convert the VGM files to MIDI (you might not even have to do all the cleaning/trimming normally involved in making VGM sets).
Of course, creating VGM sets takes some time and can be a pain, but it's a simple enough process once you have the modified version of MESS. Since GBS2GB seems to render ROMs out in a 'normal' file size, you shouldn't need to pad them any. Just make a savestate for the start of the track you want and then load that as soon as you start the game.
(note that this is currently all just theory unless I can confirm it later, but it should work)
I see, so the process would be GBS -> GB -> MESS -> (VGM) -> VGM2MID -> MIDI?
I am familiar with VGM logging from SEGA emulators, but I don't happen to find the setting in MESS.
I've gotten as far as saving a memory state in MESS with shift-F7, but now all I have is a .sta file. What do I do with it next, or am I missing something?
ah, I should have specified. You need to use the modified version of MESS linked above, which will start logging to a VGM file as soon as you load a game. There's unfortunately no in-emu control of the logging other than starting/stopping the emulation, and you may need to enable "vgmwrite" in the config file you generate.
It logs a different VGM for each system emulated, but it will overwrite that file each time you emulate that system. That's why you'll want savestates at at a point where a track is about to play (preferably after a button press), and load those right away. It's a pain compared to logging from various Sega system emulators, but it's the only method I can think of unless the GBA2MIDI process gets figured out somehow.
I'm sorry, but I'm fairly sure a VGM to NSF conversion is basically impossible - at the very least, it would require someone who is an absolute expert at manipulating both formats and who knows exactly what programs to use to achieve what they want. I suppose you could rig something together if you knew every bit of data about the music and worked through transcription formats like MIDI/Music Macro Language (MML), but at a certain point you would simply no longer be preserving/emulating the original sound data. It's certainly wouldn't be suitable for archiving on sites like the ones Knurek is building.
The problem lies in the fact that VGM files and NSF files are two very different ways of emulating music. An NSF contains notably more data than a VGM, usually storing the game's sound engine, any instrument samples and all the games music sequences. A VGM is an individual sequence from a game that is "logged", kind of like if you were writing down a song you were hearing in musical notation. It does a number of different things different from NSF - for example, an NSF usually stores each instrument sample a single time and plays it when the sequence data says it should. A VGM, on the other hand, stores the sample in the log every time it was played by the game - this is why VGM files can be quite large before (and even after) they are optimized.
When you dump the VGM to MIDI, it only pulls the "sheet music" it sees, not the instrument samples that actually reproduce the sound of the game.
So I may not be expressing or explaining this properly, but you really can't convert from VGM to NSF.
As for YM files...geez, you don't hear a lot about those. Unfortunately, I don't know enough about that format to talk about it, although it seems to be a logged format like VGM. I also get the feeling you won't be able to convert from VGM or log via MESS. It was only through ValleyBell's interest that VGM logging was injected into MESS, and presumably he/she isn't interested in doing something similar for YM files.
Minor nitpick - we have had at least one rip that used logging instead of game code (Gran Turismo for PSX IIRC), so it's possible. Not really that feasible, but certainly doable.