Add MIDI output support

[CrushedPixel]

Closes #15.
@steveschow Please build and test whether this suits your needs - I wasn't able to find a free MIDI processing AU/VST within a reasonable time.

[dawtech]

Thanks I will try this out today.

[dawtech]

I actually do have one question about how to try out your change...not experienced enough with github to know how I can pickup your change into my local repo to build it, my repo is just cloned from the main plugalyzer repo... how do I go about getting the version to build that you are submitting now as PR?

[steveschow]

never mind, think I figured out.

git pull
git checkout midi_branch

will try it out today

[steveschow]

I attempted the following and reported error, might be the way I'm using it, please clarify:

Plugalyzer --midiInput=./testmidi.mid --midiOutput=./output.mid --overwrite process --plugin=/Library/Audio/Plug-Ins/VST3/Melodya.vst3
At least 1 option from [-i,--input,-m,--midiInput] is required
Run with --help for more information.

[CrushedPixel]

At least 1 option from [-i,--input,-m,--midiInput] is required

The tool is telling you what it needs - it currently expects you to supply either a MIDI or audio input file. This is needed for Plugalyzer to determine the length of processing. If you don't need MIDI or Audio input, simply create an empty audio or MIDI file of the desired length and feed that to Plugalyzer.

[steveschow]

Yes but look at the command line I used. I thought I did ?

[CrushedPixel]

Yes but look at the command line I used. I thought I did ?

My bad. You need to write the subcommand (in your case process) directly after the Plugalyzer name.

[steveschow]

Ok, so anyway it reads the midi file and outputs an empty one but none of the midi plugins I have currently available (including my own) will output any actual midi without some manipulation of the GUI. one of them ought to be outputting some midi, but its not and I'm guessing it must be something related to the fact that there is no transport playing? Often times I have midi effects that are specifically coded to only do what they do while the transport is actually "playing". I am just guessing, but perhaps Plugalyzer is not setting transport status on? Well anyway, if you get that VSTPRESET feature working, then it may be easier to load a plugin along with a preset and then have some behavior, but unfortunately I don't have a way right now to test if Plugalyzer is actually working correctly since the output midifile it produces right only doesn't have any midi events...but that can very well be because the midi plugins I am trying to test require at least a preset loaded to avoid having to interact with the GUI...

I might try today to see if I can find some of those old piz midi plugins, which I think are quite simple and may be able to some some simple midi filtering tasks without preset involved...and at least verify plugalyzer is working...

the vstpreset feature will help a lot.