Midipal filter editor: how to run it offline/locally?

the midipal filter editor is available as an online web app.

is there any way to run it on a windows machine without internet access?

the source code is available here, but i don’t know a thing about coding. so please forgive me if this is a stupid question: is there any simple way of running that code locally?

Have you tried dumping/downloading the website?
Not sure if it is running some sort of engine in the background(serverside), but that would prevent the above approach from working. Still worth a shot…

  • Download the Google AppEngine Python SDK for Windows.
  • Download the MIDIpal source code from github.
  • Launch the GoogleAppEngineLauncher app.
  • Select the “Add existing application” command in the “File” menu.
  • Select the editor directory from the midipal source code in the Path selector.
  • Click “Run”. The editor runs at the following URL: localhost:8080.

cool, thanks!

just gave it a try: seems to be running fine.
just one minor formatting glitch:
in the rightmost column of the 4x4 midi channel selection grid, there is a “” visible behind each channel number. i.e. it says “4” instead of “4”, “8” instead of “8” etc.

oh, and the link to the “retrieve” page is missing.

Did you ever sort it out, I am also interrested

Hello, the editor seems to be no longer available online but I would really need to use it. Where can I find it?

Also the instructions from @pichenettes seem to be outdated.

The site is offline for the same reasons the instructions posted above (in 2014) are outdated: Google AppEngine has received updates upon updates, breaking the compatibility.

It is currently not my priority to fix this, if someone wants to give it a try, the code is here: midipal/editor at master · pichenettes/midipal · GitHub

Belated thanks for the prompt reply. My python skills aren’t more than making an arithmetic calculation and printing it, otherwise I’d gladly help out.

Anyway, for now managed to find a workaround using the channel fitler!

It’s back online here:


To run the editor locally from the root of the midipal git repo:

python3 -m venv env
source env/bin/activate
cd editor
pip install -r requirements.txt
python main.py

Also brought back to life the Yarns scale editor. https://scale-editor-350013.ew.r.appspot.com/

1 Like

Hi @pichenettes ,

it seems requirements.txt is missing in the repository…
Anyways thank you very much, everything is working fine after installing Flask manually.



Wow, that was fast :smiley:

Thanks again!