Linux plugin only returns Virtual MIDI ports

Low level MIDI support via Javascript
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kratib
Posts: 4
Joined: Mon Dec 26, 2016 12:55 pm

Linux plugin only returns Virtual MIDI ports

Post by kratib » Mon Dec 26, 2016 3:27 pm

Using Jazz-Plugin v1.5 on Ubuntu 16.04 with Linux kernel 4.4.0-57-lowlatency (64 bits). Jazz-Plugin is installed on Firefox 50.1.0.

Going to this page: http://cwilso.github.io/WebMIDIAPIShim/ ... t_devices/ shows different results under FF + Jazz-Plugin, versus Chrome (with native Web MIDI API support). Specifically, it seems that Jazz-Plugin only picks up the ALSA MIDI ports that are created by `snd-virmidi` kernel module. This is further evidenced by your page http://jazz-soft.net/demo/Connected.html which only shows such ports. Chrome, on the other hand, shows all ALSA MIDI ports including those created by TiMidity, FLUID Synth, in addition to the MIDI Through Ports that are created by `snd-seq-dummy` kernel module.

Am I correctly interpreting the behaviour of Jazz-Plugin? Is there a way to have it sense the other ports too?

Thanks!

sema
Site Admin
Posts: 383
Joined: Mon Oct 17, 2011 7:28 pm

Re: Linux plugin only returns Virtual MIDI ports

Post by sema » Wed Dec 28, 2016 10:12 am

Current version of Jazz-Plugin sees only ALSA MIDI ports.
This may be helpful: http://jazz-soft.net/download/Jazz-Plug ... Synth.html

kratib
Posts: 4
Joined: Mon Dec 26, 2016 12:55 pm

Re: Linux plugin only returns Virtual MIDI ports

Post by kratib » Thu Dec 29, 2016 9:20 am

Thanks for your reply. I had already followed the instructions on the Linux setup page, but that's not what I am asking about. Sorry if I was not clear.

When I use Chrome's native Web MIDI API, it returns all ALSA MIDI ports, including MIDI Through ports and the TiMidity ports.

When I use Jazz-Plugin on Firefox, it ONLY returns Virtual MIDI ports (from `snd-virmidi` kernel module). It does NOT return MIDI Through ports and the TiMidity ports.

sema
Site Admin
Posts: 383
Joined: Mon Oct 17, 2011 7:28 pm

Re: Linux plugin only returns Virtual MIDI ports

Post by sema » Mon Jan 09, 2017 9:44 am

Jazz-Plugin excludes the MIDI-Through from the list. Do you think those are of any use for web applications?
About the TiMidity ports - does aconnect -lo see them?

kratib
Posts: 4
Joined: Mon Dec 26, 2016 12:55 pm

Re: Linux plugin only returns Virtual MIDI ports

Post by kratib » Sat Jan 14, 2017 10:39 am

In my use case, I need MIDI-Through because I am sending my web app's MIDI messages to the MIDI input of another web app, using MIDI-Through as channel.

Here's the output of aconnect -lo

Code: Select all

client 14: 'Midi Through' [type=kernel]
    0 'Midi Through Port-0'
	Connecting To: 128:0
	Connected From: 129:0
    1 'Midi Through Port-1'
	Connecting To: 128:0
	Connected From: 129:1
    2 'Midi Through Port-2'
	Connecting To: 128:0
	Connected From: 129:2
    3 'Midi Through Port-3'
	Connecting To: 128:0
	Connected From: 129:3
client 130: 'TiMidity' [type=user]
    0 'TiMidity port 0 '
	Connected From: 129:4
    1 'TiMidity port 1 '
	Connected From: 129:5
    2 'TiMidity port 2 '
	Connected From: 129:6
    3 'TiMidity port 3 '
	Connected From: 129:7
Attached is what Jazz-Plugin 1.5 finds.
Attachments
Screenshot from 2017-01-14 10-37-38.png
Screenshot from 2017-01-14 10-37-38.png (45.09 KiB) Viewed 4579 times

sema
Site Admin
Posts: 383
Joined: Mon Oct 17, 2011 7:28 pm

Re: Linux plugin only returns Virtual MIDI ports

Post by sema » Wed Jan 18, 2017 12:56 pm

Will post the new Linux version with enabled MIDI-Thru shortly...

kratib
Posts: 4
Joined: Mon Dec 26, 2016 12:55 pm

Re: Linux plugin only returns Virtual MIDI ports

Post by kratib » Fri Jan 20, 2017 8:17 am

Thank you!

Regarding the missing TiMidity ports, I guess the solution is to route them through Virtual MIDI ports as explained in your Linux installation guide?

flyover
Posts: 1
Joined: Mon Mar 05, 2018 7:23 am

Re: Linux plugin only returns Virtual MIDI ports

Post by flyover » Tue Mar 06, 2018 9:05 am

Any word on the Linux version that includes "[type=user]" ports?

sema
Site Admin
Posts: 383
Joined: Mon Oct 17, 2011 7:28 pm

Re: Linux plugin only returns Virtual MIDI ports

Post by sema » Sat Mar 10, 2018 6:27 pm

I got your email and will experiment with your suggestions.
Unfortunately, I don't have any devices that behave like yours - all instruments I tried were visible by ALSA's snd_rawmidi_*

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