Michael Sheldon's Stuff

One of the goals to come out of the Jokosher BOF at LUGRadio Live last weekend was that Jokosher should be translated in to as many languages as possible. To this end I’ve now added GNU gettext support and have made a start on a German localisation (hopefully someone with better German knowledge than me can finish this off).

The first release of the Jokosher multi-track audio studio is now available, to find out more about Jokosher simply visit the ‘About‘ page.

Jokosher has a really nice community of developers built up around it (though we’d always welcome more ;)), so now we’d love to see a similar community of users develop. The new site has a forum for just this purpose, so feel free to make extensive use of it for getting help on Jokosher, offering help, discussing techniques, suggesting new features and anything else you can think of vaguely related to Jokosher :).

After many months of abandonment I’ve finally started working on SabreGL again. I’ve rewritten it to make use of the Irrlicht engine; this makes things a lot simpler from my point of view and a lot flashier from the user’s. Irrlicht supports a lot more model formats than I did with my own engine as well as having support for vertex and pixel shaders and is much more reliable under Windows.

SabreGL rendering a BSP:

SabreGL rendering an X model, a height-mapped terrain, a particle source, displaying a 2D GUI and reporting what object the camera is currently looking at:

SabreGL under Windows (lower quality due to software rendering*):

The main thing to do at the moment is sort out how Irrlicht’s event system will communicate with Python, then I’ll see about updating Myrmidia to take advantage of all these flashy new enhancements.

* I’m only testing the Windows build in QEMU so no 3D acceleration is possible.

With all the excitement streaming from Jono and Aq on the subject of things to do with the Nokia 770 that was kindly donated to the Jokosher project at GUADEC, I thought I’d have a play around with the Maemo SDK (Maemo is the platform upon which the Nokia 770 operates).

After a little bit of fiddling I managed to get Jokosher up and running:

It’s not really in a usable state, I had to strip out all the Cairo stuff due to me not having the python cairo bindings installed, but at least it roughly runs :).

I’ve recently been writing code to handle multiple simultanious inputs in Jokosher. Part of this has involved editing Marlin’s channel splitting element slightly so that it works as a standalone GStreamer element separate from libmarlin. Unfortunately it looks like I’m going to have to try and slip my changes in a few days late (i.e. during the feature freeze), if no one has any objections. The work has taken substantially longer than I expected due to me finding that the Delta 44 doesn’t work with GStreamer, I’ve since filed a bug and created a rough patch for the problem. I’m still having one problem though, which is that I’m only receiving data on the mixed input channels from the Delta 44 and not on the individual ones. I’m not sure if this is a problem in alsasrc, in the channel splitter or in my use of either, but at least the Delta 44 is now usable as an input device in GStreamer (albeit not without the channel splitter, since hardly any elements support 12 channels).

In related news Jokosher has been used to record a LUGRadio mini episode, which has also helped to find some new bugs.

I’ve also recently purchased a Roland GR-20 guitar synthesizer, which has given me new drive to get Delta 44 input fully sorted in Jokosher. I have various odd musical ideas I’d like to record with it and Jokosher would be the perfect application to do so with.

As part of the Jokosher hackfest, which is happening as I write, I’ve finally sat down and mostly sorted out the channel splitting element. We need this element for handling multiple simultanious inputs from a single sound card due to them coming in as a single multi-channel stream and us needing lots of single channel streams. An example of its usage would be roughly along these lines:

                  |-- chansplit channel=0 -- etc -- filesink location=0.flac
                  |-- chansplit channel=1 -- etc -- filesink location=1.flac
alsasrc -- tee -- |
                  |-- chansplit channel=2 -- etc -- filesink location=2.flac
                  |-- chansplit channel=3 -- etc -- filesink location=3.flac

It’s not quite perfect yet, it should really output a stream with a single channel instead of just moving the selected channel to position 0 and silencing the others, but it’s usable. I’ve created a package for Ubuntu Dapper (should work on Debian unstable as well): gstreamer0.10-chansplit_0.10.1-0_i386.deb and the source is available from the Jokosher subversion repositories.

In related news, ensonic has just fixed a bug in GStreamer which was preventing playing a project multiple times in Jokosher, which is great :).

Davy Graham’s Anji again, but this time played somewhat better and on my acoustic guitar instead of my electric.

Anji Acoustic – ogg vorbis
Anji Acoustic – mp3

Thought I’d give another little update on what I’ve been doing on Jokosher. Over the past couple of days I’ve added support for Gnonlin based mixed playback, event based recording, displaying of recorded events and (buggy) exporting. After the export bug and a problem with start/duration settings for events are sorted it’ll actually be vaguely usable, though still rough around the edges and lacking a lot of features. The rest of the team have been doing amazing things with the GUI, making it look and feel really nice, as well as getting saving and loading working pretty well.

Latest screenshot:

I noticed a lack of any software that deals with mouse movement smoothing for people suffering from Parkinson’s Disease, Essential Tremour, and similiar conditions that works under X. There already exists some software called SteadyMouse for Windows, and IBM make a hardware adapter.

So I decided to have a go at writing something. It’s only had a few hours work on it so far. It implements some simple low pass filtering to try and remove shakes and isn’t especially good at the moment (in fact it might even make things worse :P) but it’s a start. I probably won’t do much more on it until Easter when I’ll have a computer with an actual mouse instead of a trackpad to experiment with but the current code is available in my bazaar repository.

Here’s a screenshot:

(Notice the cute hamster systray icon ;).)

Alasdair has been doing a great job keeping the Jokosher website updated with the latest progress, but I thought I would write a little post here since it beats actually working.

We’re now well on the way to getting everything ported to GStreamer 0.10 (from 0.8), which already shows noticeable speed improvements (the interface is now much more responsive when recording).

I’ve written some HAL/DBUS code to automatically detect what sound cards are available and allow the user to select them in the preferences dialog (although this selection isn’t yet used, I’ll have that done fairly shortly).

Ben Thorpe has started hacking on things a fair amount, adding selection and deletion code as well as fixing some irritating bugs.

Alasdair has been redesigning the website slightly, creating a new image for the header.

A few new people have expressed an interest in helping out, no doubt lured by Jono’s fame as the rest of us poor souls were ;).

We now have a tentative release date for 0.1 sketched in as the 22nd of July, to coincide with LUGRadio Live ’06, at which Jono ambitiously hopes to be able to record the show’s audio using it (plus we can hijack lots of people for a release party ;)).

Finally, a screenshot, made all the more pretty by Dan & Greg’s icons.