Advogato blog for ensonic

10 May 2008

Sat, 10 May 2008 12:18:10 GMT

buzztard

As can be seen on our roadmap sample support is scheduled for 0.4. As this is the major feature, we started working on it. I have to say that building buzztard on top of GStreamer was definitely the right thing to do. We can now load whatever GStreamer can handle. FSM did a nice cairo-based waveform widget. Right now I am working on the code that allows plugins to access the wavetable. It will hopefully be ready real soon.

Besides that I've started to restructure the gst-buzztard package a bit further. I also plan to merge the buzz wrapper plugin into it. The aim is to reduce the number of packages that one needs to build.

12 Apr 2008

Sat, 12 Apr 2008 20:05:21 GMT

After the release I demoed it some friends and obviously found some issues. Now I spend the rest of the month tracking then. Its mostly ref-counts issues. Why are the so nasty? Well unlike memory leaks, they are anonymous. Memory is allocated once and should be paired by one free. The id of the resource is the memory address. Now every ref should be paired by an unref, but all the refs and unrefs share the same id (address of the object). So how to figure which ref is not having the unref? Refdbg can trace object and gather backtraces for ref-count operations. So one has to go through the list one by one, remove pairs and study whats left. Its not easy, but it works. Now why is this so important. If the refcount never reaches 0, the object is not disposed and occupies memory (until the application exits). Under valgrind it would appear under reachable memory usually. For most apps it has no immediately visible effect. For gstreamer app it has. In buzztard I do dynamic stuff with pipelines, like adding and removing elements. If you get the ref-counting wrong. The element is unlinked but not disposed. If the pipeline is set to PLAYING one gets data flow errors. But then its not a gstreamer only problem. E.g. icon theme pixbufs in gtk. If the are not unrefed, gtk cannot unload the theme. Means if you try a bunch of themes, none of the is unloaded if even just one panel applet has a ref-count issue. The sad thing is that the gnome libraries have quite some ref-count leaks. I've started to track and fix them as its hard to see something within all this noise (#525815, #66513).

I've released buzztard-0.3.1 with the fixes. A few more developments to mention: Waffel started a demo for the zip loader based on libgsf, Deloun made great svg designs for the machine view canvas and the tabs and Herzi send me a patch to add native scrolling in the pattern editor. Now back to new features, yah!

27 Mar 2008

Thu, 27 Mar 2008 18:12:15 GMT

The buzztard team has released version 0.3.0 "a tale of ice and darkness" of its buzz-alike music composer. All modules got extensive improvements over the last release from almost a year ago. It is usable now and fun to play with. Give it a try and report bugs.

bml : Support for native machines. Better emulation. Can be build on 64bit x86.

bsl : Support for pre 1.2 buzz songs. Handle volume and panorama on wires. Several bug fixes.

buzztard : Improvements in all areas. We now have native buzzmachine support and better compatibility. The buzztard editor got an own pattern editor widget. The ui got lots of keyboard commands. We have settings for default directories used. The ui has dialogs for recording mix-downs and also single tracks.

gst-buzztard : Improvements on the preset interface. Support for sparse streams (GAP flag).

gstbml : Sparse stream handling. Better compatibility. Bug fixes.

project-page - screenshots - downloads

6 Mar 2008

Thu, 6 Mar 2008 19:30:33 GMT

buzztard

The Linux Audio Conference 2008 was nice once again. Good talks, interesting know-how exchange and of course opportunities for testing and hacking on buzztard.

I have improved the playback engine a bit. It now uses less additional latency. Still one get much lower latency by using jack, instead of pulse audio (currently experimenting to lower latency there too).

The pattern editor got better gtk+ theme support (especially on dark ones) and also tries to use the default monospace font and font-size to better match with the overall look of your desktop. I implemented blending value ranges and randomization of ranges. FSM implemented more keyboard shortcuts. I added value descriptions to the status bar where the plugin supports it.

Also the sequence editor got some todo-fixing. The sequence was never horizontally scrollable (adding columns would force the window to be wider). The M,S,B buttons are now color shaded when pressed to give better visual clues. Finally also the position unit switcher is functional (ticks/time) and the label navigator gets properly updated. Lots of small things I never got around until now

Level meters in sequence and analyzer windows are now more lively and precise. Having several analyzers open now also produces the expected results.

The buzz song importer got further fixes. It seems to load all of my songs just fine now.

Some improvements also on the buzz emulation side. More machines load and work. We have a nice testsuite with html reports now. I spotted some issues which will fix more machines. Will try to implement this next.

If nothing urgent comes up. I'll prepare the release in the coming days. Stay tuned.

7 Feb 2008

Thu, 7 Feb 2008 20:42:50 GMT

buzztard

We're heading for a release. There is a few more features that we'd like to finalize. Then its time for testing and this is were *you* can help. Featurewise buzztard improved nicely this month. I improved stereo support. We now have new look for the wires. They show animated volume levels and panorama positions. Both volume and panorama can be adjusted via popup-sliders.I like this a lot more that how it works in buzz. There it was a bit confusing in some cases (not clearly indicating which connections a panorama setting would affect). As an extra bonus, buzztard does stereo balance on stereo connections.

I also updated the buzz song importer to make use and correctly import panorama and volume. Now also the master-volume is mapped to the scale used in buzztard.

FSM worked on the pattern widget. It supports variable cursor stepping (going down several lines at once) and selection. I added column/group/all insert and delete actions.

Finally Waffel wrote a jhbuild module set for buzztard.

8 Jan 2008

Tue, 8 Jan 2008 20:21:03 GMT

buzztard

I guess tracker-style music editors have to live with the heritage of tabular pattern input. Some feature rely heavily on it. FSM started with such a widget and I integrated it into buzztard. One can still switch between the previous and the new one by setting a define. The widget works quite nice already. The only missing feature is native scrolling support. To add that to an own widget requires an ugly hack. I can't figure why gtk does not use an interface for it.

Patterns in buzz also carry volume and panorama events for the inputs of the machine. This was totally missing in buzztard. Now we have quite nice support for it. The volume control works and panorama/balance support is next on the to-do list. While working on that I made master-machine patterns useful by allowing to control master-volume,

The sequence view got more commands. Finally one can insert and delete rows in all columns or only in the current track.

If that wasn't enough, we also did a round of maintenance. All code has been moved to svn. The buildbot has been extended to build all modules now. And finally I got around to port the code to not use the deprecated gtk tooltip API if new gtk is available.

That's a great start for 2008 I'd say!

3 Dec 2007

Mon, 3 Dec 2007 19:17:47 GMT

buzztard

After porting some simpler machines last month, FSM and myself where looking at infector. This already is a quite complex generator. Porting as such wasn't that hard, but unfortunately it did not play. But with the sources at hand we could figure out what the issues was and fix the problem. It was a generic problem in the buzzmachine host emulation. This could potentially also make other machines work. Note to myself - I need to re-test the blacklisted ones. One outcome of the better machine compatibility is that some of the original buzz song now plays with some extra manual help.

Some improvements on the UI side also. The spectrum analyzer window is now re-sizable. We also have a workaround for a gtk+ bug [1], there is now an accelerator to start playback.

Unfortunately my recent attempts to merge my preset iface [2] to gstreamer got stopped again. I need to try harder poking the other developers to review it.

That's it for this month - happy x-mas month to everybody.

10 Nov 2007

Sat, 10 Nov 2007 18:55:54 GMT

buzztard

Very good news for buzz lovers. Recently FSM joined #buzztard irc channel. He gave us access to his buzzmachine sources and the okay to publish them under LGPL. One thing that I had on my list for too long was to extend my buzz-emulation layer to support natively built buzzmachines. Well now its in CVS, A bml/gstbml rewrite to support native machines + initial 5 machines working. Means approximately 900 to go. One thing that we need to be able to port some machines is a native implementation of buzz's dsplib. We will look into that next and of course port more machines.

Some small progress also in the UI. I've added track reordering in sequence tab and keymap independent note entering (y vs z mapping on different key layouts),

20 Oct 2007

Sat, 20 Oct 2007 19:17:53 GMT

opensuse 10.3

Its the time of the year when I ruin my setup by upgrading my opensuse box. The actual upgrade went surprisingly smooth. The only hickup was that all disk are now named sd* instead of hd* and the setup was not prepared to update grub. With some manual intervention on a console and changing the settings by hand I could proceed.

The reboot worked fine and it thought for a moment that everything is fine. Its not:

333999 gnome-control-center missing in the menu
334050 gnome window decorator does not show the application icon
334062 gnome-xgl-switch and white desktop </a>
334081 totem has support for plugins, but they are missing in the package
335267 /etc/init.d/kbd: setfont: putfont: 256,8x16: failed: -1
335491 gnome-session hangs on logout

I also filed some for the gnome components:

486873 Evolution: Switching the shown category in contact view kills or hangs evolution-data-server
488663 gnome-panel: gtk_recent_manager_add_full: assertion `uri != NULL' failed
488710 gmenu-simple-editor: errors in .xsession-errors

Some reports got comments already and and some got info from my side of how to fix it, for some I am still in the dark. Lets hope they get addressed quickly and fixes are made available via online-update. The evolution bug worries me, a bug report with a backtrace for a double free, that is low-hanging fruit, but no one commented yet. Regarding the gnome-panel one, there is quite a lot of stuff in the .xsession-errors. Is that simply the stderr of everything started from the gnome-session? Shouldn't we require apps to somehow prefix their output with a domain (or use g_log methods instead of fprintf).

17 Oct 2007

Wed, 17 Oct 2007 15:47:25 GMT

gstreamer debugging support

GStreamer pipelines can quickly become quite complex. Even a simple video playback pipeline easily plugs 20 elements. Now ts something goes wrong, developers had to go through zillion lines of log-output. Now there is some help:

Today I committed the code for #456573. All it needs is a simple macro in the code. The graph dumping gets disabled for non-debug builds. When running use GST_DEBUG_DUMP_DOT_FILES=1 in the environment to activate it. It dumps several graph by using timestamps in the filename. To get e.g. the png from the graph one runs:

dot -Tpng /tmp/gst-launch.0:00:00.984100000.dot -o/tmp/gst-launch.0:00:00.984100000.png

If now apps like totem, rhythmbox and co. put this into the handler for warning and error bus-messages, we have a nice way to track down playback problems.