I'm just recovering from the picnicnetwork.org conference where I forged some new contacts and renewed many old. The week before picnic we had the chance to build and design interactive installations presented at the conference in a 5 day hackers-camp. We rented a house with 30 people and as you can imagine there was little time for sleep. Besides supporting the camp on oAuth and anyMeta. I've added the breedr on my ToDo stack: A pond filled with sand in which virtual creatures dwell in an environment linked to the internet-world; reacting on internet-traffic, user-profile-changes or interacting directly via RFID triggers. Come with a friend and cross breed web-DNA to make a link.

The source is online at the breedr trac, read more on our project page. Mediamatic has the picture.

I'll cite my friend Luis, whom I teamed up with for the Breedr project: «The group of people that have shared a roof over the last week is pretty amazing. The array of skills, the variety of views, the camaraderie and the relentless commitment on parade over the last week are truly awesome.»

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Since Friday I'm hacking almost non-stop for the picnic conference where registered conference visitors keep their online-profile on a RFID-chip (ik-tag or i-tag) which they can use to sign up for workshops, participate in games, make friends/exchange contacts, get consumption vouchers, etc. throughout the conference.

Besides being back coding for mediamatic's anyMeta CMS (here: Community Managemet System), I've teamed up with Luis, Sly, Thijs and Neil to build The Breeder: an installation where you can interact with a virtual creature that «lives on your RFID tag».

Besides feeding the creature with input from your personal-profile and online activity, you can meet with your and other creatures for reproduction at a pond-like portal (beamer, pond with white sand, camera, rfid-readers) that will be exhibited during the conference staring next Wednesday. The Breeder will visualize meta-activity of conference-visitors in a game like environment (processing/java) where creatures can reproduce when their owners meet and recombine genes of their profiles. Furthermore interaction is not limited to the pond: Users can download a screenshot/snapshot of their pet or enter a communication that their creatures stroke up.. - I'm out to walk my amoeba.

It's a very ambitious project, even more so given a 5 days timeframe from idea until deadline.. You can follow development at our project trac/wiki.

Yet another Sunday without sun in Amsterdam… I spent the afternoon fixing an issue with empty URL paths for liboauth.

After scraping the documentation I choose to

insert a slash before the [first] '?' (or '&' or end of string) if and only if
there is no '/' between the protocol's /:\/[\/]*/ and the delimiter.

It looks like a dirty hack, but checking the BNF this seems perfectly ok. All slashes in the /authority/-part of the URL (userinfo, host) should have been escaped. This was too easy and I had still some coffee left, so I went on to tackle RSA-SHA1 signatures and other open ToDo items..

Openssl gave me quite a headache, that got resolved over an Indian dinner with Florian; he's just back from CERN - angry against bloggers who misinform about the LHC - carrying the spirit of Johnatan R. Ellis: the web strikes back.

With a deep sigh, I've released liboauth 0.3.0 last night. It's the first version that implements the complete oAuth-1.0 spec. I went over four version steps, adding missing functions and a oAuth consumer example. I was tempted to call this a v1.0 or at least v0.9 which may happen during the next weeks. I'm in contact with Marc Powell about integrating liboauth with curl; and the code will definitely come in handy for implementing apache's mod_auth_oauth.

The magic mirror v2.0.0 - I just made that SVN tag and started wondering about the name - will be presented this Friday (July 11 2008) at Montevideo - the Netherlands Institute for Media Art (http://nimk.nl) in Amsterdam - the opening is at 17.00.

Frontera is a fancy combination of video-recording, hand-detection and video-projection: It allows the user to interact with a person projected on a touch-screen, where the projection follows the hand of the player. It takes about three minutes to record an avatar of oneself (wiping the screen) and there are two installations at Montevideo allowing to play and record.

We've had lots of fun and finally got to do a few good recordings of ourselves - come and play at the opening or later.

The last days have been busy, there are last minute changes on the frames and we still need to do a final calibration of justpoint. - I spent most of today tweaking the GUI to avoid reflections (of the monitor while recording) but we've managed to cover miles in the last days and even made a small webinterface to browse the recordings… - the software devel went quite smooth, we've made a few extras that we don't need and if I get the time i'll optimize the query for movement detection. - worst task: recalibration after zooming or panning the recording camera.

read more frontera.

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Categorizing linux audio applications

As a first step to clean up the tag mess at http://apps.linuxaudio.org I started to visualize “the problem”. It turns out there are ~1800 tagged pages with ~200 unique tags¹⁾.

Most of the tags go back to headlines in the original data of linux-sound.org. All applicable headings (<h1>..<h5> and <li><b>..) were used as tags for a given link in a flat structure. However interrelations between the tags (headings) have been maintained by tagging the tags themselves. 57 of the 203 tags are not tagged (orphaned, loose), these are either top-level-tags or new additions that have not yet been categorized. An index of all tags can be generarated at apps.linuxaudio.org; a text-file is available with the sources below.

The most commonly used tags are:

  154 software_sound_synthesis_and_music_composition_packages
  145 other_documentation_and_newsworthy_items
  137 all_things_jack
  119 midi_software
  115 linux_audio_tools
  113 tools_to_make_tools
  110 signal_analysis_processing_software
  102 on-line_articles

Conclusion

I trashed the initial intention to reduce the number of tags to a manageable amount. On the contrary: some of the multi_word_tags shall be broken up, and the overall conclusion is: We just need a better user-interface to browse and assign tags.

dokubookmark already prototypes a check-box interface to manage tags. For the apps-wiki a tag-cloud or hierarchical display would be needed to ultimately improve usability.

More discoveries

Now made visible, I discovered a bug in the tag-inheritance parser which imported the data from linux-sound to the apps-wiki. There are additional false tags to content where a sub-level heading was not closed. Most prominently affected are SOAL and openAL.

I'm pondering on a re-import of the data but that would require magic to merge the updates. Magic is the cue, so I'm now writing a perl-script to manage, rename and clean up the tags: dokutagitor.pl

Source

The data was generated from the wiki-content (dokuwiki text files) using this greppy shell-script and graphviz. The png/jpeg images turned out to be rather large (2400×2200 pixel ~2MB). I suggest you download look at the SVG or render images from source.

• SVG image of all tags
• SVG image - only categorized tags
• SVG image - only loose tags
• graphviz ''.dot'' sources - unzip and process eg. fdp tags.dot -Tpng > graph_all.png
• lao-tags-list.txt - text file with all tags

Legend

The color of each tag gives a hint on how often it is used. This value is also printed in brackets after each tag-name. red color increases with more common usage. white indicates end-points and the shades of blue/green jump at usage-counts < 20 , < 40 , >= 40.

Arrows should go from parent topic-tag to child tag - but the current script does not filter out back-links so the direction is more or less random. it is not relevant for this analysis anyway.

..so what have you done on 8/8/8 ?

I spent the morning reading http://dyne.org/first_dharma_dyne.pdf and been hanging out at Nadya's good by party: Lucky girls attend MIT in roaring 1920 style.

Much of my time the last days went into linuxaudio.org and related endeavors: On the WWW front I set up a public git repository (using gitosis, gitweb and git-daemon) running on http://git.linuxaudio.org/ , updated the dokuwiki at http://apps.linuxaudio.org/ and for good measure threw in an ABC-MIDI tutorial on the upcoming linuxaudio.org wiki.

During the thunderstorm and a short power-outage in Amsterdam Oost (offline!) i gave the 2.6.26 realtime kernel a go and continuted to discuss why it does not work.. ;) - Oh and I've coded a first native OSX-quartz display for xjadeo on my girl-friends Macintosh and can't wait until she comes home so I can take a screenshot - I never though I'd hear me saying that - Thus no screen shot, it'll take me at least two weeks to complete it anyway.

I'll be working on an open source implementation of Lilian Prerez' Frontera project at the NIMK.

Frontera is a touch-screen that projects a pre-recorded video of a player touching the screen at the same position as the user. I'm going to do the whole installation (hand-detection, recording and playback) from-scratch together with Arjan Scherpenisse. the sources will be on sourceforge. - stay tuned.

I've been asked to do a surround sound installation for the ..and Beyond fashion show “Spectacle” in Amsterdam, gonna be fun.

We finally made it to share social network information, articles, and news via Publish/Subscribe XMPP with the anyMeta4 CMS

A small step for mediamatic but a large step towards data-portability ;)

just spent half a day updating this dokuwiki!