About

N.Léveillé (b. 1977, France) programs real-time audiovisual and business software, manages projects, coaches programmers, plays and composes electronic music, and occasionally writes about his experiences.

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nicolas @ uucidl

Trace Event Profiling with chrome://tracing and SPDR

March 14 by nicolas, tagged programming, filed under tools

Knowing more about my code has been a part-time obsession for a couple of years now both at work and outside. Can you really improve what you cannot measure or even visualize?

After some months I had settled with monitoring a certain number of variables in a HTML/Javascript page hosted inside my programs, using the mongoose http server.

However this article from August 2012 made me reconsider writing my own visualization console.

Furthermore, I value very much reusing APIs / protocols (when reusing implementations is not necessary or even needed) and so the trace event profiling API outlined there gave me the needed push to start my own implementation, whose first version I am releasing today: uu.spdr-v0.1.0

It is called SPDR, and allow you to label sections of your code, track the evolution of values with minimum overhead, and importantly in a format compatible with Google’s trace viewer, which almost every one has at their desk in the form of chrome.

The SPDR library is lightweight, compiles for Windows, OS X and POSIX platforms. It is designed to not allocate more memory than you want to use, and supports concurrent traces.

Google’s trace viewer code is also available standalone, which should make it easy to embed in your app.

Changing Things in German

September 20 by nicolas

The girl I’m living with is not feeling gorgeous this morning, and a light blue to electric blue wallpaper-worthy gradient of a sky is showing through the windows of our living room.

The music collection I gathered digitally for a quarter of a sub-saharan african’s life, including a number of dearly loved unreleased tracks disappeared four days ago in a puzzling software mishap.

As the month of September is turning to a close, it’s a good time to make a little personal update here.

On April 2nd I left a flat in northern Prenzlauerberg to walk towards the office of my new employer in Berlin. Had it been April 1st, I would’ve come to this music software company’s office dressed up as a banker, in order to shake up my new colleagues a little bit.

I had moved two weeks earlier from Paris, doing a little bit of tourism and showing the place around. Berlin was already by then quite familiar, having visited friends a number of times the year before, in part due to mistakes made while booking flights. For a month or so I lived with the ghost of an actress-in-making, surrounded by photos, books and weights in a sublet behind the Mauer park. The location was perfect with a 24h Kaiser’s, the park and its flea market and at walking distance from work.

Living in someone else’s place and having to know their lifestyle choices is not particularly enjoyable, and the only contacts with her were through anxious emails repeatedly asking me if everything was ok and if I could forward stacks of mails to her current address, since she was too cheap to ask Die Deutsche Post to do it.

Living in someone else’s place is also not ideal when trying to open a bank account or subscribing to a mobile phone service. Well that latter part went quite alright actually, Simyo delivered the SIM card promptly. ING-DiBa however was another story. It has been a very German experience of exchanging dozens of letters with what claims to be an online service.

To assure a future client’s identity ING-DiBa uses Deutsche Post’s authentication service called Postident, where you are expected to stand in line, walk to the woman in her 50s who will then proceed to give stern looks at your passport, your signature, and your face. I had to sign twice, since my first signature was not similar looking enough, and she did complain about the beard I’m displaying nowadays and which is absent from my passport’s picture. For the first time I had a glimpse at how diligent people here can be when following rules.

Shortly afterwards, it was time to look for a real flat. The plan was easy to figure out: search for 2-rooms south-facing top-floor flats on immobilienscout24, draft emails in the most perfect german I can write, visit appartments. I signed at my third visit. Not because the place was perfect. Rather because it was perfect-enough. It came as is often the case with an entirely empty kitchen, and for those that don’t know, empty in Germany really means empty. It took me three long visits outside of town to settle on a cheap, easy to install kitchen sink, one that would require a minimum amount of sawing/cutting/drilling to setup. Only after drilling the stainless steel surface of my UDDEN sink and assembling its tap, I started to feel I got ahome again.

Until our real move in August I lived in between Berlin and Paris, with minimal furniture and a lot of Skype sessions. A choice I originally made so that I could judge my new city and company and decide whether it was right for me, and also to leave enough time for her to finish what she had to do in Paris.

In the end my 6 month trial period was confirmed and I was more than willing to continue working here. My work colleagues all have different perspectives and personal life stories, coming from very different backgrounds and histories either as choreographers, artists, sound engineers, demo-sceners. Many come from outside Berlin either in Germany or outside (USA, France, Taiwan, Sweden, Spain, Canada…)

Making the most out of what I have at work is motivating. A short 25min walking commute makes it easy to get away, and I like the relaxed atmosphere of Prenzlauerberg. Exactly what I was looking for in the first place. Finding excellent cheese is not easy, and we are under the Bio/Organic cult’s regime, which makes it hard sometimes to get excellent tasting vegetables (my contrarian self loves the look on people’s face when I tell them I’m actively looking for non-bio products) however nothing’s really difficult to find. Besides a good bakery close-by. Oh and don’t get me started on the “Asian” food culture here!

By the way, if like me you are trying to recover some deleted files, give PhotoRec a shot. It’s an amazing little piece of software.

Nathalie Miebach, data manualisations creator

July 18 by nicolas, tagged visualisation and art, filed under commentary

Eyeo Festival had a few interesting and entertaining talks, however I’d like to bring attention to one in particular.

Eyeo2012 - Nathalie Miebach from Eyeo Festival on Vimeo.

Knowing nothing about the Festival, besides that Robert “Flight404″ Hodgins had done a very likeable presentation there, I watched in succession the talks from Ben Fry, Amanda Cox and Nathalie Miebach.

The three of them deal with data visualisation, however Nathalie Miebach was the only one who concretely address the “elephant in the room” of visualisation, which is that although engrained in data, it is an editorial exercise.

And she does it brilliantly and with great honesty.

Her sculpture and her scores naturally embed performance, play, interpretation and the objectivity of measurements. Sometimes she even juxtaposes measurements with her own subjective records, to create hybrid narrative (and quite colorful) works.

Her concluding remarks, that we must not forget to interact with data by touch, also brings to light that we must not let the Ipad or other tablets hijack the meaning of touch, the way Facebook hijacked the meaning of friendship. Touching is not just about finger impacts. It’s as much if not more about feedback.

What's up since October 2010?

April 9, 2011 by nicolas

Hello everyone,

Since last post, I have been invited in november 2010 to do visuals for Windy Hill Mill in Paris at the Gare Aux Gorilles. This was a great opportunity for me to update my live visual code to load arbitrary videos. QuickTime made it possible, on a very short schedule, to integrate full motion videos in my normal OpenGL setup. Unfortunately the place was not ideal for projections, and I ended up projecting onto the ceiling!

Later in January 2011, I also played with my friends of Windy Hill Mill in Brooklyn, NY at the Invisible Dog gallery, bringing some parisian flavour to the show. My setup there was a monome 64 and the MLR sample manipulation program. You should check the photos!

Also worth noting, I did the soundtrack for a short movie by Eva Pervolovici called “Danger de Mort.” A short clashing dreamlike photography with a facetious narration.

Coaching programmers and would-be programmers has also been a very rewarding experience. I’ve been teaching some basics about audio/game programming in C, some methodology, and also been working to demystify the harmful abstractions used in the JSF2/J2EE world. Enterprise programmers’ typical schedule is hindering their progress: Integration, configuration, reading documentation may comprise as much as 70% of their time. Combined with harmful abstractions, this leads to cases of impostor syndrome.

Til next time!

uu:rbrch

October 16, 2010 by nicolas, filed under works

Rbrch is a contemplative piece with an aquatic theme.

Downloads

Each is about 1.5MB big and written in C. Both audio and visuals are generated.

Just contact me if it does not appear to run properly.

Requirements: SSE2, accelerated OpenGL graphics, an audio card.

Video

Although you really should download and run the executable.

Rationale

Rbrch was originally made as a gift for someone’s birthday. A demo meant as a sort of relaxing bubble, away from the urban greyness.

Care was taken in making it work on most basic computers, hence the absence of shaders and an attempt at detecting how fast the machine runs the particle system during the initial blank screen.

Acknowledgements

  • Uses the code base I cowrote for LN2’s.
  • PortAudio provides the audio interface
  • GLUT,GLEW provides the display interface
  • stb_image for image loading

Hope you liked it!