Archive for August, 2012

As the crow flies

Tuesday, August 21st, 2012

I went this weekend to see the brilliant immersive soundscape installation The Murder of Crows by Janet Cardiff & George Bures Miller, currently showing at the Park Avenue Armory. If you will be in NYC between now and September 9, I highly recommend it!

Essentially a dreamscape audio movie realized by 98 speakers placed around the Armory’s immense Diff Hall, the experience reminded me of the huge emotional power that sound can convey. I could literally feel, in my bones, doors creaking open and closed, marching footsteps, howling winds and other powerful sonic “images”, with a visceral immediacy far beyond what could be conveyed by mere visual means.

And of course I immediately set about trying to figure out how I could make one. It could be done with a binaural headset, but I wouldn’t want to have to wear earphones all the time. With a stationary audience of just a few people, you can do it with four speakers, each positioned at the corners of a square around the listeners.

To capture the soundscape, you would use four microphones arranged into a square exactly the same size. If pairs of microphones are the wrong distances from each other, then phase information is destroyed, and the experience will lose realism and immediacy. And you probably want the square to be fairly large, so it captures the way things move between the speakers.

So a faithful audio “camera” partly comes down to placing each microphone the correct distance away from the other microphones as the crow flies (so to speak). If you are doing this in a secluded location (eg: a beach), then you can just use six strings of the proper lengths — one between every pair of your four mike stands — and separate the mike stands until the strings are taut.

But if you are doing it in a crowded place, such as a New York City street, then you need to use some other method of calibrating distance. You could use optical measuring devices, such as time-of-flight cameras, but to me that seems needlessly expensive.

Since we already have high quality microphones, perhaps we can generate a sound and measure when that sound arrives at each microphone (a simple form of sonar). As a calibration device, we can place two small speakers a small known distance apart from each other (say, on opposite ends of a separating rod). A computer sends two simultaneous pings, one to each of the two calibration speakers — with the two pings having different pitches. From the time each of the pings arrives at each of the four mikes, we can calculate the exact position of all four mikes, and how each mike needs to be moved to get into proper position.

I’m sure there are other ways to do this. The important thing is to be able to capture wondrous immersive soundscapes wherever they may be. If a library of such immersive soundscapes could be developed, then this would be an experience anyone could enjoy at home.

Two haiku

Monday, August 20th, 2012

If each of us looked
Like our soul, and kindness were
Treasured as beauty,

Would that be a world
Where war could never exist?
Imagine that world.

Assembling spheres with magnets

Sunday, August 19th, 2012

I am circling back to the problem I described last October of tiling a sphere with identical puzzle pieces, because I’d like to be able to quickly put together things like portable planetarium domes and big acoustic focusing mirrors. Ideally I’d want to be able to carry something small and portable, and then put up or take down the resulting sphere very quickly.

If we go with the identical puzzle piece approach, then a sphere requires 60 slightly curved shapes (or 30 shapes for a hemisphere, if you want a planetarium dome). In its disassembled state, the sphere would consist of a stack of identically shaped pieces. I’m thinking that a nice way to make something both stackable and easy to assemble/disassemble would be to put tiny magnets along the edges.

You’d want to orient the magnets, as in the diagram below, so that the pieces stick together properly both when assembled and when disassembled / stacked. One way to do this would be to orient four magnets (shown as red dots) so that the north poles of two magnets point out of the sphere, and the south poles of the other two magnets point out of the sphere:

While this scheme works, it requires a lot of tiny magnets — four magnets per piece. That’s 120 magnets for a dome, and 240 for a full sphere. Fortunately we can replace half the magnets with small pieces of metal (shown as blue dots below), which are cheaper:

Now all that remains is to build the thing and see if it all works. :-)

New York in summer

Saturday, August 18th, 2012

New York in summer
Becomes a perfect playground.
Too bad summer ends.

Anecdotal

Friday, August 17th, 2012

I was recently having a conversation with two very intelligent and politically well-informed people, both of whom were shocked when I said that I knew from first hand experience that parts of our federal government are not corrupt. My friends were shocked not because they believed me, but rather from astonishment that I could be so hopelessly naive as to not realize that our government is rotten to the core, a hopeless miasma of stinking corruption, with everyone on the take.

In a wish to help me through my unfortunate gaffe, one of my conversants helpfully pointed out that my experience was, by definition, merely anecdotal, and therefore could seem real to me while not actually bearing any relation to reality.

It took me quite a while to realize what was going on in the conversation, and then only a bit longer to take them through the nature of my experience. I explained that my experience has mainly been with the NSF. Over the course of many years, interacting with an extremely large number of program officers, I have found every one of them not only to be scrupulous in ethics, but to go quite a bit further.

For example, whenever a junior faculty member is naive or inexperienced enough to offer to pay for lunch, NSF program officers will invariably explain, in a patient yet respectful manner, that they must never take money from their academic colleagues for lunch, for travel, for housing, or for anything else. Sometimes the program officer will cite the exact governing statutes, just to clarify the point. More recently I have interacted with representatives of the Obama administration’s Department of Education, and have found them to be exactly the same in this regard.

After I explained all this, my acquaintances finally acknowledged that this constituted more than “anecdotal” evidence. But they still did not budge on my larger point, which was that such successful models of uncorrupt governance could, with diligence, find their way into other parts of the government.

On this last point, my friends simply looked at me with a combination of pity and fondness. I think their fondness was in remembrance of a time in their lives when they too had been so naive and innocent. Before they had come to view all government, with the exception perhaps of a few oddly incongruous pockets of integrity here and there, as a seething pit of putrescent rot, a thing of horror and pestilence, the work of the very devil.

A way forward

Thursday, August 16th, 2012

Today I needed to put together two pieces of software, each of which had its own gnarly quirks and peculiarities. The task seemed daunting — I couldn’t see a way forward that would not immediately result in one or the other piece breaking.

So I created a little toy version of one of the two pieces of software — just a few lines of code pretending to be the real thing — and stuck it inside the other one. In this way I got a little of it to work, and then a little more, and then after that a little more still.

Finally, I was able to bring in the real code, since by now — by working with my little toy version — I had layered on the little tweaks and adjustments that made it play well with others.

I am reminded of the old days when bridges would be built by flying a kite across a river. Once the kite was on the other side, the bridge builders would use that string to pull across a slightly thicker string, and then use that string to pull across an even thicker string, and so on. Eventually there would be a strong rope across the river, and bridge building could begin in earnest.

Maybe there is some generalizable lesson here. When a task seems too formidable, start out by solving a manageable toy version of that task, and then gradually level up until you get to the real thing. Once you look at problems in this light, there is always a way forward.

Site-specific exorcism

Wednesday, August 15th, 2012

Have you ever gone back to a place that was strongly associated in your mind with a person you were once very close to — someone who is, for one reason or another, no longer in your life?

Such places can have the power to exert a ghostly pull. There was, perhaps, the conversation you had on this day, or the smile you shared on that. In random moments, a single location can transform into an entire telescoping almanac of events, a sudden onrush of phantom images from a world that is no more.

It can be nice on occasion to savor these images, painful edges and all. As a wise man once said, “Without a hurt the heart is hollow.” On the other hand, sometimes one wants simply to fling open the shutters — inviting the fresh air to pour in and our ghosts to flutter out.

There should be some sort of exorcism for these places in our lives. Even a minor spell would do, sufficient to provide a temporary respite. Perhaps an incantation or ritual, a lighting of candles and mumbling of words in some half forgotten tongue. Some way to be able to say, every now and again, “Today, at least today, this place is not ours, but mine alone.”

Sharpening the axe

Tuesday, August 14th, 2012

“Give me six hours to chop down a tree and I will spend the first four sharpening the axe.” — Abraham Lincoln

This summer I’ve been gradually pulling together various research software that I’ve built over the course of many years and many projects. The general idea is to create a single environment that easily allows anything to be used together with anything else.

So all of the procedural modeling and texturing tools, animation, A.I., user interface widgets, musical keyboard and midi access, exotic tracking devices, live coding editor, and so on, are gradually ending up in one place.

I’m hoping to get it all working smoothly together before the semester starts, as a platform that students can use to develop their own cool stuff. I’m sure the students will do a lot of cool things with it that I never would have thought of. :-)

Anagram

Monday, August 13th, 2012

As long as we are talking about presidential politics — and continuing on the general theme of word games — I was fascinated over this past weekend to see the U.S. presidential Republican ticket of “Romney” expand to become the ticket of “Romney and Ryan”.

That added part “and Ryan” is, of course, an anagram for “Ayn Rand”.

This is entirely consistent with the fact that Rand, the well-known Objectivist author and philosopher, has been a muse and moral guide for Paul Ryan for quite some time. He has made a point of quoting her ideas in various speeches as an underlying intellectual justification for his important and gallant proposal to provide economic relief for the top 1%.

Oh ok, actually, the top 0.01%, but let’s not quibble.

Unfortunately, as you may know, Rand recently betrayed Ryan’s faith in her — and by extension the faith of the top 0.01% — by revealing herself to be an atheist (atheism, for those of you who do not know, is in fact the antithesis of faith).

Remarkably, Rand figured out how to achieve this dastardly about-face after having been dead for over thirty years. Which just goes to show what a slippery character she is.

Manufactured cynicism

Sunday, August 12th, 2012

I’ve been watching the heating up of the political debate in this country around the coming presidential election, and I can’t help but notice that it’s been getting a bit weird. Everything is being framed in terms of “good guys” versus “bad guys”.

Of course, depending on whom you ask, the identities of those representing “good” or “evil” are mutable.

This is, of course, a classic media circus production. It reminds me a bit of the plot of the Charles Dickens novel “Bleak House”, which centers around a multigenerational fight over the family fortune. The result in the end is that nobody gets any money — except the lawyers.

In this case the winners are, arguably, not the lawyers, but the media industry. The more angry and cynical and divisive we all become, the more we are pushed to the reliance on polarizing sound bytes, rather than on our own abilities, as citizens, for reasoned debate.