stuff by antimatter15

The rationale behind this is actually pretty contrived, but one of my friends had an imminent birthday, and I had no idea what kind of present to get her. Incidentally she sent had been working on some project and sent me a copy to look over- a request that I honored by perpetually promising to get to it eventually. Sure, it was interesting enough, but several months elapsed and I was beginning to face the fact that I would in all likelihood never actually get to it (kind of like my bottomless Instapaper queue from three years ago)- but that resounding guilt instilled the notion that somehow she liked astrophysics (the paper was something on Perlmutter’s Nobel). So in the absence of any other good ideas, I decided to get her a giant printout of the classic WMAP CMBR.

Soon after finding a poster for sale off Zazzle entitled the “Face of God“ (a particularly poetic pantheistic epithet), I found out that only a week earlier the European Space Agency had published the results of their Planck probe- a substantially higher quality rendition of the cosmic microwave background. So the solution would be simple, I’d just take that new, clearer image and upload it to that poster-printer under some clever title like “Face of God- Dove Real Beauty^TM“, as if the NASA’s WMAP is some kind of odd gaussian girl trope.

But the ESA’s Planck coloring is for some unfathomable reason particularly ugly. Sure it has a kind of crude appeal reminiscent of some kind of yellowed 14th century cartographic map with its tan speckled shades of color, but in general, it’s just kind of ugly. Maybe it’s five hundred million years of evolution that makes me particularly predisposed to the blue-green aesthetic of leafy flora and the azure sky. Also, for sake of recognizability, the WMAP data has made its fame with that particular coloring, it’s kind of unreasonable to expect someone to recognize it even after the color scheme has been changed.

The task of recoloring it was actually pretty simple, I just had to locate a legend for the respective graphs- a solid gradient which spans from the cool side to the warm side (the actual range of the data is only ±2mK so there isn’t in this case a massive difference between cool and warm). After crawling through a handful of scientific publications, it’s easy enough to find one and take a screenshot.

The difference in width is actually a kind of useless distinction, an artifact of the resolution of the paper or image I extracted the gradient from. It’s kind of interesting because I don’t really have any idea what the mathematical basis of these gradients are. The WMAP one looks like a simple rainbow so it may just be the colors arranged in progressively increasing wavelength, while the ESA coloring appears to be some kind of linear interpolation between red, white and blue (if the nationalities were inverted, one might be tempted to say murrica).

But once the gradient is established, it becomes the trivial task of mapping the colors of one image to another, something that I kind of hackedly accomplished with a Python script using PIL (It took a minute or so to process the 8 million pixels, but that’s not really too bad). And then, because the ultimate purpose of my project wasn’t so much to attain scientific accuracy as feigning it with some kind of better aesthetic, I went to GIMP and superimposed a translucent copy of the WMAP data so the image isn’t quite so speckled and the larger continental blobs more apparent.

Here is the poster if you want it. And the resulting 6.1MB jpeg.

Every once in a while some gadget has the misfortune of epitomizing the next first world problem. I guess right now, this is owning a Retina (or equivalent) laptop, tablet (arguably phone, but most web pages are scaled out so it’s not that big of a problem) and being irked at the prevalence of badly scaled graphics. So there’s a new buzzword “Retina Ready” for websites, layouts and designs which support higher resolution graphics for devices which support it, often meaning of lots of new files and new css rules. It’s this trend of high-pixel-density devices (with devices like the iPad 3, Retina Macbook Pro, Nexus 10 and Chromebook Pixel - though I for one don’t currently have any of them, just this old glitchy-albeit-functional first generation Chromebook) that is driving people to vector icon fonts.

But the problem of radical increases in terms of resolution isn’t a new one. Old arcade games rarely exceeded 260x315, and the Game Boy Color had a paltry 160x144. While a few people still nostalgically lug around game cabinets and dig out their dust-covered childhood handheld consoles for nostalgic sneezing fits, most of the old games are now played with emulators running on systems several orders of magnitude more sophisticated in every imaginable aspect. So that arcade monitor that once could engross a childhood (and maybe early manhood) now appears nothing more than a two inch square on a twenty inch monitor. But luckily there is a surprisingly good solution to all of this in the form of algorithms designed in particular for scaling pixel art.

The most basic form of image scaling that exists is called nearest-neighbor interpolation, which is extra simple for retina devices because it means simply growing the size of each pixel by a factor of two along each axis. That leads to things which are blocky, and unless you’re part of an 8-bit retro-art project with a chiptune soundtrack looks ugly.

The most common form of image scaling borrows a lot from the math and signal processing fields, with names like bilinear, bicubic, and lanzcos essentially they treat an image as some kind of composition of sinusoidal parts and try to ideally extrapolate and interpolate such that visible artifacts are marginalized. It’s all very mathy, but the result is kind of the opposite of nearest-neighbor because it has the tendency to make things blurry and fuzzy.

The thing is that the latter tries to reach some kind of mathematical ideal, because images taken by your friendly neighborhood DSLR-toting amateur (spider-powers optional) are actually samples of real world points of data— so this mathematical pursuit of purity works out very well. There’s still the factor-of-four information-theoretic gap that needs to be filled in with best-guesstimates, but there isn’t really any way to improve the way a photograph is scaled without using a higher-resolution version of said photograph. But most photographs that are taken already are sixteen-megapixel monsters and they usually still look acceptable when upscaled.

The problem arises with pixel art, little icons or buttons which someone painstakingly drew in Photoshop one lazy summer afternoon in the late 90s. They’re everywhere and each pixel isn’t captured and encoded by a sampling algorithm of some analog natural phenomona— each pixel was lovingly crafted and planted by some meticulous artist. There is no underlying analog signal to interpret, it’s a direct perceptual hookup to the mind of the creator— and that’s why bicubic sampling looks especially bad here.

Video games, before 3d graphics engines and math-aware anti-aliasing concerned with murdering jaggies, in the old civilized age of bit-blitting, were mostly constructed out of pixel art. Each color in that limited palette was placed there for a reason and could be exploited by specialized algorithms to construct higher-quality upscaled versions which remained sharp. These come with the names EPX, Scale2x, AdvMAME2x, Eagle, 2×Sal, Super 2×Sal, hqx, and most recently, Kopf-Lischinksi. These algorithms could be applied in real time to emulator windows to acceptably scale a game to new sizes while eschewing jagged corners and blurry edges.

Anyway the cool thing is that you can probably apply these algorithms in lieu of the nearest-neighbor or bilinear scaling algorithms used by browsers on retina platforms to effortlessly upgrade old sites to shiny and smooth. With a few rough heuristics (detect if an image appears to be a sprite by testing for a limited palette, see if the image is small or a perfect square, detect if it has transparent pixels) this could be packed into a simple script include that website makers could easily inject into their pages to automagically upconvert old graphics to new shiny high-resolution ones without having to go through the actual effort of drawing new high resolution graphics and uploading them online. And this could also be packaged as a browser extension so that, once and forever after, this first-world nuisance shall be no more.

Before setting out to port hqx-java to javascript, I actually did some cursory googling to see if it actually had been done before. Midway through writing this post, I found out that it actually had been done before, in a better way, so I won’t even bother linking to my inferior version. But either way the actual goal of this project was the part which was detailed in the last paragraph, that of an embeddable script or browser extension which could heuristically apply pixel-scaling algorithms— something I probably won’t bother trying to do until at least after I get my college laptop (which I anticipate will be a Retina Macbook Pro 15”). Nonetheless, I haven’t written an actual blog post in almost three months and it’s the last day of this month, and I guess it’s better than having you all (though nobody’s probably going to read this now that Google Reader has died) assume that I’ve died. Anyway, now I’m probably going to retroactively publish old blog posts in previous months to fraud continuity.

Swipe2

I’ve actually had this post fermenting in my blog’s draft folder since at least September, but I never actually got around to finishing the post. And now that Google’s enabling the new swipe-to-go-back by default on the dev channel versions of Chrome OS, it finally feels like the right time to post. As in, I feel like posting things right when they’re soon to be absolutely useless (Which, you might recall, was the case with my Google Wave client, which started selling on the App Store the day Google announced that Wave would be phased out and eventually shut down).

So, a few months ago, I finished my update to the Swipe Gesture extension, which featured a rather significant redesign. It supported multiple gesture directions and a fancy animated element to indicate the direction of the gesture.

On December 15th, 2012 12:15pm, I was accepted Early Action to the Massachusetts Institute of Technology, so I’ll be there starting this fall :)

This blog isn’t principally here to boost my ego, so I’ll leave it at that, because I’m writing this post some six months after-the-fact with a fake retroactive timestamp in order to fraud my monthly post-count goal.

Okay, so I really want to maintain at least one blog post per month, and here I am, right before New Year’s with no apocalypse in sight to rapture me away from having to write a blog post. I don’t have anything particularly interesting ready to share, so here’s something fun that only took a few hours.

The rather long Bayeux tapestry of an image I have crammed to the right marks the culmination of a series of rather odd tangents. It also serves as a reminder for me to abandon hope#Overview_and_vestibule_of_Hell), because the shape of the conversation forces whatever post I plan on writing to be verbose enough as to fill all that vertical space so that the actual text here isn’t dwarfed by the image, which would be aesthetically jarring.

It all started the day before yesterday (I’m pretty sure it wasn’t actually then, but this is my abridged timeline and I’m entitled to indulge in whatever revisionist temptations I have as I’m writing this at a rather late hour, because 2013 is creeping closer at an uncomfortably fast rate and I still have some finite quantity of homework I haven’t attempted to start over the course of the past week), when my friend Robert realized that a rather significant portion of my chat responses include “wat”, “walp”, “lol”, “yeah”, “:P”, “cool”. From that, he logically sought to create a naive bayes predictor of me, because, why have a person nod in consent, when you can have a robot which can, to some degree of accuracy, automatically give that nod of assent without bothering a physical human being.

This isn’t quite the same thing as a traditional chat bot, because traditional chat bots don’t pretend to be actual people, largely because the state-of-the-art of artificial intelligence is quite a ways off from creating something which can suitably pass a Turing test, and even further away from being able to learn the entire knowledge of a person and provide an intelligent response to every imaginable stimulus. A closer approximation would be that this is a sort of semi-automated chat-macro system, whereby my generally useless responses of agreement are outsourced to a rudimentary script, fully capable of replicating my own rather unhelpful self. And from that it’s able to try to behave human by replicating a very very narrow subset of activity, deferring to a real human transparently.

It’s somewhat like how GMail has a priority inbox feature which uses magical algorithms to separate the wheat from the chaff, diverting your attention away from the less subjectively important emails toward the few which actually matter. Except instead of giving the user ultimate discretion over the emails, this one would simply reply with “lol”.

It’s pretty easy to see any realistic application of this as rare. But I could totally be wrong, and I could be seeing this from totally the wrong angle. It’s entirely plausible that some subtle variant of this idea is absolutely brilliant, and will serve as the future of networked communication for decades to come. Maybe as email evolves the way of the Dodo, Instant Messaging will become the semi-permanent high-persistence low-immediacy ironic-initialism that takes email’s place, and the rest of the world becomes burn-on-reading SnapChats. Maybe SnapChat gets combined with lifelogging, and every minute of your life gets divided into four second snippets, and sent to one of your four thousand middle-school friends, so they can bask in the new hyper-intimate super-network, fueled by non-discretionary artificial intelligence filters.

That was Robert’s end anyway. He went on combing through our accumulated ~30,000 messages with his handy Mathematica trying to identify pertinent features which might probably replace me. On my side of the thing, I started with the userscript which would run on my browser to intercept the messages he sent, process them, and to send out a response, if a suitable automated one existed.

This actually turned out to be slightly more difficult than I had anticipated, for a single reason, and it was and has been the same reason that has bothered me for quite some time. Firing events. I really probably should learn how to use Selenium or something to automate things in a nice and clean way.

And that’s completely ignoring the five hundred pound trivial solution in the room, which isn’t to use a 500lb gorilla as a metaphor. Facebook supports XMPP which is a nice open source protocol with a billion implementations and it’s really not that hard to automate. I mean I’ve even done it before. I have a Raspberry Pi after all, and I can use it to run useless services like this, because I’ve decided that that’s exactly what a Raspberry Pi is for. But I didn’t and I have no idea why. C’est la vie, I guess.

The secret ended up being to Google a bunch of phrases related to keyboard-event-emitting with initializeKeyboardEvent or something of that sort a lot of times and stealing some code from StackOverflow. It took a few tries, but eventually something that worked emerged, and it was cool.

For posterity, this was the code that worked:

But that wasn’t the end of it. No, now there was a piece of code which could convincingly send a message, but it also had to read messages too. That wasn’t hard, actually, I just created a MutationObserver object and named it after a Fringe character. But then, presumably because Robert’s code was still training on that 30k message corpus, or something inexplicable, I built a crappy rudimentary thing with four or so simple regular expression based rules.

One of them happened to be that if someone were to send me the message “lol”, I would inexplicably respond as well with “lol”. This wasn’t initially a problem because the idea was to create a robotic version of me and _only _me. But Robert found it cool too so he ran the same script. Problem was, that this meant that if either one of us were to introduce the word “lol”, it would spiral nigh perpetually ad nauseam.

Somehow this sparked the idea to implement simple esoteric languages on it. The first one was a simple substitution rule. 0 -> 1, 1 -> 10. And over a few iterations it grew and took up huge amounts of space.

Next up was implementing a tag system. I implemented the 2-tag collatz sequence one. The cool thing is that it’s actually insanely easy to implement. You just take a sequence of symbols, strip the first two, and append the first symbol after you’ve transformed it according to a certain transformation mapping.

It was interesting as each little computation of this tiny esolang of a chat conversation involved a round trip of hundreds of miles. But each tag was still letters, ‘a’, ‘b’, and ‘c’. And it was getting late, and I thought that maybe it would be nice to hark back at inside-joke/theory of sorts that sparked it all. So I decided that our tags could be, instead of solitary letters, comprise word symbols like “lol”, “d:” and “wat”, which perhaps is a subconscious reference to an old webcomic that I had posted a while ago about a steganographic system built on internet vernacular.

I updated my script, posted it to him, he ran it, and initiated it all by saying “lol lol lol”. And from then the line lengths grew and shrank like mountainous terrain, eventually converging on the final state, a solitary “lol”. And for some inexplicable reason, some weird quirk of fate, or some deeper underlying truth to the universe, Robert always got the last “lol”. When I had tried it with a random initiating code, it would always terminate in some odd number of iterations, leaving me with the lowly penultimate laugh.

It sort of broke after that, and we didn’t fix it.

Nonetheless, there’s something incredibly cool about how an idea for something questionably turing-test-worthy can evolve into something turing-complete.

And that’s a basic summary of how uneventful my winter break has been, incidentally written with exactly 1337 words.