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Edge detection doesn’t explain line drawing

aaronhertzmann.com

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Re: Edge detection doesn’t explain line drawing

#101

Post by wpietri »

hprotagonist wrote: post #8
cnity wrote: post #3

As someone (probably like many here) who graduated from a university which taught computer vision and peripheral neuroscience courses, with such titles as "Computational Neuroscience of Vision", I always felt that trying to understand the human brain as a kind of algorithm was a bit of an artefact of computer scientists as they approach biology. The truth is the visual cortex is vast, and not sufficient to explain th…

ah, someone who paid attention in lecture! (incidentally; there’s a fairly deep literature of historians of science that have carefully documented that we describe ourselves as analogous to the most sophisticated technology of the day: see “to lose one’s temper”, “to blow a gasket”, “i got my wires crossed”, “sorry, cache miss”, … as metaphors and idioms of mental state through the centuries that reflect the cool tec…

Ooh, that's very interesting. How would I find the metaphors used before, say, the industrial revolution?

Re: Edge detection doesn’t explain line drawing

#102

Post by mahathu »

ben_w wrote: post #23
hprotagonist wrote: post #8

Earlier quoted context omitted.

ah, someone who paid attention in lecture! (incidentally; there’s a fairly deep literature of historians of science that have carefully documented that we describe ourselves as analogous to the most sophisticated technology of the day: see “to lose one’s temper”, “to blow a gasket”, “i got my wires crossed”, “sorry, cache miss”, … as metaphors and idioms of mental state through the centuries that reflect the cool tec…

> to lose one’s temper Huh, never thought about that one before. Linguistic stuff like this is fun to find; these days I mostly spot it via learning German as a second language, so the artifice in artificial intelligence becomes “Künstliches Intelligenz” where “Kunst” is artist and “Kunststoff” is plastic, and in Middle Low German “kunst” is knowledge and ability. > coined Deliberate choice to exemplify your point, o…

> where “Kunst” is artist and “Kunststoff” is plastic, and in Middle Low German “kunst” is knowledge and ability.

Kunst means art, and an artist is a "Künstler" in German. (and Intelligenz is grammatically female, so there is no trailing s in "künstlich" in "künstliche Intelligenz". Its a difficult language.

Re: Edge detection doesn’t explain line drawing

#103

Post by pegasus »

lostlogin wrote: post #70
mjburgess wrote: post #42

Earlier quoted context omitted.

Reasoning by analogy is one of the ways we solve the framing problem. So, when explaining the universe we imagine it's an act of will by a conscious entity (ie., like how we invent). When explaining the mind we suppose it's like one of our inventions. Absent an analogy of some kind it's quite hard to determine what features are salient. Objects have an essentially infinite number of properties.

> So, when explaining the universe we imagine it's an act of will by a conscious entity Unless I’m misunderstand you, that line of reasoning assumes one is religious.

Not necessarily, see for example Nick Bostrom's Simulation Hypothesis.

Maybe one could argue that too requires adherence to some religious dogma (Scientism? Reductionism?)

Re: Edge detection doesn’t explain line drawing

#104

Post by colechristensen »

cnity wrote: post #3

As someone (probably like many here) who graduated from a university which taught computer vision and peripheral neuroscience courses, with such titles as "Computational Neuroscience of Vision", I always felt that trying to understand the human brain as a kind of algorithm was a bit of an artefact of computer scientists as they approach biology. The truth is the visual cortex is vast, and not sufficient to explain th…

>The truth is the visual cortex is vast, and not sufficient to explain the human classification and perception of objects visually.

There have been experiments which have exactly located individual neurons and sets of neurons responsible for the first layers of image recognition. i.e. a neuron that fires when a specific spot on a retina is stimulated (a single pixel) and neurons that fire which detect lines. This is not theoretical but actual probing of living brains. I'll find the paper(s) later.

Re: Edge detection doesn’t explain line drawing

#105

Post by strogonoff »

simias wrote: post #86
JoeAltmaier wrote: post #13

Earlier quoted context omitted.

The difference between the data in the image, and the information? If for instance you upscaled text so large that it became blurry and unrecognizable, you lost information. Our cortext is all about interpreting what we see. Almost before our brain proper has the data, nerves have begun extracting information (edges etc). Probably because it was the difference between hitting and missing the animal with the spear. Or…

Precisely! I also find it interesting how, from an information theory standpoint, audio processing and image processing are effectively the same thing (audio resampling is fundamentally 1D image scaling for instance) but because humans process sounds very differently from images we end up doing things pretty differently. For instance when we want to subjectively make images more attractive we tend increase contrast a…

The old habit of reaching to “increase contrast”[0] as a means of making an image more attractive exists in large part because 1) the dynamic range of modern display media is so tiny compared to the dynamic range of camera sensors and our eyes[1], and 2) the images most people typically work with are often recorded in that same tiny dynamic range.

If you work with raw photography, you will find that, as with audio, the dynamic range is substantially wider than the comfortable range of the available media: your job is, in fact, to compress that range into the tiny display space while strategically attenuating and accentuating various components—just like with raw audio, much more goes into it than merely compression, but fundamentally the approaches are much alike.

[0] Which actually does much more than that—the process is far from simply making the high values higher and low values lower.

[1] Though “dynamic range” is much less of a useful concept when applied to eyes—as with sound, we perceive light in temporal context.

Re: Edge detection doesn’t explain line drawing

#106

Post by furyofantares »

6D794163636F756 wrote: post #96
arketyp wrote: post #93

Earlier quoted context omitted.

The author comes across as ignorant at best, but then to present his own work as the Realism Hypothesis of Hertzmann, it leans more towards arrogance.

There is a subset of the tech bro that believes everything can be reduced to a problem with clearly defined taxonomy and as such every problem can be solved by an engineer with no subject knowledge. This article very much reads like one of those people wrote it.

I would be interested in your clearly defined taxonomy of tech bros.

Re: Edge detection doesn’t explain line drawing

#107

Post by nestorD »

simias wrote: post #9

Ten years or so ago I was working on a video chip that had an upscaler feature. While prototyping and simulating it, we first started by applying a mathematically-correct (i.e. information preserving) FIR filter to do the upscale. Then we compared the result with other solutions and found that ours looked worse. We asked our colleagues to blind-test it and they all picked third-party-scaled images over ours. At first…

A lot of smart TVs do that. Being able to spot it (played a lot with edge detection when discovering computer vision) is a curse.

Re: Edge detection doesn’t explain line drawing

#108

Post by phkahler »

wpietri wrote: post #100
6D794163636F756 wrote: post #96

Earlier quoted context omitted.

There is a subset of the tech bro that believes everything can be reduced to a problem with clearly defined taxonomy and as such every problem can be solved by an engineer with no subject knowledge. This article very much reads like one of those people wrote it.

Yeah, I have been guilty of that myself sometimes. This XKCD is a reminder to me: https://xkcd.com/793/

A manager once told me he'd never hire a PhD because once they complete the specialized work we hire them for, they inevitably get put on something outside their specialty - like your linked xkcd - and then their acceptance as experts along with that behavior causes real problems.

Another time I had an older PhD moved to my area (outside his) where we were trying to meet a number of objectives. He said in a meeting that "it is mathematicaly impossible" to achieve one of our performance goals. I quietly went back to the lab and ran my new control algorithm and documented hitting that goal. Never refuted him, just filed the incident away in my head.

Re: Edge detection doesn’t explain line drawing

#109

Post by kian »

milesvp wrote: post #87
detourdog wrote: post #62

Earlier quoted context omitted.

I believe the universe we live right now is no different than a simulation. Subtle difference in belief but I think it might have a big implication.

There is one key difference between reality and simulation. In reality you have to spend energy to remove noise. In simulation you have to spend energy to add noise. Or perhaps more accurately, all objects interact in reality and energy needs to be spent to prevent interaction, while simulation requires energy to make objects interact. But it’s even worse than it sounds at first, because you need to spend energy not…

This is an incredibly deep observation that essentially points to the problem with the representations we use to understand the Universe. It feels like the universe is essentially showing us that there is a non-supra-linear representation it uses (based on the kinds or fields of interactions?), and that calculating within this representation (between fields?) is somehow equivalent to calculating all of the interactions for the objects across all of the fields simultaneously.

Almost feels like it's related to P=NP or logic and meta-logic. Is it fundamentally impossible to use the same 'Universe'-al representation inside the Universe, a Gödel-like result limiting us only to the real? Or can we represent and run subsets of smaller universes within without a computational explosion? If so, does it eventually revert back to becoming fundamentally impossible at some limit, and if so, are we there yet? Can we measure how far from the limit we are, somehow?

Fun questions. Thanks for the provocative clarification.

Re: Edge detection doesn’t explain line drawing

#110

Post by dylan604 »

Earw0rm wrote: post #61
dylan604 wrote: post #55

Earlier quoted context omitted.

>as metaphors and idioms of mental state through the centuries after listing a bunch of things from the previous century that barely stretches a bit further back. i would have been impressed if you had come up with a phrase from medieval tech, or roman/greek/egyptian. hell, i'd settle for pioneer days tech to allow for "centuries". otherwise, it just feels like modern day analogies.

He's an open book? I needed to let off some steam?

I was thinking something more like "tied up in knots" or "wolf in sheep's clothing". Things before 1800s relevancy. Open book might be a little older, but surely, there were phrases older than that
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