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How and why to take a logarithm of an image [video]

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Re: How and why to take a logarithm of an image [video]

#21

Post by pdpi »

Jeff_Brown wrote: post #7

I love 3B1B but generally don't have time to watch long videos. Can anyone sum up the punchline?

The punchline is that you can fill in the centre of Escher's piece by using complex analysis, and it produces a very satisfying, "obviously correct", solution.

But, as with all jokes, the punchline isn't funny at all without the setup.

Re: How and why to take a logarithm of an image [video]

#22

Post by Modified3019 »

m-hodges wrote: post #11
peesem wrote: post #10

Earlier quoted context omitted.

YouTube has A/B testing features that allow videos to have multiple titles and/or thumbnails.

Right. So I thought it would be helpful to share the more-descriptive title that I got.

This is what I use DeArrow for, crowdsourced titles and thumbnails (from the maker of SponsorBlock): https://github.com/ajayyy/DeArrow

Re: How and why to take a logarithm of an image [video]

#23

Post by rcxdude »

ahns wrote: post #13
Jeff_Brown wrote: post #7

I love 3B1B but generally don't have time to watch long videos. Can anyone sum up the punchline?

One of Dutch artist M.C. Escher's works is a man is admiring a piece of art that itself depicts the building the (very same) man is in [0]. Escher left out the middle bit of the painting, probably since it's fairly complicated, putting his signature there instead. The video itself is about the complex analysis used to fill in that missing middle, based on a paper ~20 years ago. [0] https://en.wikipedia.org/wiki/Print…

I think the gap also has a compositional purpose: the viewer's eye is meant to travel around the image in a circle, and the gap helps anchor that in a way that the filled-in version might not.

Re: How and why to take a logarithm of an image [video]

#24

Post by rcxdude »

Jeff_Brown wrote: post #7

I love 3B1B but generally don't have time to watch long videos. Can anyone sum up the punchline?

The image is essentially a self-similar 'droste-effect' image in disguise. The warping of that image shifts that self- similarity into a visual loop, but the warped image still has a droste-style self-similarity in the center as well.

Re: How and why to take a logarithm of an image [video]

#25

Post by rcxdude »

hnuser123456 wrote: post #8
coldpie wrote: post #4

Clickbait title could use another pass. What is this about?

It's about examining the mathematical methods MC Escher used in one of his recursive drawings.

Probably he didn't use these techniques explicity: the video mentions but doesn't emphasise that he probably sketched out the map by feel instead of analytically, which is probably one reason why he didn't fill in the center.

Re: How and why to take a logarithm of an image [video]

#26

Post by dandanua »

peesem wrote: post #10
m-hodges wrote: post #6

The title I get when I click on this is, "How (and why) to take a logarithm of an image"

YouTube has A/B testing features that allow videos to have multiple titles and/or thumbnails.

I'm sorry, what? Can people now see different titles? Insanity, if true.

Re: How and why to take a logarithm of an image [video]

#27

Post by jgwil2 »

coldpie wrote: post #4

Clickbait title could use another pass. What is this about?

This was the title used when I came across the video. Apparently YouTube uses many different titles for A/B testing but this is the one I got. Can't edit it now, unfortunately.

EDIT: seems like dang or team took care of it, thanks!

Re: How and why to take a logarithm of an image [video]

#28

Post by JKCalhoun »

boriskourt wrote: post #2

This video is an absolute tour de force of communicating a complex concept.

Seems like you could apply the clever transforms to generate a displacement map (that then allows you to move it across any source image and quickly get the Droste effect).

(I still have not made it all the way to the end of the video though, perhaps that is where they end up.)

Re: How and why to take a logarithm of an image [video]

#30

Post by manudaro »

I've been loking into how 3B1B builds their rendering pipeline, and it's honestly mind blowing. They use Python along with custom OpenGl shaders to handle most of geometric transformations, shich seems to be what creates those "brain breaking" visual effects.It's fascinating how our visual cortex tries to interpret overlapping geometric patterns and ends up producing such counterintuitive perceptions. Shat I still can't quite wrap my hand around is... to what extent are these effects caused by the rendering itself, and how much of it is just how our brain interprets the visual information?
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