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

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?

an hour agomanudaro

there is at least one video, if not a series of videos, where he explains his process in detail, showing the coding process and everything. it is a collaboration with another person where, if i recall, he is teaching them.

i will see if i can find it.

edit: "How I animate 3Blue1Brown | A Manim demo with Ben Sparks" https://www.youtube.com/watch?v=rbu7Zu5X1zI

more on workflow: https://github.com/3b1b/videos?tab=readme-ov-file#workflow

code for videos: https://github.com/3b1b/videos

manim: https://github.com/3b1b/manim

manim community edition: https://github.com/ManimCommunity/manim/

an hour agojohn_strinlai
[deleted]
an hour ago

Makes me wonder how this would look/feel interactively if a game world was rendered like this

7 minutes agoqoez

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

3 hours agoboriskourt

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.)

2 hours agoJKCalhoun

All of 3Blue1Brown is - hoghly highly recommend

3 hours agodmbche

I've seen most! Highlighting this one out of them all. Exemplary! : D

2 hours agoboriskourt

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

3 hours agom-hodges

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

3 hours agopeesem

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

3 hours agom-hodges

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

2 hours agodandanua

It has been that way for a while now. I see Veritasium video titles and thumbnails change quite often, it can be quite annoying as it sometimes gives the appearance of it being a whole new video.

A/B testing a title feels wrong to me, its almost as bad as A/B testing a UUID. Just pick a title and stick to it unless you need to fix a factual error.

an hour agohidroto

Titles and thumbnails have a huge impact on video performance, and when it's your main income it seems reasonable to try to marginalise the impact.

an hour agozacmps

For me it is "Decoding Escher's most mind-bending piece"

3 hours agosva_

> How (and why) to take a logarithm of an image

I watched it a few days ago and this descriptive title was part of the reason I clicked. I generally trust 3B1B anyway but normally a title like "This picture broke my brain" would put me off.

an hour agoclose04

In case you're curious, when I ran that title/thumbnail AB test, the option "This picture broke my brain" did end up winning. I was a bit disappointed, because I didn't really _want_ it to win, but I did include it out of curiosity. Ultimately, I changed it to the other title, mostly because I like it better, and the margin was small.

I was genuinely torn about how to title this, because one of my aims is that it stands to be enjoyed by people outside the usual online-math-viewing circles, especially the first 12 minutes, and leaning into the idea of a complex log risks alienating some of those.

an hour ago3b1b

perhaps a bit inappropriate of me to say so here as it is off-topic, but i am going to take the opportunity anyways:

big thanks for all of your work making math both enjoyable and accessible. my kids (and i) love your videos. your positive impact extends far and wide.

13 minutes agojohn_strinlai

That makes me wonder: do you see a difference in when viewers drop off between using a more math-y title versus a more accessible one?

The "broke my brain" title originally put me off from watching. I caved after a few days; I think the video is one of your best!

30 minutes agocromulent2

i see "Decoding Escher's most mind-bending piece".

fascinating, and absurdly confusing, that there are multiple titles.

an hour agojohn_strinlai

This kind of technique can be used in 3D space as well! The analysis here represents Escher's techniques as conformal maps in the complex plane. Conformal maps are also possible, though more limited, in R^3. This is something that I explored some years ago and wrote an article about it, though it focuses more graphics than math: https://www.osar.fr/notes/logspherical/

43 minutes agopierrec

I've been wondering if you could do a similar thing for a Droste effect image containing two copies of itself. Packs of Laughing Cow cheese show a cow with two earrings, each of which is a pack of the cheese.

2 hours agoOscarCunningham

Clickbait title broke my brain.

3 hours agoamelius

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

3 hours agoJeff_Brown

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_Gallery_(M._C._Escher)

3 hours agoahns

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.

2 hours agorcxdude

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.

2 hours agopdpi

The print gallery is just Aw^c in the complex plane

2 hours agoyread

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.

2 hours agorcxdude

Awᶜ

This kind of risks obscuring what's actually going on.

an hour agoLerc

The whole point is the explanation... it's a bit like someone telling you to take a 2 week holidays somewhere and you'd just say: it's too long, can't someone just get me a plane ticket there and back the same day so I can compress the stay?

2 hours agooulipo2

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

3 hours agocoldpie

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!

2 hours agojgwil2

It makes more sense when seen on YouTube where you get the thumbnail of one of M. C. Eschers famous drawings is shown.

It’s a drawing of a guy looking at a picture of a town with himself standing in the town, but it’s all twirled and twisted so it’s self repetition isn’t obvious.

3 hours agowodenokoto

I clicked on the link and the video title is "Decoding Escher's most mind-bending piece", which is a lot better. I also had no idea what "3B1B video" meant, apparently it's a channel called "3Blue1Brown".

3 hours agonticompass

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

3 hours agohnuser123456

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.

2 hours agorcxdude

> Examining the mathematical methods MC Escher used in one of his recursive drawings

This would be an excellent title :)

3 hours agocoldpie

Depends how you define excellent. If the goal is to get more views then it's not all that great, and views are kind of the point of YouTube for many, especially if they are trying to make a living from it.

3 hours agoSirMaster

That's great for YouTube, but HN has some guidelines:

> please use the original title, unless it is misleading or linkbait