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How and why to take a logarithm of an image [video]
- boriskourt 6mo agoThis video is an absolute tour de force of communicating a complex concept.
- dmbche 6mo agoAll of 3Blue1Brown is - hoghly highly recommend
- boriskourt 6mo agoI've seen most! Highlighting this one out of them all. Exemplary! : D
- JKCalhoun 6mo agoSeems 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.)
- Dwedit 6mo ago"Complex concept" I see what you did there.
- coldpie 6mo agoClickbait title could use another pass. What is this about?
- nticompass 6mo agoI 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".
- hnuser123456 6mo agoIt's about examining the mathematical methods MC Escher used in one of his recursive drawings.
- coldpie 6mo ago> Examining the mathematical methods MC Escher used in one of his recursive drawings This would be an excellent title :)
- SirMaster 6mo agoDepends 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.
- c-hendricks 6mo agoThat's great for YouTube, but HN has some guidelines: > please use the original title, unless it is misleading or linkbait
- rcxdude 6mo agoProbably 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.
- wodenokoto 6mo agoIt 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.
- jgwil2 6mo agoThis 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!
- m-hodges 6mo agoThe title I get when I click on this is, "How (and why) to take a logarithm of an image"
- peesem 6mo agoYouTube has A/B testing features that allow videos to have multiple titles and/or thumbnails.
- m-hodges 6mo agoRight. So I thought it would be helpful to share the more-descriptive title that I got.
- Modified3019 6mo agoThis is what I use DeArrow for, crowdsourced titles and thumbnails (from the maker of SponsorBlock): https://github.com/ajayyy/DeArrow https://github.com/ajayyy/DeArrow
- dandanua 6mo agoI'm sorry, what? Can people now see different titles? Insanity, if true.
- hidroto 6mo agoIt 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.
- zacmps 6mo agoTitles 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.
- Jeff_Brown 6mo agoI love 3B1B but generally don't have time to watch long videos. Can anyone sum up the punchline?
- ahns 6mo agoOne 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) https://en.wikipedia.org/wiki/Print_Gallery_(M._C._Escher)
- rcxdude 6mo agoI 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.
- ahns 6mo agoHm, since I can't edit my comment: link to paper [0] [0] https://pub.math.leidenuniv.nl/~smitbde/papers/2003-de_smit-lenstra-escher.pdf https://pub.math.leidenuniv.nl/~smitbde/papers/2003-de_smit-...
- daedrdev 6mo agoHN only allows editing comments for a short time
- oulipo2 6mo agoThe 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?
- yread 6mo ago
- amelius 6mo agoClickbait title broke my brain.
- OscarCunningham 6mo agoI'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.
- gowld 6mo agoWhat "similar thing" are you asking for? The Laughing Cow image exists. The Print Gallery is an object itself existing at 2 zoom levels in the same place, but the cheese exists in different places. You can't have two copies of the same image in the same place - that's not a copy; it's just itself.
- manudaro 6mo agoI'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?
- john_strinlai 6mo agothere 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 https://www.youtube.com/watch?v=rbu7Zu5X1zI more on workflow: https://github.com/3b1b/videos?tab=readme-ov-file#workflow https://github.com/3b1b/videos?tab=readme-ov-file#workflow code for videos: https://github.com/3b1b/videos https://github.com/3b1b/videos manim: https://github.com/3b1b/manim https://github.com/3b1b/manim manim community edition: https://github.com/ManimCommunity/manim/ https://github.com/ManimCommunity/manim/
- deleted 6mo ago[deleted]
- manudaro 6mo agoThis is great, thanks for digging these up. The workflow doc on Github is exactly what I wat looking for - didn't realize they had that level of documentation publicly available.
- pierrec 6mo agoThis 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 on graphics than math: https://www.osar.fr/notes/logspherical/ https://www.osar.fr/notes/logspherical/
- toxik 6mo agoSo to do this same Droste effect in 3D you would need a self-similar volume? Though since we can't really see 3D, we could never have that "one circle zooms in" effect. Or could you walk around in such a world? That would be a very cool concept for a game.
- pierrec 6mo agoThough since we can't really see 3D, we could never have that "one circle zooms in" effect. Well, the 3D structure just needs to be sufficiently "holey" for the effect to become apparent. For example a cage-like structure, or a house with no roof (when seen from above).
- qoez 6mo agoMakes me wonder how this would look/feel interactively if a game world was rendered like this
- marginalia_nu 6mo agoManifold Garden isn't far off.
- aprentic 6mo agoThose videos are awesome! 3B1Bs visualizations finally made e^(pi*i) make sense. His videos on Euler's formula inspired me to make a silly toy so I could play with it myself. https://gitlab.com/aprentic/complex-viz/ https://gitlab.com/aprentic/complex-viz/
- rappatic 6mo agoSimilarly, it's possible to take the derivative of a song. You can use a Fourier transform to express the song's waveform as a series of sin and cosine functions, then take the derivative. Imagine, for the sake of simplicity, you could express the song's waveform with the function 13 * sin(41x). The derivative of this function is 533 * cos(41x). Cosine, of course, is just a phase shifted sine, and the constant coefficient inside the function stays the same. So you're not changing anything about the shape of the wave, just stretching it vertically. This has the effect of mimicking a "high pass filter," amplifying the volume of the highs.
- toxik 6mo agoWell, you get the frequency domain derivative. This is the same as scaling the time domain by a linear ramp. Not exactly hugely useful, unless you happen to be in radar. You can take the finite difference with eg np.diff(waveform) though.
- toxik 6mo agoSo in other words you can take any Droste image and make an Escher zooming spiral effect. Neat. Also curious what happens if you take Escher's painting and undo the effect. Probably not great since it wasn't in the video. What a cool video.