This is a black and white photo, but an artist has drawn color lines through it | Hacker News Reader

This is a black and white photo, but an artist has drawn color lines through it

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92 pointsthunderbong28 comments

Curious that this effect is particularly pronounced for me on all but the "red" shirts.

Same here. They look completely grey, but the red stripes really stand out.

This is complete speculation, but the luminance difference between the red sprites and greyscale shirt is greater than that of the other colors.

I find the effect works best for the blue and not at all for red. I wonder if this could be related to chromostereopsis? It could be causing the red grid to appear superimposed above the grey rather than being filtered through it?

https://en.wikipedia.org/wiki/Chromostereopsis

TIL why some images I view through VR HMDs seem more 3d than they should be.

https://www.patreon.com/posts/color-grid-28734535

From the artist

this is honestly way cooler than the OP tweet

Great demonstration of why chroma subsampling works.

Exactly. The brain isn't "filling in" anything like the post claims -- we just have lower resolution for color than for brightness.

I didn't think my brain was filling anything. It just wasn't bothered.

These visual tricks are neat. There's one where by putting black strips in "strategic" places the person pictured looks naked. :)

See Josef Alber’s Interaction of Color for more information and studies of relative color. It’s a fascinating subject and color theory is very useful for UX and getting more bang with less colors. (https://yalebooks.yale.edu/book/9780300179354/interaction-of...)

I wonder if there is a good partial colloring technique for eink displays in this...

https://imgur.com/a/b7dIJa6

A tangential observation: the imgur site warns me that the image contains adult content when it clearly doesn't. I wonder if it is the girl at the bottom right of the image that's throwing the algorithm off.

Tineye.com found several older copies of this image posted to imgur (such as https://i.imgur.com/rIvpLcr.jpg and https://i.imgur.com/0Q7YnPvh.jpg) and yet, I'm not shown the adult content warning for those. Go figure.

I didn't believe it, but I screenshotted and checked in GIMP. It is.

Kind of funny because the creator of this is a major contributor to GIMP (assuming it's the same Øyvind Kolås).

Is this essentially a grid "mask" that lets the actual colors through on the grid lines? Or are the colors on the grid lines altered from the original color photo?

Looks to me like the later.

What I really want to know is, how closely are these perceived colours matching the actual scene.

For some reason I twice read that as saying "this is a black and white potato", once when seeing the headline here and once in the Twitter title, and my momentary confusion upon seeing that the "potato" somehow translated to a picture of girls holding a turtle... just because of some color lines, wtf?? Oops.

This is how you jpeg

Would this work on real t-shirts?

It's somewhat scale dependent. If you zoom in enough on the OP image you can make out the cross-hatching quite easily, but at preview scale (i.e. standing further away from someone wearing such a shirt) the illusion's OK.

(2019)

Wat r they trying to imply?

Our eyes aren't real

There is no limit to how much color you can add to a black and white photo. Really makes you think

its an interesting optical illusion. they;re trying to imply you should take a look at it for curiosities sake.

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