Lenna

I think this photo has finally been retired in favor of other ones
- Well, since the lady herself has expressed a desire to end its use for that purpose, I consider that a good thing on top of the practical reasons.
  Not that I really know a damn thing about it beyond what I found in the linked article, but still
  
  Yeah there's like a whole documentary about this on YouTube. They even interview this person.
  It was really fascinating but as noted in the Wikipedia article it's not really accepted in any modern publication nowadays so it's all been but retired
- Yes (https://mortenhannemose.github.io/lena/)
  
  Honestly one of the best Replacements I've seen yet

The controversy around this image always felt to me like a case of information hazard.
Unless the subject of the image themselves had a problem with the usage (which they didn’t until recently), it should not have mattered.
The controversy began only after when the background/context around the image got established.
Having said that, I am aware the image has been used for decades in academic settings (it was in my university textbooks). But the resistance in moving to a different image was quite surprising. It was more surprising when I learnt journals and some pockets of academia had to impose a ban on the image since people (unknowingly, I hope) kept using the image even after the controversy erupted.
- I don't have a problem with the usage of the image on moral or social grounds, but I don't think that it's the best choice to use.
  In the past, Playboy has been fine with its use. I see no reason to believe that that will change. However, the image is not in the public domain: Playboy just decided to ignore infringement on goodwill grounds. I think that it'd probably be better to use an image that avoids the whole issue.
  Lenna asked that it stop being used recently. I don't believe that she has legal ownership of the image, but point is that use of the thing basically existed on goodwill grounds, and I don't think that changing that is a good idea. No reason to hurt someone's feelings when there are plenty of other options.
  While it may have good characteristics as photographs go, I seriously doubt that it's the best option out there; it wasn't as if it was selected after some extensive search.
  The test image is not terribly high resolution, at 512x512. While maybe that was fine for computers in the 1970s when it was chosen, it's not a whole lot of data.
  The image is a scan, has artifacts from the printing and scanning process. While arguably it could be useful to measure how scanned images work, I think that most images today are not scanned, but are direct-to-digital, and are probably more-useful.
  While I don't think that it's generally an issue in the West, some countries --- think the theocracy in Iran --- do take issue with bare shoulders, and it's just liable to create unnecessary problems for any people working on image compression there. Unless there's a good reason not to do so, might as well take a least-common denominator image.
  I think that the story is cute, and it's nice that Playboy decided to let people use it, but it's not as if the people who chose it were trying to choose a test image for the world.
  I think that the only case where it really makes sense to use the thing today would be to compare compression against some compression algorithm for which access to the algorithm no longer exists, but Lena compression test results exist, which seems unlikely to be much more than a niche case.

The image has attracted controversy in recent years because of its subject matter, and many journals have deemed it inappropriate and discouraged its use, while others have banned it from publication outright.
Brother, it's a cropped image. Who the fuck cares where it's from? What are we upset about here, a bare naked shoulder? That's some Victorian era level puritanism.
- The context of a bare naked shoulder is important. If you walked into a male CEOs office and he had a picture on his disk of his wife and his kids in swimsuits at the beach, you would probably feel differently about it than if he had a pin-up poster of a supermodel in a bikini on his wall.
  
  I don't know that I think that's a 1-to-1 comparison. If you looked at this picture with no foreknowledge of where it was from or what it was like uncropped you'd think it's a perfectly innocent headshot of a woman. It's not like strapless tops or dresses don't exist, and the hat suggests she's clothed so there is no reason for the mind to jump to the idea that she's naked unless you already know it's from Playboy.
  But I don't know, I might just not get it. I had no idea the shoulder was such a big deal so it might just be me there's something wrong with. I feel like I missed a memo. Which does happen a lot, to be honest.
- that was my initial reaction until reading the article. some perspective that kind of helped was that the backlash to it was in the 90's. porn existed in more places than just in magazines but it was still rare. to have it appear on the front line of a technology research field was just jarring to institutions at the time. we kind of take for granted how casually today we can just reference things in professional settings.
  but puritanism can always come back

Here's a 30 minute video on this topic for anyone interested.

Richard Hendricks (the main character in HBOs Silicon Valley) has this photo on his wall (he makes a revolutionary compression algo)
He also has a photo of Huffman, another famous compression dev

Nerds stop being horny all the time challenge

I didn’t know about this before now. A quick Google search reveals this image has shown up multiple times as a Easter egg in Silicon Valley episodes.

That image was used for a project I had to do about 7 years ago. Can't recall exactly what it was, but it involved binary and that image. Not sure if I did that project, though. This time around, we had no images to deal with, though I reckon that might just be to switch the assignment every year to stop people from taking the previous year's project (I could be wrong, though. But I think I've heard they used an image last year, though I think it wasn't Lenna, which is good)

Hmmm