Re:How Virtual Textures Really Work
by DiggyJohnson on Friday February 06, 2026 @06:25PM
(#46919566)
Who is Lenna?
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A copyrighted image of a nude model elected for no obvious reason has a test image in the University of South California by some pervs and then used in a lot of papers as a test image.
Or, a standard cropped image of a playgirl used in the field of image processing.
Re:How Virtual Textures Really Work
by groundzeros2015 on Friday February 06, 2026 @08:37PM
(#46920436)
It’s perverted now?
It's literally cropped pornography.
Re:How Virtual Textures Really Work
by groundzeros2015 on Friday February 06, 2026 @08:58PM
(#46920558)
Is a nude picture perverted?
No. That is not the question.
The question is "do you hang out with an erotic magazine at work ?" and "Is it normal ?"
Re:How Virtual Textures Really Work
by groundzeros2015 on Friday February 06, 2026 @11:54PM
(#46921423)
No I think the social context is inappropriate. However I do not think possessing or liking such a picture is perverted. I also do not thinking a cropped version of the picture which has no sexual content is inappropriate.
"elected for no obvious reason" isn't quite right, as a test image for computer graphics it has regions of very high frequency detail and regions of very low frequency detail which make it easier to spot various compression artifacts, and it makes a good study for edge detection, with both very clear edges along the outline, but more subjective edges in the feathering.
It's redish. Ok it has a blur and details on the foreground but could have been any image with blurred background and a face.
"very low frequency detail", we are talking about a 512x512 picture here, it has low and high frequency details (FFT speaking) like most photos.
"Good for edges detection" doesn't mean anything. Like, is the image good for edge detection or the algorithm is good at detecting edges ? What does "subjective edges" even mean ? Does it mean hard to spot ?
That looks like technical reasons but it just noise. They literally grab a playboy magazine and decided it was well enough (and indeed, it wasn't that bad, yes). Still not professional. The message is "We have playboy magazines at work and we are proud of it".
Try out running different edge detection algorithms on that image and you will see that there is a lot of disagreement amongst them in the feathering region. Exploring what the differences are, and how the algorithms lead to those differences helps build intuition about the range of things we might call an "edge", and which algorithm is appropriate for a particular task at hand.