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Image Dithering: Eleven Algorithms and Source Code

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Re: Image Dithering: Eleven Algorithms and Source Code

#21

Post by startling »

derefr wrote: post #20
startling wrote: post #19

Earlier quoted context omitted.

> A lot of people could theoretically bond with one-another over a shared attraction to a given gender. OK? That's not what's happening here.

The point you were making wasn't about what was or wasn't happening here , though; it was about what such statements "usually [serve to do] ... in geek contexts." Geek contexts involve a lot of the types of people I mentioned. (For example, according to a recent survey of LessWrong members, there are actually more transwomen than ciswomen in that community.)

The full quote:

> In geek contexts, they are usually a way for heterosexual men to bond over their common attraction to women. This is othering for anyone who is not a heterosexual man, including, obviously, women, and contributes to their invisibility in the field.

There's nothing here suggesting that that shared sexuality can't be used as a bonding mechanism among other groups. Just that in "geek contexts" it's usually intended as a bonding mechanism between straight men, and that this is othering to people who aren't straight men.

Re: Image Dithering: Eleven Algorithms and Source Code

#22

Post by semi-extrinsic »

This article is really nice. I used it as my starting point when I once won a code golf competition on image quality in dithering. Using Fortran.

The algorithm is based on Sierra Lite, but I added a random element to the direction in which the error is propagated. This removes essentially all dithering artifacts.

http://codegolf.stackexchange.com/questions/26554/dither-a-g...

Re: Image Dithering: Eleven Algorithms and Source Code

#23

Post by mozumder »

startling wrote: post #5
mynegation wrote: post #4

Back when I was at university, we had a computer graphics course. Each week we got new assignment that we needed to program, write to a floppy disk (it was before Internet became widely available) and give it to the prof next week. Dithering was one of the assignments. We were required to implement black-white quantization and then Atkinson and Floyd-Steinberg. We were given the freedom to choose our own images. Duri…

Gross.

Completely inappropriate comment.

Re: Image Dithering: Eleven Algorithms and Source Code

#25

Post by spiderfarmer »

startling wrote: post #15
xiphias wrote: post #11

Earlier quoted context omitted.

How can an virtual object (a photo of a woman seen on a monitor) be objectified? The model meant that photo to be used as an object (looked at). If she wanted people to understand her personality more, she would have just written a book.

These are the kinds of things, specifically, that gross me out about this story: (from http://geekfeminism.wikia.com/wiki/Sexualized_environment ) * In geek contexts, they are usually a way for heterosexual men to bond over their common attraction to women. This is othering for anyone who is not a heterosexual man, including, obviously, women, and contributes to their invisibility in the field. This sensation of excl…

  This is othering for anyone who is not a heterosexual man
I disagree. Women look at other women as well. It's very natural to feel excluded when groups of people over something you don't get excited about, whatever the subject. If, for example, people can contain their excitement about Magic cards when I'm around, I'm fine.

  There is a long tradition of sexual images, suggestions and approaches being used to shame, scare, harrass or brutalise women.
Yeah, so a picture of a professional model is something completely different. You are dragging this point into the discussion but it doesn't add anything.

  ...they may reveal themselves as too sexual.
Just bring it back to basics. Men have dicks they want to use, women want to be admired. If people could just respect eachother while taking these basic needs into account, everyone would be fine.

--

I am happy that people here in the Netherlands are so much more tolerant when it comes down to things like sexuality, public intimicy and nudity. It seems to me that in the US people get offended very easily and want to limit another persons freedom of expression just so that they can be offended a little bit less.

Re: Image Dithering: Eleven Algorithms and Source Code

#26

Post by mynewtb »

startling wrote: post #15
xiphias wrote: post #11

Earlier quoted context omitted.

How can an virtual object (a photo of a woman seen on a monitor) be objectified? The model meant that photo to be used as an object (looked at). If she wanted people to understand her personality more, she would have just written a book.

These are the kinds of things, specifically, that gross me out about this story: (from http://geekfeminism.wikia.com/wiki/Sexualized_environment ) * In geek contexts, they are usually a way for heterosexual men to bond over their common attraction to women. This is othering for anyone who is not a heterosexual man, including, obviously, women, and contributes to their invisibility in the field. This sensation of excl…

Do you have an alternative unbiased source?

Re: Image Dithering: Eleven Algorithms and Source Code

#28

Post by 1wd »

Another fun fact I always think of when dithering comes up is how Tim Sweeney's software rendered or the original Unreal game used dithering instead of bilinear interpolation for texture mapping. This was very impressive at the time.

http://www.flipcode.com/archives/Texturing_As_In_Unreal.shtm...

Re: Image Dithering: Eleven Algorithms and Source Code

#29

Post by seanwilson »

Great and easy to follow article!

> For simplicity of computation, all standard dithering formulas push the error forward, never backward. If you loop through an image one pixel at a time, starting at the top-left and moving right, you never want to push errors backward (e.g. left and/or up).

Would the image look a lot different if you dithered it backwards from the bottom right pixel?

Are there dithering algorithms that consider the error in all directions instead of pushing the errors forward only?

Re: Image Dithering: Eleven Algorithms and Source Code

#30

Post by dividuum »

There is another interesting application for dithering that I've read about in the recent Uncharted 4 Brain Dump (Ctrl-F for "Dithering") here https://redd.it/4itbxq: Use dithering instead of alpha blending to fade out close objects. Alpha blending can be quite expensive while dithering just omits pixels. The result looks like this: http://allenchou.net/wp-content/uploads/2016/05/dithering-1-... (best visible at the top left corner).
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