I originally made this post to suggest an alias to a few tags, though it's better how they are than what I proposed.

This thread's now more of a discussion on the different colour tags and how posts should be tagged with them.

nah, no color could also mean black and white. it needs to be aliased to either monochrome (no color is monochrome regardless of whether the tagger meant grayscale or black and white) or it should be disambiguated. aliasing it to grayscale could super easily get black and white images get mistagged with grayscale.

hiekkapillu said:
nah, no color could also mean black and white. it needs to be aliased to either monochrome (no color is monochrome regardless of whether the tagger meant grayscale or black and white) or it should be disambiguated. aliasing it to grayscale could super easily get black and white images get mistagged with grayscale.

Looking at this again I definitely see your point, and thinking more on it no_colour would imply black_and_white or greyscale, and therefore monochrome.

My earlier logic was definitely a bit backwards, thinking that monochrome had images which could have colour, therefore no_colour didn't fit, despite, obviously, monochrome most often being used for images without colour.

I'm kinda embarrassed at that to be honest.. All I can say is that I've been pretty damn tired recently.

Since we're talking about these tags, I hope you don't mind me asking for some advice/clarifications. I've been coding an e6 tag bot, which works great for ratios and resolution tags, but I was hoping to be able to clean up the monochrome/greyscale/*_and_white/sepia tags a bit with it as well.

It's pretty easy to determine monochrome/sepia/*_and_white tags, but black_and_white gets confusing. The wiki notes that black_and_white isn't greyscale.

but where do these black_and_white images fit in:

post #1866461 post #1861959

For the first, if it was me uploading it I'd probably say it was greyscale line_art, rather than black_and_white.

The second is mostly black and white, but especially around the horns it goes greyer.

Essentially, when does black become grey? And should black_and_white only include images that have black, or nearly black, and white pixels? Though that might exclude quite a lot of drawn art.

With the tagbot, at least for the moment, I'd only feel comfortable adding the black_and_white tag to posts that are only dark black and light white, with no grey, and maybe removing it if there's any brighter colour. I wouldn't want to start tagging/untagging greyscale when the boundaries between grey/black are a bit vague.

Looking at monochrome -greyscale -sepia -*_and_white it really looks like an area that needs tidying up. I think a lot of people also tag black_and_white presuming it's the same as greyscale, the same as a "black and white movie" isn't only black and white, and not called a greyscale movie.

As a tag suggestion, maybe black_and_white should be aliased to monochrome, and a new tag created called only_black_and_white, for what black_and_white was originally intended, to avoid mis-tagging by people who don't read the wiki on it.

With the topic of this thread, I couldn't help but make/link a shades of grey joke.

Technically, black and white would be achrome rather than monochrome as that is what achroma literally means: "no color".

On the other hand, monochrome is using variations of only one color ("one color"). This includes grayscale.

Using two colors: dichrome. Three colors: trichrome. Beyond that, you'd probably want to use polychrome.

Thus, black_and_white should not be aliased to anything, with the exception of achrome, but I would recommend the latter be aliased to black_and_white since users would understand what that means better.

Monochrome should be limited only to images that use more than one shade (+black), hue (+gray), and/or tone (+white) of only one color. So, for example, a blue monochrome picture needs to have at least two blues in it.

The puzzle is the pictures that might qualify as black_and_white but use a different color than black (or white, if it's a negative). The most obvious solution might be to tag them as red_and_white, green_and_white, blue_and_white, etc. Even so, someone might still want to have an umbrella term for all these "color_and_whites", so perhaps we could stretch a definition and have them all imply achrome.

Clawstripe said:
Technically, black and white would be achrome rather than monochrome as that is what achroma literally means: "no color".

*pulls his hair out*
Starting to regret saying I'd make a bot to handle this stuff :)

Seriously though, I feel like these tags really need tidying.

Clawstripe said:
Using two colors: dichrome. Three colors: trichrome. Beyond that, you'd probably want to use polychrome.

Well, at least I could auto-tag them based on different hues.

Clawstripe said:
Thus, black_and_white should not be aliased to anything, with the exception of achrome, but I would recommend the latter be aliased to black_and_white since users would understand what that means better.

I still think black_and_white should be aliased to monochrome, as if I hadn't seen the wiki, I'd presume it meant greyscale. At least that way it covers both accidental tagging and correct tagging of it, as both are monochrome.

Clawstripe said:
Monochrome should be limited only to images that use more than one shade (+black), hue (+gray), and/or tone (+white) of only one color. So, for example, a blue monochrome picture needs to have at least two blues in it.

Sounds good, and I think that's how it's defined on the wiki, except it doesn't say two hues.

How would this be tagged:
post #1848785

Literally it's not monochrome, or sepia. As there's more than just brown. So dichrome? But then would sepia be tagged along with dichrome?

Clawstripe said:
The puzzle is the pictures that might qualify as black_and_white but use a different color than black (or white, if it's a negative). The most obvious solution might be to tag them as red_and_white, green_and_white)), {{blue_and_white, etc. Even so, someone might still want to have an umbrella term for all these "color_and_whites", so perhaps we could stretch a definition and have them all imply achrome.

Well monochrome, as you said earlier, would be black, white, and one hue. So monochrome + *_and_white/black

I think an umbrella term would be good. I also thought of a wiki page similar to hoe the equine one is arranged, to give an idea of all the different colour tags. This one exists, but I think it needs a revamp to not be so cumbersome to navigate.

I think I'll change the title of this thread as well, it's more about colour tags in general now, rather than the (wrong) aliases I suggested in the first post.

spot_color

Ratte said:
spot_color

Ah, thanks for that, I didn't realise that was a tag :)

Pupslut said:
Ah, thanks for that, I didn't realise that was a tag :)

No problem. A lot of people don't.

Sorry for bumping my own thread, but I could really use some input on black_and_white/greyscale tagging, and any ideas people have for detecting spot_color, in an otherwise monochrome image, vs one that's just partially coloured.

So to start with, what counts as black/grey? And should black_and_white only be images like this:
post #1868875 post #1850350

Whereas anything less than dark black and bright white is only greyscale, so these would be un-tagged with black_and_white and added to greyscale:
post #1866461 post #1861959 post #1860851

I'd probably say if >5/10% of the image wasn't either a dark shade of black or bright white then it should be greyscale.

I feel that that's how things could work, but it's just on whether other people agree. I don't want to start mis-tagging tons of images.

The spot_color tag makes it a bit more complicated, so I'll probably skip images with partial colour in till I've gotten a decent algorithm that I'm happy with. I'm thinking if an otherwise monochrome image is <10% colour, then to draw a circle around the spots of colour, and if they're small circles then add spot_colour. Though I don't think I'd be able to confidently remove it, as there's things like this:

post #1698195

Spot_color says "small, specific area", but how small is small? And unless someone can help with this I feel it'd be best to not have my bot touch images with colour, as it's hard to tell the difference between a partially coloured image and an image where spot_colour would apply.

Then a few images are tagged as monochrome with spot colour despite being full colour, as people have copied tags across from earlier versions of posts but not removed them. I'm just trying to think of how to tell the difference between full colour and monochrome with a few spot colours of different hues, so any help on that would be appreciated as well.