@EineGeschichteDerStadtKoelnPod @Lokal_K ups  🙃 … das Lokal K ist ein lokaler Community-Raum in Ehrenfeld, jeden Donnerstag treffen sich dort Aktive der „hiesigen“ #Wikipedia-Community, aber der Raum wird auch von verwandten Geistern wie #OSM, #oklab u.a genutzt. Vor Ort wird an Projekten gearbeitet, gequatscht und zusammen gegessen.  https://de.wikipedia.org/wiki/Wikipedia:Lokal_K

#ReleaseThursday This is actually the 2nd bunch of #ThingUmbrella releases since the weekend (which I completely forgot to notify about). The main highlights are:

https://thi.ng/color - added #Oklch support, update #Oklab conversion matrices (to latest spec), updated/improved/fixed CSS color parsing & serializations (more input formats, wider support for using percentages in more places), added serialization options for CSS Color Module Level 4, more docs

https://thi.ng/hiccup-markdown - major new version w/ completely new & extensible parser to transform #Markdown (with custom extensions[1]) into a proper abstract syntax tree and then transform elements via user defined handlers into arbitrary data structures. The default handlers generate a https://thi.ng/hiccup tree. More info in the package readme and the readme of this interactive parser & live preview demo: https://demo.thi.ng/umbrella/markdown/

[1] The syntax extensions include blocks of arbitrary metadata attached to _any_ blocklevel element (e.g. headings, paragraphs, tables, lists etc.) and custom typed blocks of content

As usual, please see changelogs for other updates:

https://github.com/thi-ng/umbrella/blob/develop/README.md#latest-updates

Happy Coding! 😍​

TIL #SwiftUI’s Gradient seems to interpolate in #OKLab – worth keeping in mind when trying to match Figma (which used sRGB from what I can tell) or other design apps.

Advice from watching @svgeesus's "Escaping the sRGB Prison" talk: if you want to polar color mixing use #Oklch, if you want linear color mixing use #Oklab. See also: https://developer.mozilla.org/en-US/docs/Web/CSS/color_value/oklab

Alright, now we're cooking. #matplotlib is not that bad :)

#animation #math #color #oklab

I also like how some patterns start to emerge. Here for instance the "a" component (green/red) is almost perfectly aligned linearly to the "b" component (blue/yellow).

Note: if you're confused about the 3D perspective view, that's because of a bug in #matplotlib (https://github.com/matplotlib/matplotlib/issues/24767)

#color #research #oklab

I'm now able to make all kind of combinations of the following params:
- honor or not the weights of the colors
- use variance or simpler heuristic for box selection
- normalize or not the variance
- refine with k-means with arbitrary iterations
- work in sRGB, linear or #OkLab

I'm tempted to replace the median-cut with a PCA as first pass, add an axis-variance parameter, and maybe adjust box selection accordingly).

Then I'll need to generate and study all kind combinations…

#color #research

I'm currently experimenting with palette quantization algorithms. Here is a fig with 2 palettes (represented in 3 color spaces each): the reference computed in sRGB (top), and the new in perceptual (bottom, #oklab) .

For some reason in the new palette (bottom row) the colors are way more sparse with zebra gaps, as if there were less colors (this is not the case). As a result the original picture quantized with the new palette suffer from terrible banding.

I'm annoyed, but not defeated.

#color

✨ New blog post! Porting #OkLab colorspace to integer arithmetic

http://blog.pkh.me/p/38-porting-oklab-colorspace-to-integer-arithmetic.html

#colors #math #dev #C #blog

I just discovered what I think is THE BEST color picker on the internet**. Seriously.
❤️❤️❤️
🎨🎨🎨
🌈🌈🌈
📊📊📊
🍾🍾🍾🍾🍾❤️❤️❤️❤️❤️

https://oklch.evilmartians.io/#45.3,0.108,102.285,100

AND, as if that wasn’t enough — they wrote an incredibly helpful and in depth blogpost as well.

https://evilmartians.com/chronicles/oklch-in-css-why-quit-rgb-hsl#oklch-vs-oklab--lch-vs-lab

These use #OKLab and #OKLCH, which are for many situations the best colorspace to use (especially for color on the web).

**technically, “my discovery” was a Git update. But, it was a most exciting Git update 🥳

@jhilden The infuriating thing about this is: #Adobe uses #oklab for their gradients, so they are clearly aware of it. So why isn’t it an option for the colour pickers?

Yay, I got my fixed point #OkLab implementation working and the precision is much better than my expectations.

Comparing it against the official float/libm implementation on the 16M+ sRGB colors raises a maximum error of 0.000047.

It's unfortunately slower right now: 526.0ms ± 4.9 ms vs 816.2ms ± 4.1 ms

Quick color/programming question:

Does anyone know of a good tool/website for quickly comparing a block of hex codes (or similar) against each other?

Ideally I could paste in 5, or 8, or 50 #Color codes…and get as output a comparison matrix of differences as #DeltaE2000 or #OKLab

I’ve previously used a behemoth #Excel + Google sheets to do this, but it was absurdly manual to set up all of the lookups…and there have to be others who have already made something like this?? #Colorjs

For people who work with #OKLab, #Color, #SVG, or #ColorProfiles...Are you familiar with Mark Fairchild and Yuta Asano's work on characterizing Categorical Observers?

https://onlinelibrary.wiley.com/doi/10.1002/col.22493

I'm trying to see if anyone has experience or advice on how to implement it.

@Justin_Lind @havegum I think @gka had a JS library for this, but the name escapes me at the moment. Dunno if it's been updated with newer color spaces like #OKLab and #OKLCH

@havegum
#OKLab is currently the best (I believe, with #LAB being the older and maybe second-best place to operate in) #ColorSpace in which to make all of these transitions & color ramps.

Here are two useful sites, which can hopefully get you headed in the right direction:

https://bottosson.github.io/posts/oklab/

https://www.joshwcomeau.com/gradient-generator/

A mmber of our #oklab analyses the state of #opendata portals in Germany, and developed a processing for the metadata of #ckan portals, aggregated and visualises this in #tableau.

You can have a look here:
https://public.tableau.com/app/profile/michael.riedm.ller/viz/bersichtOpenDataPortale/Dashboard2

And here is a peek into a part of the preprocessing chain necessary, implemented with #knime:

#Kiel bekommt ein Open Knowledge Lab! Mach mit! #OKLab
https://www.webmontag-kiel.de/2020/02/10/kiel-bekommt-ein-open-knowledge-lab-mach-mit/

#Kiel bekommt ein OK Lab!

Auftaktveranstaltung für das #OKLab Kiel ist am 17. Februar 18 Uhr in
den Räumen von opencampus.sh in der Kuhnkestraße 6 im Wissenschaftspark.

Es gibt ein wenig Input zum Thema "OK Lab" und #OpenData. Anschließend wollen wir überlegen, was wir im OK Lab Kiel machen wollen. Also gerne schon Ideen für Projekte mitbringen.

Hier kann man erfahren, was ein OK Lab ist: https://www.codefor.de/ueber/

Herzlich Willkommen zum WebMontag in Kiel!
Jesper Zedlitz "Mr. Open-Data" will ein #OKLab in #Kiel gründen. Was das ist und warum man da mitmachen will, erzählt er gerade. #wmki