Skip to main content

Notes on Color #5: Projecting Munsell Colors

Before the digital era, the Munsell Color System was probably the best perceptually uniform color system with hue, chroma and value components. It is also used nowadays.

The 1943 Munsell renotations (with portion cut away).
Source: Wikipedia CC BY-SA 3.0

When reading the introduction page of Oklab, I learned about the idea of projecting Munsell colors into diffrent color space. I find it an intuitive and fun way to study color space. Who does not like colorful demos?

Here we have to assume the quality of the Munsell data, which might not be 100% scientific. Anways I think it should be good enough, as proved by generations of aritist.

With this assmption, we may examine munsell colors in the target color space, and observe the following:

- Do the points with same chroma form a perfect circle? Are they distributed evenly?
- Do the points with same hue form a straight line? Are they distributed evenly?
- For luminance/brightness, actually I assume decient color spaces are already good enough. 

The Results

Here are projections of Munsell colors with value = 5.

My farvorites: CAM16-UCS and Oklab. 


CAM16-UCS
Oklab

Others.

Note that some models are not even designed for perception. They are simply presented here for fun.

CIELAB
CIELUV
Hunter Lab

IPT
OSA UCS

SRLab2
YCbCr
CIEXYZ
xyY


HSV
HSL

Comments

Popular posts from this blog

A Rocky Migration: Moving from docker-compose to Podman and gVisor

I've been running a few containers for several years. They were all running under rootless Docker with a single user. Initially, I planned to  migrate the containers to VMs , but I couldn't get a stable workflow after about two months of effort. Later,  gVisor caught my attention , and I decided to migrate to Podman with gVisor instead. The new plan is to run each container with  --userns=auto  and use Quadlet for systemd integration. This approach provides better isolation and makes writing firewall rules easier. I'm now close to migrating all my containers. Here are a couple of rough edges I'd like to share. Network Layout I compared  various networking options  and spent a few hours trying the one-interface-per-group approach before giving up. I settled on a single macvlan network and decided to use static IP addresses for my containers. To prevent a randomly assigned IP address from conflicting with a predefined one, I allocated a large IP range for my ...

GameConqueror 0.09 -- Linux Game Hacking Tool

If you are a game hacker If you've been looking for a `CheatEngine for Linux` Then you can't miss this. ============================================== GameConqueror is a game hacking tool for linux, it's written in PyGTK and uses scanmem as its backend. It's supposed to be with most useful features of CheatEngine for Linux. Currently, I've implemented almost everything about scanning, involving variant data types and scan types: Data Types: int{8/16/32/64}, float{32/64}, unknown type(int or float) and unknown width(will try each of them), byte array and string Scan Types: equal, greater, less, changed, unchanged, increased(by), decreased(by) This should be enough for most cases, so I decided to release it at the current status. ============================================= Here's how you can get it PPA (for Ubuntu users) https://launchpad.net/~coolwanglu/+archive/scanmem (I've not test it in 32bit environments or Jaunty, do please inform me if it doe...

Fix Google Security Code

Google Security Code (http://g.co/sc) is one type of 2-step verification. This is particularly useful when security keys and passkeys are not available. I have been using it in my LXC containers, until today I found out that it stopped working. It just kept saying "The code is invalid". It is easy to rule out some factors: The code works on other browsers on my laptop. The code works on other devices that are directly connected to the router. So it appears that Google also checks IP addresses besides the security code. Recently I have IPv6 enabled, so most devices that are directly connected to the router have both IPv4 and IPv6 addresses. But  I only enabled IPv4 for my LXC containers. So I guess when a code is generated by device A and used by device B, Google should be able to check that device A and device B are closely located. But in my case, IPv6 address appears on device A but not on device B, which may look suspicious. To fix the problem, I just needed to disable IPv...