Censor

censor is a standalone palette analyser inspired by DawnBringer's Palette Analyser for GrafX2 and having a compatible layout. It helps creating and evaluating restricted palettes by providing visualisations and highlighting certain properties.

Examples

Installation

Install the rust toolchain using rustup or the repository. Then run: $ cargo install censor-analyser

Usage

To see all the flags and descriptions, pass --help to censor and its subcommands.

censor analyse

The default output is written into plot.png in the working directory even if the file exists. Specify another output file with -o another.png argument. To use black, grey and white for UI instead of choosing palette colours, pass the -g flag. The illuminant is a daylight illuminant with the white point generated by the temperature T in Kelvins, 5500 by default; the option -T may be used to redefine T; the option -D may be used for the following presets: -D50, -D55, -D65. If the input image is png or jpeg and it has an embedded colour profile, that profile will be copied into the analysis image. Specify -j to test the experimental multithreaded mode.

Analyse a palette from an image input.png: $ censor analyse -i input.png Analyse a palette from a text file input.hex: $ censor analyse -f input.hex Analyse a palette from manually specified hexcodes 2e3037,ebe5ce: $ censor analyse -c 2e3037,ebe5ce Analyse a palette from lospec.com aurora: $ censor analyse -l aurora

censor compute

Palette input and illuminant options are the same as for censor analyse. In addition, there are options for specifying which metrics should be computed. -a, --all activates all the metrics. There are also flags for individual metrics (see the help page). The output is formatted in csv to be script-friendly.

censor daemon

Start daemon mode on port 8008: $ censor daemon -p 8008 Once the daemon is running, send commands after connecting to the port (one command per connection). The syntax is the same as for the command-line app, but: 1. You should omit the first censor. 2. The daemon command is not available. 3. The -o option for analyse is no longer optional.

An example of a valid palette analysis request (assuming that the daemon is started on port 9876 on a Linux/Mac machine): $ echo "analyse -l antiquity16 -o plot.png" | nc localhost 9876

On success, OK is returned. On error, ERR is returned and more error info is printed in the next lines and also into daemon's stderr.

Features

• Analyse palettes of 2-256 colours
• All widgets use CAM16UCS with perceptual colour distances
• Load colours from command line arguments, text files, images and Lospec
• Daemon mode for large amounts of analysis requests
• WASM support for analysing palettes on web pages client-side (currently broken)

Widgets available

• Rectangular hue-lightness with fixed chroma
• Spectral colours (with the non-spectral CIExy line added)
• Spectral box (with y parametrising a parabola going through pure black, the spectral colour and pure white)
• Indexed palette
• Close colours (with different lightness weights)
• Internal similarity (which is (mean_d/min_d)/n^(2/3))
• Acyclic check
• "Spectral" distribution (from hue-mapping nearest spectral colours relative to the white point)
• "Temperature" distribution (normalised -log(CCT), might be changed later)
• Greyscale with differing lightness weights
• Cubes showing the colours in CAM16UCS space from different angles
• Hue-lightness plot
• Useful colour mixes (i.e. producing points that are further from other palette points)
• Lightness-chroma bars
• Lightness-sorted colours and neutralisers
• 12-bit RGB approximation
• Polar hue-chroma plot
• Polar hue-lightness with fixed chroma levels
• Complementaries