Instructions for Color Measures

To use, click on “Choose File” and browse your directories for a json file with the RGB values for the colormap of interest. Json files for the example colormaps used in the paper can be downloaded from this site.

Output from the tool consists of:

  • An image of the colormap.
  • A set of local and global measures for the colormap (see paper for full details). The measures are calculated using one of the metrics ∆E1976, ∆E2000, or the Euclidean distance in CIECAM02-UCS.
  • The average speed correlates with the discriminative power – higher local/global speeds correspond to higher local/global  discriminative power.
  • The standard deviation of the speed anti-correlates with the uniformity – lower deviation in local/global speed correspond to higher local/global uniformity.
  • The minimal speed indicates the invertibility and therefore the legend-based order – the colormap suffices local/global legend-based order if the minimal local/global speed is strictly positive.
  • The minimal triangle side difference indicates the intuitive order – the colormap suffices local/global intuitive order if the minimal local/global triangle side difference is strictly positive.