Graphic map load is the fullness of a map covered by map symbols and labels influenced by their parameters (shape, size, fill etc.), spatial distribution and density.
It is relative to the map size and is usually measured on scale 0–100%.
Graphic Map Load Measuring Tool (GMLMT) is available for download under the licence CC BY-SA. The tool is a Python script for open-source graphic editor GIMP. After putting the file into the extensions folder of GIMP, you can find the tool in the menu Filters → Edge-Detect.
GMLMT is suitable for all raster representations of a map in RGB (RGBA) colour space. To provide comparable results, the original map dimensions and 100 DPI image resolution are recommended. GMLMT measures graphic map load of the whole map or of a user-selected extent defined by GIMP built-in tools.
User manual – detailed instructions for installing and measuring using GMLMT
GMLMT 1.4 (build 221120) – clearing code, fixing errors with labelling maps with transparency
GMLMT 1.3 (build 210401) – improvements in visualisation grid calculation and labelling
GMLMT 1.2 (build 210112) – export of a report into a text file (in Users folder), minor code upgrades
GMLMT 1.1 (build 201125) – regular grid for visualisation of map load distribution
GMLMT 1.0 (build 200709) – first official release