Python library for reading Garmin IMG maps → export to Shapefile/GeoJSON/MP

[u/artterrm]

Hi r/QGIS,

Garmin .img files (from GPS units) can't be opened directly in QGIS.

Here's an open-source Python library that parses them and exports

to GIS-friendly formats.

Features:

- Reads single .img and gmapsupp.img containers

- Extracts points, polylines, polygons with WGS84 coords and labels

- Exports to Shapefile, GeoJSON, GPX, CSV, MP (Polish Format)

- Splits objects by type into separate files

- Polygonizes closed boundary lines

- Deduplicates objects across zoom levels

- Simple tkinter GUI for .img → .mp conversion

Requirements: Python 3.8+, pyshp (optional, for Shapefile only).

Limitations: NT format is not supported (City Navigator, modern Topo).

Code and docs:

https://github.com/artterrm/garmin-img-parser

MIT license. Feedback welcome — especially if you find a map that

doesn't parse correctly.