SHP boundary import from elsewhere

ESRI Shapefile (SHP) is the most widely-used vector GIS file format. Many agricultural databases (national farm registries, Cargill, Syngenta, your own Excel-exports) issue field boundaries as SHP.

DroneField’s built-in PROJ library converts any coordinate reference system (CRS) to WGS84 — including EOV for Hungarian data.

What you need to know

An “SHP file” is really 4–6 files together:

File	Purpose
.shp	The geometry (polygons, lines, points)
.shx	Index for .shp
.dbf	Attribute table (name, area, category, etc.)
.prj	Coordinate reference system — critical
.cpg	Character encoding hint (not read by DroneField)
.sbn/.sbx	Spatial index (optional)

Always include the .prj file — it tells DroneField the CRS of the SHP.

Import flow

1. On the map, open the Boundary toolbar (click the Field boundaries layer in the sidebar).
2. Click Import.
3. Pick Import Shapefile….
4. A file picker opens. Select the .shp file (the others are read automatically).
5. The Shapefile import dialog opens. Choose the Mode:
   • Auto-detect — reads the CRS from the .prj (e.g. “HD72 / EOV (EPSG:23700)”). If the .prj is present but its EPSG code is not recognised, the full WKT is passed to PROJ.
   • List — pick the CRS from a list (use this when there’s no .prj).
   • EPSG code — type a code, e.g. 23700 or EPSG:23700.
   • WKT direct — paste a WKT description, passed to PROJ as is.
6. Click Import. The coordinates are converted to WGS84 via PROJ, and every polygon appears on the map as a field boundary.

Common source CRS systems

Source	CRS	EPSG code
MePAR (FÖMI, Hungary)	HD72 / EOV	EPSG:23700
OpenStreetMap export	WGS84	EPSG:4326
Google Earth KML → SHP	WGS84	EPSG:4326
EU LPIS (other member states)	UTM 33N / 34N	EPSG:32633 / 32634
Old military 1:25 000 (Hungary)	Dealul Piscului 1970 / Stereo 70	EPSG:31700
DJI Pilot Mission Planner export	WGS84	EPSG:4326

With a .prj file these are detected automatically; otherwise pick them in List or enter the EPSG code.

EOV → WGS84 — the most common case

The Hungarian HD72 / EOV (Egységes Országos Vetület) is the CRS of most official Hungarian shapefiles.

Example:

• Input (EOV): (650 000, 235 000) — near Budapest
• Output (WGS84): (47.5°N, 19.05°E)

DroneField uses PROJ 9.4 — error is < 1 cm, well below typical drone GSD.

What the .dbf attribute file contains

DroneField uses the .dbf only for the boundary name. It takes the first non-empty field from: NAME, Name, name, PLOT_NAME, FIELD_NAME, FIELDNAME, ID_NEV, MEGNEVEZES, NEV, Nev, TABLA_NEV, DUL_NEV. If none of these exist, the first non-numeric text field is used; failing that, the polygons are numbered.

Other attributes (area, type, soil class, partner ID) are not imported, but the .dbf is left untouched — viewable in QGIS.

Obstacles and no-spray zones

Every imported polygon becomes a field boundary — a type column in the .dbf is not evaluated. If the SHP also contains obstacles or no-spray zones, change their type in DroneField after import.

Character encoding

Hungarian accented characters (Á, É, Ő, Ű) can be tricky. The .cpg file is not read; DroneField tries in this order:

1. The encoding named by the .dbf header (language driver), if set
2. UTF-8 (modern, recommended)
3. Windows-1250 (older Hungarian SHPs)
4. ISO-8859-2

If characters appear mangled ("T�rnok" instead of "Tárnok"), convert the SHP to UTF-8 in QGIS (Export → Save Features As…, Encoding: UTF-8) and import it again.

What NOT to do

• Don’t ZIP the SHP before import — the picker doesn’t unpack. Extract first.
• Don’t separate .shp from .prj — they must live in the same folder.
• Don’t overwrite an actively used SHP — the imported boundary lives in the project now; the source file no longer drives it.

Exporting also works

To export to SHP (e.g. to the partner’s GIS system), use the Boundary toolbar’s Export → ESRI Shapefile option. DroneField exports in WGS84; the partner converts to their system if needed.