Tutorials

Indexing Files

To create a new index:

ddb init

To add images to an index:

ddb add images/
ddb add images/DJI_0018.JPG
ddb add images/*.JPG

To remove images from an index:

ddb rm images/DJI_0018.JPG

To sync an index after filesystem changes:

ddb sync

Projecting an image onto a map

https://user-images.githubusercontent.com/1951843/68077866-001de800-fda2-11e9-895f-b5840d9d047d.png

You can project images onto a map. This does not require an index and can be done on-the-fly.

ddb geoproj images/DJI_0018.JPG -o projected/

Browsing data with QGIS

You can explore the indexed data with a program such as QGIS. The index creates a .ddb/dbase.sqlite file when running the ddb init command. This is a SpatiaLite database and can be imported by adding a new SpatiaLite layer.

Viewing Flight Path LineString

https://user-images.githubusercontent.com/1951843/66138811-3dd5f800-e5cd-11e9-816d-a0efa39ccca5.png

Create a new query similar to:

SELECT AsGeoJSON(MakeLine(point_geom)) FROM (SELECT point_geom, json_extract(meta, '$.captureTime') as captureTime FROM entries ORDER by captureTime ASC);

The ‘point_geom’ column contains the GPS locations, while ‘polygon_geom’ has the footprint extents. Footprint extents can be calculated only if gimbal orientation and camera parameters are present.

Extracting GPS locations/footprints to GeoJSON

You can quickly extract the locations of images to GeoJSON via:

ddb info *.JPG -f geojson -o gps.geojson

Or for image footprints:

ddb info *.JPG -f geojson --geometry polygon -o footprint.geojson