Using 'ogr2ogr' algorithm in QGIS to transform SHP to GPX

Question

So I am trying to convert a LineString shapefile into GPX using the 'gdalogr:ogr2ogr' algorithm in a QGIS python plugin.

The problem is that I alway get routes instead of tracks, even if I specify the option 'FORCE_GPX_TRACK=YES'. The input is actually a LineString, not a MultiLineString (by default, LineString are created into the route layer). But the 'FORCE_GPX_TRACK' option is supposed to create it as a track...

Here is the code:

processing.runalg("gdalogr:ogr2ogr",inputf,16,'FORCE_GPX_TRACK=YES',self.GUIControl.output_path + os.sep + "GPX" + os.sep + filename)

EDIT:

Maybe I should mention that I am trying this on QGIS 2.4 on Linux (debian)

I tried 'gdalogr:convertformat' on QGIS 2.12 on Windows and it wrote the GPX file with the correct geometries, as tracks. But, there are no attributes though. Maybe I should use '-select field_list' option after -lco ?

I will try it tommorrow, because i'm on my windows machine right now. I just wanted to post an update of my problem to let you know i'm still alive :P

Answer 1

In ogr2ogr you have dataset creation options, and layer creation options. According to http://www.gdal.org/drv_gpx.html, FORCE_GPX_TRACK=YES is a LAYER creation option.

So you have to add -lco "FORCE_GPX_TRACK=YES" to get the tracks instead of routes.

This works for the command line version just the same.

Make sure the data is in EPSG:4326.

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The above runs fine in the processing toolbox. You can look inside the logfile under C:\Users\<username>\.qgis2\processing\processing.log to see the executed command:

08:47:59|processing.runalg("gdalogr:convertformat","<input-shapefile>",16,"-lco FORCE_GPX_TRACK=YES","<output-gpxfile")

So I suggest to use gdalogr:convertformat instead of gdalogr:ogr2ogr. See http://docs.qgis.org/2.8/en/docs/user_manual/processing_algs/gdalogr/ogr_conversion.html#convert-format for the documentation, or processing.alghelp("gdalogr:convertformat").