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During a long trip, I have recorded tracks of my journey with the GPS of my smartphone. I have ended up with about 30 GPX datafiles.

Now that I am back, I am trying to draw a map of this trip. I imported each file in QGIS as vector layer, and visualized the tracks with OpenLayers Plugin.

Now I need to edit some of these files:

  • basically trimming the end and beginning of many files
  • merging some tracks
  • adding a title or a description for each track

What is the way to do it with QGIS ?

I would like to keep as much data as possible from the source data (timestamp, elevation)

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    What kind of vector layer did you create for your tracks? You're going to lose timestamp/elevation from a line layer, but a collection of points (which would preserve those data) isn't going to display what you want. QGIS may not the right tool for this job. See here also. – Simbamangu Aug 13 '14 at 5:28
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    With my method, vector layers are created directely by importing the GPX data file (New Vector, From File, and selection of gpx: option tracks and tracks points). Elevation and time stamps seems to be conserved in the data table of attributes "associated" with the track points vector. – kFly Aug 13 '14 at 20:15
  • @Simbamangu, Thank you for link. I had already read your topic. How did you end up managing your database ? – kFly Aug 13 '14 at 20:21
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    Have a look at that other question - I've updated it with a solution for aggregating tracks. If I get time I'll write a longer response about managing them here! – Simbamangu Sep 1 '14 at 12:58
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I'm also searching for a really good way to do this... but in the meantime I do have a system which works OK. Slow but effective:

Use the Openstreetmap editor JOSM. This is good at displaying GPX info. Use the plugin 'InfoMode'. This makes it easy to see the time data on the GPX track. Note exact times for the nodes which you want to edit/delete etc. Edit the GPX file by hand in a text editor which is good at displaying XML files (or a specific XML editor of course).

Note that JOSM seems to take account of local time - so for me it shows times in UK summer time - whereas the GPX file has times in GMT/UTC.

Being able to use 'regular expressions' with the text editor helps if it turns out that your GPS has inserted additional useless information into the GPX (which you want to delete).

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I upvoted @user27285's answer. I don't know any better. I use the Josm editor with the EditGPx Plugin and other JOSM features to edit my gpx traces all the time. You can configure Josm to show when your track changed directions by color styles. On top of all those features you also have reference Imagery layers to pick from to help see where your data is located.

After loading a file, right click on the file name for a list of options.

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I Made a tutorial for my blog to help out with this. This uses the Garmin BaseCamp Software which is free to use. I cover how to join tracks, edit unwanted data out of tracks and how to reduce file size by filtering out unnecessary points. I hope this helps!

http://outdooroutlier.blogspot.com/2015/05/how-to-edit-gpx-data-to-make-useable.html

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Having previously answered this question (with the suggestion to use JOSM and a text editor) I think I now found a better answer.

Viking GPS editor seems to do a good job. I'm new to it and I'm testing it but so far I'm really pleased.

It works quite like GIS software with its ideas of layers and a basemap - but what's particularly pleasing is that it appears to work well with the GPX file structure/specification (rather than working in spite of it). So I don't see it (so far) messing around with adding silly extension tags to the file - instead working within the normal GPX specification. So if you work with a comment on a track it appears in the proper 'cmt' tags in the file for example. And it will show up the times and other data from the track waypoints... allow for joining and splitting of tracks, recognises track segments ('trkseg') and can work with these, and so on. And it'll work with photo geotagging/geotags too - so if you work with a smartphone or gps enabled camera it's simple to see everything in one place.

It may be useful to note that it opens GPX files by importing them - and saves by exporting. So you are left with the original file unscathed I think.

As a bonus it also works well 'out of the box' with various basemaps (e.g. OSM based basemaps) so there's no need to spend time setting up special mapping for this when you already have your GIS software set up for ordinary GIS work.

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I found a simple way to clean up GPS tracks: 1) load the points from the track in the GPX file (Add Vector Layer) and 2) join the points into polylines with the Points2One plugin. This solution is a little simpler than the others, can be done with just two QGIS tools, and there is no need to manually edit the GPX file.

Step 1 (as kFly mentions above): To open your GPX track, go to Add Vector Layer (in the menubar: Layer > Add Layer) and browse to your GPX file. See this video: https://www.youtube.com/watch?v=WWIh5Xjfix4 You'll get five options for what type of data to import: choose "Track Points". Each point will retain its timestamp and elevation in the attribute table. You'll have to save this as a shapefile to edit it (see the video in the link above). Turn on editing for this new file and remove all the junk points (at the beginning and end of the trip, for example). It is much easier to edit individual points than nodes within a single, large feature (what you get if you open the Track instead Track Points of the GPX).

Step 2: Use the Points2One plugin to convert the points into a polyline feature. This tool lets you create multiple features based on an attribute, so you could give all the points a common value in the attribute table and make multiple polyline features (for example: car route to trailhead, main hike route, side trip). The polyline features will retain the timestamp and elevation from the final point used to make the polyline. Hope this is helpful.

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The best solution I have found so far is : QLandkarte GT

It does all the actions I have listed and much more. The only trick is to get map overlay, but it is easier with the latest version.

It is worth to mention that it's multiplateform software.

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For the moment I managed to done some operations with gpsbabel and its filtering option.(see GpsBabel Manual).

I do not have the visualization of the tracks, but manage to do the merge, and trim (and you can automatize the work using scripts instead of editing each file individually)

I am still looking for a tool with visual feedback.


Edit 9/04/2014:
I gave a try to QLandkarteGT. It does pretty much all I wanted. The user interface is very friendly. And there is a lot of tracks analysis tools which are really handy to refine the work done wiht gpsbabel.

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