ddvo / gpxconv

GPX track converter to post-process tracks as typically produced by GPS loggers

GPXConv

GPX track converter: post-process routes and tracks typically produced by GPS loggers.

• Reads from file(s) given as argument (or STDIN) and writes to STDOUT or a file.
• Can append segments from multiple tracks and files (sequential composition).
• Can complete gaps in input file(s) by merging data from an alternative GPX file (parallel composition).
• Concatenates all given tracks (or routes) preserving segments, collecting waypoints.
• The metadata (header) of the first input track is used for the output track.
• Reports missing data and ignores points containing non-plausible data.
• Optionally filters out points before or after given time limits.
• Optionally filters out points with an element value below or above given limits.
• Optionally prunes all extensions or elements with value below or above given limits.
• Optionally fills in elevation and time data by interpolation within segments.
• Optionally interpolates points in long gaps (by default, > 3600 seconds).
• Optionally corrects elevation and sanitizes and smoothens tracks. (Orthometric height = GPS ellipsoidal height - geoid height, see http://www.unavco.org/edu_outreach/tutorial/geoidcorr.html)
• Produces statistics, optionally including ascent/descent rates of climbing phases.
• Optionally computes approx. total energy spent by biking along the resulting track.
• Prints information (if enabled), any warnings (if enabled), and errors to STDERR.

Usage:

  gpxconv <option(s) and infile(s)> [> <outfile>]

Command-line options:

  -walk, -cycle, -drive, -fly  - type of recorded activity, default: drive
  -smooth                      - smoothen tracks
  -phases                      - analyze ascent/descent phases
  -weight <value>              - compute biking energy for given weight in kg
  -begin <time>                - ignore points before given time
  -end <time>                  - ignore points after given time
  -max <name> <limit>          - ignore points with element value above limit
  -min <name> <limit>          - ignore points with element value below limit
  -max_ext <name> <limit>      - prune extension elements with value above limit
  -min_ext <name> <limit>      - prune extension elements with value below limit
  -prune_wpts                  - remove waypoints
  -prune_exts                  - remove track, waypoint, and trackpoint extensions
  -nw                          - do not print warnings
  -ni                          - do not print information
  -o <outfile>                 - output the resulting track to <outfile>

Other options can be set by changing values of the configuration variables.

gpxconv's Issues

Adding -swim option

Hi @DDvO,

I hope all is well! Open water swimming season has resumed and I have my first set of bad GPS points from my Apple Watch, so I wanted to follow up on a previous comment of yours:

If you provide me feedback/corrections to the following suggested limit data for swimming:

$MIN_TIMEDIFF          = 1;
$MAX_SENSIBLE_SPEED    = 10;
$MAX_SENSIBLE_ACCEL    = 1;
$MAX_SENSIBLE_ELE_GAIN = 1;
$MAX_SENSIBLE_ELE_LOSS = 1;

I can add the -swim option any time.

$MIN_TIMEDIFF = 1;

I think this makes sense. Most swimmers will be tracking GPS on a watch, so you'd only get a reading when the arm with the watch exits the water. Having said that, you can also just put a GPS device in a swim buoy and it would be able to get readings much more often. Some people tuck a watch under their cap.

$MAX_SENSIBLE_SPEED    = 10;

I just checked some results from a local race that took place today with some very good swimmers. The fastest time for a 1km race came in at 13:26. Based on that, I think $MAX_SENSIBLE_SPEED = 6; should be a sensible default.

$MAX_SENSIBLE_ACCEL    = 1;

I think this is good

$MAX_SENSIBLE_ELE_GAIN = 1;
$MAX_SENSIBLE_ELE_LOSS = 1;

I think those are both reasonable as well. I guess in theory you could be swimming up or downstream, but I think those are not the vast majority of cases.