Trimming waypoints from a GPX or TCX file?

[WilliamTM]

I have a collection of 450 TCX files from a Garmin GPS unit, which contain both the routes and heartrate/cadence data from various bike rides, which a friend of mine has done over the past few years.

 

I want to turn these TCX files into GPX files (so the heartrate/cadence data isn't needed), so I can create a giant map of everywhere that's been ridden. I've done this before with my own rides, and around 270 rides (from 270 gpx files), merged into one GPX file, resulted in a 31MB file which Google Maps can handle perfectly.

 

Now, I can convert two and from TCX and GPX, and merge GPX files and so on, using GPSBabel, but my problem is this: All the TCX files I have total 700MB in size, and have way too many waypoints than are necessary - and with about 20 rides merged into one GPX file, if I open that in Google Earth it is unbelievable slow, so if I do that with 450 rides it'll be unbearable.

 

So what I want is a desktop-based app that I can feed either GPX or TCX files which can "trim" the waypoints to whatever is necessary. Does a program like this exist? The closest I've found is this site: http://www.coursemapper.com/coursecompacter.htm - but it can only work on a single file at a time, which you have to upload - so if I do it that way, it's going to take a heck of a long time. However, it does do the job perfectly - if I feed it a TCX file with 1500 waypoints, it reduces that to around 400 and the map still looks almost perfect.

 

Any ideas?

[robertlipe]

Use gpsbabel's poly line simplification and nuke type filters to reduce the data sets.