Serious error: Time offset in exported tcx-files
jankoc opened this issue · comments
I have a problem with an offset in lat/lng-data compared to sensor data/elevation data when exporting from V800-downloader compared to Polar Flow. I have confirmed through testing that the data from Polar Flow is the correct one, so there is an error in the export when using V800-downloader.
The issue seems to occur when there is no lat/lng data for the first track points. E.g. if there are 12 track-points at the start of the tcx-file from Polar Flow without lat/lng-data, the first track-point in the export from V800-downloader gets the lat/lng-pair which actually belongs to the 13th track point. Correspondingly the second lat/lng in the export from V800-downloader gets the lat/lng-pair from the 14th track point, and so on. Thus there is an offset of 12 seconds in all sensor data.
Attached is an example.
I am still getting this problem for other cases. Could this problem come from Bipolar, or is it a V800 downloader problem?
Nobody else got this problem? Or is it not important to have HR in sync with GPS-data?
Hi @jankoc, are you able to provide the original data files that the v800_downloader exports? eg you could edit v800export.cpp commenting out the line:
QDir(QString(tr("%1/%2")).arg(default_dir).arg(multi_sessions[multi_sessions_iter])).removeRecursively();That will leave the data directory after the conversion, then zip/tar/gz/whatever that up and attach it here (if github lets you), otherwise email to git at colby dot id to au.
Cheers.
Unfortunately I haven't got access to a compiler environment. With the appropriate binary I'd happily do an export!
Oh, ok. I don't have official binaries for this project, just my own local build.
What OS are you using?
Windows (7)
... i just read about BIPOLAR, which is joined into v800_downloader (many thanks for it), that date are UTC .
indeed:
bipolar/test/polar/v2/schemata/gpx.xsd:179: Creation/modification timestamp for element. Date and time in are in Univeral Coordinated Time (UTC), not local time! Conforms to ISO 8601 specification for date/time representation. Fractional seconds are allowed for millisecond timing in tracklogs.
bipolar/CHANGELOG.md:42:- option to use UTC timestamps in TCX output (#36)
This is one point to check within your problem .