Elevation wrong

[Rindo]

Hello, I am using OsmAnd since 3 years, and I like this tool very much

... except for an issue I have since several months :

when recording a track, the elevation records includes many spikes, 

and the resulting cumulatinve elevation, up and down, is totally wrong. 

I have the latest version of OsmAnd. My smartphone is Xiaomi redmi 8pro

Thank you for your advise and directions

[Dmytro Prodchenko]

Hello! Thank you for the feedback. 

The latest release version of OsmAnd is use Google Play services to determine the location. We have feedback about issues with altitude, we made changes and in the next release would be available to select Android API as the location source.

If your device doesn't have Google Play services, you can try to install or update them. Also, you can try to download the nightly build, and test track recording with Android API as a location source https://download.osmand.net/latest-night-build/OsmAnd-default.apk, you can find the needed option in Menu – Settings – OsmAnd settings – Location source.

[Rindo]

Thank you so much Dymtro for your clear and detailed answer about the issue and the solution options !

I will not touch the Google Play Services, as this is uptodate. I have installed the night build and I will check the result in practice.

If not okay, I will revert back to the previous version  of OsmAnd, while next version will be released.

Once more, thank you for your fast and clear support.

[Rindo]

Hello, 

I have tried the proposed solutions to resolve the altitude error, without success. 

I have tried, one at a time, with : installing the night build release, installing last year release, reinstalling google play services. 

I am still getting very large cumulative elevation errors, i. e. 350 mt iso 50 mt, or 1200 mt iso 350 mt. 

Do you have other suggested solutions to resolve this issue ? 

Thanks, Rinaldo

[Greg Troxel]

Rindo <rind...@gmail.com> writes:

> I have tried the proposed solutions to resolve the altitude error, without
> success.
> I have tried, one at a time, with : installing the night build release,
> installing last year release, reinstalling google play services.
> I am still getting very large cumulative elevation errors, i. e. 350 mt iso
> 50 mt, or 1200 mt iso 350 mt.
> Do you have other suggested solutions to resolve this issue ?

There are a lot of variables: Android API vs proprietary Google Play
API, and various phones may have bugs. Plus, elevation in the Android
API is defined as height above ellipsoid (HAE), which is not what people
think of as elevation -- they generally want to see orthometric height
(very roughly, above some sort of mean sea level).

I recommend running GPSTest, which will show HAE and orthometric height
using the Android API. It shows HAE, mislabeled Alt, and "WGS84
orthometric height", labeled not really wrong as "Alt (MSL)".

Depending on where you are these will be different. But certianly not
by 800m, and even 300m seems beyond the actual range. Around me,
northeast US, orthometric heights values are 29m higher than HAE.

(There is also MyLocation, useful for understanding network location
providers, but it does not show elevation.)

GPSTest is available on F-Droid. I am unfamiliar with the Google Play
version.

[Rindo]

Thank you Greg for your review and input. I think that I expressed myself incorrectly. My issue is not the altitude value. The issue I have is the cumulative elevation I get from OsmAnd.

I have installed GPS Test. I get the same altitude as with OsmAnd. See attached.

But when I do a walk and record, I get the cumulative elevation totally wrong. See attached.

I hope this clarifies my issue.

[Dmytro Prodchenko]

You can try to download "World altitude correction" from the Download Maps, but it only affects current altitude data.

If you see spikes on the altitude graph, that result in wrong data in Uphill/Downhill fields, you can try to filter out those spikes by using a GPS filter, you can find it in the track context menu > options.

[Rindo]

Thank you Dmytro for your input ! I see indeed spikes on the altitude graph.

See atteached the same track recorded with OsmAnd (red) and another tool (blu), with the same smartphone. Attached are also the original gpx files I have compared.

I am reluctant to filter the track with the GPS filter, as this is just removing points from a specific track, and not solving the basic issue.

I am confused on why the GPS elevation is correct on another application, while with OsmAnd I am getting spikes.

[Greg Troxel]

I wonder if OsmAnd is using Google Play location and the other app the
Android API, or the other way around. It would nice to have a
diagnostic app that records both.

[Rindo]

This is right. The issue with the altitude is based on the way that

OsmAnd gets the altitude from Google play services, as was initially

notifief by Dmytro. 

Also, this seems to be a known issue, dependent on the smartphone type.

See link : 

https://github.com/osmandapp/OsmAnd/issues/10864

Well, I hope that next release of OsmAnd will move to Android API

and resolve my issue. 

[Dmytro Prodchenko]

The current beta version allows choosing "Location source" between "Android API" or "Google Play services".

OsmAnd beta https://play.google.com/apps/testing/net.osmand 

OsmAnd+ beta https://play.google.com/apps/testing/net.osmand.plus 

[Rindo]

Great ! Thanks Dmytro for the directions. 

I will install the current beta today and will try it in the next few days. 

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