Re: gpsfilter that offsets or randomizes positions?

[Gary E. Miller]

Yo Jens!

On Mon, 10 Feb 2025 18:38:01 +0100
Jens Scheidtmann <jens.scheidtmann@gmail.com> wrote:

> do you know of a tool that takes the dump gps datagrams from gpsmon
> and offsets the positions by a random amount (fixed per invocation)?
> Such as

No.  And gpsmon is unmaintined, unsupported and deprecated.

> I am asking for the following use case:
> I would like to have users submit gps dumps of their devices and
> construct test cases from that, that I'd like to check into github.

You can do whatever you want, but the undocumented edge cases of
GNSS recevier output are legion.  "Adjusting" gpsd output to get
valid output will be very difficult.

> Their home locations will be personal identifyable infomation in the
> worst case (I am in Europe and want to play it GDPR safe).

Many people try to obfuscate the data they send us.  Almost all
fail to truly obfuscate their real location.  Tell people to take a
day in the park and gather data there.  If they feel the need to
feel like James Bond.

> Are you aware of such a tool?

No, several have tried.

> If it needs to be built, what are your recommendations?

Well, I don't need it, but maybe you do, so have at it.  What
possible use could that data be?

I would take the JSON out of gpspipe, and mutate that:

gpspipe -w | gpsrandom > random.js

But, at least to me, that random.js is useless.

RGDS
GARY
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Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
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