[digiKam-users] Edit geolocation of pictures

[Steffen Hack]

Hi all,

 

i have some pictures without gps koordinates and would like to add them.

I always have Google Location Sharing enabled and so I just downloaded a kml file from http://google.de/maps/timeline of the concerning day and converted the file into gpx format.

Then I loaded the gpx file into the GPS Correlator of DigiKam, selected a picture and clicked on correlate.

But I always get the error message: „Could not correlate any image – please make sure the offset and gap settings are correct“

The gpx file contains a trackpoint with timestamp just a few seconds behind.

I tried several timezone, offset and gab settings but always the same message.

Anyone who could help me?

 

Mit freundlichen Grüßen,

Steffen Hack

PFALZ-COMPUTER

Bahnhofstr. 86

D-67454 Haßloch 

Telefon: [phone]

Mobil: [phone]

Fax: [phone]

[hidden email]

www.pfalz-computer.de

 

[Remco Viëtor]

On jeudi 22 août 2019 15:09:53 CEST Steffen Hack wrote:

> Hi all,
>
> i have some pictures without gps koordinates and would like to add them.
> I always have Google Location Sharing enabled and so I just downloaded a kml
> file from http://google.de/maps/timeline of the concerning day and
> converted the file into gpx format. Then I loaded the gpx file into the GPS
> Correlator of DigiKam, selected a picture and clicked on correlate. But I
> always get the error message: "Could not correlate any image - please make
> sure the offset and gap settings are correct" The gpx file contains a
> trackpoint with timestamp just a few seconds behind. I tried several
> timezone, offset and gab settings but always the same message. Anyone who
> could help me?

Not sure if this is any help, but I just got something similar. When I looked
at the gpx file (it's a simple XML format), the *dates* were wrong (don't ask
me how that happened, I have no idea). the *times* were correct... A simple
search&replace with the correct date fixed the problem.

Remco

[Steffen Hack]

Hi Remco and all others ;-)

date and time in the gpx file are correct and with another software (Geosetter) I can correlate some pictures. Only with DigiKam I get this error message.
But now I found another big problem:
The source files from Google Timeline (only KML format offered for download of a single day) does NOT contain timestamps for ALL trackpoints.
Only trackpoints that are PLACES contain timestamps. Most trackpoints only shown on google website when option "show raw data" is activated are NOT included at all and the other trackpoints that are not "places" do NOT contain timestamps (on google website they do, they are filtered out by Google when the KML file is created).
The only way to get all trackpoints from google (including raw data) is to download a JSON file at http://takeout.google.com but it's not possible for one single day but only the complete saved data.
So the JSON file is rather large (675 MB), starting in the year 2013 when I first activated position sharing.
I can open the JSON file with notepad or notepad++ (only x64 version because of the size). It's also a kind of XML and I can manually search for timestamps (Unix format in milliseconds) and see the latitude and longitude values.
Unfortunately it's a special google JSON format and NOT standard GeoJSON. So I found NO converter to GPX in internet (no working offline and no working online converter).
The only provider who let me upload a file of 675 MB was: https://mygeodata.cloud/converter/json-to-gpx but the JSON format was not recognized. They told me they are currently working on a converter for Google JSON format...
I found the starting timestamp of the concerning day in notepad++ and created a new smaller JSON file containing only that day. I just had to add the startig tag and the closing brackets at the end.
But I still cannot find any way to convert this file into GPX format.
Any idea?


Best regards / Mit freundlichen Grüßen,
Steffen Hack
PFALZ-COMPUTER
Bahnhofstr. 86
D-67454 Haßloch 
Telefon: [phone]
Mobil: [phone]
Fax: [phone]
[hidden email]
www.pfalz-computer.de

-----Ursprüngliche Nachricht-----
Von: Digikam-users <[hidden email]> Im Auftrag von Remco Viëtor
Gesendet: Freitag, 23. August 2019 19:58
An: digiKam - Home Manage your photographs as a professional with the power of open source <[hidden email]>
Betreff: Re: [digiKam-users] Edit geolocation of pictures

On jeudi 22 août 2019 15:09:53 CEST Steffen Hack wrote:

> Hi all,
>
> i have some pictures without gps koordinates and would like to add them.
> I always have Google Location Sharing enabled and so I just downloaded
> a kml file from http://google.de/maps/timeline of the concerning day
> and converted the file into gpx format. Then I loaded the gpx file
> into the GPS Correlator of DigiKam, selected a picture and clicked on
> correlate. But I always get the error message: "Could not correlate
> any image - please make sure the offset and gap settings are correct"
> The gpx file contains a trackpoint with timestamp just a few seconds
> behind. I tried several timezone, offset and gab settings but always
> the same message. Anyone who could help me?

Not sure if this is any help, but I just got something similar. When I looked at the gpx file (it's a simple XML format), the *dates* were wrong (don't ask me how that happened, I have no idea). the *times* were correct... A simple search&replace with the correct date fixed the problem.

Remco

Le 24/08/2019 à 08:12, Steffen Hack a écrit :

> I found the starting timestamp of the concerning day in notepad++ and created a new smaller JSON file containing only that day. I just had to add the startig tag and the closing brackets at the end.

if you can find the data with a text reader, you can certainly use a
script to extract them, may be if you give an example of the relevant
line (the one with the data) somebody could help you build one

jdd
--
http://dodin.org

[hajo]

On Sat, Aug 24, 2019 at 2:20 PM [hidden email] <[hidden email]> wrote:

Le 24/08/2019 à 08:12, Steffen Hack a écrit :

> I found the starting timestamp of the concerning day in notepad++ and created a new smaller JSON file containing only that day. I just had to add the startig tag and the closing brackets at the end.

if you can find the data with a text reader, you can certainly use a
script to extract them, may be if you give an example of the relevant
line (the one with the data) somebody could help you build one

Maybe start with GPSBabel? That usually solves a lot of GPS track/route conversion problems.

[Martin Burnicki-2]

Sorry, I just came across this older message.

Remco Viëtor wrote:
> Not sure if this is any help, but I just got something similar. When I looked
> at the gpx file (it's a simple XML format), the *dates* were wrong (don't ask
> me how that happened, I have no idea). the *times* were correct... A simple
> search&replace with the correct date fixed the problem.

This is due to a GPS week number rollover, which happened on April 6/7
this year.

Some GPS devices can't handle this correctly and step the time back by
1024 weeks, which results in a date in 1999. See:
https://kb.meinbergglobal.com/kb/time_sync/gnss_systems/gps_week_number_rollover

Other GPS receivers have implemented a very simple approach to "adjust"
the week number they receive from the satellites. This approach can fail
at any weekend, depending on the receiver and firmware. See:
https://kb.meinbergglobal.com/kb/time_sync/gnss_systems/gps_week_number_rollover#a_simple_error_prone_approach

I have an old GPS tracker, based on a MediaTek chip, which still outputs
the correct dat:
https://www.amazon.de/gp/product/B002V182KG

And I have another one which is newer, but fails and outputs the wrong
date now:
https://www.amazon.de/gp/product/B00I4Z1SQS

I use gpsbabel
https://github.com/gpsbabel/gpsbabel

on a Linux command line to retrieve the data from the GPS trackers and
store the tracks in GPX files. Current versions of gpsbabel provide a
command line option to shift the date saved in the gpx file by 1024
weeks (i.e., by 7168 days), so the dates in the gpx file are correct. See:
https://github.com/gpsbabel/gpsbabel/issues/349#issuecomment-526851146

Martin