Introducing KGeoTag, a KDE photo geotagging program

[Nicolas Fella]

Hi Tobias,

that looks like a neat application :) I'd say it's mature enough to
deserve a proper repository, so you can go ahead and ask sysadmins to
create one.

Cheers

Nico

On 17.10.20 20:54, Tobias Leupold wrote:
> Hi devel mailing list :-)
>
> I'm Tobias Leupold. I have been a KDE developer since 2014. I mostly
> participated in KPhotoAlbum. Currently, I'm one of the three active developers
> of the project (somewhat a jobbing developer, because I'm the only one not
> earning my money with writing code. I'm just a hobby programmer, but I try to
> do my best ;-)
>
> I'd like to introduce a new project I recently started. It's KGeoTag, a photo
> geotagging program for KDE. The code can be found on
> https://invent.kde.org/tleupold/kgeotag .
>
> At the latest since Digikam's geolocation KIPI plugin isn't available anymore,
> I think the Linux desktop lacks a decent geotagging program. There are a few
> programs able to write coordinates in Exif headers, but some aren't maintained
> anymore, some only do it besides and some are only graphical frontends to
> console programs without a real added value. At least -- speaking of me -- I
> didn't find a straightforward, nice geotagging program. I used GpsPrune
> recently, but it's written in Java, not nicely integrated with my desktop and
> it's inconvenient for geotagging. Mostly, it's lacking a simple drag-and-drop
> interface.
>
> As a KPA tenet is to not alter the images we cataloguize, I decided to write a
> small, overseeable new standalone program with the only purpose to geotag
> photos. And that's KGeoTag.
>
> Marble is used to display a OpenStreetMap map. One can load geodata from one
> or more GPX files which is drawn on the map. Images can be added and then
> assigned with coordinates in three ways:
>
> One can search for exact matches between the images' dates and available
> points from the GPX data, with a defined maximum deviation.
>
> If no exact data is available, interpolated matches can be calculated, with
> both a maximum timespan and distance between the points used for the
> interpolation.
>
> Finally, all coordinates can be set or corrected manually by dragging and
> dropping the images directly on the map. This is also possible without loaded
> geodata.
>
> Missing or incrorrect altitude values can be obtained from opentopodata.org's
> API. Either manually or automatically when dropping images on the map. This is
> disabled by default (for privacy reasons, as coordinates have to be
> transferred to opentopodata.org's servers when asking for a specific
> elevation).
>
> If there's a time drift in the images' metadata due to the camera's clock not
> being exactly in sync with the GPS data, it can be corrected and considered
> when searching for matches. Also, it can be fixed in the images' headers.
>
> Finally, the coordinates (and possibly fixed dates and times) can be written
> to the images. KGeoTag uses the libkexiv2 library with it's nicely geared-up
> geodata functions. Libkexiv2 being mature, well-tested and documented, I
> suppose we can be quite sure that KGeoTag doesn't eat the images it works on.
> Nevertheless, by default, a backup of the original files is created before
> saving the changes.
>
> I consider this project to be a complementary tool for KPhotoAlbum, and
> possibly other geodata-aware programs. It's purpose of application has tight
> limits, and consequently, the codebase is overseeable and should be easy to
> maintain.
>
> The code is quite new (still lacking even a 0.1 tag); anyhow, it's already
> fully functional. I successfully geotagged some real-life datasets of family
> vacation photos where I carried a GPS logger most of the time, and it worked
> nicely.
>
> Maybe, some of you also think that this would enrich the KDE ecosystem. I'd be
> happy to get some feedback. And perhaps, if I'm not the only one who thinks we
> need this, it could be moved to graphics/, like KPA? Surely, it's by far not
> important enough to be distributed by KDE like Marble or such, but maybe, it
> could be a KDE extragear application like KPA one day.
>
> Thanks to anybody having read the whole thing until here, and thanks in
> advance for all feedback :-)
>
> Cheers, Tobias
>
>