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Extract better GPS coordinates from images using exiftool

Sometimes I have to extract Exif information from images, mostly the GPS coordinates. The coordinates coming raw from the images are not very helpful. Let’s look at a picture I took today:


Enable and disable window dimming in KDE

When I make changes in OpenStreetMap, I often need to extract the object colour from a picture or a video, as example for a building, bench or a roof. This collides with a feature in KDE which I really like: Dim Inactive Windows.

The setting is in the KDE settings, under Desktop Effects -> Dim Inactive. As the name implies, it dims (makes them a bit more dark) all non-active windows - which makes it visually clear which window is currently active. Quite useful.

For picking a colour from a picture/video I’m using KColorChooser, which provides the colour in Hex code - exactly what I need in OSM.

However when KColorChooser is the active window, and all other windows are dimmed, it extracts the wrong colour from the picture/video - the colour which is already dimmed. Not what I need. Therefore when I do OSM edits, I temporarily disable this feature.


Find fire stations in OpenStreetMap using Overpass Turbo

My kid got a new project: find fire stations. Google Maps is not really helpful here, obviously. And searching in the OpenStreetMap web interface is also a lot of work. But Overpass Turbo is able to find all the places.

When you open the Overpass Turbo page, it starts in Rome, Italy, at the Colloseum. That’s nice, but likely not the place you are looking for. Either scroll to the area you are interested in, or use the search function.

The left side of Overpass Turbo is the input field. You draft queries in a specific language, named Overpass QL (QL). Once you hit the Run button, the right side of the window either shows you the map, or the data output.


OpenStreetMap: Find benches with missing access tag in JOSM

As reference for me: find benches with missing access tag in JOSM when editing OpenStreetMap:


OpenStreetMap: Find buildings with missing tags in JOSM

As reference for me: find buildings with missing tags in JOSM when editing OpenStreetMap:


Search objects based on a specific criteria (Key:name:etymology) in JOSM

This posting is mainly a reference for myself, because I was looking for this specific issue a couple times.

OpenStreetMap (OSM) is a map of the world, created by anyone who wants to contribute. It so happens that data might be missing (just go and add it, if you see that something is not on the map). It also happens that someone adds too much data.


Traveling in Cuba (offline)

In 2019 I was in Cuba for a conference that took place there.

During the preparation of the trip it occured to me that internet access in the country is on the one hand slow and not well developed. On the other hand, that mobile internet access via roaming is obscenely expensive. It was foreseeable that I would have to do without mobile internet for a week, and consequently without online navigation. Preparations are in order.

These preparations were divided into two areas: before the trip and during the trip. For a while I thought about buying a map (this paper thing that you hold in your hand), but outside of Cuba you can’t find good maps for tourists which you can buy in advance. And the available maps looked rather outdated, and without enough details. As a result, I scratched this option from the list.


Unterwegs auf Kuba (offline)

2019 war ich auf Kuba, für eine Konferenz welche dort stattgefunden hat.

Bei der Vorbereitung der Reise stellte sich heraus dass der Internetzugang im Land einerseits langsam ist, und nicht gut ausgebaut. Und andererseits dass der mobile Internetzugang über Roaming obszön teuer ist. Es war also abzusehen dass ich eine Woche ohne mobiles Internet auskommen muss, und demzufolge auch ohne online Navigation. Vorbereitungen waren notwendig.

Die Vorbereitungen teilten sich in zwei Bereiche: vor der Reise, und während der Reise. Kurz hatte ich überlegt ob ich eine Karte kaufe (dieses Ding aus Papier welches man in die Hand nimmt), aber es gibt außerhalb Kubas kein gutes Kartenmaterial für Touristen. Das was an Karten verfügbar war sah eher veraltet aus. Demzufolge habe ich diese Option wieder verworfen.


Geocaching in Cuba

Geocaching in Cuba is not very common, which may be due to limited Internet offerings, and the partially poorly developed infrastructure. Most caches exist in and around major cities and well-known resorts (Havana, Cayo Santa María, Guardalavaca, Cardenas, Pinar del Río). There are also some caches in and around Guantánamo Bay, but these can only be reached from the local Naval Base. Not for tourists …


Geocaching in Kuba

Geocaching in Kuba ist nicht sehr verbreitet, was vielleicht auch den Einschränkungen des Internetangebots sowie der teilweise schlecht ausgebauten Infrastruktur geschuldet sein dürfte. Die meisten Caches gibt es in und um einigen größeren Städten und bekannten Urlaubsgebieten (HavannaCayo Santa MaríaGuardalavacaCardenasPinar del Río). Weiterhin gibt es einige Caches in und um Guantánamo Bay, aber diese sind nur von der dortigen Naval Base aus zu erreichen. Also nichts für Urlauber …