This blog post is part of a series of blog posts about the new OSM file format “OMA”. This is the third post. At the end of the article you’ll find links to the other blog entries.

 

Until now you’ve got a general idea of what the Oma file format is, and an idea of how to use it. But you do not know, where to get an Oma file from.

Well, I hope, that sooner or later someone like Geofabrik will provide a daily updated planet.oma and some excerpts. That would make sense, because converting the data takes a lot of resources, and it would be a waste if everyone had to do it themselves.

But until we have such a distributor, you have to convert OSM files to Oma files on yourself. I have written a converter for this purpose. It’s written in Java and should be easy to use.

 

The Converter

You need a copy of oma.jar. If your are using Linux (or any other Unix operating system) you just have to type the following command:¹

java -Xmx<some number>G -jar oma.jar <some osm file>

The -Xmx part tells the Java Virtual Machine to use <some number> gigabytes of memory. For example, my computer has got 4GB of main memory, so I’ll use -Xmx3G, reducing the available memory by 1GB, because the operating system needs some memory too.

The osm file mentioned in the command, can be one of .osm, .o5m or .pbf².

Well, that’s about it. The program will read the file and start the conversion. This can take a long time, and hopefully it won’t crash.

Huh, crash? I wish I could give you better news, but unfortunately I have not been able to write a program that does never crash. The reason for this is that Java gives no guarantees or means of dealing with out-of-memory situations.³ So: If you have enough memory (and disk space), a crash should never happen, but if you have only limited memory, a crash might be possible.⁴

… See full entry

– Read in English

Acessando informações em momentos de crise - Entrevista com a Dra. Raquel Dezidério Souto, sobre o desastre do Rio Grande do Sul (Brasil), ocorrido em abril e maio de 2024.

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Esta entrevista está registrada no Zenodo.org e disponível como arquivo PDF. Como citar esta entrevista:

Acessando informações em momentos de crise: entrevista com a Dra. Raquel Dezidério Souto, sobre o desastre do Rio Grande do Sul (Brasil), ocorrido em abril e maio de 2024. Entrevistada: Raquel Dezidério Souto. Entrevistadora: Laura Bortoloni. Rio de Janeiro: IVIDES.org, 20 mar.2025. DOI: https://doi.org/10.5281/zenodo.15058822. Licenciado sob CC-BY-NC-ND 4.0 Ⓒ autoras.

Esta entrevista está disponível também em Inglês: https://doi.org/10.5281/zenodo.15058928

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1. Perfil profissional

Você pode nos contar sobre o seu background e como se envolveu com a cartografia?

Meu primeiro contato com a cartografia foi na graduação em oceanografia. Depois, no mestrado em Estudos Populacionais e Pesquisas Sociais (IBGE) e no doutorado em geografia (UFRJ). Ao longo do tempo, desenvolvi linhas de pesquisa em mapeamento colaborativo, com apoio de cartografia digital e mapeamento Web. O foco do meu pós-doutorado em geografia tem sido o desenvolvimento de soluções Web para mapeamento colaborativo digital. Atualmente, desenvolvemos projetos com software livre ou projetos híbridos (misturando software livre e proprietário), no âmbito do Instituto Virtual para o Desenvolvimento Sustentável - IVIDES.orgⓇ, instituto virtual de pesquisas que criei em 2008; alguns desses projetos, sendo viabilizados pela IVIDES DATA, sua empresa gestora.

O que a atraiu para a cartografia humanitária e para os projetos de cartografia participativa?

… See full entry

– Ler em Português

An interview with a university in Italy gives details of the collaborative mapping carried out in response to the Rio Grande do Sul disaster

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This interview is registered on Zenodo.org and available as PDF file. How to cite this interview:

Accessing information in moments of crisis - Interview with Dr. Raquel Dezidério Souto about the Rio Grande do Sul (Brazil)’s disaster occurred in April and May, 2024. Respondent: Raquel Dezidério Souto. Interviewer: Laura Bortoloni. Rio de Janeiro: IVIDES.org, 20 mar. 2025. DOI: https://doi.org/10.5281/zenodo.15058928. Licensed under the CC-BY-NC-ND 4.0 Ⓒ authors.

This interview is also available in Portuguese:* https://doi.org/10.5281/zenodo.15058822

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1. Professional Profile

Can you tell us about your background and how you became involved in Cartography?

My first contact with cartography was during my undergraduate studies in Oceanography. Then I got my Master Science in Population Studies and Social Research (IBGE) and my PhD in Geography (UFRJ). Over time, I developed lines of research in collaborative mapping, with the support of digital cartography and Web mapping. The focus of my post-doctorate in geography has been the development of Web solutions for digital collaborative mapping. We are currently developing projects with free software or hybrid projects (mixing free and proprietary software), within the framework of the Virtual Institute for Sustainable Development - IVIDES.orgⓇ, a virtual research institute that I created in 2008. Some of these projects are being made possible by IVIDES DATA, its management company.

What drew you to humanitarian mapping and participatory mapping projects?

… See full entry

Headed to Dutchess County in NY to update a smaller commercial Area. Added the parking lots, turn lanes, and buildings for the commercial areas that were missing. Still a lot of details to go.

and a detail shot

… See full entry

I maintain a web map style that shows walking and cycling route names. For the cycle routes, it shows the ref. For some time I’ve massaged some of the names so that e.g. National Byway loops show as “NB (loop)” just like on the signage. However, as can be seen from the example above, some hiking route names are a bit convoluted - they’re more like descriptions than names.

For example, osm.org/relation/3971851 is the England Coast Path. Open up the list of members to see the names, which includes such delights as “King Charles III England Coast Path: Southend-on-Sea to Wallasea Island”. I’m pretty sure that it doesn’t say that on the signs there.

… See full entry

Import dans Openstreetmap des espaces de stationnement de vélos et trottinettes électriques en free floating de la MEL

Contexte

La MEL a depuis mars 2024 lancé un appel à projet (s’inscrivant dans l’Action 34 du Plan de mobilité horizon 2035 ), auquel Lime et auparavant Tier ont répondu pour déployer une flotte de VAE (vélo à assistance électrique ) et de TE (trottinette électrique) sur les communes qui le souhaitent. 68 communes ont répondu favorablement au déploiement du service sur leur territoire.

La détermination des espaces de stationnement se fait de la manière suivante : - Propositions d’emplacements faites aux communes par la MEL au regard de critères d’attractivité, de maillage du territoire, d’occupation de l’espace public. - Avis des communes sur les localisations. - Formalisation des emplacements exacts inscrits dans les arrêtés municipaux d’occupation temporaire du domaine public. - Travaux de marquages au sol réalisés par la MEL après réception des arrêtés municipaux et conformément à ceux-ci.

Précision de la données

Les données de ces espaces de stationnement ont été publié en Opendata en juillet 2024 :

https://data.lillemetropole.fr/geonetwork/srv/fre/catalog.search#/metadata/3b58eafd-19c5-404c-ad90-ed4035535fc7

Le point est normalement précis, il peut y avoir quelques décalages lorsque la station est masquée par un obstacle (arbres, préau) ou lorsque l’entreprise de marquage a décalé son emplacement prévu lors de l’opération de marquage.

Après vérification avec des points connus et l’ortho photo de l’IGN, les points sont assez précis ; après croisement avec les bâtiments, seuls 2 points sur 1300 ont dû être décalé de quelques mètres.

Au total, 1387 espace de stationnement ont été définis.

Les attributs sont également bien renseigné et exhaustif sur l’ensemble du jeux, le champs type_engin permet de distinguer les espaces dédiés au seul VAE et ceux dédié au TE et VAE.

Quels tags choisir ?

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جسم

تخييم

اماكن تخييم

اماكن مراعي اغنام

There’s a saying in a certain article on the OpenStreetMap wiki that “tagging for the renderer” is equivalent to “lying to the renderer.”

Not only that, but the article also restricts the definition and meaning of “tagging for the renderer” as “the bad practice of using incorrect tags for a map feature so that they show up in the mapper’s renderer of choice. Such tagging goes against the basic good practice principles.”

I think that “tagging for the renderer” as a term should first be treated as neutral. On its own, there is no implication that “tagging for the renderer” forces us to lie to the system. Sometimes, people want to do tagging for the renderer simply because they want to place cool symbols around their area in OSM Carto.

Take me, for example.

Several months ago, I decided to download the entire openstreetmap-carto GitHub repository to analyze all of the (cool) icons contained within it and determine which tag combinations were needed to summon such icons on the OSM default map tile.

I found that the charging station icon was really cool. I loved its light blue color scheme, and its visibility on the map tile was quite good—it was already displayed at zoom level 17, on par with bank, gallery, and embassy icons.

I wanted to place this icon around my neighborhood soon. But alas, I didn’t know where any charging stations were located. So I shelved this idea for weeks and months.

Then, during a work trip to Bandung, while walking past the campus I attended as a student several years ago, I finally saw one. A charging station in the wild! It was stationed right in front of the parking area of the Labtek V building.

I was so elated—it felt like finding a legendary Pokémon in the wild! At that moment, I immediately stopped walking, opened Vespucci, and mapped the charging station.

… See full entry

UMBRAOSM Brazilian Openstreetmap Mappers Union provides several video classes on its YouTube channel. Access our content and enjoy mapping!

Video lessons for mapping objects in OpenStreetMap.

How to map buildings using the Buildings_Tools plugin in the Josm Editor

https://www.youtube.com/watch?v=nVPdf9MjvjQ

How to map a neighborhood boundary in OpenStreetMap with a custom background layer.

https://www.youtube.com/watch?v=sTe-1N2QvLY&t=2s

How to map in OpenStreetMap with the help of Mapillary images using the ID editor.

https://www.youtube.com/watch?v=dmDW5LhfQpk&t=52s

How to customize the colored painting style to offset street names in the JOSM Editor.

https://www.youtube.com/watch?v=4jOnFjtuI10&t=57s

Enabling remote control and expert mode in the JOSM editor

https://www.youtube.com/watch?v=H8qL_l18f7c

… See full entry

Con motivo del Open Data Day de este año invité a diferentes instituciones educativas de la Comarca Lagunera para recibir talleres de mapeo básico entre el 1 y el 7 de marzo.

El taller “Mapeando tu escuela” lo impartí en:

• Universidad Autónoma de la Laguna, el 5 de Marzo.
• Universidad Tecnológica de La Laguna Durango, el 7 de Marzo.

Espero más universidades se sumen a este evento el siguiente año.

مياه

سكن رعوي

صفيح زيقوا

En un reciente análisis publicado en mi blog, exploré la distribución de piscinas en Santa Cruz de la Sierra utilizando datos de OpenStreetMap. La hipótesis detrás del estudio es que la presencia de piscinas privadas puede ser un indicador del nivel socioeconómico de una zona, considerando los costos asociados a su construcción y mantenimiento. Puedes leer más sobre esto en el artículo completo aquí: ¿Dónde están las piscinas?

Previo al análisis, dediqué aproximadamente tres semanas a mapear alrededor de xxxx piscinas en el área metropolitana de la ciudad, utilizando JOSM para la edición de datos. Este esfuerzo fue clave para mejorar la cobertura de OSM en la región y asegurar que la base de datos reflejara con mayor precisión la distribución real de estas infraestructuras. Durante este proceso, utilicé imágenes satelitales (Imágenes aéreas de ESRI mundial).

… See full entry

مناطق رعوية قديمة

25/3/15-25/3/16 高野山の光明院という宿坊にて開発合宿を決行。

Please note: This blog post is part of a series of blog posts about the new OSM file format “OMA”. This is the second post. At the end of the article you’ll find links to the other blog entries.

 

This time I will give you an example of how to query Oma files. I wrote a prototype of a library for working with Oma files. I called it OmaLibJava.

To explain how to use this library, let’s say, we want to create an overview map of all the power facilities in a certain town.

 

The Classical Approach

The classical approach with OSM files would be, to first reduce the size of the file by creating a smaller file containing only the data of interest. This is typically done in two steps: remove everything that is not a power facility / remove everything that is not in the town. The order of these two steps is not important for the result, but might have a huge impact on the duration of the process.

Although it is not necessary – or even counterproductive – this can easily be done with Oma files too. For example, the following small Java program extracts all power facilities of Germany:

import java.io.*;
import de.kumakyoo.omalibjava.*;

public class ExtractPower
{
    public static void main(String[] args) throws IOException
    {
        Extractor e = new Extractor("germany.oma");
        e.addExtract(new BlockFilter("power"),"power.oma");
        e.run();
    }
}

Running this program on germany.oma on my computer takes 8.5 seconds. It creates the file power.oma, which is about 22MB in size and contains all power facilities of Germany.¹

Let’s have a closer look at the program: the library contains a class called Extractor, which reads an Oma file (here germany.oma) and writes several extracts simultaneously (here only one, called power.oma).

An important part is the filter BlockFilter("power"). This tells the extractor to keep only elements with the key power. I’ll tell you more on filters in a moment. But first I want to show you why you don’t need this step.

 

… See full entry