Chaos Computer Club - archive feed

A deep dive into how StreetComplete stores edits and syncs them with OpenStreetMap, including persistence, solving conflicts and allowing users to revert their edits.

StreetComplete is known as an app to easily contribute selected data to OSM on the go.

The simple interface could make it appear that the technical implementation is equally simple. It is maybe a common misconception that things that look easy to the user are also lighter in terms of code complexity. But under the hood, it is anything but.

For example, amongst other things, the app has a unique way to avoid and to automatically resolve conflicts when uploading data to OSM. For an app that promises its users to work completely offline and thus automatically stores unsynced edits for any duration before upload, this is very useful to have.

Furthermore, it comes with the ability to undo edits in any order (not just the last) and even undo most edits after they have been synced with OSM already.

This talk shall give you an architectural overview over how StreetComplete enables its users to do these things.

It could serve other editor developers as inspiration, however, most technical concepts in this app are probably not well applicable to be used in a general OSM editor, as StreetComplete vastly limits its users what they can do and therefor we can make certain assumptions about how the app is used.

about this event: https://2021.stateofthemap.org/sessions/7M7WVX/

This track gathers various lightning talks of 5 minutes each.

## The Boundary Puzzle

*ark Arjun* | *[arkarjun](https://www.openstreetmap.org/user/arkarjun)*

The story of OSM Kerala community in developing the administrative boundaries of Kerala, a southern state of India. The Mammoth effort of volunteers made the different level of administrative boundaries of the state created a large impact in recent times including the pandemic management. The talk gives a brief on how the citizen-oriented participatory mapping revolutionised the open data culture and influenced the authorities.

## The YouTube community of OpenStreetMappers

*Gregory Marler* | *[LivingWithDragons](https://www.openstreetmap.org/user/LivingWithDragons)*

Let's take a look at YouTube and the community there from an OpenStreetMap view. I quickly cover the big and important channels that host talks, provide tutorials and learning, along with those doing desktop streams or turning on a camera and chatting as they go out mapping.

## Let's meet at an island. OpenStreetMap as a source for spatial chat tool worlds

*Helga Tauscher*

This talk shows how worlds for adhoc video-conferencing systems or spatial chat tools, for example [WorkAdventure](https://workadventu.re/) can be populated from geospatial or other real-world data on an automated basis. The island scenario is the first of three scenarios to be investigated, with the other two being scenarios on the building and city district level.

## Experiments in P2P tiles

*Iván Sánchez Ortega* | *[ivansanchez](https://www.openstreetmap.org/user/ivansanchez)*

An exploration on how a seemingly obscure web standard (WebRTC) can be exploited to provide P2P transmission of rendered map tiles and theoretically lower the load on the OSMF's tileservers.

## Open Healthcare Access Map

*Marcel Reinmuth* | *[maze2p0](https://www.openstreetmap.org/user/maze2p0)*

Get insights on travel time to healthcare facilities, population coverage and their interplay at different scales for a variety of countries. The [Open Healthcare Access Map](https://apps.heigit.org/healthcare_access/#/) is an OSM data powered application to explore health access.

## Bye Bye, Unclassified

*Martijn van Exel* | *[mvexel](https://www.openstreetmap.org/user/mvexel)*

Many words have been said and written about road classification in OSM. In this talk, Martijn van Exel will look at this topic through the lens of recent community initiatives in the United States, and add his own opinions you never asked for.

## Project OsmAPP.org

*Pavel Zbytovský* | *[zby-cz](https://www.openstreetmap.org/user/zby-cz)*

For a long time, I missed the single application for using OpenStreetMap. In this talk I would like to present the universal OpenStreetMap app, OsmAPP for short. After a few years of development, it already offers fast vector maps, clickable POIs, search and even basic editing capabilities. Let's hear the story of this project and discuss the future.

- Link: [osmapp.org](https://osmapp.org)

- Slides: [github.com/zbycz/osmapp-talk](https://github.com/zbycz/osmapp-talk)

about this event: https://2021.stateofthemap.org/sessions/ZLK9X9/

Turkish OpenStreetMap Community has constantly been growing with members from various circles in recent years however the community faces various problems such as insufficient OSM documentation and tools in Turkey and lack of learning materials in Turkish. Yercizenler and Youth Season NGOs kicked-off the Open Source Volunteering Programme to tackle community needs to build and enlarge OpenStreetMap Turkey community by training volunteers, translating OpenStreetMap related documentation/tools and mapping 120 unmapped towns in Turkey.

The Turkish OpenStreetMap Community has constantly been growing with members from various circles in recent years. It consists of participants such as hobby cartographers, academics, local governments, university student clubs and local NGOs. According to OSMstats, the community, which has an average of forty active mappers daily, has added more than 1.3 million buildings and more than 200,000 km of highways to the OpenStreetMap since 2018.

Active OpenStreetMap contributors identify community problems and needs are listed as following; language barrier and the inexperienced local community. According to the EF English Proficiency Index, Turkey ranked in 79 out of 100 countries/regions. Lack of having OSM documentation in Turkish is one of the biggest barriers to growing a mapping community in Turkey.

Insufficient OSM documentation in Turkish adversely affects participants of all levels. It causes a lack of technical knowledge about OpenStreetMap data structure among experienced mappers. Even if they make an outstanding amount of contribution, it can cause a decrease in data quality. From the newcomers' point of view, it significantly reduces the pace and motivation of learning.

In order to tackle these problems and needs, Yer Çizenler and Youth Season NGOs are teamed up and kicked off the Open Source Volunteering Programme. The main goal of this programme is building and enlarging the OpenStreetMap Turkey community. The objectives of this programme are to train volunteers to get to know more about OpenStreetMap, to translate OpenStreetMap related documentation and tools and to map unmapped towns in Turkey. This programme consists of three phases; training, translation of OSM tools and mapping unmapped towns in Turkey. 8 OpenStreetMap training, four mapathons, three online public experience sharing events and 18 weekly meetings were organized during the programme.

Twenty volunteers were selected to be part of the Open Source Volunteering Programme. These volunteers were trained on the following topics; fundamental of OpenStreetMap, OSM data model, OSM tag schema and OSM editing tools such as iD Editor, JOSM, Vespucci, GoMap! and RapiD. With the workshops and hands-on webinars, the participants got familiar with OSM data structure and gained the ability to use OSM editing tools. Additionally, the Open Source Volunteering Programme helped the Turkish OSM community to be connected with international OSM communities to learn from their experiences. As an example, we hosted Geoffrey Kateregga, Community Programs Manager at HOTOSM shared his learning and valuable community growth experience in Uganda as well as in Africa (1).

As the second phase of this program, the volunteers translated OSM iD Editor Vespucci, MapRoulette and uMap tools into the Turkish language.

In the third phase of the programme, volunteers mapped 120 unmapped towns in Turkey. Unmapped towns are exported from Pascal Neis's Unmapped Places of OpenStreetMap (2). These towns are mapped as points but do not have any roads in a radius of 700m. The MapRoulette and OpenStreetMap iD Editor are used to map unmapped towns. MapRoulette task was used to coordinate collaborative mapping efforts and monitor the progress (3). As a result, 11.838 map changes were made by 15 mappers. There are 10.295 unmapped towns in Turkey. As Yer Çizenler and Youth Season NGO, we're aiming to enlarge the active OpenStreetMap Turkey community and complete a map of unmapped towns in Turkey by the end of 2021.

Overall, this talk will highlight key elements of building and enlarging OpenStreetMap communities in developing countries and learnings from Open Source Volunteering Programme. The proof of concept of mapping unmapped towns methodology will be shared with other communities to encourage them to implement similar activities in their local community.

* (1) [https://www.youtube.com/watch?v=fD4fvmJ3Wmk](https://www.youtube.com/watch?v=fD4fvmJ3Wmk)

* (2) [https://resultmaps.neis-one.org/unmapped#5/47.100/9.800](https://resultmaps.neis-one.org/unmapped#5/47.100/9.800)

* (3) [https://maproulette.org/browse/challenges/15901](https://maproulette.org/browse/challenges/15901)

about this event: https://2021.stateofthemap.org/sessions/EHQ7GH/

We have developed an open source web app, OLMap, to take photos of entrances and map them in OSM and another one, Gatesolve, for delivery drivers to find the route to the right entrance based on this micromapped OSM data. Last year, over 6000 images including 5762 entrances, 1767 flights of steps, 645 barriers and 241 info boards were contributed to the 30000 entrances mapped in Helsinki, Finland. The mapping project will continue this summer.

True door-to-door navigation requires us to accept that people don't really visit housenumbers, they visit amenities and apartments via specific building entrances. The significance of this difference varies and is greatest in cities with unoptimal address schemes, for people with accessibility needs and for delivery drivers quickly visiting lots of unfamiliar recipients.

City of Helsinki in Finland uses OLMap to take photos of each entrance to a building, to correct the GPS location of the entrance, to record the address and other properties of the entrance as well as to facilitate mapping this information and the access paths in OSM. Last year, the city employed some secondary school students as mappers. Over 6000 images including 5762 entrances, 1767 flights of steps, 645 barriers and 241 info boards were contributed to the 30000 entrances mapped in Helsinki. A new batch of students will be employed this summer.

Using Gatesolve, delivery drivers can take advantage of the address, entrance, and accessibility data collected and mapped in OSM. To limit visual clutter, the app includes zoom-dependent cartography of the entrances. The search finds entrance-level addresses and the routing function visualises any steps and barriers on the way to the entrances.

An entrance typically doesn't have a unique housenumber, so it's important to also map tags such as "addr:unit", "addr:flats" or "ref" when appropriate. When these are not available, the different entrance types, access values etc. can help distinguish between entrances.

If a path without stairs has been mapped through to an entrance, we assume there are no stairs, but if there is any gap between the path and the entrance, we communicate uncertainty.

Entrances inside as opposed to along building outlines cause troubles for us. For example, there are entrances inside building passages and under hanging roofs. Mapping these entrances along "building:parts" can clarify this, but it's disproportionately laborous as well as prone to topological mistakes which result in inaccurate cartography.

We continue to develop the apps. For instance, all the mapping this far has been done in the iD editor, but custom mapping functionality may be necessary to feasibly support explicitly linking amenities to corresponding entrances via the proposed "associated_entrance" relations.

about this event: https://2021.stateofthemap.org/sessions/W7FP3J/

The mapping of access restrictions is often neglected, but access restrictions (and default assumptions about whether a path without any such information is usable or not) are important to make OSM safe to use.

OpenStreetMap has grown from a geeky niche project to a respectable data source powering a multitude of apps and web sites.

Our ethos is to “map reality”, and our approach is incremental – one person might trace something from aerial imagery, another person might add a street name from their own local knowledge, and a third person surveys and records a speed limit on a visit to the area.

Many paths, trails, and streets have access restrictions that may not be apparent from aerial imagery. These could range from oneway traffic rules to restrictions on certain types of vehicles, to “no dogs allowed”, or something could be entirely private, or in a military danger area.

End users of OpenStreetMap based services are often insufficiently informed about access restrictions, leading to a rising number of complaints from land owners or otherwise responsible individuals, and frequent requests to “immediately remove from OSM” a certain object. This can either be due to missing access restrictions in OSM, or due to existing access restrictions not being correctly interpreted by the platform using OSM data.

This talk intends to take stock of the current situation in OSM and major data-consuming apps, and make some recommendations aimed at both mappers and data consumers in order to reduce the risk of leading users down the wrong path.

The author is a member of OpenStreetMap’s Data Working Group which handles incoming complaints.

about this event: https://2021.stateofthemap.org/sessions/GEKXWL/

How to remotely map a city's public transport when due to the pandemic local trainings and community buildings are not possible.

Financed by the World Bank who wants to support the infrastructure of Mauritania and also the planning of the bus system, we from Trufi Association wanted to map the public transport of its capital Nouakchott. Our typical approach would be to train and empower local communities so that they can work with OpenStreetMap and public transport mapping in the long run, keep it updated, ensure ground truth, make it more sustainable. We would have made the mapping together and this way taught how to trace and upload bus lines, bus stops, and points of interest. The plan was to do this together with French organization “Les Libres Geographes” who are experts in this topic. Due to Corona, we were not allowed to enter the city and had to think of a plan B. We will show in this talk how a local team can do the collection of necessary data and how a remote team can do the mapping – organized by a regional partner who at least is nearby. We show how both sides could benefit nearly as much as if we had been there, and why this is in times of CO2 reduction and pandemic might be a wise choice for other cities and mapping projects as well. But we also show the limitations, for example that this would not have worked without a minimal preparation of the local people during the last years.

about this event: https://2021.stateofthemap.org/sessions/R3ZXY7/

Improving OSM data quality and coastal community resilience with the Map Quality Measurement workflow.

Over the past few years, the world has been experiencing the impacts of climate change with an increase in extreme weather events. Coastal communities are among the most vulnerable and face a range of unique flooding hazards including storm surge, wave impact, and erosion causing damage to homes, businesses, and infrastructure. Timely emergency response relies on high quality spatial datasets to support 911 calls, disaster planning, and response & recovery efforts. It is imperative that road network and water feature (ocean and inland) quality be as accurate as possible when used to support emergency operations. Our team has selected a few coastal cities to run a subset of relevant map error checks to identify the location and density of key errors that would impede response activities. With these data our team uses the Map Quality Measurement process to generate a heat map and narrow down the most problematic areas for communities to focus and improve data. 

Map Quality Measurement (MQM) is an analysis and visualization tool revealing the distribution of errors within a given geography. MQM works by running a series of checks, referred to as Atlas-checks, that identify geometric, topologic, and attribution errors. Atlas-check outputs show the density of data errors, the types of errors they are, and assign priority to critical fixes. The checks are written to review core map features such as roadways, buildings, waterways, coastlines, and their relationships with one another.

about this event: https://2021.stateofthemap.org/sessions/MXBCZY/

Over the past year, the Mapbox Data RAVE team has worked to improve data quality issues and engaged with various communities according to the Organized Editing Guidelines. The experience has been great and varied significantly from place to place. This talk will share the details and learnings for the community and other editing teams.

In October 2020, as part of on-going work to improve the quality of OpenStreetMap data, Mapbox Data RAVE employed osmlint-osmium and osmlint to detect road network data issues in Germany, France, Belgium, Netherlands, and the USA. We found significant issues that impact auto navigation, and variance depending on past editing activities of the community and corporate members in each country.

We began our work in each place in conversation. Sometimes we were met with friendliness, other times skepticism. We learned to respect local language conventions, which sometimes meant using machine translation, and this did help greatly. The preferred and active communication channels varied as well, from mailing lists, to forums, to IRC and Slack, to the Wiki and GitHub issues. For documentation, we took an “all of the above” approach, making sure to reflect adaptations in approach in all the spaces.

Technically we worked on 10 categories of mistakes: crossing highways, crossing highway bridges, impossible angle, island highways, impossible oneways, mixed layer and 4 categories connected with turn restrictions. We used all available ground truth sources to determine if an edit was needed, and tracked those edits with a changeset comments hashtags for our team and each country.

So far we have reviewed more than 26,000 issues and fixed almost 55% of them. Hoping that this is just the beginning of coordination with communities and the Data RAVE team.

about this event: https://2021.stateofthemap.org/sessions/RSLM3H/

about this event: https://c3voc.de

This track gathers various lightning talks of 5 minutes each.

## Building a Free Worldwide Long Distance Hiking Trail Map Together With OpenStreetMap

*Davey Lovin* | *[mDav](https://www.openstreetmap.org/user/mDav)*

Dozens if not hundreds of users worldwide have contributed a wealth of long-distance hiking trail information to OpenStreetMap. However, this data is difficult to extract in a meaningful and useful way and its quality varies greatly. This talk introduces [superroute](https://superroute.org/): an interactive webmap and quality assurance tool for OSM long distance hiking trails, with the goal of coalescing a community of passionate data-nerdy hikers to maintain and improve the data quality of these trails for the benefit of all.

## OpenStreetMap in the Philippines 2021

*OSM Philippines / Feye Andal* | *[feyeandal](https://www.openstreetmap.org/user/feyeandal)*

Last September 2020, the OSM-Philippines community released the [Call to Correct Narratives about Geospatial Work [in the Philippines]](https://wiki.openstreetmap.org/w/images/a/aa/A_Call_to_Correct_Narratives_about_Geospatial_Work.pdf). We’re provided with an opportunity to share our own narratives and showcase the local community’s initiatives through a documentary-video produced by Amazon Web Services – Philippines. We would like to share OUR story with the whole OSM community.

## Localizing Community Support through regional hubs.

*Geoffrey Kateregga* | *[Kateregga1](https://www.openstreetmap.org/user/Kateregga1)*

The Eastern and Southern Africa Open Mapping Hub will engage with local mapping communities, facilitate knowledge exchanges, distribute funding, and provide training and support in order to massively scale local edits to OpenStreetMap in 22 countries.

## Automatic building detection with ohsome2label and Tensorflow

*Hao Li* | *[leebob](https://www.openstreetmap.org/user/leebob)*

In this talk, we will introduce our recent work in detecting OpenStreetMap missing buildings and show you a walkthrough on how to train your own building detector using ohsome2label and the TensorFlow Object Detection API.

## ORS Tools - the QGIS Plugin for the openrouteservice

*Jakob Schnell* | *[ezelo](https://www.openstreetmap.org/user/ezelo)*

QGIS is great geoinformation software, the openrouteservice is a fantastic routing engine based on OSM data and this plugin brings them both together. Jakob Schnell from HeiGIT, one of the plugin maintainers, will give a short overview over the main functionalities of the plugin. Please talk to Marcel Reinmuth during the conference, since Jakob won't be able to attend :)

## OpenStreetMap in support of UN Peacekeeping missions: Unite Maps & UN Mappers

*Michael Montani* | *[Michael Montani](https://www.openstreetmap.org/user/Michael%20Montani)*

[Unite Maps](https://geoportal.un.org/arcgis/apps/sites/#/unitemaps), a program led by the United Nations Global Service Center, is leveraging OpenStreetMap data to deliver geoservices and cartographic products to UN Peacekeeping missions in Africa. The initiative supports peacekeepers in their operational efforts (as navigation and security) in areas torn by conflict. Unite Maps contributes to the extraction of OSM data as well as community support and capacity building of OSM communities under the umbrella of the UN Mappers network.

## Water and sanitation mapping in Nairobi's informal settlements.

*Peter Ageng'a* | *[Peter Agenga](https://www.openstreetmap.org/user/Peter%20Agenga)*

In this talk, we'll be sharing about the project that we conducted on mapping of water and sanitation in informal settlements of Nairobi through the support of OSMF under the 2020 microgrants projects. We'll be sharing some of the results and lessons learnt from the project and findings from a survey that we conducted on the impact of Covid on water and sanitation.

about this event: https://2021.stateofthemap.org/sessions/ZZ39T9/