Diary Entries in English

Recent diary entries

Wheelchair access

Posted by Gazgez on 22 June 2016 in English (English)

Changed a wheelchair = yes to no following a visit. Access is via four stairs or via moving furniture on a restaurant forecourt. is a new evil (instead of Potlatch)?

Posted by BushmanK on 21 June 2016 in English (English)

Some people were quite excited about recent announcement of built-in OSM editor of navigation app, but now, first version of it is in use for many weeks, bringing up more and more complains about users doing all kinds of unwanted things.

Since pointing on negative facts makes certain people feel offended, I want to clearly explain my position. I agree, that OSM could have more contribution from people, not deeply involved in project. And general idea of enabling them to do such contribution using their favorite navigation app is close to perfect. is the first widely used app helping its users to contribute to OSM. This app does have certain nice features such as opening hours entry. I also realize, that it's only the first version.

However, there are certain flaws, making its future look not that optimistic (at least - in given current situation). I don't want to try arranging these flaws by its importance, but I'd like to list some.

One fundamental flaw is that authors of this app don't seem to care about demotivating effect of "rubbish edits". There is common mantra: "We need more OSM contributors". Yes, it's true, but only in certain ideal case, where new OSM members are at least thorough and responsible. I mean, if some newbie doesn't know how to do something right, he should learn it after being pointed on documentation or receiving some explanations in changeset comments/private messages. If he doesn't want to improve his quality of contribution, all responsibility for data quality gets automatically shifted to responsible OSM members overseeing particular territory. They have to fix every mistake to keep data tidy. And they have limited amount of time, good will and energy to work on OSM. Forcing them to take care about unusually large amount of bad data (including investigations using WhoDidIt, achavi and other tools) simply reduces amount of contribution they making. Keeping in mind huge difference between their productivity and productivity of general newbie, it's not an equivalent exchange, because single amenity, wrongly added by a newbie, steals time, enough for much larger contribution made by experienced person. I call it general fundamental flaw in attitude of authors towards the whole OSM community.

Another flaw is that hosting on GitHub currently seems more like a gesture. I'm not talking about code, I'm talking about interaction with community. @Zverik, as a member of development team, has confirmed, that they have internal bug tracker, completely separate from GitHub, and that developers rarely checking GitHub issue tracker, however, they are reading bug reports, sent to dedicated email address. This situation makes it look like developers are non-responsive. It could be not completely true, but since there is no reaction from their side on GitHub, it's not unreasonable to conclude that.

Recently, an interview with one of authors was published, and it sounds like major ideologists are going to leave this project in favor of own startup. Which probably means, that less people will actually work on development planning. I don't believe, that it will improve responsiveness of the whole team.

I know very well, how sensitive authors can be, when it comes to critical feedback from users. But if you can't treat it as useful feedback, that job isn't for you - development is not a kind of comfortable place for sensitive unrecognized genius. Indeed, angry OSM members, tired of cleaning after users, could be pretty impolite, but at least certain comments contain useful suggestions such as, for example, separating editor workflow into it's own portion of UI. However, @Zverik recently called all those comments "non-constructive whining". It's typical, and it always leads to greater separation of developers from users. In psychology, it's called "avoidant behavior". I don't know, if it's just his thing or working style of the whole team, but anyway.

From the point of view of UX, there is an issue with built-in OSM editor. Users of, except ones who already knew about OSM or who learned about it independently, usually have no idea what exactly they doing when editing the map. Automatically, they have no idea about project guidelines and so on. As I've already mentioned once, you can't make people edit OSM without telling them what it is. But now, they are a kind of lured into doing that. Therefore, their ideas of what they actually doing are often quite imaginary. Judging by many different edits, it's easy to conclude, that people thinking that it's just their local copy of map, or those edits are some kind of bug reports for professional mapping team, or these are just their own custom POIs. User interface provokes it even more.

Since UI/UX provoking systematic wrong edits of certain specific types, it must be fixed instead of blaming OSM members for their "lack of patience". Leave aside real programming bugs, such as breaking opening hours in certain complex situations, replacing "№" sign with "N" and many others (including ones, left without any response on GitHub issue tracker).

My personal view on this (and I've expressed it long time before the very first version of MapsWithMe/ is that only way to allow people, who have no idea about OSM, to contribute is to limit available actions even more and to introduce more checks (such as duplicate check). It is way more complex problem than just development of an editor, since larger coverage of people, completely unaware of OSM, obviously brings more problems to solve before it will become effective and not demotivating for OSM members.

The invalid areas of the map

Posted by PlaneMad on 21 June 2016 in English (English)

There is some interesting research on the validity of polygons/area features mapped on OSM by Jochen Topf the creator of the osmium suite of OSM processing tools. There seems to be two major problems:

  • There exists multipolygons in OSM that have the old style tagging, with the tags on the outer way, rather than the relation
  • Polygons or multipolygons with a gemotry that is invalid, the most problematic being an unclosed area

In his usual style, there exists an in-depth explanation of the problem. Bonus is a chapter on OSM polygons and how they are rendered for GIS nerds.

Of the over 220 million (multi)polygons in OSM more than 100,000 contain mapping errors of one kind or another and about 250,000 are tagged old style with tags on the outer ways instead of on the relation making multipolygon tagging and processing much more complicated and much more expensive than it needs to be. Read more

I dug into the dump of invalid polygons and inspected it in QGIS to get an idea of the breakup of issues to see if they can be prioritized to fix:

By node count of area

There are 2500 invalid areas with over 50,000 nodes, so these are some very very large issues.

By issue type

82% of issues are role mismatches. For eg. an outer area inside an outer area, or vice versa. The next biggest issues are duplicate members or self intersection. Other issues are less than 2%.

Here is a map of all the issues. Just click on any one and you should be able to open it in JOSM for a closer look:

Fixing them

I tried to dig a deeper into each type of issue to understand the problem and get a sense of how it could be fixed. Feel free to explore and post your findings as well.

Role should be outer or inner

Might require manual cleanup based on context

Way Intersections

Requires manual cleanup - trivial. Requires shifting the problematic node by a small distance in the right direction to clear the error. - screenshot 2016-06-07 19 33 40

Touching ring

Requires manual cleanup - trivial. Requires ungluing the touching node and handling like a duplicated node - untitled2

Relation Intersection

Requires manual cleanup - Not trivial. Needs careful modification of relation geometry and roles if multiple segments are involved. Trivial if on the same segment just like way intersection.

Inner with same tags

Could be auto cleaned - trivial. If the role is inner with the same tags as the relation, it could be considered a hole and the tag discarded.

Edits: This is not always true and it could be an error on the mappers part that would require a careful decision.

Duplicate node

Could be auto cleaned - trivial. Two nodes on the way in the exact same area. JOSM validator flags and fixes automatically.

Duplicate segment ways

Requires manual cleanup - Not trivial. There seems to be many special cases here.

Duplicate segment relations

Could be auto cleaned - trivial. Drop the duplicated member from the relation - screenshot 2016-06-08 17 00 51

Ring not closed

Requires manual cleanup - Not trivial. Possibly invalid, incomplete or junk data. Might need retracing, removal or adding members to incomplete relation.

Way in multiple rings

Not trivial. Might need to be remapped.

Some important features

Most of the features with issues seem to be small landuse areas. I tried to find if there was anything significant on the map that was invalid. Here are a few:

Administrative Boundaries

Notable buildings

Important parks


Open questions

  • It seems like a huge majority of the issues need to be carefully revieved by hand and cleaned up. What does a realistic approach to clean the map look like?
  • The flexibility of the current map editors allows mappers to continue to create features that dont make sense like a way tagged as a forest. Is it time for stricter validity checks on uploads?

Weekly roundup - Suspicous mapping

Posted by manoharuss on 21 June 2016 in English (English)

The amount of data on OSM sometimes boggles the mind, there was 23471 new changesets just yesterday. With so much great mapping work being done by the community, there's always a possibility of a few bad apples. So, here's a collection of a few that I have stumbled across last week (13 - 17 June).

screenshot 2016-06-21 17 36 49

Stumbled on anything suspicous on the map this week? Do drop the mapper a message, for all you know, it was just an honest mistake :) Look forward to another roundup next week.

#ID Editor

Posted by Saikat Maiti on 21 June 2016 in English (English)

It is very interesting to use ID editor for open street map editing. it is also time saving smart tool for open street map. Tagging is very easy and visible for this. I need to explore more, need to learn more shortcut for this. These are very important link to follow (

Location: New Panvel, Panvel, Greater Bombay, Maharashtra, 410206, India

Mapeaton, pedestrian conditions' monitoring

Posted by mapeadora on 21 June 2016 in English (English)

In the development process of #Repubikla, an open community map on the active mobility conditions, we have seen the need to develop a methodology for more specific and visual documentation of the infrastructure where bicycles and pedestrians travel daily. We wanted to develop a permanent and participatory mapping, based on georeferenced photos and itineraries, evaluating sidewalks that hinder foot traffic, obstacles, bad design or poor condition for pedestrian, wheelchairs or pushing a stroller, using a cane or crutches. We call this collective initiative "Mapeaton".

Concretely, what is Mapeaton?

Mapeaton is a user account in Openstreetmap and Mapillary, that can be connected simultaneously by anybody who wants to collaborate in this collective citizen audit. We use applications such as Mapillary or any streetview app, enabling through mobile phone or a tablet to take pictures while you are walking or on a wheelchair, keeping the coordinates. Once connected to a WiFi network, the photos are uploaded to the cloud. Opening Mapeaton account, you can consult, share, download or comment on these photos.

The pics can be used represented on a map (coming in Repubikla-cartoDB), can be downloaded, or can also be shared via social networks, linked to a map location and complete sequence travel photos.

How Mapeaton started working with the community?

Mapeaton started in 2016. We spread in a community way on the occasion of mapping workshops with Repubikla and Openstreetmap editing. It is a tool and methodology observation of public space that we seek to strengthen between the pro active mobility activism. At the moment, have participated Bicivilízate Michoacán, attending the 3rd Congress of the Pedestrian League, communities and students from the Autonomous University of the State of Mexico Campus Toluca and UNAM in Mexico City. The Mapeaton account has already about 5500 images and 40 kilometres mapped in different cities.

Specifically, what do we illustrate?

We can take punctual pictures (manual mode) of problems on sidewalks, nonexistent or misplaced or poorly marked crosswalks, sidewalks with uneven surface, poles, trash, potholes, dangerous inclinations, ramps auto hindering, wheelchair ramps poorly designed, etc. It can also be used to illustrate a line of desire (automatic mode) making a complete track. We can illustrate a well-designed infrastructure that we want to present as a model or a controversial case, as well. We can use Mapeaton individually as we move through the city, or to support a collective walk, as an audit of pedestrian traffic space.

It can also be used as a tool for citizen systematic evaluation of a highly relevant equipment or infrastructure. For this we recommend monitoring with a set frequency, which can be weekly, monthly, bimonthly, covering the infrastructure (if linear) towards one direction and then the other; on one side and then the opposite side; giving a circular turn around this infrastructure covering the maximum possible views, with good lighting and good visibility, without crowd.

We invite everybody to participate, individually or as a collective, in your whole city or in the case of some urban infrastructure you want to assess, document, thus allowing open criticism on public or private investment.

What's Next?

Mapeaton has inspired several actions to systematize scattered actions of citizen audit. Together Openstreetmap Mexican chapter and the Mexican Secretariat of Finances promote the use of open streetviews apps in order to monitor the use of public resources in the development of public works (#transparencia presupuestaria, #tpresupuestaria). EMBARQ Mexico CTS will use Mapillary and the methodology to countries not covered by commercial streetviews, as Tanzania, to perform a road safety audit.

We also promote the creation of open georeferenced images in the case of climate risk assessment in informal settlements; to accurately document temporary flood zones in rainy period in Mexican cities; to understand and illustrate the perspective of women to transit day and night on the town.

Spanish version

Location: Calzada San Antonio Abad, Mexico City, Cuauhtémoc, Mexico City, 06850, Mexico

OpenStreetMap Data Analysis: Entry 1

Posted by Jennings Anderson on 20 June 2016 in English (English)

Howdy OpenStreetMap, I am excited to share that I am working as a Research Fellow with Mapbox this summer! As a research fellow, I am looking to better understand contributions to OSM.

For my first project, I have been using the tile-reduce framework to summarize per-tile visible edits from the Historical OSM-QA-Tiles. These historical tiles are a snapshot of what the map looked like at the time listed on the link.

With this annual resolution, we can visualize the edits (those edits that were visible at the end of that year) that happened on each tile. So far, I've summarized them as a) number of editors, b) number of objects, and c) recency of the latest edit (relative to that year).

The OSM-QA-Tiles are all generated at Zoom level 12, which separates the world into 5Million+ tiles. Some tiles have few objects while others have ten-thousand plus.

So far I have created two interactive maps to investigate OpenStreetMap editing behavior at this tile-level analysis:

1. Editor Density (Number of editors active on a tile)

2. Edit Recency (Time since last edit on the tile)

Editor Density

This map highlights tiles where multiple editors have been active. The most active editors in most cases are automated bots, especially in the more recent years. For best results, moving the slider in the bottom left for Minimum Users Per Tile to 2 or 3 will exclude most of these automated edits.


2007: European Hotspots

By increasing the minimum object and minimum user thresholds, areas of heavy editing activity pop out: 2007 european hotspots

2007: US Tiger Import - Automated Edits

This image of the activity in the US in 2007 has no threshold on the limited number of objects or users per tile, so you can see all of the tiles affected by the 2007 import. If you increase the threshold, it changes dramatically tiger import

Edit Recency

This map shows the recency of edits to a tile, relative to the year of analysis. It looks surprising at first how many tiles are edited at the end of the year, but that is most likely a function of automated bots. Again, if you move the threshold for number of editors or objects per tile, interesting patterns pop out across the world where users may have been active early in the year and then are less active later. The 2010 Haiti Earthquake is a good example, as it occurred in January of 2010.

2007: The stages of the Tiger Import

If we view by latest edit date, relative to the year, we see the state-by-state import in the US:

2008: North Eastern Hemisphere

2008 recency

More to come! -Jennings

Location: Logan Circle/Shaw, Washington, District of Columbia, 20005, United States of America

Rio Olympics Mapathon

Posted by wille on 20 June 2016 in English (English)

Rio 2016 logo

The 2016 Olympic Games are going to start in August 5th in the city of Rio de Janeiro, so it's time to improve the map!

Rio is one of the best mapped cities in Brazil, but we need a lot more detail in some areas. There are a lot of Mapillary photos we can use to gather details, OSM Inspector alerts to fix and some suburbs that needs a better map.

So we scheduled a weekend to improve the map of Rio and everyone can help! We've set up a project in Tasking Manager to avoid editing conflicts. Mapbox will publish fresh imagery and Nighto is going to take some pictures of the Olympic venues with Mapillary. We will be online at the IRC #osm-br channel to chat and coordinate the actions.

See all the details in the wiki page and collaborate with us!

Location: Barra da Tijuca, Rio de Janeiro, Região Metropolitana do Rio de Janeiro, Rio de Janeiro, Southeast Region, Brazil

Getting to know Openstreetmap

Posted by Siddharth Sajit on 20 June 2016 in English (English)

This is the first time using the openstreetmap system and I didn't know how useful and interesting it is at the same time. The fact is that our team used the openstreetmap facility and started the project 'GIS' or Geographical Information System as a part of NATIONAL SERVICE SCHEME (NSS) and did its first mapping of our college 'Vidya Academy of Science and Technology, Thalakottukara'.

It is wonderful how technology can be used to in various ways to fulfill our needs. The task was thought to be difficult at first but, as we proceeded it wasn't difficult as predicted. With teamwork and hard work we developed our college map easily.

The team was divided into sub-groups and given different parts of the college. The collected data and information was edited on to the maps separately and the result, detailed map of college.

With this success we are hoping to map the adopted village of our NSS unit VELUR.

Location: inner road, Velur, Thrissur, Kerala, 680601, India

Film locations

Posted by gonzaldama on 20 June 2016 in English (English)

Grand central terminal

Grand central terminal

Location: Murray Hill, Manhattan, New York, New York City, New York, 10016, United States of America

nodes and stuff

Posted by walley on 20 June 2016 in English (English)

I have created 1 019 658 nodes. I love my nodes!

Location: Pňovice, okres Olomouc, Olomouc Region, Central Moravia, Czech Republic

Street Art: House Art in Nottingham NG4, England

Posted by alexkemp on 19 June 2016 in English (English)

Here are some nice examples of art expressed in the houses themselves. Only one full example, but first let's start with a very beautiful front door in Hillview Road, Porchester, Nottingham NG4 (etched glass + stained glass leaded-lights):

(etched glass + stained glass door in Hillview Road

Next is a modest little shield on the wall of a house in Ernest Road, NG4 (we English have been much influenced by the heraldry of the 14th Century):

heraldic shield in Ernest Road

The district around Ernest Road is full of 1920s & 1930s houses (a period renowned for the quality of it's housing in England as, following the slaughter of the Great War, the nation built “homes fit for heros”). Here is a good example of one of those:

1920s/30s house on Ernest Road

The lead-lights provide internal light for the staircase. I also love the stone lions!

My final, quirky example of house-art comes from the first house built in 1929 on a former apple orchard in (what became) Highfield Drive, Carlton NG4. The date of the house was immortalised by the builders in the leading within the front-door, and the current owners allowed me to photograph it today:—

house built in 1929

Location: Bakersfield, Nottingham, East Midlands, England, NG12, United Kingdom

GSoC 2016 - marking cities

Posted by Mateusz Konieczny on 19 June 2016 in English (English)

It is typical for maps covering large areas to display city labels. It is quite common to mark exact locations by displaying dots, circles or other symbols.

It also seems that labels for cities and towns may be displayed larger to improve the map.

I tested both ideas, without changing algorithm that selects cities and towns to be displayed. Example of before/after tested on UK are available below.

z11 github github

z10 github github

z9 github github

z8 github github

z7 github github

z6 github github

z5 github github

I ma not entirely sure about dots and I will certainly experiment with tweaking them, but I am happy with new sizes for city labels.

Additional before/after are available at

Location: Kosocice, Swoszowice, Krakow, Lesser Poland Voivodeship, Poland

Belgian mapper of the month: Julien Fastré

Posted by escada on 19 June 2016 in English (English)

Can you introduce yourself ?

I have several occupations, and I appreciate that they are in very different domains, althought, it might be tiresome from time to time:

  • I am a software developer at Champs-Libres, where a part of the activities is related to geography. We regularly use data from OpenStreetMap. We also install tile server, Nominatim, etc. Officially this is supposed to be a part-time job, but in reality, it takes much more time.
  • I studied journalism, but after my studies I've always been a community worker. I also work part-time as coach for unemployed women at a feminist association.
  • I have been (and sometime I am still) active in several different associations and movements such as GRACQ, which defends the rights of cyclist, de scouts, some unions, ...

Last, but not least I am a father and I love spending a good part of my life on that !


How and when did you discover OpenStreetMap ?

Purely by accident, in an article of the magazine of GRACQ. It got me inspired to continue. Back then, I started contributing with the things that interested me the most at that time: cycle routes and infrastructure for cyclists.

Do you use OpenStreetMap yourself ?

I need it almost every 2 weeks to localize the office of a customer, or to find my way around a different neighborhood. I am using my smartphone with OsmAnd more and more for this purpose.

I also use the data in my profession: both for our TMS-servers and for our analyzes we copy parts of the database to our servers.

What kind of mapper are you ?

I have the impression that little by little I became a mapper of the second plan. Right now, I do more evangelization around OpenStreetMap than actual mapping. I have organized conferences, met ministers, talked to the administration, etc. This requires some availability and patience. When you do it once, it often occurs that you are asked again. But I would be very happy if others will join me and start bringing the "message" themselves.

The consequence is that I have less time to add new objects to the database and spend more time talking about it. And, I confess, I have the impression that I start losing touch with the basis.

At this moment I am interested in the "social" mapping. I have been a community worker for 10 years and I think that OpenStreetMap is a great tool for this profession: e.g. for the creation of a central database of contacts, and to create maps for the most needy in our community (e.g. homeless people).

There was already a mapping party for the homeless in April, and I think it is a very sympathetic initiative.

What do you map ?

Mmm, I just answered that.. :-)

What is your largest accomplishment ?

I am proud of some of the presenations I gave, especially when some people from the audience came to me with additional questions, and later on became interested in OpenStreetMap or started using it in for their work.

Maybe not an accomplishment per sé, but I met a reasonable number of sympathetic people from the administration in Brussels and Wallonia. They are sincerely enthusiastic about OpenStreetMap, but every administration is like a juggernaut, they have a hard time to change course.

Why do you map ?

To maintain a "common good". I am very motivated by the idea to make and maintain a database with collective knowledge, available to everyone. This gives me the idea that I'm contributing to something that is much larger than myself.

Because our economic system is pushing us in the direction of individualism and glorifies property, I am happy, very happy to see different initiatives (such as OpenStreetMap, Wikipedia, open source, but also the movement of cooperatives and common kitchen gardens) form a counter movement.

I am convinced that on short or mid-long term our current dominant economical system will implode and a mixed system will emerge with a better balance between individual freedom and participation in the community.

Do you do other stuff besides mapping ?

As I already said, I present more than I map, although, occasionally, I find the time to map for Humanitarian OpenStreetMap Team (HOT) projects.

I am also looking forward to moving to a new home, so I have a new neighborhood to start mapping.

Do you have some ideas to grow the OpenStreetMap community ?

I really like the recent initiatives by the Belgian community to welcome new mappers.

The mapathon organised in collaboration with 7 Belgian universities in April of this year and the mapping party for the homeless also attracted new mappers. I am looking forward to similar initiatives.

What is the biggest strength of OpenStreetMap ?

Its community of mappers, its license, ... about everything :-)

I find that OpenStreetMap is always ahead of the large suppliers of databases: when there is a new trend (e.g. infrastructure for cyclists), mappers will immediately start adding those in the most visited areas. The suppliers of the classic databases come afterwards, maybe they are more complete or with more coherence, but they are late, sometimes too late. Sometimes they are never arrive, like in developing countries.

What is the largest challenge for OpenStreetMap ?

The continuous growth of regular contributors in order to keep the map up-to-date.

How do you keep informed about OpenStreetMap news ?

I follow the OpenStreetMap blogs via an RSS-feed. I am also member of the talk-be mailing list, although I do not participate very actively.

Do you have contact with other mappers ?

I see other mappers during mapping parties, but also in certain projects.

Anything else that you want to mention ?

I am very touched by the capability of the community to help and support. It makes me proud to be part of it.


Posted by escada on 18 June 2016 in English (English)

I just started playing with MapContrib made by Guillaume AMAT from France. It's a great tool to create dedicated webpages (or apps if you want) for certain tags.

Here I made one for dog parks

MapContrib Dog Parks

You can also allow other people to edit the map data in the way you want. They can change existing data or add new, in this case dog parks

Editing data

So all nodes that will be added already have have the tag leisure=dog_park.

Another map that I made is for artwork

MapContrib Artwork

You can define the content of the popup for each POI, as well as predefine some possible node types and their tags. Here I defined statues and sculptures:

Node Types

and for statues I defined the 2 base tags tourism=artwork, artwork_type=statue and 2 additional tags that you can fill in to set the artist name and the year the artwork was created

statue tags

The above 2 links to MapContrib can be used on a mobile device, so you can easily add new dog parks and artwork on the go.

People have already defined a number of POI-themes, but you can easily add your own with a simple Overpass Query. I would say, why don't you try it out yourself and get people mapping missing stuff in your town (or across the world)

You can find some additional information (in French) on the wiki

OSMF board meeting report

Posted by imagico on 18 June 2016 in English (English)

Yesterday evening there was a public OSMF board meeting. I was one of the few non-boardmembers attending so i thought i'd give a report of my impressions here.

This was not the first public board meeting, there was one previously last July but this was a singular occurence so it was possibly more of a mock up meeting demonstrating publicly how board meetings go. The one yesterday was held under the premise that this is how board meetings are going to be conducted in the forseeable future which is a very different sitation. A big thanks to the board for taking this step and i hope the OSMF members and the OSM community as a whole acknowledge this by coming to the meetings. With the short announcement and the Friday evening date in Europe the small participation this time was understandable though. This is really public by the way, everyone can listen in, you don't need to present your OSMF membership number or something like that before you are allowed to enter.

I was about ten minutes late so i did not get the start, i came in during some discussion on SotM regarding finances between the board and Rob Nickerson from the SotM working group as invited guest. There were very few non-board members present overall - i think apart from Rob and me there were two others overall.

A few general words on procedure: The meetings are conducted with Mumble which i was already familiar with from the German OSM podcast which was usually recorded with audience via Mumble. You connect your Mumble client to the HOT mumble server (, move into the OSMF board meeting room and can immediately listen to the conversation. Since i was not present at the start i missed any initial statements on procedure. There were no constraints in place this time so i probably could have said something at any time but in general it is likely expected from guests to not speak up freely but only talk when being given the word by the board. You can also mute yourself (which i did) to indicate you are not actively participating.

In general Mumble is not quite like a face to face meeting, you have only acoustic and no visual communication and there is always a small but inevitable time lag in communication. It is more like radio communication. You usually configure your client to only transmit when you press a button to eliminate any background noise when you are not talking. There is also a text message/chat system connected to it which can be used for communication without interrrupting the audio conversation.

On the meeting itself - my general impression was that it was easy to follow, everyone was understandable and none of the current board members has a really problematic accent - Paul a bit of Canadian which you need to get used to, Peda quite strong German tone (which i of course have no problem with) and Ilya a bit of Russian tint (which i find enjoyable). There was occasionally somewhat strong background noise while people were speaking but not everyone can move to a tone studio for the meeting of course.

What happens during a board meeting is the members talk about various topics make decisions on some of them via vote and so on. My general feeling of the whole thing is - i hope this does not sound too harsh - that it is kind of unproductive. I am probably somewhat biased here, being self employed i am not really that used to regular organizational meetings any more - when i am at a meeting these days i tend to get paid by the hour which usually tends to expedite things. But i know from past experience that meetings are often fairly unproductive at least by outward appearence and this board meeting was not an extreme case in that regard at all.

This impression is probably partly because of the setup in Mumble - although you are talking to each other you are not really stitting together. Quite a lot of time is spent essentially on waiting if someone has something more to say on the matter because you cannot indicate this using body language. There is also the occasional conflict when two people try to speak up at the same time and then both back off to let the other have the word. Another factor probably was that because the meeting was public everyone was very guarded and careful with voicing a strong opinion. To get progress on a subject it tends to help if you try to work out topics of disagreement by expressing your standpoint in a very pointed way and possibly even insituating a disagreeing standpoint from someone else. This did not really happen. So this is probably something that will improve in the future when everyone gets more used to the public setting.

I will give two examples of subjects that were discussed:

One topic was the collective database guideline which was approved by the board during the meeting. Procedure for votes is apparenly very formal by the way, Kate (who was chairing the meeting) called every member individually to approve or disapprove. There was some discussion about the examples to be included with the guideline - i did not really understand that, maybe because it was about a third example which was not part of the guideline draft on the wiki. What astonished me about the procedure a bit is that although this was a decision with quite some impact - after all this is now an official statement on the interpretation of the license by the organization holding the rights on the OSM data - there was no recap of the process leading to the guideline, the reasoning behind making the guideline the way it is and how the board thinks this fits into the OSMF mission (which it probably does - but still). Also i would have expected a kind of outlook in lines of where to go from here in terms of developing additional community guidelines or modifying existing ones.

Part of this could have been due to the fact that no one from the license working group was present and the board probably considers the guidelines to be managed mostly independently by the LWG and their role being purely oversight in terms of preventing possible gross blunder in these.

Another topic which was still in a much earlier state of discussion was a possible donation drive for the OSMF to be conducted later this year. Here my understanding was somewhat hampered by the fact that apparently this idea has been already extensively discussed on the face-to-face meeting of which there is not yet a comprehensive record. The discussion was mainly about how to proceed about this regarding the purpose of the donations (what the money is needed for), possible legal implications (if the donations can only be used for the purpose they were announced to be needed for) and timing (what is the best moment to start such a drive). The impression i got from this is that the board considers a fairly general donation drive to support their efforts to put OSMF finances on a less volatile basis (meaning less from hand to mouth and more of a cushion to compensate fluctuation in either income or expenses). One topic touched in that regard was the matter of trust in the OSMF board (specifically by the operations working group which is considered instrumental for a donation drive but also in a broader sense). My own impression is that this in general are important matters and it is good to see these are discussed although i kind of see the risk of starting to build the house from the top. Trust in the board regarding finances is a prerequisite for a successful donation drive and having an overall concept and realistic plans for both income and expenses is necessary to build such trust. With plans for corporate membership and widening general OSMF membership still somewhat vague and little long term (i.e. beyond yearly budgets) plans and directives on expenses (what the money will be spent on and what it will not be spent on) there is little basis to form an informed opinion on an individual matter like a donation drive. I can see the possibility of all of this developing into a solid an trustworthy concept but there is still a lot of work to get it there.

Overall i see the concept of public board meetings on a good way. Mikel made an interesting suggestion to have alternating formal board meetings and more informal talks in between which could make the whole thing more participative and more interesting for the community (although care needs to be taken for this not to degrade into a general chat).

A final suggestion to the board: It would probably be good if in the future you were all easily identifiable on Mumble by your Mumble name for anyone entering at any point in the meeting. IIRC Mikel was kind of cryptic. Maybe just agree on a common form (first name, first + last or OSM username).

Location: Sankt Georgen, St. Georges, Schlatthöfe, Freiburg im Breisgau, Regierungsbezirk Freiburg, Baden-Württemberg, 79111, Germany

Mapathon at BDRCS, June 17th, 2016

Posted by mmahmud on 18 June 2016 in English (English)

After about two months break, the OSM mappers got together for another Mapathon. The venue was the training room of BDRCS (Bangladesh Red Crescent Society). It was like a reunion with the old mappers with many of whom I have not met for quite a few months. I also met some new mappers, one of whom is from my own University.

We mapped the Sirajganj Sadar for a project of ADB (Asian Development Bank). We did the following tasks: ;

After the Mapathon, we had Iftari together. Overall it was a success.

Location: Niketan, Dhaka, Dhaka, Dhaka Division, Bangladesh

We have tracks. Are they any good?

Posted by BushmanK on 18 June 2016 in English (English)

Recent discussion with one of OSM contributors, who edited a forest path, located at narrow straight cutline, crossing pretty dense forest, made me thinking about some good example of how bad tracks can get under the foliage. Since that person used Strava's point cloud, I decided that it would be perfect example.

Let's take a look at this place. It's a clearing for high voltage power line, about 85 meters wide. There is a mixed use pedestrian/bicycle asphalt road (former service road), about 6 meters wide, it goes from south to north. There is another road of similar type and size, which goes to the east. Forest there is mixed (about 40% firs), old grown, about 19 meters tall.

Then, let's take a look at Strava data overlaid on top of high resolution imagery (click on it for original resolution): Click for full resolution

  • Point cloud is quite dense there, and highest density portion width stays about 5.5..6 meters regardless of foliage cover.
  • Width of corridor, fully covered with points (at least one point each 0.5 m) is about 25 meters with clear sky view and about 33 meters under the foliage.
  • Width of full spread corridor is about 45 meters with clear sky and about 85 meters under the foliage.

Spread width does not change immediately, when road goes under the foliage. It's caused by Kalman filter, used in every consumer GPS receiver to reduce random jumps to the sides from user's course line (which improves only appearance, but not quality of data, since it's based on assumption, that receiver moves more along more or less straight/smooth trajectory).

I don't know, how exactly Strava calculates the color of each pixel for their point cloud layer, but if it's just some simple additive method with clipping, highest density area will only grow in time. And it's only a coincidence, that currently its with equals to real width of these roads.

Since all tracks in point cloud are independent, it doesn't make any sense to say, that averaging improves precision (width of corridor). It actually even makes it worse, because more awful tracks piling up there in time. However, accuracy (distance between corridor median line and road median line) grows until certain "saturation point". At least, until full coverage (when each point of layer contains at least one point at highest resolution) within visible corridor will be reached.

What should we learn from it?

Random tracks, even several tens of them, can't be completely reliable under the foliage, especially since foliage density is different, and certain areas may affect GPS reception systematically (cause similar direction of jumps). Foliage potentially increases spread from about 10 meters to each side to 20 meters.

Is this value large? If you don't have any other data there - no, it's okay - there are roads in OSM, traced from Landsat imagery. If you're trying to improve accuracy of paths, traced by any sources, better than Landsat imagery - you probably shouldn't do that, GPS tracks are not enough accurate to give any improvement, even in case of accumulated sets of tracks.

Last Week's Favourite Mapillary Photo

Posted by alexkemp on 17 June 2016 in English (English)

I use Mapillary to upload photos to & to store in the OSM map (a JOSM plugin allows them to be uploaded + shown on the map) (that also allows them to be shown in these diary entries). Mapillary sends me weekly emails, telling me currently that I've uploaded a total of 724 photos & have a total of 741 views. Which is not a lot.

This was last week's most popular photo:—

the most popular photo?!

I think that my photo viewers need to get out more.

Location: Bakersfield, Nottingham, East Midlands, England, NG12, United Kingdom

Group of buildings imported in Boscoreale, Italy

Posted by Chetan_Gowda on 17 June 2016 in English (English)

I noticed buildings imports back in February 2016 which were having building=yes tag for all building nodes. Have captured the details here.

OSM user: geopeppe imported all these buildings and after my message, he cleaned unnecessary tags on nodes but now only exists are:

  • Group of buildings instead of individual buildings.
  • Missing source of the data.
  • The missing documentation of the import.

I'd like to inform the community of Italy about this import and take next actions towards clean up or right documentations.

Location: Rione Provolera, Torre Annunziata, NA, Campania, Italy
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