OpenStreetMap

Chetan_Gowda's Diary

Recent diary entries

Printable Kannada Maps

Posted by Chetan_Gowda on 2 October 2021 in English. Last updated on 3 October 2021.

Since last weekend, I was trying to make Kannada maps. To give a shot, I chose Chamarajanagar district, Karnataka. The data is from OpenStreetMap and SRTM.

Here are some of the output in different styles:

chamarajanagar

map

Please give feedback to improve in case.

Happy mapping!

Location: Advalli, Kuvempunagara, Hassan, Hasana taluk, Hassan District, Karnataka, 573201, India

Plot simple map using R

Posted by Chetan_Gowda on 19 January 2021 in English. Last updated on 21 January 2021.

You can plot simple Stamen map (© OpenStreetMap contributors) in R using below steps:

Install below packages in R Studio:

install.packages("sf")
install.packages("ggplot2")
install.packages("ggmap")

Once you installed, do load them using below code:
library(sf)
library(ggmap)

Next go to Geofabrik Tile calculator and copy the desired location co-ordinates.

Example: I copied Bengaluru co-ordinates using Coordinate Display tab under Osmosis copy and stored in bengaluruCoords like below:

bengaluruCoords <- c(left=77.17, bottom=12.59, right=78.05, top=13.34)

Finally run below code to generate map tiles:
get_stamenmap(bengaluruCoords, maptype = "terrain") %>% ggmap()

Here is the output: Screen Shot 2021-01-18 at 11 07 50 PM

Happy mapping & coding!

Location: 13.038, 77.556

State of the Map Asia 2018

Posted by Chetan_Gowda on 27 October 2018 in English. Last updated on 27 April 2021.

sotm-pink

OpenStreetMap India community is excited to announce and host State of the Map Asia 2018 in Bengaluru on November 17-18. This is the 4th annual Asia OSM conference and we are thrilled to welcome OpenSteetMap community and share their amazing journey. Do check for interesting keynotes, talks and workshops in program schedule.

How do I register?

This event is open to everyone, even if you are not speaking at the session :)

If you have questions regarding registrations, venue or any other related queries, please email to stateofthemapasia+enquiries@gmail.com or reach out to @SotmAsia.

Looking forward to see you all!

OpenStreetMap Evolution

Posted by Chetan_Gowda on 6 August 2018 in English. Last updated on 10 August 2018.

OpenStreetMap evolved since many years. Millions of contributors are helping this project to grow everyday. Inspired by some of my friends, Karnataka and Ireland evolution projects, I wanted to vizualize different parts of the world.

Sharing simple animated GIF that I created using Mapolution on Docker on my Mac showing different countries’ OSM edits over years. The snapshots are taken for every 30 days from the starting date.

srilanka-2015-01-01-2018-07-31 Sri Lanka (January 2015 - July 2018)

thailand-2008-01-01-2018-07-31 Thailand (January 2008 - July 2018)

bangladesh-2015-01-01-2018-04-30 Bangladesh (January 2015 - April 2018)

taiwan-2008-01-01-2018-07-31 Taiwan (January 2008 - July 2018)

drc-2016-01-01-2018-07-31 Democratic Republic of the Congo (January 2016 - July 2018)

peru-2010-01-01-2018-04-30 Peru (January 2010 - April 2018)

ethiopia-2017-01-01-2018-07-31 Ethiopia (January 2017 - July 2018)

bhutan-2008-01-01-2018-04-30 Bhutan (January 2008 - April 2018)

I was able to create all the above animations based on their data size which were compatible with my computer memory. Most of these countries have datadump lesser than 200MB. If you want to create GIF’s of your own, you can follow below steps:

Docker setup for Mac

  • Signup for Docker hub, download it freely and install it.
  • Test whether docker running correctly in terminal. To test quickly, run docker --version and docker run hello-world.
  • Create an Ubuntu 16.04 container with docker run -it ubuntu:xenial bash

Libosmium and dependencies installation

  • Create a working directory (E.g: work) mkdir work and update Ubuntu by running apt update
  • Install git apt install git and clone libosmium git clone https://github.com/osmcode/libosmium.git
  • Install libosmium dependencies. You can install all dependencies in one go apt install -q -y cmake doxygen g++ graphviz libboost-dev libbz2-dev libexpat1-dev libgdal-dev libgeos++-dev libproj-dev libsparsehash-dev make ruby ruby-json spatialite-bin zlib1g-dev
  • Install protozero by running apt install libprotozero-dev
  • Compile and build by following 5 steps: cd libosmium mkdir build cd build cmake .. make
  • If you want gdalcpp and utfcpp libraries to be installed along with libosmium itself when calling make install, you have to use the CMake options INSTALL_GDALCPP and/or INSTALL_UTFCPP with cmake -INSTALL_GDALCPP -INSTALL_UTFCPP ..
  • At last call ctest to run tests. If you dont get any errors, Congrats! your libosmium setup is complete!

Build Mapolution

  • Clone osmium-contrib git clone https://github.com/osmcode/osmium-contrib.git to working directory.
  • Change directory cd osmium-contrib
  • Install boost_filesystem and boost_program_options packages apt install ibboost-filesystem-dev libboost-program-options-dev
  • Now build by these 4 steps: mkdir build cd build cmake .. make
  • After building osmium-contrib, change directory to mapolution cd osmium-contrib/mapolution
  • Install remaining dependencies one by one apt install bc imagemagick and GDAL library gdal_rasterize package by running apt install libgdal-dev gdal-bin
  • Install gifsicle apt install gifsicle
  • Now build mapolution: mkdir build cd build cmake .. make
  • You can switch to different handler:cmake -DHANDLER=RoadsHandler .. This will filter only highways from the country extract. To get buildings, switch to BuildingsHandler

Download data

  • Download any small country data from Geofabrik.
  • Copy country data to container from host from a new terminal window tar -cv <country.osh.pbf> | docker exec -i <container_name> tar x -C /home/work/osmium-contrib/mapolution/build For example: tar -cv bhutan-internal.osh.pbf | docker exec -i practical_banach tar x -C /home/work/osmium-contrib/mapolution/build

Run Mapolution

  • After copying to build directory, run following command ./mapolution -s 2010-01-01 -e 2018-07-31 -S 30 country.osh.pbf (-s start date, -e end date, -S number of days) - This will create an out directory where shapefiles were stored.
  • Run ./rasterize.sh to get final GIF output as anim.gif
  • Now, from another terminal window copy anim.gif to host from container sudo docker cp <container_id>:/home/work/osmium-contrib/mapolution/build/anim.gif . For example: sudo docker cp fbb0afd5e095:/home/work/osmium-contrib/mapolution/build/anim.gif .

That’s all! You’ve got animated OpenStreetMap evolution. Let me know if you could able to create one by these steps and post your result in comment. Happy mapping :)

Thanks to Jochen Topf and yogi_ks for helping out in resolving issues and docker setup on Mac.

125 million MS Building Footprints

Posted by Chetan_Gowda on 31 July 2018 in English. Last updated on 1 August 2018.

Recently, Microsoft released 125 million US building footprints as open data across 50 states. The data is freely available for download and use. You can read about previous release of 9.8 million buildings here.

With the help of tippecanoe and Mapbox Studio, I have visualized Hawaii dataset to know how data looks like.

Sharing few screenshots and gif: Honolulu

The dataset doesn’t contain height attributes and looks good for me. You can find it in Github.

Mapbox recently rolled out new satellite imagery for many places around the globe. I’m happy to share that some of the Indian cities also got new imagery with this update and the community can use this for mapping in OpenStreetMap. I always prefer best imagery to add highways and buildings the most.

bengaluru Bengaluru, Karnataka

ludhiana Ludhiana, Punjab

kochi Kochi, Kerala

chennai Chennai, Tamil Nadu

kolkatta Kolkata, West Bengal

vellore Vellore, Tamil Nadu

You can also check the unmapped places on OpenStreetMap using this tool http://lxbarth.com/compare/?osm&mapbox.satellite#17/30.91342/75.84278. The tool compares the satellite imagery alongside OpenStreetMap. Here is the one example in Gottigere neighbourhood in Bengaluru, where buildings can be mapped.

gottigere_blr Gottigere neighbourhood, Bengaluru

screen shot 2017-10-13 at 3 46 58 pm Ludhiana, Punjab

Let me know if you have any questions and feedback. Here is the link http://learnosm.org/en/ to the web tutorial to get started with editing in OpenStreetMap. Also there is lot more tutorials are available at here.

Happy mapping!

HOT Mapathon

Posted by Chetan_Gowda on 27 July 2017 in English.

Hello all, Namasthe! 🙏 We had an amazing HOT Mapathon on July 21st at Mapbox India office. We had the local OSM community along with folks who were mapping for the first time adding approximately 3000 buildings in Cambodia for Eliminate Malaria task.

The good thing about this event was that most of them knew about OpenStreetMap and very few people were new into mapping activity. At first, we introduced to OpenStreetMap, it’s data model, and good practices one should know while editing and a short demo of editing in iD editor.

Few Photos

Upendra introducing the HOT and it’s objectives

Jinal Foflia helping the participant for mapping

Many of us discussed about ongoing mapping activities in Africa with more emphasis on FGM and Malaria issues and how non profit organisations are utilising the data that people produce to save many lives. Also, we’ve discussed about upcoming State of the Maps in Japan, US and Nepal. Some of the questions they asked are like, how data produced by many people been validated? who will take care of ground truth? and what is the community capacity right now? and so on. Hope we cleared all of them!

We hope to have many more events in the future with the community and help for humanitarian purposes.

Best, Chetan

thumb-2048 1

‍‍ಕನ್ನಡ ನಾಡು ಕಂಡ ಮೇರು ನಟ, ನಟಸಾರ್ವಭೌಮ ಡಾ. ರಾಜ್ ಕುಮಾರ್ https://en.wikipedia.org/wiki/Rajkumar_(actor)‍ ಅವರ ಸ್ಮಾರಕವನ್ನು ಈಗ ಎಲ್ಲರೂ ‍‍ಮ್ಯಾಪಿಲರಿಯ ಮೂಲಕ ಕುಂತಲ್ಲೆ ವಿಕ್ಷಿಸಬಹುದು. ‍ಕನ್ನಡ ನಾಡು ನುಡಿ ಮತ್ತು ಚಿತ್ರರಂಗಕ್ಕೆ ಅವರ ಕೊಡುಗೆ ಅಪಾರ. ಚಿತ್ರರಂಗದಲ್ಲಿನ ಜೀವಮಾನದ ಸಾಧನೆಗಾಗಿ ಭಾರತ ಸರ್ಕಾರವು ಚಿತ್ರರಂಗದ ಅತಿ ದೊಡ್ಡ ದಾದಾಸಾಹೇಬ್ ಫಾಲ್ಕೆ ಪ್ರಶಸ್ತಿ ‍ಯನ್ನು ನೀಡಿತು. ಇತ್ತೀಚೆಗೆ ಗೂಗಲ್ ಇಂಡಿಯಾ ಅವರನ್ನು ‍ಗೂಗಲ್ ಡೂಡಲ್‍ ‍ಮೂಲಕ ಗೌರವಿಸಿತು. ‍

rajkumars-88th-birthday ‍ ಮ್ಯಾಪಿಲರಿಯ ಸಹಾಯದಿಂದ ನಾವು ಓಪನ್ ಸ್ಟ್ರೀಟ್ ‍ಮ್ಯಾಪ್ ಉತ್ತಮಗೊಳಿಸಲುಬಹುದು. ಉದಾಹರಣೆಗೆ: ಸ್ಮಾರಕದಲ್ಲಿನ ಎಲ್ಲ ರೀತಿಯ ವೈಶಿಷ್ಟ್ಯಗಳ‍ನ್ನು ಮ್ಯಾಪ್ ಮಾಡಬಹುದು. ‍ಇಲ್ಲಿ ಅವರ ಬಗ್ಗೆ ಬರೆಯುವ ಕಾರಣವಿಷ್ಟೇ, ಭಾಷಾಬಿಮಾನ ಹಾಗೂ ಕನ್ನಡತನ. ಭಾರತದಲ್ಲಿ ಎಲ್ಲಾ ಭಾಷೆಗಳು ಸಮಾನವಾಗಿದ್ದು, ಆ ಬಾಷೆಗೆ ಅದರದ್ದೆ ಆದ ವೈಶಿಷ್ಟ್ಯಗಳು ಹಾಗೂ ಇತಿಹಾಸವುಂಟು. ಮೇಲಾಗಿ ಈಗ ಓಪನ್ ಸ್ಟ್ರೀಟ್ ‍ಮ್ಯಾಪ್ ನಲ್ಲಿ ಕನ್ನಡ ‍ಮೊದಲನೆ ಸ್ಠಾನದಲ್ಲಿ ಇರುವುದು ಖುಷಿಯ ವಿಚಾರ. ಅದಕ್ಕೆ ಎಲ್ಲರ ಶ್ರಮವುಂಟು. ‍

thumb-2048 2ಹೊಸಬೆಳಕು, ಭಕ್ತ ಪ್ರಹ್ಲಾದ ಮತ್ತು ಕಾಮನ ಬಿಲ್ಲು ಚಿತ್ರಗಳಲ್ಲಿ

thumb-2048 ‍ಅವರ ೨೦೮ ಸಿನಿಮಾಗಳಲ್ಲಿ ನನಗೆ ಮೂರು ಚಿತ್ರಗಳು ಪ್ರಭಾವ ಬೀರಿದವು ಎಂದರೆ - ಮಯೂರ, ಬಂಗಾರದ ಮನುಷ್ಯ ಹಾಗೂ ಕಸ್ತೂರಿ ನಿವಾಸ.

ಬನ್ನಿ ಹೆಚ್ಚು ಹೆಚ್ಚು ಕನ್ನಡಪರ ಕೆಲಸ ಮಾಡೋಣ. ಅದಕ್ಕೆ ಸ್ಪೂರ್ತಿ ಯಾರೇ ಆಗಿರಲಿ. ವಂದನೆಗಳು!

Microsoft 9 million 3D buildings

Posted by Chetan_Gowda on 14 June 2017 in English. Last updated on 7 April 2021.

Microsoft recently released 9.8 million building footprint data of 102 cities covering 44 US states to the OpenStreetMap community. This is a huge boost to improve the building data in many parts of the United States. Right now, we have ~ 19 million buildings already added by the community through imagery tracing and imports.

The most exciting part of this data is that all the footprints have height information. That means we can generate simple 3D buildings. I downloaded all the data and created a Mapbox style with 3D extrusion:

In general, the data is of good quality and will improve the building coverage in the US by 150%. But the quality may vary from city to city. Local mappers should evaluate each city before deciding to import.

Feel free to play with data, post your findings or screenshots of the data evaluation for the city you are interested in and let the community know how valuable this data is going to be for OpenStreetMap.

Code and step is available in Github repo: https://github.com/osmlab/ms-building-import/

* California not included in the tileset since OSM has fairly good coverage

Last weekend, I tried modelling San Francisco City Hall in S3DB. The public building has 100 years of glorious history. The diameter of the central dome is around 34 m and total height of the building is 93 m. From Wikipedia

The co-ordinates of the building is 37.77910°N/122.41937°W. Edited this model first through OSM Sandbox and copied all the geometries and tags to main OSM database. I used JOSM current version and Kendzi3D plugin to visualise locally.

Before Simple 3D tags

before_in_kendzi Visualised in JOSM Kendzi3D plugin

After adding Simple 3D tags

Photo credits: At Flickr by Thomas Hawk

globe

after_in_kendzi

Rendering

1. F4Map f4map Click here for demo

2. OSMBuildings osmbuildings Click here for demo

I’d love to see many places in OpenStreetMap in 3D. If you have any questions, ping me @chtnha on twitter or OSM message.

In 2016, San Francisco city Government published LiDAR-derived building footprints that include both geometry and height information. One of the main goals of the San Francisco OpenStreetMap community was to import this height data to the existing buildings in OpenStreetMap. The project was initiated by SF community in November 2016, recently Brandon and Daniel lead a great Mapathon at Mapbox SF office.

sf_illustration

Together with the community, Mapbox data team remotely joined and imported nearly 140,000 building heights to OpenStreetMap. Now we can get a real world like experience using popular 3D renderers like OSM Buildings and Mapbox GL JS or create realistic city using Blender or style buildings using Unity. Cheers to the all of them who made this project successful!

screen shot 2017-04-06 at 10 47 27 am

We will be validating these buildings through street level imageries. Both Mapillary and OpenStreetCam have great coverage in San Francisco City.

Tasking manager:

http://tasks.openstreetmap.us/project/71

OSM/Mapillary comparison tool:

Right now we are using comparison tool to validate these buildings heights. Here are the detailed instructions to validate these buildings.

Please get in touch with the community in the Gitter channel for validation and for other updates.

Maptime SF/MaptimeOAK and Mapbox SF are hosting a Mapathon on March 14th, Tuesday at 6:30 pm PST to import building heights. Please RSVP to SF OpenStreetMap Community to be a part of this awesome project.

1200px-sanfrancisco_from_twinpeaks_dusk_mc Image from Wikipedia

San Francisco has building footprints, Points of Interest, and traffic signals for the entire city in OpenStreetMap. All these map features makes San Francisco as one of the well mapped cities on OpenStreetMap. In 2016, the San Francisco city Government published LiDAR-derived building footprints that include both geometry and height information. One of the goals of the SF OpenStreetMap community is to add height information to existing buildings in OpenStreetMap.

To jump in quickly into the project, do check the OpenStreetMap wiki to know more and talk to the community on Gitter to get involved. Also, make sure to create a dedicated OSM import account before jumping into the task and post it here.

Validate these beauty care shops

Posted by Chetan_Gowda on 21 December 2016 in English. Last updated on 7 April 2021.

This changeset look suspicious where a user added lot of point’s of interest like amenity=coffee, and amenity=beauty shops in Mexico city, Mexico. The user used Maps.me editor to add data.

screen shot 2016-12-21 at 4 42 56 pm

My colleague @upendrakarukonda has left a comment on the changeset 3 months ago and removed only coffee shops. Again, I’ve commented for the second time on another changeset. We didn’t observe any reply from the mapper since. So sharing here with the community to examine beauty care places and take necessary actions.

Thank you

Adding height to City of San Francisco buildings

Posted by Chetan_Gowda on 25 November 2016 in English. Last updated on 6 March 2017.

The SF Bay area community is trying to import height data for buildings in the city of San Francisco.

sf_comparison

Why we are adding height tag?

Adding height to existing buildings will enhance the data especially when used with popular renderers like OSM Buildings and Mapbox GL JS.

What is the source of data?

We are using raw LIDAR derived building height data released by SF local government under a CC0 (Creative Commons) license (data download here).

How are we combining the height to existing buildings?

For each building in OSM, we compare the footprint from SF goverment buildings, if there is 70% overlap, we add the height. Buildings with existing height tag won’t be touched.

The task is hosted in OSM-US. The importing has begun at http://tasks.openstreetmap.us/project/71

Note: Before jumping into the task, please read all the instructions carefully.

To know more about the project, or if you have ideas please post them here:

Weekly roundup of edits

Posted by Chetan_Gowda on 7 August 2016 in English.

Here are the few OSM edits we have noticed in the last week. Observed that many experienced mappers need to think of a good changeset comments while they upload their changes to main database.

If you come across any unexplained mapping from an OSM user, let them know through your changeset comments and send them related resources, wikis, tagging system to new mappers, and encourage them to map in good way.

Thank you!!

Weekly roundup of edits

Posted by Chetan_Gowda on 31 July 2016 in English.

Observations of mapping behaviour on OSM can give an insight into recognizing recurrent mapping problems our mappers are facing. Here are few of the issues observed between 18th July - 28 nd July on OSM:

  • House numbers were given in name=* tag: 1. Community responded with a comment and provided building wiki resource to the user.

  • ‘casa’ spanish for ‘Home’ were given to residential buildings:1. Community responded with a comment.

  • Buildings were given name=* tag with key values such as ‘Cra’, ‘Calle’, ‘Betos’, and house numbers: [1] (http://www.openstreetmap.org/changeset/38657218#map=17/11.00815/-74.79661). Community responded with a comment.

  • Classification of highways were changed in Moscow: 1. The Russian community responded with a comment.

  • Lots of untagged nodes, market place was deleted: 1, 2. Community member reverted 1st changeset and commented on the 2nd one.

  • Retraced highway over previously existing one creating crossings: 1. Community responded with a comment.

  • Deleted highway: 1. Community responded with a comment.

  • Castles added: 1. Community member responded with a comment.

  • Lot of highway=road tags: 1, 2.

  • Failed import: 1

  • A ton of tourism = attraction, tourism = camp_site tags added:

If you come across any unexplained mapping from an OSM user, let them know through changeset comments. It starts a constructive discussion we can learn from and creates a positive environment for the OSM community to work together.

Look forward to seeing more of this next week.

Group of buildings imported in Boscoreale, Italy

Posted by Chetan_Gowda on 17 June 2016 in English. Last updated on 20 June 2016.

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: Massa, Boscoreale, Napoli, Campania, 80042, Italy

Data quality is as important a function for any contributor to know as is adding large quantities of detailed data to OpenStreetMap. If we were talking one or two individuals editing, quality assurance would be straightforward, but what about with 2.4+ million registered users adding 2,000,000+ nodes a day?

Luckily, the tireless vigilence of active contributors is a source of some consolation but nearly not sufficient by itself. The important question then becomes, how can we detect and remedy mistakes and acts of vandalism as and when they happen? In trying to find answers we’ve put together a “Validating OpenStreetMap Guide” which aims share our learnings to working with OpenStretMap. The guide covers the basics of handling data validation in OpenStreetMap by defining problematic data, tools for detection, methods for investigation, and avenues for resolution for individual and community mapping efforts.

History panel showing different details about users and versions

By sharing this we’d love to get your feedback on if we’re on the right track, and suggestions on how this guide can be improved to help bring an unparalleled level of data completeness that OSM users worldwide can benefit from.

The union territory of India, Chandigarh has been mapped well with neat buildings, highways. There are so many OSM contributors to this city. OSM India community is thankful to all the mappers who have contributed to mapping the city in a detailed manner. Oberaffe and chandusekharreddy have made mentionable number of edits . : )

screen shot 2016-02-15 at 3 27 10 pm

screen shot 2016-02-15 at 3 31 19 pm