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Task 3.2: Trial run tool and expert interpretation for known informal settlements #2

Open cgiovando opened 5 years ago

cgiovando commented 5 years ago

An initial TM project was created using a selection of known UNHCR refugee camps: https://tasks.hotosm.org/project/5668

The original subset included 254 point sites across all of Africa. After applying a 3km buffer on each point and dissolving the overlapping areas, a total of 83 distinct tasks were created.

Training on TM and OSM mapping tools was conducted at Oregon State University on Jan 15 by @mataharimhairi. Participants were asked to map settlement boundaries according to instructions in the TM project.

Output from this preliminary mapping task will be used as training data for machine learning processing by @wronk

@mataharimhairi @JamonVDH please add any comments, lessons learned and recommendations from this first project.

mataharimhairi commented 5 years ago

@cgiovando After providing training on the use of TM, iD Editor and JOSM, we devised a workflow for identifying and extracting informal settlement boundaries that we had high confidence in. Jamon the OSU team are writing up our workflow and will share shortly, but in a nutshell the process is as follows:

  1. Select TM task at random
  2. Open in JOSM
  3. Identify if an OSM settlement boundary is present
  4. If present, compare the digitised boundary to DigitalGlobe-Premium imagery to assess whether or not the settlement can be easily identified
  5. Investigate the other tagged features in the area to help confirm that the settlement is a refugee camp
  6. If confidence is high that it is an informal settlement boundary, copy the boundary to a new layer, apply preset and save as a GeoJSON file
  7. Upload file to Google Drive and mark TM task as complete
  8. If there is not high confidence, either leave the TM task as unmapped for someone else to try or if there is very low confidence (i.e. there is no OSM data or nothing present in the imagery), also mark as done and leave a comment

Please note that some of the GeoJSON files saved to the Google Drive are marked as modified, this means that the original boundary was altered slightly to encompass the expanding area of the refugee camps. This is to provide Mark with the most up to date settlement boundaries, without making changes to the data in OSM at this point.