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Would someone be able to help me out by explaining to me what the standard technique is to create building outlines on a map such as what google maps has in their 2d map view when zoomed in? I am assuming places such as google used aerial imagery & other methods to create these building outlines? I saw some people that used lidar data where available in certain places but I was trying to figure out if there was some method that could be used to create these building outlines using already existing public data such as satellite images and other means. Thanks

asked 19 Jul '17, 23:47

comp_user's gravatar image

accept rate: 0%

I trace them, usually using the Bing imagery layer in JOSM. There is a building tool plug-in for JOSM that is supposed to make it easier/quicker but I find that it is faster for me to simply click around the perimeter with the drawing tool then use the "q" key to square it up (assuming a building that can be squared up).

There have been some imports of building outlines from governmental or other sources that have appropriate licensing (that is how many/most of the buildings in Los Angeles county were recently entered into OSM). But a lot of it is plain grunt work. I typically do my tracing after I've walked an area collecting street numbers and am entering the house number data.

Now that there are starting to be tools to help enter and render 3D buildings I guess I should start learning that tagging. Always more improvements that can be made even in areas you live in and have, you thought, throughly mapped.

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answered 20 Jul '17, 02:04

n76's gravatar image

accept rate: 17%


@stf the easiest 3D tags to add are building:levels and roof:levels, just count the number of levels.

(20 Jul '17, 05:39) escada

While there are tools to trace building automatically/algorithmicaly from satellite (and maybe lidar) imagery, they are currently more trouble than they're worth unless the imagery is unusually clear (and typically only works for flat-roofed buildings). Tracing water bodies using those tools is a bit more likely to work but still not great.

(20 Jul '17, 09:24) Vincent de P... ♦

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question asked: 19 Jul '17, 23:47

question was seen: 3,244 times

last updated: 20 Jul '17, 09:24

NOTICE: is no longer in use from 1st March 2024. Please use the OpenStreetMap Community Forum