I'm referring to the building footprints as seen on the World Topographic Map. They obviously are referring to some kind of vector data repository somewhere. I would like to be able to extract them to a separate, editable, feature layer (areal).
Generally, to answer your question, it can be divided into two aspects:
1. Yes, you can extract; however, that would be a 'manually digitizing' approach, if you can locate your buildings from any ESRI or Bing basemaps. The reason is: those basemaps are not feature class or raster imagery. Inversely, most are 'cached & fused' tiles..
2. Technically and operationally, there are some techniques to automatically extract features from raster imagery (airphotos, satellite imagery), including building footprints. The effective one is called 'object-oriented' feature extraction. Pls refer to Creating building shape-files from aerial photos
See answer above, it's the Topographic Map I'm trying to extract from so it's not technically "imagery" per se. I assume the data origin is vector so there must be a way to find it.
Yes, the World Topographic Map is created from vector data in a database. However only the cached tiles, images of the map, are presented to the end user. The vector data has not been made accessible to the public.
However, a lot of the data comes from national providers (you can see the list in the bottom right corned of the ArcGIS.com map. You can work backwards from there and see if the data is accessible to the public. Even some of the cities may have open data sites you can check for data.
Hope this helps!
Personally, most ESRI basemaps, including Topographic Map, are ‘fused & cached’ tiles, which are hosted at the server, even though those 'tiled' sources are from feature classes or others in SDE. To the public, only way to extract is to digitize, if features can be located from the basemaps.
However, I see your points from your questions. In fact, Google Maps offer individual layer of ‘cached’ tiles like buildings, roads, rivers, etc.
Some of the servers like ArcGIS Server and Google Earth Enterprise (GEE Server, GEE Fusion) offer this type of capability. For example, if databases built and configured to fit this type of pouposes, you will have a way to extract / export specific 'cached' layer under certain AOI, including GEE Fusion and Google Earth EC/ Pro (GE EC/ Pro) …