Re: [Talk-ca] Building Import update
Salut John, Voici les résultats d'analyse de géométrie des bâtiments pour Ottawa centre-ville.bbox : 45.4224,-75.6994,45.4568,-75.6122 - 20,372 Bâtiments - 173 Bâtiments avec superposition (0.1%) - 11,534 Bâtiments avec formes irrégulières (56.6%) Nous avons donc un résultat semblable aux imports en Ontario que j'ai analysé il y quelques jours. A mon avis, en haut de 5%, il faut regarder de plus près et expliquer pourquoi autant de formes irrégulières. J'ai créé des Requêtes overpass pour extraire les bâtiments identifiés dans l'analyse. Télécharger les requêtes à partir des fichiers ci-joints. Pierre 173 Batiments avec superposition Req Overpass voirhttps://www.dropbox.com/s/fp1cimouhhfbm9s/on_Ottawa_centre_2019-01-31_batiments_superposes_OSM_req_Overpass.txt?dl=0 11,534 Bâtiments avec formes irrégulières (56.6%) Req Overpass voir https://www.dropbox.com/s/c68nb9dbudtp679/on_Ottawa_centre_2019-01-31_batiments_irreg_OSM_req_Overpass.txt?dl=0 - Le lundi 28 janvier 2019 09 h 17 min 37 s HNE, john whelan a écrit : Interesting, although I'm not sure what the best approach is. 31 Hamilton is interesting. If you look at the buildings next to it they don't have house numbers. Look at the history and you'll see it was first created in 2010 with potlatch and edited once more in 2011. At my first glance at Kingston the small deviations form 90 degrees did not stand out. I think we can reasonably expect Microsoft to create a Canadian buildings file and you seem to be comfortable that the ones it has in the US are of a reasonable standard. Part of my background is large databases and my personal view is the minimum data needed the faster the system runs and less data needs to get flipped round and backed up. Could you run the analysis over Ottawa? Looking closely at a few in Ottawa I note that there are some bay windows and other small features I might not have bothered with if mapping with JOSM with the buildings_tool. Because of a few 45 degree angles involved this isn't something that can be easily solved. Ottawa I think at some level can be considered a reasonable success. Certainly we added a lot of extra information to the building outlines. I think the trade off is using the municipal data gives us the buildings with perhaps more detail than I might like but many would like to see the buildings imported. Dunno (Do not know for translate tools.) What is the ideal building outline in OpenStreetMap? What is an acceptable building outline in OpenStreetMap? Suggestions Thanks Cheerio John ___ Talk-ca mailing list Talk-ca@openstreetmap.org https://lists.openstreetmap.org/listinfo/talk-ca
Re: [Talk-ca] Building Import update
I can't think of a way to pull in all the suspect buildings but if you have a look here: https://www.openstreetmap.org/search?query=k4a%201m7%20canada#map=19/45.47095/-75.48696 556, 558, 560 are all examples that I think would fail your test. However they are the shape of the buildings. As far as I am aware we haven't had any outraged users complaining about the building shapes in Ottawa and that I think is the acid test. The Ottawa building import has been useful certainly in gaining new mappers and adding tags to the outlines. Your test originally was to pick out very badly mapped buildings that had been done in iD and I would agree with you that some were very bad. Sometimes 3 or 4 times the size of the building and some very odd shapes indeed. From memory most were done on HOT tasks with the iD editor. These I think we should definitely aim to avoid but where the representation of the building is reasonably accurate then I think they are acceptable. We are using reasonably experienced mappers who would balk at importing some of the stuff we saw in Nepal etc and rightly so. They'd almost certainly be very vocal about the quality of the data. There is a case to be made that most residential buildings would be acceptable if they were mapped with the JOSM buildings_tool plugin and all the small blobs take up database size. There is also a case that you get a better sense of the building with the small blobs, bay windows etc. I don't have strong feelings either way but I strongly suspect there are examples of both already in OSM in Canada. I note that both Google and Bing have most buildings these days and it has almost become a map user expectation. Certainly there are apps that guide blind people that use the building outlines in OSM. There is a case that says to keep up with the competitors we really ought to have buildings. I think someone else has commented that parts of the Microsoft building outline from scanned images in the US is problematic. So given the results in Ottawa are comparable to Ontario and in my opinion Ottawa is acceptable then I think the rest is also acceptable. Certainly Kingston where not all building angles were right angles weren't noticeable to me by eye or perhaps my eyesight is just getting worse with age. Cheerio John On Thu, 31 Jan 2019 at 19:51, Pierre Béland wrote: > Salut John, > > Voici les résultats d'analyse de géométrie des bâtiments pour Ottawa > centre-ville. > bbox : 45.4224,-75.6994,45.4568,-75.6122 > > - 20,372 Bâtiments > - 173 Bâtiments avec superposition (0.1%) > - 11,534 Bâtiments avec formes irrégulières (56.6%) > > Nous avons donc un résultat semblable aux imports en Ontario que j'ai > analysé il y quelques jours. A mon avis, en haut de 5%, il faut regarder de > plus près et expliquer pourquoi autant de formes irrégulières. > > J'ai créé des Requêtes overpass pour extraire les bâtiments identifiés > dans l'analyse. Télécharger les requêtes à partir des fichiers ci-joints. > > > Pierre > > > 173 Batiments avec superposition > Req Overpass voir > > https://www.dropbox.com/s/fp1cimouhhfbm9s/on_Ottawa_centre_2019-01-31_batiments_superposes_OSM_req_Overpass.txt?dl=0 > > > 11,534 Bâtiments avec formes irrégulières (56.6%) > Req Overpass voir > > https://www.dropbox.com/s/c68nb9dbudtp679/on_Ottawa_centre_2019-01-31_batiments_irreg_OSM_req_Overpass.txt?dl=0 > > > > > > > > - > > Le lundi 28 janvier 2019 09 h 17 min 37 s HNE, john whelan < > jwhelan0...@gmail.com> a écrit : > > > Interesting, although I'm not sure what the best approach is. > > 31 Hamilton is interesting. If you look at the buildings next to it they > don't have house numbers. Look at the history and you'll see it was first > created in 2010 with potlatch and edited once more in 2011. > > At my first glance at Kingston the small deviations form 90 degrees did > not stand out. > > I think we can reasonably expect Microsoft to create a Canadian buildings > file and you seem to be comfortable that the ones it has in the US are of a > reasonable standard. > > Part of my background is large databases and my personal view is the > minimum data needed the faster the system runs and less data needs to get > flipped round and backed up. > > Could you run the analysis over Ottawa? > > Looking closely at a few in Ottawa I note that there are some bay windows > and other small features I might not have bothered with if mapping with > JOSM with the buildings_tool. Because of a few 45 degree angles involved > this isn't something that can be easily solved. > > Ottawa I think at some level can be considered a reasonable success. > Certainly we added a lot of extra information to the building outlines. > > I think the trade off is using the municipal data gives us the buildings > with perhaps more detail than I might like but many would like to see the > buildings imported. > > Dunno (Do not kn
Re: [Talk-ca] Building Import update
On Jan 31, 2019, at 5:47 PM, john whelan wrote: > > I note that both Google and Bing have most buildings these days That's a strong assertion, any cite you might make? Or are you simply guessing? Also, so what? And, "most?" > and it has almost become a map user expectation. Do you have any sources to cite for this? Bing users? Google Maps users? OSM users? Who, exactly is "expecting" this and how do you know this? What matters here and now is the OSM community's acceptance of the quality of these data. Is Canada able to MAKE such a determination? I think so. > There is a case that says to keep up with the competitors we really ought to > have buildings. John, I believe you are the first to ever assert "we ought to have buildings" I've ever seen in OSM. What "case" are you talking about? > I think someone else has commented that parts of the Microsoft building > outline from scanned images in the US is problematic. Well, then say so. Say who. Say when. Say where. Say what you mean by "problematic." Let us (the OSM community) reflect on these comments. Let us (the OSM community) make our own determinations whether this is or isn't "problematic." Those issues are a completely separate issue from OSM, although there might be overlap, I simply don't know, as you haven't given us any data, simply your opinion. I'd like to know, but I can't, given what you have offered. > So given the results in Ottawa are comparable to Ontario and in my opinion > Ottawa is acceptable then I think the rest is also acceptable. OK: one vote in the fog of consensus. I have very little data to go on, and I'm not completely certain why, but it is an assertion of an OSM volunteer saying "then I think..." something. > Certainly Kingston where not all building angles were right angles weren't > noticeable to me by eye or perhaps my eyesight is just getting worse with age. Canada (and OSM) either agrees its building data for the five provincial datasets are OK, or Canada (and OSM) don't. As I've heard many here (I don't need to cite them, these cite themselves) say "I don't" or "we don't" (think the datasets are OK), the next things to say are "Well, they seem fixable with some algorithmic/programatic massaging, so, how do we fix them?" Or, "OK, here's how we're going to fix them." (Simplify the nodes, make them have 90º angles, whatever). This doesn't seem like it's an impossible finish line to cross, though I do see at least one person running in detours going nowhere. In short: "what's wrong with these data, how might they get fixed?" (Then they might get imported). It doesn't seem to me to be a whole lot more complicated a discussion than that. SteveA ___ Talk-ca mailing list Talk-ca@openstreetmap.org https://lists.openstreetmap.org/listinfo/talk-ca