Re: [Talk-ca] James work on Task Manager

[Daniel @jfd553]

First, do you want to be the local import manager?
We agreed to use the Squamish region as a benchmark to test the proposed import 
procedure [1]. Are you aware of this procedure?
We also agreed that this import required some know-how with JOSM. Do you feel 
comfortable enough with JOSM to be involved? What about the other members of 
your bike club?

Any comments?
Daniel

[1] https://wiki.openstreetmap.org/wiki/Canada_-_The_Open_Database_of_Buildings

From: jonab...@gmail.com [mailto:jonab...@gmail.com]
Sent: Monday, February 24, 2020 08:24
To: talk-ca@openstreetmap.org
Subject: Re: [Talk-ca] James work on Task Manager

When James has finished tweaking the Task Manager, I would like to test it out 
with our local bike club along with Mapillary streetview. 
http://tasks.openstreetmap.in/project/84

Jonathan


Hi all,
I was able to split Squamish into Quadtree tiles with a maximum of 200 
buildings each. James is now looking into whether/how this could be implemented 
in the task manager. If no one else is volunteering to be the local import 
manager this week, I will do the work and contact Squamish's local mappers. 
Since most ODB buildings were imported about a year ago, I don't expect an 
opposition from local mappers with reviewing that import.


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Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

Bonjour groupe,
The pre-processing procedure has been tested for the Squamish (BC) area. 
Squamish has a small number of buildings (6K) with a good Esri World imagery 
which need to be aligned with ODB data. A large number of ODB buildings show an 
inaccurate delineation (shaky drawing with too many nodes). Orthogonalization 
worked great but the result is not perfect because of the quality of the data. 
About 10% of the nodes were removed from the dataset. It contains all the 
problems we may encounter during this import. Consequently, I suggest that the 
import procedure be discussed and documented in detail using this case.
I could identify myself as the local import manager, but I would much prefer 
someone from the area to volunteer. When the local contributors have been 
contacted, and as long as there are no objections, we could start an import 
project in the OSMCanada task manager. Pre-processed data are available. We 
only have to make it available to the task manager. We also have to provide the 
task manager with the working areas (tasks) adjusted to 200 buildings per task. 
I am currently working to define these working areas, but if someone else can 
build it in the meantime it would be great.
Once the import project has been configured in the task manager, interested 
contributors will have to identify themselves in talk-ca in order to add them 
as authorized contributors (James, am I right?)
Would it be fun to try this?
Daniel

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Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

Hi all,
I was able to split Squamish into Quadtree tiles with a maximum of 200 
buildings each. James is now looking into whether/how this could be implemented 
in the task manager. If no one else is volunteering to be the local import 
manager this week, I will do the work and contact Squamish's local mappers. 
Since most ODB buildings were imported about a year ago, I don't expect an 
opposition from local mappers with reviewing that import.

Daniel
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Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

Bonjour groupe,
I should soon be able to feed the task manager with tiles containing no more 
than 200 buildings each.

I will be using a Quadtree algorithm similar to what was used to split Canvec 
map sheets. The problem is that the algorithm creates tiles that keep the 
aspect ratio of the data bounding box. I am currently modifying the algorithm 
to generate square tiles instead, which is much more adapted for editing with 
JOSM.

Daniel
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Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

In some cases, the aspect ratio is 1:5, creating long vertical tiles (tasks), 
or I may miss something :-)

Sent from Galaxy S7


From: Clifford Snow 
Sent: Saturday, February 15, 2020 5:36:19 PM
To: Daniel @jfd553 
Cc: Talk-CA OpenStreetMap 
Subject: Re: [Talk-ca] Importing buildings in Canada

I've done a number of building imports using no square shapes with no problem. 
JOSM is set to open up new tasks in a separate layer which avoid the problem of 
having task loading next the the just closed task. (I'm doing the imports in 
the US using voting districts. Each district typically has about 200-250 
houses. None of them are ever square. Perfect for an import.)

Best,
Clifford

On Sat, Feb 15, 2020 at 2:06 PM Daniel @jfd553 
mailto:jfd...@hotmail.com>> wrote:

Bonjour groupe,

I should soon be able to feed the task manager with tiles containing no more 
than 200 buildings each.



I will be using a Quadtree algorithm similar to what was used to split Canvec 
map sheets. The problem is that the algorithm creates tiles that keep the 
aspect ratio of the data bounding box. I am currently modifying the algorithm 
to generate square tiles instead, which is much more adapted for editing with 
JOSM.



Daniel

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--
@osm_washington
www.snowandsnow.us<https://www.snowandsnow.us>
OpenStreetMap: Maps with a human touch
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Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

Updates about the ODB import proposal
Documentation:
All the content regarding the current import has been moved to the Open 
Database of Building (ODB) wiki page [1]. The purpose of the page is now 
twofold. Provide a detailed procedure on how to import the data and to keep an 
inventory of what has been done/remains to do.
The Canada Building Import wiki page [2] will keep the same name but its 
content has been modified to serve as a hub for all building imports, previous 
and current. I also added a section to describe what best practices are when 
importing/editing buildings (to be developed).
Import:
Regarding the import, I proposed the import to be done using the task manager 
on a Municipal basis for all the reasons mentioned here [3]. In order to make 
it work properly, the OSMCanada task manager [4] needs to be set up for a given 
municipality only after a contributor has identified himself as the local 
import manager. We also know that the task manager us totally customizable [5].

Now we need to discuss, amongst other things, of ...

* Who will be in charge of setting up the task manager?

* What optimal task manager's parameters should be to ease the import?

* What parameters are required to review what has already been imported?

* How to proceed when pre-processing is required?
Proposals or suggestions? Let's discuss
Daniel

[1] https://wiki.openstreetmap.org/wiki/The_Open_Database_of_Buildings

[2] https://wiki.openstreetmap.org/wiki/Canada_Building_Import

[3] https://lists.openstreetmap.org/pipermail/talk-ca/2020-January/009541.html

[4] http://tasks.osmcanada.ca/

[5] https://lists.openstreetmap.org/pipermail/talk-ca/2020-January/009553.html


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[Talk-ca] FW: Re: Importing buildings in Canada

[Daniel @jfd553]

By the way, have a look at

https://wiki.openstreetmap.org/wiki/Canada_Building_Import

https://wiki.openstreetmap.org/wiki/The_Open_Database_of_Buildings
Cheers

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Re: [Talk-ca] FW: Re: Importing buildings in Canada

[Daniel @jfd553]

Bonjour Groupe,
Concerning the proposal (ODB import), there are questions that remain before 
moving forward; here are some of them...

a)  Who on this list host the ODB data? If pre-processing is required, how 
should we proceed to have the results made available (assuming I ran the 
pre-process)?

b)  Nate mentioned that the working units (shapes) proposed by the task 
manager are customizable according to data density. So, how many buildings can 
be imported properly (i.e. following the procedure) in an hour or so? Would it 
be a good size to proceed?

c)   There are areas where the data has already been imported. What would 
be the size of an import check task? I expect that a much larger number of 
buildings can be checked in an hour or so, but by how much (10x)?

d)  Who should be contacted when trying to get the local mappers buy-in? 
IMHO I would contact only those found by Pascal Neis' tool [1], which would 
have contributed more than 10 changesets and for which the main activity centre 
is within a the concerned municipality (tick/untick the display option boxes 
[1]).
Proposals or comments you which to share?
Daniel
[1] Overview of OpenStreetMap Contributors aka Who's around me? 
http://resultmaps.neis-one.org/oooc?
From: Daniel @jfd553 [mailto:jfd...@hotmail.com]
Sent: Saturday, January 11, 2020 15:41
To: talk-ca@openstreetmap.org
Subject: [Talk-ca] FW: Re: Importing buildings in Canada

By the way, have a look at

https://wiki.openstreetmap.org/wiki/Canada_Building_Import

https://wiki.openstreetmap.org/wiki/The_Open_Database_of_Buildings
Cheers

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Re: [Talk-ca] FW: Re: Importing buildings in Canada

[Daniel @jfd553]

Thanks for the quick replies!
Now, about...
a) Data hosting:
Thank you James, I really appreciate your offer (and that of others). So yes, I 
think hosting pre-processed data in the task manager, for approved regions, is 
an attractive offer. When we agree on a municipality for pre-processing, I will 
contact you to make the data available.
BTW, I thought ODB data in OSM format was hosted with the OSMCanada task 
manager. I understand that ODB data are currently converted on the fly when 
requested?
b) Task manager work units for import:
I agree with Nate, ~ 200 buildings or ~ 1,500 nodes would be suitable. I was 
thinking at the same importation rate, but for an hour of work. It seems best 
to target 20-minute tasks.
c) Task manager work units for checking already imported data
According to Nate, it is definitely not faster than actively importing. We 
should then keep the above setup (b).
However, what if I add a new tag to pre-processed data indicating if a building 
was altered or not by the orthogonalization (and simplification) process? For 
instance, building:altered=no, would identify buildings that were not changed 
by the process and that could be left unchanged in OSM (i.e. not imported); 
building:altered=yes for those who were changed by the process and that should 
be imported again. The same pre-processed datasets could then be made available 
for all cases. Thoughts?
d) Finding local mappers:
I agree with Nate's suggestion to try contacting the top 10 mappers in an area. 
Using the "main activity center" would work for most of the contributors but 
selecting other overlays (.e.g. an activity center over last 6 months) could 
also work great. As long as we identify who might be interested in knowing 
there is an import coming.
Comments are welcome, particularly about the proposal on c)
Daniel

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Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

Hi John, Tim, and the others :-)
John, I understand your concern and if it was not addressed properly, this 
could block the import again.

IMHO, we just need to make sure that we have done everything reasonable to 
inform the concerned contributors, in order to discuss the import in case they 
do not agree with it. That is why I proposed the following, in a previous 
email, concerning local mappers buy-in…

1- We contact them to explain our intentions by referring to the appropriate 
wiki pages.
2- We wait a week or two for them to respond to nothing, have concerns or want 
to help.
3- Without negative answers, we could proceed to the import.

The point 3 above make sure the project is not stalled in case there is no or 
only a few answers. The identification of local contributors using Neis’ tool, 
or the query Tim Elrick just proposed, are what I consider reasonable attempts 
for contacting the local mappers.

Daniel

-Original Message-
From: Tim Elrick via Talk-ca [mailto:talk-ca@openstreetmap.org] 
Sent: Wednesday, January 15, 2020 15:12
To: talk-ca@openstreetmap.org
Subject: Re: [Talk-ca] Importing buildings in Canada

Hi all,

*a) data hosting*
I can offer to host pre-processed data for the building imports as well.

*b) task manager work units*
I find smaller tasks about 20 minutes each more appealing than 1 hour tasks

*c) checking already existing data*
An added tag would certainly help as you can apply a filter in JOSM then.

*d) finding local mappers*
You can use the following query on http://overpass-turbo.eu/ to get a 
list of all users in the time period specified in the area specified.

// overpass query
[out:csv(::user)];
// replace Montreal by any known location in OSM, or see code below
// for bounding box use
{{geocodeArea:Montreal}}->.searchArea;
(
   // I collected users active in the last 6 months, but you can
   // change that
   node(newer:"{{date:6 months}}")(area.searchArea);
   way(newer:"{{date:6 months}}")(area.searchArea);
   relation(newer:"{{date:6 months}}")(area.searchArea);
);
out meta;
// end overpass query

Copy the query into the left side of the window and click Export, then 
'raw data directly from Overpass API'. This will generate a csv. You can 
then count the number of times a name appears in your list by using 
LibreOffice, R, Python or Excel. This will give you the number of 
objects a user entered in the last 6 months.

If I do this for Montreal I end up with 106 names who have contributed 
20 objects or more in the last half year or 46 names who have 
contributed 100 objects and more.

You can then use https://www.openstreetmap.org/message/new/USERNAME by 
replacing USERNAME with the names from the list to contact these users.

For areas where there is no geocodeArea in OSM you can use the 
boundingbox query below. First, zoom to the area of interest (i.e. your 
bounding box), then paste the following code on the left and export:

// overpass query
[out:csv(::user)];
(
   node(newer:"{{date:6 months}}")({{bbox}});
   way(newer:"{{date:6 months}}")({{bbox}});
   relation(newer:"{{date:6 months}}")({{bbox}});
);
out meta;
// end overpass query

Tim

On 2020-01-15 12:55, Daniel @jfd553 wrote:
Thanks for the quick replies!

Now, about...

*a) Data hosting:*

Thank you James, I really appreciate your offer (and that of others). So
yes, I think hosting pre-processed data in the task manager, for
approved regions, is an attractive offer. When we agree on a
municipality for pre-processing, I will contact you to make the data
available.

BTW, I thought ODB data in OSM format was hosted with the OSMCanada task
manager. I understand that ODB data are currently converted on the fly
when requested?

*b) Task manager work units for import:*

I agree with Nate, ~ 200 buildings or ~ 1,500 nodes would be suitable. I
was thinking at the same importation rate, but for an hour of work. It
seems best to target 20-minute tasks.

*c) Task manager work units for checking already imported data*

According to Nate, it is definitely not faster than actively importing.
We should then keep the above setup (b).

However, what if I add a new tag to pre-processed data indicating if a
building was altered or not by the orthogonalization (and
simplification) process? For instance, /building:altered=no/, would
identify buildings that were not changed by the process and that could
be left unchanged in OSM (i.e. not imported); /building:altered=yes/ for
those who were changed by the process and that should be imported again.
The same pre-processed datasets could then be made available for all
cases. Thoughts?

*d) Finding local mappers:*

I agree with Nate’s suggestion to try contacting the top 10 mappers in
an area. Using the "main activity center" would work for most of the
contributors but selecting other overlays (.e.g. an activity center over
last 6 months) could also work great. As long as we identif

Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

The page "The Open Database of Buildings" has been moved to the "Canada - The 
Open Database of Buildings" not to confuse wiki users from outside the country 
(a Tim Elrick suggestion).

Tim also identified another way to identify local mappers. I added a link to 
his recipe in the above wiki page, in "Get local buy-in before importing" 
section.

Daniel

-Original Message-
From: Tim Elrick [mailto:o...@elrick.de] 
Sent: Wednesday, January 15, 2020 17:19
To: Daniel @jfd553; john whelan
Cc: talk-ca@openstreetmap.org
Subject: Re: [Talk-ca] Importing buildings in Canada

Hi all,

I understand your concerns, John. However, many mappers might not follow 
talk-ca. So, I guess, Daniel's suggestion to contact them, might work 
better than waiting for them to incidentally check talk-ca.

* More to finding local mappers *
By providing the overpass query I just wanted to share a different way 
of contacting active mappers in your area. The advantage of Pascal's 
Who's around me is that you can see the mappers with lots of changesets, 
ie. presumably experienced mappers. The disadvantage is that these 
changesets do not have to be from the area we are interested in 
(however, with activity center in the last 6 months we at least make 
sure they were working in our area); another disadvantage is that you 
cannot collect the names of the mappers easily (or am I missing 
something here?). The advantage of the overpass query is that you get 
that list of names easily and you can see how many objects they have 
added in your area in the past months. The disadvantage, of course, is 
that we don't know how experienced the mappers are (but maybe this 
doesn't matter).

Anyway, either approach works as Daniel already pointed out. Thanks to 
stevea, I now know that I can share Overpass queries easily:
for a geocoded area:
http://overpass-turbo.eu/s/PM9
for a bounding box:
http://overpass-turbo.eu/s/PMb

* Contacting local mappers *
I suggest we design a template letter on the wiki page that can be send 
out to local mappers that include the everything that Daniel suggested 
in his last message below.

Tim


On 2020-01-15 15:54, Daniel @jfd553 wrote:
Hi John, Tim, and the others :-)
John, I understand your concern and if it was not addressed properly, 
this could block the import again.

IMHO, we just need to make sure that we have done everything reasonable 
to inform the concerned contributors, in order to discuss the import in 
case they do not agree with it. That is why I proposed the following, in 
a previous email, concerning local mappers buy-in…

1- We contact them to explain our intentions by referring to the 
appropriate wiki pages.
2- We wait a week or two for them to respond to nothing, have concerns 
or want to help.
3- Without negative answers, we could proceed to the import.

The point 3 above make sure the project is not stalled in case there is 
no or only a few answers. The identification of local contributors using 
Neis’ tool, or the query Tim Elrick just proposed, are what I consider 
reasonable attempts for contacting the local mappers.

Daniel

-Original Message-
From: Tim Elrick via Talk-ca [mailto:talk-ca@openstreetmap.org]
Sent: Wednesday, January 15, 2020 15:12
To: talk-ca@openstreetmap.org
Subject: Re: [Talk-ca] Importing buildings in Canada

Hi all,

*a) data hosting*
I can offer to host pre-processed data for the building imports as well.

*b) task manager work units*
I find smaller tasks about 20 minutes each more appealing than 1 hour tasks

*c) checking already existing data*
An added tag would certainly help as you can apply a filter in JOSM then.

*d) finding local mappers*
You can use the following query on http://overpass-turbo.eu/ to get a
list of all users in the time period specified in the area specified.

// overpass query
[out:csv(::user)];
// replace Montreal by any known location in OSM, or see code below
// for bounding box use
{{geocodeArea:Montreal}}->.searchArea;
(
 // I collected users active in the last 6 months, but you can
 // change that
 node(newer:"{{date:6 months}}")(area.searchArea);
 way(newer:"{{date:6 months}}")(area.searchArea);
 relation(newer:"{{date:6 months}}")(area.searchArea);
);
out meta;
// end overpass query

Copy the query into the left side of the window and click Export, then
'raw data directly from Overpass API'. This will generate a csv. You can
then count the number of times a name appears in your list by using
LibreOffice, R, Python or Excel. This will give you the number of
objects a user entered in the last 6 months.

If I do this for Montreal I end up with 106 names who have contributed
20 objects or more in the last half year or 46 names who have
contributed 100 objects and more.

You can then use https://www.openstreetmap.org/message/new/USERNAME by
replacing USERNAME with the names from the list to contact these users.

For areas where there i

Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

Bonjour groupe,
Here is a sequential summary of the last exchanges. I inserted some comments 
[…] within these exchanges description and summarize what I understand from it 
at the end.
Nate asked not to confuse the process of importing new data with that of 
updating/modifying existing OSM data in order to keep things simple for this 
import.
Daniel (I) responded that importing new data and updating/modifying existing 
ones at the same time (when necessary) is not unusual in OSM [and would be more 
efficient].
John replied that importing new data and updating/modify existing data when 
required worked quite nicely when importing Ottawa.
Nate explained he believes that the buildings will not be compared manually 
since there are hundreds of thousands of them in OSM for Toronto alone. In 
other words, he thinks there will be automated edits, and these edits are not 
governed by the same policies as imports. [This is an important consideration. 
What has happened in Ottawa and Toronto so far? Have automatic processes been 
used?]
Tim replied that in most cases it might be appropriate to replace OSM data, as 
he believes [as I do for most of the cases] that the ODB footprints will be 
more accurate than existing buildings. However he considers it is a 
case-by-case decision [then no automation process should be used].
John couldn’t resist digressing toward the “Microsoft buildings import” but had 
to bring back the discussion on ODB import after reactions from Tim and Pierre 
(LOL).

I think that, somehow, we could all agree on how the import should be done:

-  Align images on ODB, unless evidence ODB data are ill located.

-  Align existing OSM content with the image, only if necessary after 
aligning the image with ODB.

-  Import non-existent buildings in OSM.

-  Conflate ODB and OSM buildings, only if necessary.

-
To address Nate’s legitimate concerns, we could agree that there will be no 
automatic changes/conflation of existing buildings. Having a local import 
manager and by using the task manager, we should be able to ensure that there 
will be no unauthorized import (i.e. not responding to the above).
Am I too optimistic?
Daniel


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Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

Bonjour groupe!
Well, I think we are having a good discussion and are moving towards an import 
procedure with which everyone will be comfortable.
First, I have modified the wiki to reflect our latest discussion [1-3]. The 
import procedure seems to fit with current discussion. Please, have a look.
Second, about OSM vs. ODB data quality (Nate’s concern). Accuracy is a complex 
subject because it has multiple aspects. I examined [4] the completeness of the 
ODB and OSM buildings, the accuracy of the boundaries and the accuracy of the 
location, for all of the municipalities covered by the ODB dataset. Here is a 
summary of what I saw.
Data Completeness: Completeness of ODB buildings is generally much better than 
OSM, except when an import has already taken place (it is then similar), or for 
Sherbrooke and Nova Scotia (except for Halifax) areas.
Delineation accuracy: ODB buildings often have a better delineation than the 
OSM (e.g. right angles, level of detail) but it is far from being always the 
case. In some cases, which seem to depend on the census subdivision, OSM will 
have better building representation most of the time.
Location accuracy: Image requirements for municipal mapping are generally very 
high in order to properly manage their infrastructure (i.e. image resolution, 
ground control accuracy, DEM accuracy). Even if they use bounding boxes to 
represent buildings, the location of the resulting shapes is accurate. In the 
case of OSM, the images on which we delimit buildings footprints show very 
different accuracy, which leads to inconsistent location accuracy for all the 
features delineated over the imagery. Read above for more details [5].
Third, about who could contribute to the import? The presence of a local import 
manager should make it possible to assess the nature of the work done. I 
suggested to those who want to be a local import manager to share their 
intentions on Talk-ca. This means that we all know that “John Doe” will be 
responsible for importing “Lost City” before identifying him on the wiki page 
[4]. Only then should the project appear in the task manager. I also think that 
anyone who wishes to contribute should indicate their intentions on the list, 
so that their name can be added to those who are authorized to access the 
import tasks.
Comment, suggestions?
Daniel
-

[1] https://wiki.openstreetmap.org/wiki/Canada_Building_Import#Building_Imports

[2] 
https://wiki.openstreetmap.org/wiki/Canada_-_The_Open_Database_of_Buildings#Import_the_Data

[3] 
https://wiki.openstreetmap.org/wiki/Canada_-_The_Open_Database_of_Buildings#Import_Procedure

[4] 
https://wiki.openstreetmap.org/wiki/Canada_-_The_Open_Database_of_Buildings#Import_Status
[5] OSM buildings (imported or not) were all delimited by images (using ortho 
or stereo images). The accuracy of the images depends on the derived/available 
elevations in the area. Municipal mapping (i.e. ODB data origin) requires high 
location accuracy to manage municipal infrastructure. In OSM, the available 
ortho-images are created using DEM, the accuracy of which differs considerably. 
On flat surfaces, this does not matter (the only effect is generally seen on 
roofs which may have an offset from building footprint location on the ground). 
This is completely different on hilly areas where the resulting images will 
show offsets that change with elevations.


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Re: [Talk-ca] Importation de bâtiments de la Ville de Montréal

[Daniel @jfd553]

Hello Tim,
Your proposal to use data from the city of Montreal, rather than that of 
StatCan (ODB), is interesting but from my point of view, it is another data 
import project because of…
- Different licence [1]
- Different pre-processing [2]
- Different data description [3]

I propose you build an import proposal (Montreal Import) that will document all 
of the above. The Canada Building Import wiki page has been modified to easily 
include such proposal, in order not to mix it with current discussion (ODB 
import).

We can decide not to import Montreal data within the current ODB import. 
Identifying a local import manager and using the task manager ease the control 
of such management. Once your proposal fully documented, we could process the 
same way as we will do for ODB. 

[1] The licence should be documented here: 
https://wiki.openstreetmap.org/wiki/Canada_Building_Import#Compatible_Licences
[2] In addition to the pre-treatments already planned for ODB, it includes the 
potential integration of individual building separators (in another file or the 
estimation of these separators by software analysis).
[3] The import of topologically related buildings (former terraces) with 
potentially 3D information may require different editing rules when importing.

-Original Message-
From: Tim Elrick [mailto:o...@elrick.de] 
Sent: Sunday, January 12, 2020 18:01
To: Talk-CA OpenStreetMap
Subject: [Talk-ca] Importation de bâtiments de la Ville de Montréal

Bonjour à tous, surtout à Montréal,

Comme la discussion sur les importations de bâtiments au Canada reprend 
de plus belle, je voulais lancer la discussion au niveau local comme une 
retombée de la discussion principale sur talk-ca.

J'ai essayé de poster cela sur la liste de Montréal il y a une semaine, 
mais je n'ai pas pu joindre notre modérateur ni mes autres contacts. 
C'est pourquoi je commence maintenant la discussion ici.

*Source des données pour l'importation*
Je suggérerais de suivre plus ou moins l'importation du bâtiment comme 
décrit sur la page principale du wiki. Cependant, je suggérerais 
d'utiliser les données ouvertes de la Ville de Montréal (puisque nous 
avons le consentement de la Ville pour le faire [1]; comme Simon du LWG 
l'a déclaré ici [2], cela devrait être suffisant pour l'utiliser pour 
l'importation). Je le suggère pour deux raisons : lorsque StatCan a 
produit le jeu de données BDOI, il visait un jeu de données cohérent 
dans tout le Canada. C'est pourquoi il manque à BDOI l'information sur 
la hauteur des bâtiments (1).  De plus, il ne contient que les bâtiments 
confondus lorsqu'il y a des maisons en terrasse. Les séparateurs de 
bâtiments individuels sont fournis par la Ville de Montréal, mais dans 
un autre fichier shapefile. StatCan ne les a pas utilisés pour séparer 
les bâtiments. Par conséquent, nous obtiendrions des bâtiments de 
qualité inférieure lorsque nous utiliserions le BDOI (2). En dehors de 
cela, le BDOI est basé sur les données ouvertes de la Ville. Je suggère 
donc d'utiliser les données de la Ville de Montréal. Cela nous a permis 
aussi d'utiliser les empreintes des bâtiments pour créer des modèles 3D 
plus tard.

*Prétraitement nécessaire des données*
Les empreintes des bâtiments de la ville sont de très haute qualité car 
elles ont été dérivées d'images aériennes. Cependant, nous avons encore 
besoin de pré-traiter les données comme suggéré sur la page wiki. En 
outre, nous aurions aussi besoin d'inclure une étape supplémentaire :
la séparation des blocs de construction en bâtiments. À mon avis, les 
bâtiments devraient exister en tant que bâtiments individuels dans OSM, 
et non en tant qu'éléments des blocs. Il faut donc trouver un moyen de 
les séparer. Je sais que les cartographes d'OSM d'Ottawa n'ont pas pris 
la peine de séparer les maisons mitoyennes en bâtiments uniques et ça me 
va. Mais, je pense que cela ne suit pas le principe de la vérité de 
terrain (ground truth) et je suggère de le faire de cette façon à 
Montréal. Nous pouvons soit rechercher une automatisation de cette étape 
par FME, PostGreSQL/PostGIS, QGIS ou le faire manuellement. J'ai déjà 
regardé un peu et j'ai trouvé que c'est assez complexe car il y a 
beaucoup d'exceptions. La simplification (suppression des nœuds 
superflus) pourrait bien fonctionner avec un outil automatisé. J'ai des 
doutes sur la division des bâtiments individuels ainsi que sur 
l'orthogonalisation des maisons mitoyennes.

Qu'est-ce que vous en pensez ?

Allons-y !

Bonne journée,
Tim

+++
AGeographer sur OSM

[1] 
https://wiki.openstreetmap.org/wiki/Montr%C3%A9al/Imports/Ville_de_Montr%C3%A9al
[2] https://blog.openstreetmap.org/2017/03/17/use-of-cc-by-data/

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Re: [Talk-ca] FW: Re: Importing buildings in Canada

[Daniel @jfd553]

Hello Nate,
I understand that you don't like to see an import process that both bring in 
new objects and overwrite existing ones. You also suggest removing "overlapped" 
building from ODB prior to import it. Such pre-processing, that would ensure 
there will be no buildings "overwrite" during the import, is not realistic 
(i.e. you will need to overwrite some buildings anyway). Here are two reasons 
why it would be difficult...

1-  OSM is a dynamic project and, unless you can "clean" the data on the 
fly, you will end up with overlaps since some contributors will have added 
buildings in the meantime.

2-  One cannot assume that an OSM building, and its ODB counterpart, will 
be found at the same location (look at DX and DY columns in ODB inventory 
tables). These are averages, which means there are larger offsets between both 
datasets (i.e. you won't get a match between buildings, or get a match with the 
wrong ones).
The only realistic option is then to manually delete the ODB buildings if they 
overlap OSM ones. Here is what the import guideline suggests [1]...

"If you are importing data where there is already some data in OSM, then you 
need to combine this data in an appropriate way or suppress the import of 
features with overlap with existing data."
Therefore, importing data and using a conflation process is not unusual. Again, 
I understand that in case of an overlap, you go for the last option (suppress 
the import building). I am rather inclined toward using conflation when 
necessary, which means...

-  Importing an ODB building when there is no corresponding one in OSM;

-  Conflating both ODB and OSM buildings when it significantly improves 
existing OSM content;

-  Not importing an ODB building when the corresponding one in OSM is 
adequate.
What do the others on the list think?
Daniel
[1] 
https://wiki.openstreetmap.org/wiki/Import/Guidelines#Don.27t_put_data_on_top_of_data


From: Nate Wessel [mailto:bike...@gmail.com]
Sent: Thursday, January 16, 2020 10:38
To: Daniel @jfd553; talk-ca@openstreetmap.org
Subject: Re: [Talk-ca] FW: Re: Importing buildings in Canada


Responding to point C below,
I would strongly suggest that we not confuse the process of importing new data 
with that of updating/modifying existing data in the OSM database. One of the 
things I really disliked about the initial building import was that it 
overwrote existing data at the same time that new data was brought in. These 
are really two separate import processes and require very different 
considerations.

We can certainly consider using this dataset to improve/update existing 
building geometries, but I think that is a separate process from the import we 
are discussing here. To keep things simple for this import, I would suggest 
removing any building from the import dataset that intersects with an existing 
building in the OSM database. That is, let's not worry about conflation for 
now, and come back and do that work later if we still feel there is a strong 
need for it.

I see the main point of this effort as getting more complete coverage - it we 
want to use the dataset to do quality assurance on existing data, that is a 
whole other discussion.

Best,

Nate Wessel, PhD
Planner, Cartographer, Transport Nerd
NateWessel.com<https://www.natewessel.com>
On 2020-01-15 12:55 p.m., Daniel @jfd553 wrote:
Thanks for the quick replies!
Now, about...
a) Data hosting:
Thank you James, I really appreciate your offer (and that of others). So yes, I 
think hosting pre-processed data in the task manager, for approved regions, is 
an attractive offer. When we agree on a municipality for pre-processing, I will 
contact you to make the data available.
BTW, I thought ODB data in OSM format was hosted with the OSMCanada task 
manager. I understand that ODB data are currently converted on the fly when 
requested?
b) Task manager work units for import:
I agree with Nate, ~ 200 buildings or ~ 1,500 nodes would be suitable. I was 
thinking at the same importation rate, but for an hour of work. It seems best 
to target 20-minute tasks.
c) Task manager work units for checking already imported data
According to Nate, it is definitely not faster than actively importing. We 
should then keep the above setup (b).
However, what if I add a new tag to pre-processed data indicating if a building 
was altered or not by the orthogonalization (and simplification) process? For 
instance, building:altered=no, would identify buildings that were not changed 
by the process and that could be left unchanged in OSM (i.e. not imported); 
building:altered=yes for those who were changed by the process and that should 
be imported again. The same pre-processed datasets could then be made available 
for all cases. Thoughts?
d) Finding local mappers:
I agree with Nate's suggestion to try contacting the top 10 mappers in an area. 
Using the "main activity center" woul

Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

Bonjour groupe, mes excuses pour ce très long courriel !-)
I have reviewed everything that has been written on the ODB import (aka Canada 
Building Import) in Talk-ca and the wiki. I proposed changes to some wiki pages 
(via talk tabs) to ease the discussions about this import and the following. 
Now, in order to restart the import, here are some thoughts and a proposal on 
how to proceed to complete the task.

1. Issues with the ODB Data Import
Many concerns were raised about the import. One major concern was to obtain 
local communities' buy-in in the Canadian context. Another concern was to 
improve the quality of the data prior the import. The following paragraphs 
intend to clear most of these concerns.
1.1. Which data import project?
According to the import guidelines (steps 3 & 4), a data import explicitly 
refers to a single data source (ODB in our case). Discussions about the 
availability and quality of Microsoft or ESRI data, while interesting, are not 
relevant as they should be dealt with as other import projects.
1.2. What has been imported so far?
According to what I found [1], the ODB import is completed for 21 
municipalities. These imports seem to have kept OSM content's history, at least 
for the samples checked, but many problems were found. In some case, the 
imports brought swimming pools in OSM because they were included in the dataset 
(e.g. Moncton). In other cases, importing buildings with accurate locations 
(XY) over content mapped from less accurate imagery resulted in buildings that 
now overlap the street network (e.g. Squamish). It means that all these 21 
imports need to be carefully re-examined and corrected as required.
For 12 other municipalities, the import is partial, either suspended as 
requested, or because previous imports had already provided most of the 
buildings (often from the same municipal provider). That said the import will 
definitely improve OSM accuracy and completeness if done properly.
2. How should ODB Data be imported?
I will copy the following paragraphs in the "Canada Building Import" wiki page 
[3] for a detailed discussion...
Since the data (ODB, OSM and imagery) differ from one municipality to another, 
there can be no imports at the national or provincial level. We have to work on 
a municipal basis and make sure to identify all the problems and the corrective 
measures to apply when dealing with issues like those I identified [1].
2.1 Importing Locally
According to the import guidelines (step 2), we must not import the data 
without local buy-in. However, and contrarily to some European country, there 
is usually no such thing as a local OSM community in each municipality. 
However, we may find a few local mappers from time to time. Working on a 
municipal basis should allow identifying these local mappers before doing the 
import. I often use this tool [2] to identify and contact local mappers. Once 
identified, I suggest that...
- We contact them to explain our intents by referring to appropriate wiki pages.
- We wait a week or two to let them respond nothing, that they have concerns, 
or wish to help.
- Without negative answers we could proceed to the import.
I first suggest that when a contributor wishes to import ODB for a given 
municipality, he first identifies himself as responsible for the import (we 
need to create an entry for each municipality somewhere in the wiki). He can 
then contact local mappers, as explain above, and go ahead with the import once 
everything settled. For those who already made the import, I suggest that they 
review their work since many issues were detected with some of these imports.
Since there are only a few local OSM communities in Canada, and because Canada 
is large, I suggest not limiting the import of a given municipality to the 
people of the concerned province or region.
2.2 Pre-processing
Once local mappers have agreed, some pre-processing can be done if required.
A few months ago, I developed a tool that could be used to process the data 
[4]. Concerns were raised because the application was developed using 
proprietary software. So I documented the whole process and algorithms in order 
to see courageous coders converting it in open source software. In the 
meantime, and as long as I have access to an FME licence, I could process the 
data, when necessary, prior to make it available through the task manager.
Proposed pre-processing [4] includes:
- Reading of original ODB data,
- Removal of near collinear nodes (simplification),
- Orthogonalization of buildings (for corners having near right angles),
- Tagging of building footprints,
- Providing files in OSM format.
Proposed tagging: In addition to the tags produced by the orthogonalization 
process [4] and the source tag 
(source=Statistics Canada - 
Open Building Database), the name of the Census Subdivision provided in ODB 
data [5] is used to add the addr:city tag to each building.
The 

Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

That is why I proposed changes in some wiki page (talk), to deal with many 
imports, without mixing discussions :-)

Daniel

From: Daniel @jfd553 [mailto:jfd...@hotmail.com]
Sent: Friday, January 03, 2020 16:06
To: john whelan; Daniel @jfd553
Cc: talk-ca@openstreetmap.org
Subject: RE: [Talk-ca] Importing buildings in Canada

Hi John,
To comply with the import directive, I would like the discussion to continue on 
the current ODB import only. Could we talk about other sources of potential 
imports at another time? -)

Thanks
Daniel
From: john whelan [mailto:jwhelan0...@gmail.com]
Sent: Friday, January 03, 2020 15:57
To: Daniel @jfd553
Cc: talk-ca@openstreetmap.org
Subject: Re: [Talk-ca] Importing buildings in Canada

Sounds sane to me.

Are we thinking of setting up a second import to handle Microsoft building 
outlines on a similar basis? Or extending this one?  I only ask since if we are 
doing it municipality by municipality it might be an idea to identify those 
municipalities that do not have suitable open data through stats canada.  I can 
see us with a list of municipalities and a data source and I think it probably 
should be in one place.

Cheerio John

On Fri, 3 Jan 2020 at 15:42, Daniel @jfd553 
mailto:jfd...@hotmail.com>> wrote:
Bonjour groupe, mes excuses pour ce très long courriel !-)
I have reviewed everything that has been written on the ODB import (aka Canada 
Building Import) in Talk-ca and the wiki. I proposed changes to some wiki pages 
(via talk tabs) to ease the discussions about this import and the following. 
Now, in order to restart the import, here are some thoughts and a proposal on 
how to proceed to complete the task.

1. Issues with the ODB Data Import
Many concerns were raised about the import. One major concern was to obtain 
local communities’ buy-in in the Canadian context. Another concern was to 
improve the quality of the data prior the import. The following paragraphs 
intend to clear most of these concerns.
1.1. Which data import project?
According to the import guidelines (steps 3 & 4), a data import explicitly 
refers to a single data source (ODB in our case). Discussions about the 
availability and quality of Microsoft or ESRI data, while interesting, are not 
relevant as they should be dealt with as other import projects.
1.2. What has been imported so far?
According to what I found [1], the ODB import is completed for 21 
municipalities. These imports seem to have kept OSM content’s history, at least 
for the samples checked, but many problems were found. In some case, the 
imports brought swimming pools in OSM because they were included in the dataset 
(e.g. Moncton). In other cases, importing buildings with accurate locations 
(XY) over content mapped from less accurate imagery resulted in buildings that 
now overlap the street network (e.g. Squamish). It means that all these 21 
imports need to be carefully re-examined and corrected as required.
For 12 other municipalities, the import is partial, either suspended as 
requested, or because previous imports had already provided most of the 
buildings (often from the same municipal provider). That said the import will 
definitely improve OSM accuracy and completeness if done properly.
2. How should ODB Data be imported?
I will copy the following paragraphs in the “Canada Building Import” wiki page 
[3] for a detailed discussion…
Since the data (ODB, OSM and imagery) differ from one municipality to another, 
there can be no imports at the national or provincial level. We have to work on 
a municipal basis and make sure to identify all the problems and the corrective 
measures to apply when dealing with issues like those I identified [1].
2.1 Importing Locally
According to the import guidelines (step 2), we must not import the data 
without local buy-in. However, and contrarily to some European country, there 
is usually no such thing as a local OSM community in each municipality. 
However, we may find a few local mappers from time to time. Working on a 
municipal basis should allow identifying these local mappers before doing the 
import. I often use this tool [2] to identify and contact local mappers. Once 
identified, I suggest that…
- We contact them to explain our intents by referring to appropriate wiki pages.
- We wait a week or two to let them respond nothing, that they have concerns, 
or wish to help.
- Without negative answers we could proceed to the import.
I first suggest that when a contributor wishes to import ODB for a given 
municipality, he first identifies himself as responsible for the import (we 
need to create an entry for each municipality somewhere in the wiki). He can 
then contact local mappers, as explain above, and go ahead with the import once 
everything settled. For those who already made the import, I suggest that they 
review their work since many issues were detected with some of these imports.
Since there are only a few local OSM communities in Canada, and because Canada

Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

Hi John,
To comply with the import directive, I would like the discussion to continue on 
the current ODB import only. Could we talk about other sources of potential 
imports at another time? -)

Thanks
Daniel
From: john whelan [mailto:jwhelan0...@gmail.com]
Sent: Friday, January 03, 2020 15:57
To: Daniel @jfd553
Cc: talk-ca@openstreetmap.org
Subject: Re: [Talk-ca] Importing buildings in Canada

Sounds sane to me.

Are we thinking of setting up a second import to handle Microsoft building 
outlines on a similar basis? Or extending this one?  I only ask since if we are 
doing it municipality by municipality it might be an idea to identify those 
municipalities that do not have suitable open data through stats canada.  I can 
see us with a list of municipalities and a data source and I think it probably 
should be in one place.

Cheerio John

On Fri, 3 Jan 2020 at 15:42, Daniel @jfd553 
mailto:jfd...@hotmail.com>> wrote:
Bonjour groupe, mes excuses pour ce très long courriel !-)
I have reviewed everything that has been written on the ODB import (aka Canada 
Building Import) in Talk-ca and the wiki. I proposed changes to some wiki pages 
(via talk tabs) to ease the discussions about this import and the following. 
Now, in order to restart the import, here are some thoughts and a proposal on 
how to proceed to complete the task.

1. Issues with the ODB Data Import
Many concerns were raised about the import. One major concern was to obtain 
local communities’ buy-in in the Canadian context. Another concern was to 
improve the quality of the data prior the import. The following paragraphs 
intend to clear most of these concerns.
1.1. Which data import project?
According to the import guidelines (steps 3 & 4), a data import explicitly 
refers to a single data source (ODB in our case). Discussions about the 
availability and quality of Microsoft or ESRI data, while interesting, are not 
relevant as they should be dealt with as other import projects.
1.2. What has been imported so far?
According to what I found [1], the ODB import is completed for 21 
municipalities. These imports seem to have kept OSM content’s history, at least 
for the samples checked, but many problems were found. In some case, the 
imports brought swimming pools in OSM because they were included in the dataset 
(e.g. Moncton). In other cases, importing buildings with accurate locations 
(XY) over content mapped from less accurate imagery resulted in buildings that 
now overlap the street network (e.g. Squamish). It means that all these 21 
imports need to be carefully re-examined and corrected as required.
For 12 other municipalities, the import is partial, either suspended as 
requested, or because previous imports had already provided most of the 
buildings (often from the same municipal provider). That said the import will 
definitely improve OSM accuracy and completeness if done properly.
2. How should ODB Data be imported?
I will copy the following paragraphs in the “Canada Building Import” wiki page 
[3] for a detailed discussion…
Since the data (ODB, OSM and imagery) differ from one municipality to another, 
there can be no imports at the national or provincial level. We have to work on 
a municipal basis and make sure to identify all the problems and the corrective 
measures to apply when dealing with issues like those I identified [1].
2.1 Importing Locally
According to the import guidelines (step 2), we must not import the data 
without local buy-in. However, and contrarily to some European country, there 
is usually no such thing as a local OSM community in each municipality. 
However, we may find a few local mappers from time to time. Working on a 
municipal basis should allow identifying these local mappers before doing the 
import. I often use this tool [2] to identify and contact local mappers. Once 
identified, I suggest that…
- We contact them to explain our intents by referring to appropriate wiki pages.
- We wait a week or two to let them respond nothing, that they have concerns, 
or wish to help.
- Without negative answers we could proceed to the import.
I first suggest that when a contributor wishes to import ODB for a given 
municipality, he first identifies himself as responsible for the import (we 
need to create an entry for each municipality somewhere in the wiki). He can 
then contact local mappers, as explain above, and go ahead with the import once 
everything settled. For those who already made the import, I suggest that they 
review their work since many issues were detected with some of these imports.
Since there are only a few local OSM communities in Canada, and because Canada 
is large, I suggest not limiting the import of a given municipality to the 
people of the concerned province or region.
2.2 Pre-processing
Once local mappers have agreed, some pre-processing can be done if required.
A few months ago, I developed a tool that could be used to process the data 
[4]. Concerns were rais

Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

Bonjour groupe

Looks like we're going in the same direction so far :-)
I agree with Nate regarding the implementation of the task manager. In my 
experience, a size of a few blocks would be better in urban areas, but boring 
in rural areas. Is it something that can be adjusted?

Daniel

From: Nate Wessel [mailto:bike...@gmail.com]
Sent: Saturday, January 04, 2020 10:09
To: talk-ca@openstreetmap.org
Subject: Re: [Talk-ca] Importing buildings in Canada


Hi Daniel,

Thank you for all the work you've put into this. I'd like to offer a couple 
suggestions and/or clarifications for your proposed import process, overview 
though it is.

First, I think it is very important that a tasking manager is set up on a 
city/by city basis only, and that only AFTER consensus is achieved that the 
import should proceed in that area. I would really like to avoid seeing the 
massive nationwide tasking that was set up the first time around. We should be 
making it hard for people to go rogue in regions where consensus for an import 
doesn't (yet) exist.

Related to this, though important enough to be a second point in it's own 
right, the tasking squares need to be small enough that a single user can 
manage them and inspect every single building in a task. The first round of 
import used task squares that were massive, and which couldn't be divided any 
further past a certain point. Even in rural areas, it is likely inappropriate 
to import areas larger than 1km^2. In central Toronto it would be (and was) 
idiotic. An import that doesn't take local scale into account shouldn't 
proceed. "Too big to load into JOSM" is about 100x too big to import in my 
opinion and is not a good enough benchmark for import batch sizing.

That is, each import needs to be local, and not just in a superficial sense.

I'll also add that the issue of conflation doesn't seem to have been worked out 
yet except to note that it is an issue. What will we do with the millions of 
buildings which will substantially overlap/duplicate existing buildings or 
imports? This needs to be worked out in detail before anything starts up again.

And what needs to be done about already existing low quality imports? It's good 
to acknowledge their existence, but what will be done about them? We've set up 
a task to clean up some of the mess in Toronto ( 
http://tasks.osmcanada.ca/project/168 ) but this is only the tip of the iceberg.

Again, I thank everyone for their time and effort on this - we can get this 
done if we go slow and do it right :-)

Best,

Nate Wessel, PhD
Planner, Cartographer, Transport Nerd
NateWessel.com<https://www.natewessel.com>
On 2020-01-03 3:40 p.m., Daniel @jfd553 wrote:
Bonjour groupe, mes excuses pour ce très long courriel !-)
I have reviewed everything that has been written on the ODB import (aka Canada 
Building Import) in Talk-ca and the wiki. I proposed changes to some wiki pages 
(via talk tabs) to ease the discussions about this import and the following. 
Now, in order to restart the import, here are some thoughts and a proposal on 
how to proceed to complete the task.

1. Issues with the ODB Data Import
Many concerns were raised about the import. One major concern was to obtain 
local communities' buy-in in the Canadian context. Another concern was to 
improve the quality of the data prior the import. The following paragraphs 
intend to clear most of these concerns.
1.1. Which data import project?
According to the import guidelines (steps 3 & 4), a data import explicitly 
refers to a single data source (ODB in our case). Discussions about the 
availability and quality of Microsoft or ESRI data, while interesting, are not 
relevant as they should be dealt with as other import projects.
1.2. What has been imported so far?
According to what I found [1], the ODB import is completed for 21 
municipalities. These imports seem to have kept OSM content's history, at least 
for the samples checked, but many problems were found. In some case, the 
imports brought swimming pools in OSM because they were included in the dataset 
(e.g. Moncton). In other cases, importing buildings with accurate locations 
(XY) over content mapped from less accurate imagery resulted in buildings that 
now overlap the street network (e.g. Squamish). It means that all these 21 
imports need to be carefully re-examined and corrected as required.
For 12 other municipalities, the import is partial, either suspended as 
requested, or because previous imports had already provided most of the 
buildings (often from the same municipal provider). That said the import will 
definitely improve OSM accuracy and completeness if done properly.
2. How should ODB Data be imported?
I will copy the following paragraphs in the "Canada Building Import" wiki page 
[3] for a detailed discussion...
Since the data (ODB, OSM and imagery) differ from one municipality to another, 
there can be no imports at the national or provincial level. We have to work 

Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

Hi Group!
I am currently working on a proposal which, I hope, will bring consensus among 
the community and relaunch the import of ODB footprints (StatCan). The proposal 
should be ready in a few weeks, or sooner.

In the meantime, I suggest to all those who are interested to take note of the 
observations I made regarding these data. This information can be found in the 
OSM wiki (1). According to OSM import guideline requirements, it describes the 
data to import. At the same time, I updated the Canada-federal section of the 
Data Potential wiki page (2).

I will be offline in the next few days, so if you have any questions/comments, 
please be patient :-)

Daniel

1 - https://wiki.openstreetmap.org/wiki/The_Open_Database_of_Buildings
2 - 
https://wiki.openstreetmap.org/wiki/Potential_Datasources#Federal_.28Open_Government.29
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Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

I'll get back to you in a couple of days:-)

Sent from Galaxy S7


From: John Whelan 
Sent: Tuesday, December 24, 2019 6:21:06 PM
To: Daniel @jfd553 
Cc: James ; Talk-CA OpenStreetMap 

Subject: Re: [Talk-ca] Importing buildings in Canada

So an approach would be to pick off those areas with good data available first 
with few existing buildings mapped?

Such as Victoria or Courtenay in BC

Burlington, Caledon, Barrie in Ontario

Then move forward based on that experience?

I'd feel more comfortable with a mapper from the province at least coordinating 
the mapping even if there wasn't a local group.

How would we tackle places such as Perth? Smith Falls and Brockville which are 
available in Bing if not other sources?  These are in Ontario and fairly local 
to Ottawa by the way.

Thanks John

Daniel @jfd553 wrote on 2019-12-24 6:04 PM:
Have a look at the wiki page I referred to. Further discussions will be more 
easy and focused

Sent from Galaxy S7


From: John Whelan <mailto:jwhelan0...@gmail.com>
Sent: Tuesday, December 24, 2019 2:50:29 PM
To: James <mailto:james2...@gmail.com>
Cc: Daniel @jfd553 <mailto:jfd...@hotmail.com>; Talk-CA 
OpenStreetMap <mailto:talk-ca@openstreetmap.org>
Subject: Re: [Talk-ca] Importing buildings in Canada

I think the first problem to be addressed is the presence or absence of a local 
community.

In the north we have few mappers but lots of interested agencies and people in 
seeing the buildings imported.

Montreal I think is under control.  Toronto is in the process of sorting itself 
out but I'm unclear how much territory the Toronto local group covers.

Vancouver should be big enough to support a local group.  As should Calgary and 
Edmonton.

Ottawa is complete as is Gatineau.

It's the smaller cities and regions that would be my concern.  Often it will be 
by chance that two or more mappers meet occasionally.

So step one can we list the local groups?

I also have a problem with what happens if two people agree but haven't done 
any mapping are they a local group?

Step two to me would be a consensus on how to tackle those areas without a 
local group and I think Daniel's suggestion would be a way forward in this area.

Cheerio John



James wrote on 2019-12-24 1:28 PM:
wasn't there talk about this before and someone blocked it because of 
non-square buildings and the resulting discussion was that each community was 
going to decide if they want to import or not?

On Tue., Dec. 24, 2019, 1:26 p.m. Daniel @jfd553, 
mailto:jfd...@hotmail.com>> wrote:

Hi Group!

I am currently working on a proposal which, I hope, will bring consensus among 
the community and relaunch the import of ODB footprints (StatCan). The proposal 
should be ready in a few weeks, or sooner.



In the meantime, I suggest to all those who are interested to take note of the 
observations I made regarding these data. This information can be found in the 
OSM wiki (1). According to OSM import guideline requirements, it describes the 
data to import. At the same time, I updated the Canada-federal section of the 
Data Potential wiki page (2).



I will be offline in the next few days, so if you have any questions/comments, 
please be patient :-)



Daniel



1 - https://wiki.openstreetmap.org/wiki/The_Open_Database_of_Buildings

2 - 
https://wiki.openstreetmap.org/wiki/Potential_Datasources#Federal_.28Open_Government.29

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Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

Have a look at the wiki page I referred to. Further discussions will be more 
easy and focused

Sent from Galaxy S7


From: John Whelan 
Sent: Tuesday, December 24, 2019 2:50:29 PM
To: James 
Cc: Daniel @jfd553 ; Talk-CA OpenStreetMap 

Subject: Re: [Talk-ca] Importing buildings in Canada

I think the first problem to be addressed is the presence or absence of a local 
community.

In the north we have few mappers but lots of interested agencies and people in 
seeing the buildings imported.

Montreal I think is under control.  Toronto is in the process of sorting itself 
out but I'm unclear how much territory the Toronto local group covers.

Vancouver should be big enough to support a local group.  As should Calgary and 
Edmonton.

Ottawa is complete as is Gatineau.

It's the smaller cities and regions that would be my concern.  Often it will be 
by chance that two or more mappers meet occasionally.

So step one can we list the local groups?

I also have a problem with what happens if two people agree but haven't done 
any mapping are they a local group?

Step two to me would be a consensus on how to tackle those areas without a 
local group and I think Daniel's suggestion would be a way forward in this area.

Cheerio John



James wrote on 2019-12-24 1:28 PM:
wasn't there talk about this before and someone blocked it because of 
non-square buildings and the resulting discussion was that each community was 
going to decide if they want to import or not?

On Tue., Dec. 24, 2019, 1:26 p.m. Daniel @jfd553, 
mailto:jfd...@hotmail.com>> wrote:

Hi Group!

I am currently working on a proposal which, I hope, will bring consensus among 
the community and relaunch the import of ODB footprints (StatCan). The proposal 
should be ready in a few weeks, or sooner.



In the meantime, I suggest to all those who are interested to take note of the 
observations I made regarding these data. This information can be found in the 
OSM wiki (1). According to OSM import guideline requirements, it describes the 
data to import. At the same time, I updated the Canada-federal section of the 
Data Potential wiki page (2).



I will be offline in the next few days, so if you have any questions/comments, 
please be patient :-)



Daniel



1 - https://wiki.openstreetmap.org/wiki/The_Open_Database_of_Buildings

2 - 
https://wiki.openstreetmap.org/wiki/Potential_Datasources#Federal_.28Open_Government.29

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Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

Okey dokey :-)
Here is a short wrap-up about current discussion and questions raised so far, 
with some answers given from my perspective.
First a few definitions…
Municipality: Data_prov attribute in ODB data. It is the name of the 
municipality, region, or province/territory that provided the dataset. Each of 
these datasets usually covers many smaller cities, towns or villages as 
identified by the CSDNAME attribute in ODB data.
Local import manager: Someone that identified himself as responsible for the 
import in a given municipality. We will need an entry in the wiki to identify 
them. Following is a list of his/her potential responsibilities.
- He/she will ensure the whole import process respects the rules that we will 
put in place.
- He/she will attempt to contact local mappers, if any, to get a local buy-in.
- He/she will ask for pre-processing the data if required.
- He/she will ask for setting up the task manager for that municipality.
The local import manager is NOT responsible for doing the whole import, just 
ensuring that the process is done right (see Import Process paragraphs below).
Now some topics raised in the thread…
Importing locally - see proposal 2.1
- The proposal describes an approach that allows an import even where there are 
no local communities. As long as there is a local import manager, all available 
data should be imported (for urban and rural areas).
The Task Manager - see proposal 2.3 1-
- To make sure there in no wild import, an import task should be set-up only 
after a local import manager has required it. Without a local import manager, 
the data should not be made available through the task manager (i.e. NO import).
- Being able to adapt the size of the working squares in the task manager is 
great news. We just have to identify what could be a reasonable volume of 
building to process, let’s say in an hour, to adjust the squares accordingly.
The Import Process - see proposal 2.3 4-
- It would be fun if we all got involved in importing data as a municipality 
becomes available for import. We might all have local knowledge to share even 
if we do not live in a given municipality.
- The Conflation process is when you need to replace the geometry of an 
existing OSM building with the one from ODB data because it would significantly 
be improved. Consequently, not all buildings need to be changed using ODB data.
Correction of already imported data - see proposal 2.3 2-, 3-
- Identifying those who carried out these imports as de facto responsible for 
the corrections might seem like blame in some case. I suggest that anyone could 
identify themselves as local import manager for concerned municipalities, 
including those who made the first import if they wish.
- Correction might be twofold: the correction of low quality building shapes 
and the correction of low positional accuracy of OSM content when it is the 
case.



Thanks for your interest!

Daniel

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Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

Cool, thanks!

Sent from Galaxy S7


From: Nate Wessel 
Sent: Sunday, January 5, 2020 11:40:10 AM
To: Daniel @jfd553 ; talk-ca@openstreetmap.org 

Subject: Re: [Talk-ca] Importing buildings in Canada


The task size, and even shape is totally customizable. I've set up a couple 
that are entirely based on the density of the data:
http://tasks.osmcanada.ca/project/168
https://tasks.openstreetmap.us/project/107

Best,

Nate Wessel, PhD
Planner, Cartographer, Transport Nerd
NateWessel.com<https://www.natewessel.com>

On 2020-01-04 12:40 p.m., Daniel @jfd553 wrote:

Bonjour groupe



Looks like we're going in the same direction so far :-)

I agree with Nate regarding the implementation of the task manager. In my 
experience, a size of a few blocks would be better in urban areas, but boring 
in rural areas. Is it something that can be adjusted?



Daniel



From: Nate Wessel [mailto:bike...@gmail.com]
Sent: Saturday, January 04, 2020 10:09
To: talk-ca@openstreetmap.org<mailto:talk-ca@openstreetmap.org>
Subject: Re: [Talk-ca] Importing buildings in Canada



Hi Daniel,

Thank you for all the work you've put into this. I'd like to offer a couple 
suggestions and/or clarifications for your proposed import process, overview 
though it is.

First, I think it is very important that a tasking manager is set up on a 
city/by city basis only, and that only AFTER consensus is achieved that the 
import should proceed in that area. I would really like to avoid seeing the 
massive nationwide tasking that was set up the first time around. We should be 
making it hard for people to go rogue in regions where consensus for an import 
doesn't (yet) exist.

Related to this, though important enough to be a second point in it's own 
right, the tasking squares need to be small enough that a single user can 
manage them and inspect every single building in a task. The first round of 
import used task squares that were massive, and which couldn't be divided any 
further past a certain point. Even in rural areas, it is likely inappropriate 
to import areas larger than 1km^2. In central Toronto it would be (and was) 
idiotic. An import that doesn't take local scale into account shouldn't 
proceed. "Too big to load into JOSM" is about 100x too big to import in my 
opinion and is not a good enough benchmark for import batch sizing.

That is, each import needs to be local, and not just in a superficial sense.

I'll also add that the issue of conflation doesn't seem to have been worked out 
yet except to note that it is an issue. What will we do with the millions of 
buildings which will substantially overlap/duplicate existing buildings or 
imports? This needs to be worked out in detail before anything starts up again.

And what needs to be done about already existing low quality imports? It's good 
to acknowledge their existence, but what will be done about them? We've set up 
a task to clean up some of the mess in Toronto ( 
http://tasks.osmcanada.ca/project/168 ) but this is only the tip of the iceberg.

Again, I thank everyone for their time and effort on this - we can get this 
done if we go slow and do it right :-)

Best,

Nate Wessel, PhD
Planner, Cartographer, Transport Nerd
NateWessel.com<https://www.natewessel.com>

On 2020-01-03 3:40 p.m., Daniel @jfd553 wrote:

Bonjour groupe, mes excuses pour ce très long courriel !-)

I have reviewed everything that has been written on the ODB import (aka Canada 
Building Import) in Talk-ca and the wiki. I proposed changes to some wiki pages 
(via talk tabs) to ease the discussions about this import and the following. 
Now, in order to restart the import, here are some thoughts and a proposal on 
how to proceed to complete the task.



1. Issues with the ODB Data Import

Many concerns were raised about the import. One major concern was to obtain 
local communities’ buy-in in the Canadian context. Another concern was to 
improve the quality of the data prior the import. The following paragraphs 
intend to clear most of these concerns.

1.1. Which data import project?

According to the import guidelines (steps 3 & 4), a data import explicitly 
refers to a single data source (ODB in our case). Discussions about the 
availability and quality of Microsoft or ESRI data, while interesting, are not 
relevant as they should be dealt with as other import projects.

1.2. What has been imported so far?

According to what I found [1], the ODB import is completed for 21 
municipalities. These imports seem to have kept OSM content’s history, at least 
for the samples checked, but many problems were found. In some case, the 
imports brought swimming pools in OSM because they were included in the dataset 
(e.g. Moncton). In other cases, importing buildings with accurate locations 
(XY) over content mapped from less accurate imagery resulted in buildings that 
now overlap the street network (e.g. Squamish). It means that all these 21 
imports 

Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

I think it is desirable to stay close to a KISS (Keep It Simple and Stupid) 
approach for editing data. I have doubts about the need to ensure that a 
building will not be edited twice, or about the advantages of changing the 
angles in the task manager. However, as long as the import process does not 
become tedious or complex, I have no objections.

Daniel

From: Nate Wessel [mailto:bike...@gmail.com]
Sent: Sunday, January 05, 2020 12:30
To: Pierre Béland; talk-ca@openstreetmap.org
Subject: Re: [Talk-ca] Importing buildings in Canada


Yeah, there are issues with the Toronto Simplification tasks ... I was tempted 
to orient the task grid more to the actual streets by rotating everything ~17 
degrees. The problem with that is that when downloading the task data by 
bounding box (i.e. a new unrotated bounding box) you end up getting lots of 
data that's not in the task. I've found that the best way to do the validation 
tasks is to download the task data and then download a slightly expanded 
bounding box to ensure I have everything. Not the cleanest solution, but it's 
the best I've found so far.

Arbitrary task shapes seem to work fine for importing though because you can 
easily see where the new data starts and ends. And buildings can be assigned to 
a task uniquely without difficulty.

Cheers,

Nate Wessel, PhD
Planner, Cartographer, Transport Nerd
NateWessel.com
On 2020-01-05 12:16 p.m., Pierre Béland wrote:
Bonjour Nate,

Cette approche avec taille et forme variable des tâches est intéressante pour 
contrôler le nombre de bâtiments à valider.  Pour éviter les conflits 
d'édition, est-t-il possible de s'assurer qu'un bâtiment se retrouvera dans une 
seule tâche ?

Si des bâtiments se retrouvent sur la ligne de contour de la tâche, il seront 
sélectionnés dans deux tâches différentes. Voir par exemple 
http://tasks.osmcanada.ca/project/168#task/152

Une façon d'éviter cela serait de s'aligner le plus possible sur les routes.


Pierre



Le dimanche 5 janvier 2020 11 h 40 min 49 s UTC−5, Nate Wessel 
 a écrit :



The task size, and even shape is totally customizable. I've set up a couple 
that are entirely based on the density of the data:
http://tasks.osmcanada.ca/project/168
https://tasks.openstreetmap.us/project/107

Best,

Nate Wessel, PhD
Planner, Cartographer, Transport Nerd
NateWessel.com
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Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

Hi James,
That is too bad, but there is no rush at this stage because we are simply 
refining the import procedure. In the meantime, I propose to act as “Task 
manager”. I can provide some tiles (task frame and orthogonalized buildings’ 
footprint) to those who wish to try the import procedure.
I should start importing today with a first tile. If changes/additional 
information are needed to adjust the procedure, I suggest we discuss it on the 
import Talk page [1]

Daniel

[1] 
https://wiki.openstreetmap.org/wiki/Talk:Canada_-_The_Open_Database_of_Buildings


From: James [mailto:james2...@gmail.com]
Sent: Monday, March 09, 2020 20:13
To: Daniel @jfd553
Cc: talk-ca@openstreetmap.org
Subject: Re: [Talk-ca] Importing buildings in Canada

Ok so I have some bad news, the data.osmcanada.ca<http://data.osmcanada.ca> 
server that was being hosted by a friend on AWS was shutdown and wiped. I will 
need to get time to get things setup on another server to host the 
microinstance: https://github.com/osmottawa/micro-data-service
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Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

Hi,
I have adjusted the import procedure to take into account that there will be no 
ODB data server available for a while (James’ email below). I started importing 
data over Squamish using the procedure to test it. It seems OK so far. It would 
be great if others do the same and test the procedure.

Daniel

From: James [mailto:james2...@gmail.com]
Sent: Monday, March 09, 2020 20:13
To: Daniel @jfd553
Cc: talk-ca@openstreetmap.org
Subject: Re: [Talk-ca] Importing buildings in Canada

Ok so I have some bad news, the data.osmcanada.ca<http://data.osmcanada.ca> 
server that was being hosted by a friend on AWS was shutdown and wiped. I will 
need to get time to get things setup on another server to host the 
microinstance: https://github.com/osmottawa/micro-data-service
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Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

The Squamish buildings are not as accurate as expected. It seems that they were 
acquired through automatic image interpretation, with little validation. I 
found many buildings with the roof correctly mapped, but one of the building 
faces (visible on the imagery) was added as a roof component. So there is a lot 
of work to be done. Help is welcome.

Daniel
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Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

Sounds good to me. Can we try it as if I don't have the data? I might then be 
able to clearly document the procedure in the wiki.

Daniel

From: James [mailto:james2...@gmail.com]
Sent: Tuesday, March 10, 2020 10:38
To: Daniel @jfd553
Cc: Talk-CA OpenStreetMap
Subject: Re: [Talk-ca] Importing buildings in Canada

The task is setup in task manager, it was just more convenient serving data via 
the service. I can publish the task and invite those that have enough 
experience (they would need the orthoganalized data though) Which I could 
provide over slack(osm-ca.slack.com<http://osm-ca.slack.com>)

On Tue., Mar. 10, 2020, 10:33 a.m. Daniel @jfd553, 
mailto:jfd...@hotmail.com>> wrote:
Hi James,
That is too bad, but there is no rush at this stage because we are simply 
refining the import procedure. In the meantime, I propose to act as “Task 
manager”. I can provide some tiles (task frame and orthogonalized buildings’ 
footprint) to those who wish to try the import procedure.
I should start importing today with a first tile. If changes/additional 
information are needed to adjust the procedure, I suggest we discuss it on the 
import Talk page [1]

Daniel

[1] 
https://wiki.openstreetmap.org/wiki/Talk:Canada_-_The_Open_Database_of_Buildings


From: James [mailto:james2...@gmail.com<mailto:james2...@gmail.com>]
Sent: Monday, March 09, 2020 20:13
To: Daniel @jfd553
Cc: talk-ca@openstreetmap.org<mailto:talk-ca@openstreetmap.org>
Subject: Re: [Talk-ca] Importing buildings in Canada

Ok so I have some bad news, the data.osmcanada.ca<http://data.osmcanada.ca> 
server that was being hosted by a friend on AWS was shutdown and wiped. I will 
need to get time to get things setup on another server to host the 
microinstance: https://github.com/osmottawa/micro-data-service
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[Talk-ca] Bug with Latest JOSM version

[Daniel @jfd553]

Hi all, here is a warning for those of you that import buildings. The latest 
version of JOSM seems to fail in detecting crossing buildings (which is the 
base of the import process). A ticket has been opened (#19053) to clear the 
problem.

Daniel
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Re: [Talk-ca] Toronto building import

[Daniel @jfd553]

I am about to complete the Squamish test area and so far the new ODB import 
procedure seems adequate. So, if you require the data to be pre-processed over 
the selected area just let me know.
However, I would suggest using squares instead of various polygons to define 
tiles because it is simpler to manage OSM data when downloading it in JOSM.

Best,
Daniel

From: Nate Wessel [mailto:bike...@gmail.com]
Sent: Saturday, April 04, 2020 00:57
To: talk-ca@openstreetmap.org
Subject: [Talk-ca] Toronto building import


Hi all,

I've been spending some time today working on restarting the Toronto building 
import effort which seems to have stalled a while back (I got distracted, 
sorry!).

What I'm proposing to do is essentially just to finish off the building import 
that was started over a year ago in Ontario, though just within the bounds of 
the City of Toronto. That larger import, at the time, never reached the central 
parts of the city and there are about 55,000 buildings that can still easily be 
imported from the ODB.

There is an outline of the proposal here ( 
https://wiki.openstreetmap.org/wiki/Toronto_building_import )

And I've uploaded some task-level OSM data to GitHub ( 
https://github.com/Nate-Wessel/TO-building-import/tree/master/tasks ) if anyone 
cares to inspect it.

Hopefully this import process will address most of the concerns raised about 
the initial import, including those I raised myself ;-)

Anyway, this email is just to notify y'all that I've been working on this again 
and to start the necessary discussions and get any feedback. I'd love to begin 
to move forward in the next couple of weeks if there is support for this effort 
here, and on the imports mailing list. Please let me know what you think!

Best,
--

Nate Wessel, PhD
Planner, Cartographer, Transport Nerd
NateWessel.com
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Re: [Talk-ca] Toronto building import

[Daniel @jfd553]

+1

From: Nate Wessel [mailto:bike...@gmail.com]
Sent: Saturday, April 04, 2020 14:08
To: talk-ca@openstreetmap.org
Subject: Re: [Talk-ca] Toronto building import


Thanks for the offer Daniel! However I've already processed the data through my 
own, similar workflow. I did a building import a couple years ago so I had 
everything set up on my computer already anyway.

I originally tried dividing the tasks into rectangles so that they would better 
match a bounding-box download in JOSM. I didn't like the results so much 
though; if I kept the tasks around the same size (in terms of buildings), the 
size and shape of the tasks varied a bit too much for my comfort, with some 
tasks getting very large ( as in http://tasks.osmcanada.ca/project/168 ).

I found that irregular task shapes didn't cause any trouble for the last import 
I worked on, though they did make validation a bit harder. For better or worse 
though, I've observed that not much task-level validation actually happens in 
projects like this, if all goes well and the data was good in the first place.

Best,

Nate Wessel, PhD
Planner, Cartographer, Transport Nerd
NateWessel.com<https://www.natewessel.com>
On 2020-04-04 9:21 a.m., Daniel @jfd553 wrote:
I am about to complete the Squamish test area and so far the new ODB import 
procedure seems adequate. So, if you require the data to be pre-processed over 
the selected area just let me know.
However, I would suggest using squares instead of various polygons to define 
tiles because it is simpler to manage OSM data when downloading it in JOSM.

Best,
Daniel

From: Nate Wessel [mailto:bike...@gmail.com]
Sent: Saturday, April 04, 2020 00:57
To: talk-ca@openstreetmap.org<mailto:talk-ca@openstreetmap.org>
Subject: [Talk-ca] Toronto building import


Hi all,

I've been spending some time today working on restarting the Toronto building 
import effort which seems to have stalled a while back (I got distracted, 
sorry!).

What I'm proposing to do is essentially just to finish off the building import 
that was started over a year ago in Ontario, though just within the bounds of 
the City of Toronto. That larger import, at the time, never reached the central 
parts of the city and there are about 55,000 buildings that can still easily be 
imported from the ODB.

There is an outline of the proposal here ( 
https://wiki.openstreetmap.org/wiki/Toronto_building_import )

And I've uploaded some task-level OSM data to GitHub ( 
https://github.com/Nate-Wessel/TO-building-import/tree/master/tasks ) if anyone 
cares to inspect it.

Hopefully this import process will address most of the concerns raised about 
the initial import, including those I raised myself ;-)

Anyway, this email is just to notify y'all that I've been working on this again 
and to start the necessary discussions and get any feedback. I'd love to begin 
to move forward in the next couple of weeks if there is support for this effort 
here, and on the imports mailing list. Please let me know what you think!

Best,
--

Nate Wessel, PhD
Planner, Cartographer, Transport Nerd
NateWessel.com<https://www.natewessel.com>
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Re: [Talk-ca] Iles de Boucherville

[Daniel @jfd553]

+1

Sent from Galaxy S7


From: Pierre Béland via Talk-ca 
Sent: Wednesday, April 1, 2020 8:53:00 AM
To: Talk-CA OpenStreetMap ; Martin Chalifoux 

Subject: Re: [Talk-ca] Iles de Boucherville

Bonnes nouvelles.  Pour ce qui est du circuit canot,  j'ai créé une relation 
route=canoe. Il en existe déjà 549.  J'ai indiqué rôles forward / backward. À 
voir si cela est correct pour indiquer le sens du parcours.

voir https://www.openstreetmap.org/relation/10947406

Pierre


Le mercredi 1 avril 2020 06 h 27 min 59 s UTC−4, Martin Chalifoux 
 a écrit :


Victoire on dirait. Bonne chose de réglée. Merci.
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Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

Hi all,
I just completed the task #173 (Squamish - Building Import) benchmark. The 
import procedure seems OK. So I think anyone interested in completing the 
import for other areas is welcome, as long as the procedure is respected.

Regarding the Squamish area, the presence of numerous GPS tracks really made a 
difference. ODB buildings were (too) often badly positioned and not to scale, 
something I could not have seen or confirmed without these tracks. I then 
encourage everyone to upload their GPS tracks in OSM! The Import Status for 
Squamish has been updated to “Completed” [1].

Regarding task #175 - Toronto Building Import, I understand that Nate Wessel is 
going to the complete the job alone? I updated the Import Status for Toronto 
but Nates’ import account is not identified yet [2].

A lot of tasks are still waiting for us so good mapping!
Daniel

[1] 
https://wiki.openstreetmap.org/wiki/Canada_-_The_Open_Database_of_Buildings#British_Columbia
[2] 
https://wiki.openstreetmap.org/wiki/Canada_-_The_Open_Database_of_Buildings#Ontario

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Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

Well, looking at the Squamish import, I just found out that I imported 
everything using my standard account, not my import account :-(
The problem is that many years ago I configured JOSM to use OAuth-based 
authentication and did not change it. I thought that the task manager was going 
to use my import account to interact with JOSM's remote control (because I used 
my import account to log into the task manager), which does not seem to be the 
case.
It is therefore important to ensure that the account used is the correct one. I 
modified the import procedure to ask users to check the account used in JOSM 
prior to import data. I will use basic authentication for better control during 
the next import. If it were possible to change the data contributor a 
posteriori I would do so, but I don't think it is possible. That is bad.

Daniel

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Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

Hi,
I completed more than a dozen tiles of the task #173 (Squamish). That would be 
interesting if some of you could validate what I did so far, in order to adjust 
the procedure if required.
Thanks.

Daniel

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Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

Thank,
I'll have a look at that tomorrow. I'll get back to you for further comments an 
changes to the procedure if required.
Daniel

Sent from Galaxy S7


From: Tim Elrick 
Sent: Saturday, March 21, 2020 6:23:59 PM
To: talk-ca@openstreetmap.org 
Subject: Re: [Talk-ca] Importing buildings in Canada

Hi Daniel,

I had a brief look at project #173, task #20 and found that you can
either align the hospital with the underlying imagery or the houses to
the right of the task, but not both at the same time (Bing and ESRI bear
the same effect). This might have to do with different
projections/coordinate reference systems used by the data provider of
the buildings and the one used by the aerial imagery provider.
If we assume that the aerial imagery data is the correctly projected (as
we do as default in OSM, at least for Bing imagery), we would have to
correct the position of all the buildings according to the underlying
aerial imagery.

Furthermore, the buildings to be imported seem to have an odd level of
detail. Some are pretty detailed, some are missing details at all. I did
not only look at task #20 which you have already worked on, but also
task #21. Not sure if they were automatically collected or if a bored
intern had to do this - that would explain the varying quality.

Apart from the location of the buildings, you did a great job, I think.

Unfortunately, I am still working on two other projects in the tasking
manager at the moment, so, I most probably won't be of much help on
#173, but who knows, we are all grounded at the moment, aren't we?

Happy mapping,
Tim


On 2020-03-20 10:23, Daniel @jfd553 wrote:
Hi,

I completed more than a dozen tiles of the task #173 (Squamish). That
would be interesting if some of you could validate what I did so far, in
order to adjust the procedure if required.

Thanks.

Daniel


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Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

Hi all, sorry for this long Email.

Thanks to Tim to have comment! He wrote: “I [...] found that you can either 
align the hospital with the underlying imagery or the houses to the right of 
the task, but not both at the same time. [...]  If we assume that the aerial 
imagery data is the correctly projected [...], we would have to correct the 
position of all the buildings according to the underlying aerial imagery.”

Well, you are right. Actually, I did not align most of the buildings to the 
image! Why? Because unless proven otherwise, ODB data should be more accurate 
(XY) than most images available, especially in hilly areas. 
Municipalities generally use aerial photos to create their maps (ODB data). 
Because these aerial photos provide multiple views of the same area, they can 
be used to compute digital elevation models (DEMs) showing even buildings’ 
height. Only once done, they can create accurate ortho-images (orthographic 
view [1]). Without an accurate DEM, objects location on an image is not 
accurate either, because we are in a perspective view [1]. 
The DEMs used to create available OSM images generally do not have a sufficient 
accuracy in mountainous areas. This is the case of the Squamish area where the 
image shows many examples of perspective views [1]. In flat areas, this effect 
is minimal, which makes it possible to adjust an image over a large region with 
a great accuracy. The only visible effect is then related to buildings’ height. 

Regarding the hospital, it is located on a hill between two plateaus. The image 
can be adjusted with a good accuracy on the flat area near the river, or on the 
plateau on the top of the hill (potentially with another offset), but it is 
more difficult in between. I tried to adjust its geometry (details) from its 
original ODB location. 

I adjust the image to surrounding buildings when I need to map a new one or add 
details to an existing one. I may also look at available GPS tracks to confirm 
general ODB data location.

Thanks again. Comments?
Daniel

[1] https://en.wikipedia.org/wiki/Orthophoto
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Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

Lol

Sent from Galaxy S7


From: Tim Elrick 
Sent: Sunday, March 22, 2020 6:49:48 PM
To: Daniel @jfd553 
Cc: talk-ca@openstreetmap.org 
Subject: Re: [Talk-ca] Importing buildings in Canada

Hi Daniel,

I agree with you. I didn't pay attention to the fact that Squamish is
located in a hilly area.

Greetings from Quebec's flatlands,
Tim

On 2020-03-22 14:16, Daniel @jfd553 wrote:
Hi all, sorry for this long Email.

Thanks to Tim to have comment! He wrote: “I [...] found that you can
either align the hospital with the underlying imagery or the houses to
the right of the task, but not both at the same time. [...]  If we
assume that the aerial imagery data is the correctly projected [...], we
would have to correct the position of all the buildings according to the
underlying aerial imagery.”

Well, you are right. Actually, I did not align most of the buildings to
the image! Why? Because unless proven otherwise, ODB data should be more
accurate (XY) than most images available, especially in hilly areas.
Municipalities generally use aerial photos to create their maps (ODB
data). Because these aerial photos provide multiple views of the same
area, they can be used to compute digital elevation models (DEMs)
showing even buildings’ height. Only once done, they can create accurate
ortho-images (orthographic view [1]). Without an accurate DEM, objects
location on an image is not accurate either, because we are in a
perspective view [1].
The DEMs used to create available OSM images generally do not have a
sufficient accuracy in mountainous areas. This is the case of the
Squamish area where the image shows many examples of perspective views
[1]. In flat areas, this effect is minimal, which makes it possible to
adjust an image over a large region with a great accuracy. The only
visible effect is then related to buildings’ height.

Regarding the hospital, it is located on a hill between two plateaus.
The image can be adjusted with a good accuracy on the flat area near the
river, or on the plateau on the top of the hill (potentially with
another offset), but it is more difficult in between. I tried to adjust
its geometry (details) from its original ODB location.

I adjust the image to surrounding buildings when I need to map a new one
or add details to an existing one. I may also look at available GPS
tracks to confirm general ODB data location.

Thanks again. Comments?
Daniel

[1] https://en.wikipedia.org/wiki/Orthophoto

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Re: [Talk-ca] Importing buildings in Canada

[Daniel @jfd553]

Cool, thanks!

Sent from Galaxy S7


From: James 
Sent: Tuesday, March 10, 2020 1:56:16 PM
To: Daniel @jfd553 
Cc: Talk-CA OpenStreetMap 
Subject: Re: [Talk-ca] Importing buildings in Canada

Project #173. I've set you as an experienced mapper and you should be able to 
see it.

http://tasks.osmcanada.ca/project/173

On Tue., Mar. 10, 2020, 1:05 p.m. Daniel @jfd553, 
mailto:jfd...@hotmail.com>> wrote:

Sounds good to me. Can we try it as if I don't have the data? I might then be 
able to clearly document the procedure in the wiki.



Daniel



From: James [mailto:james2...@gmail.com<mailto:james2...@gmail.com>]
Sent: Tuesday, March 10, 2020 10:38
To: Daniel @jfd553
Cc: Talk-CA OpenStreetMap
Subject: Re: [Talk-ca] Importing buildings in Canada



The task is setup in task manager, it was just more convenient serving data via 
the service. I can publish the task and invite those that have enough 
experience (they would need the orthoganalized data though) Which I could 
provide over slack(osm-ca.slack.com<http://osm-ca.slack.com>)



On Tue., Mar. 10, 2020, 10:33 a.m. Daniel @jfd553, 
mailto:jfd...@hotmail.com>> wrote:

Hi James,

That is too bad, but there is no rush at this stage because we are simply 
refining the import procedure. In the meantime, I propose to act as “Task 
manager”. I can provide some tiles (task frame and orthogonalized buildings’ 
footprint) to those who wish to try the import procedure.

I should start importing today with a first tile. If changes/additional 
information are needed to adjust the procedure, I suggest we discuss it on the 
import Talk page [1]



Daniel



[1] 
https://wiki.openstreetmap.org/wiki/Talk:Canada_-_The_Open_Database_of_Buildings





From: James [mailto:james2...@gmail.com<mailto:james2...@gmail.com>]
Sent: Monday, March 09, 2020 20:13
To: Daniel @jfd553
Cc: talk-ca@openstreetmap.org<mailto:talk-ca@openstreetmap.org>
Subject: Re: [Talk-ca] Importing buildings in Canada



Ok so I have some bad news, the data.osmcanada.ca<http://data.osmcanada.ca> 
server that was being hosted by a friend on AWS was shutdown and wiped. I will 
need to get time to get things setup on another server to host the 
microinstance: https://github.com/osmottawa/micro-data-service
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Re: [Talk-ca] York Region Building Import

[Daniel @jfd553]

Hi all.
The York Region is a component of ODB data import, which has been widely 
discussed and we all agreed that whole import process was acceptable. There is 
then no reason to go back to the import mailing list to do the discussion 
again. Look here [1] for the appropriate import procedure.

Speaking of buildings... In order to stay active during Covid-19 lockdowns, I 
have been working on a Covid-19 personal mapping project since mid-April. My 
objective was to map the buildings in Sherbrooke (ODB only providing 5% of the 
buildings).
After mapping around 30,000 buildings (according to an Overpass Turbo query), 
80% of my initial goal is achieved. I keep moving forward with mapping and 
updating buildings and related features.

Best regards

[1] https://wiki.openstreetmap.org/wiki/Canada_-_The_Open_Database_of_Buildings

From: john whelan [mailto:jwhelan0...@gmail.com]
Sent: Monday, October 05, 2020 22:55
To: Andrew Deng
Cc: Talk-CA OpenStreetMap
Subject: Re: [Talk-ca] York Region Building Import

There are two sources of buildings to import one is Bing the other is the stat 
Canada licensed one.  Both have the correct license for OSM.

If you are going after the stat can one then there was an import plan drawn up 
for Canada and that is in the wiki.

I suggest if you use the stat can import plan basically just copy it together 
with the license information or perhaps you can do a sort of amendment of it to 
cover York.  The reason I suggest that is there is an import mailing group that 
gets involved and they tend to ask all sorts of questions.  Getting by them has 
been described as the hardest part of the import process.

The original import was done in Ottawa and we got all the licensing permissions 
sorted out and because Ottawa is fairly small the local group formed a 
consensus that that is what they were happy with and that was the basis of that 
import.

When we set it up to import across Canada the problem with the stat can data 
was the quality varied from municipality to municipality and there was some 
concerns about if the data should be preprocessed in some way.  Also in some 
areas such as Toronto local mappers wanted to feel more in control.

I can't recall who came up with the preprocessing but I'm sure James will 
remember.  Pierre I'm almost certain expressed his opinion.  It might be worth 
looking at what they came up with and why.  I do recall that some mappers 
thought the Ottawa building import should have been preprocessed but the local 
mappers were happy with the raw data.

Cheerio John

On Sun, Oct 4, 2020, 12:32 PM Andrew Deng via Talk-ca 
mailto:talk-ca@openstreetmap.org>> wrote:
Hello,

I primarily map in York Region, Ontario, and I have noticed that the Toronto 
Building Import has been completed 3 months ago. Therefore, I am proposing to 
open a task on the Task Manager for York Region buildings, since having the 
buildings imported here would be nice. I'm not sure of the process on how to do 
that, which is why I'm emailing this group.


--



Andrew (andrepoiy on OSM)

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Re: [Talk-ca] York Region Building Import

[Daniel @jfd553]

There is a list of available datasets and the proportion of existing/imported 
buildings for each municipality [1].

Daniel

[1] https://wiki.openstreetmap.org/wiki/Canada_-_The_Open_Database_of_Buildings


From: John Whelan [mailto:jwhelan0...@gmail.com]
Sent: Tuesday, October 06, 2020 09:25
To: Daniel @jfd553
Cc: Andrew Deng; Talk-CA OpenStreetMap
Subject: Re: [Talk-ca] York Region Building Import

Apologies for omitting your name.  I hang my head in shame.

So the final result on the building import was the process and licenses are 
fine but local mappers need to agree with the import being done and if they do 
they can just go ahead but should follow the agreed process?

How many areas does the data exist for that haven't been imported yet? Perhaps 
there might be some interest in importing a few other areas.

Thanks John

Daniel @jfd553 wrote on 2020-10-06 00:00:

Hi all.
The York Region is a component of ODB data import, which has been widely 
discussed and we all agreed that whole import process was acceptable. There is 
then no reason to go back to the import mailing list to do the discussion 
again. Look here [1] for the appropriate import procedure.

Speaking of buildings... In order to stay active during Covid-19 lockdowns, I 
have been working on a Covid-19 personal mapping project since mid-April. My 
objective was to map the buildings in Sherbrooke (ODB only providing 5% of the 
buildings).
After mapping around 30,000 buildings (according to an Overpass Turbo query), 
80% of my initial goal is achieved. I keep moving forward with mapping and 
updating buildings and related features.

Best regards

[1] https://wiki.openstreetmap.org/wiki/Canada_-_The_Open_Database_of_Buildings

From: john whelan [mailto:jwhelan0...@gmail.com]
Sent: Monday, October 05, 2020 22:55
To: Andrew Deng
Cc: Talk-CA OpenStreetMap
Subject: Re: [Talk-ca] York Region Building Import

There are two sources of buildings to import one is Bing the other is the stat 
Canada licensed one.  Both have the correct license for OSM.

If you are going after the stat can one then there was an import plan drawn up 
for Canada and that is in the wiki.

I suggest if you use the stat can import plan basically just copy it together 
with the license information or perhaps you can do a sort of amendment of it to 
cover York.  The reason I suggest that is there is an import mailing group that 
gets involved and they tend to ask all sorts of questions.  Getting by them has 
been described as the hardest part of the import process.

The original import was done in Ottawa and we got all the licensing permissions 
sorted out and because Ottawa is fairly small the local group formed a 
consensus that that is what they were happy with and that was the basis of that 
import.

When we set it up to import across Canada the problem with the stat can data 
was the quality varied from municipality to municipality and there was some 
concerns about if the data should be preprocessed in some way.  Also in some 
areas such as Toronto local mappers wanted to feel more in control.

I can't recall who came up with the preprocessing but I'm sure James will 
remember.  Pierre I'm almost certain expressed his opinion.  It might be worth 
looking at what they came up with and why.  I do recall that some mappers 
thought the Ottawa building import should have been preprocessed but the local 
mappers were happy with the raw data.

Cheerio John

On Sun, Oct 4, 2020, 12:32 PM Andrew Deng via Talk-ca 
mailto:talk-ca@openstreetmap.org>> wrote:
Hello,

I primarily map in York Region, Ontario, and I have noticed that the Toronto 
Building Import has been completed 3 months ago. Therefore, I am proposing to 
open a task on the Task Manager for York Region buildings, since having the 
buildings imported here would be nice. I'm not sure of the process on how to do 
that, which is why I'm emailing this group.


--



Andrew (andrepoiy on OSM)

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--
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Re: [Talk-ca] NRCan lakes

[Daniel @jfd553]

OMG, a lot of pertinent questions!
You are summarizing questions than were discussed on this list over the last 
decade. Discussions about canvec/osm data modeling, internal canvec data 
sources, import problems, edits problems, and artifacts from osm validation 
tools' history!
Because of that, you cannot assume any coast-to-coast consistency with the 
problems you have identified, although you can find them almost everywhere.
Here are some clues. Canvec model did not change much over years but the 
sources used to build the product changed (from federal to 
provincial/municipal). As far as I know,  canvec.osm product is not maintained 
anymore, even if its last version is still available. When you find 
inconsistencies, look at data history. It may help to identify if a problem 
comes from an initial import, from an adjustment with existing data, from a 
duplicated erroneous import, or from subsequent edits.
Good mapping!
Daniel

Sent from Galaxy S7


From: Hannes Röst 
Sent: Wednesday, July 8, 2020 11:41:50 AM
To: pierz...@yahoo.fr 
Cc: Talk-CA OpenStreetMap 
Subject: Re: [Talk-ca] NRCan lakes


Dear Pierre

Thanks a lot, your explanation of the history is very helpful.  I can also see 
on the wiki and the mailing list some threads and pages that explain the import 
but some of the wiki pages are quite old (10 years or so) and its not clear 
whether they still all apply and contain current policy.

In your example it seems that the import produced duplicated ways sometimes 
where the lake and the multipolygone (inner) were identical.In this case I see 
that they can be found with the JOSM validator 
(org.openstreetmap.josm.data.validation.tests.DuplicateWays and can then be 
merged (Shift-J) but its 4 clicks for each merge so quite some work and a 
script could potentially fix that automatically.


When I look more closely, however, I think this is partially an import artefact 
and partially a problem in the input data. Take for example the case of 
https://www.openstreetmap.org/way/129592036 and 
https://www.openstreetmap.org/way/129592039 which has the same issue (one 
tagged as "inner" and one as water) and I look in the current CanVec data 
031L03 0.3.3 then I only see a single way with 14 nodes at that position. In 
the same tile I find the ways https://www.openstreetmap.org/way/129592307 and 
https://www.openstreetmap.org/way/129592315 are duplicated both in OSM as well 
as in the input CanVec data tile 031L03 0.3.3 (one is inner of wetland, the 
other inner of wood). I am not sure where this error comes from but it clearly 
highlights the need for manual fixup of the imported data.

> Ici on peut  par exemple ne conserver que le lac (way/60852636) et effacer le 
> doublon pour le role inner (way/60854569) et réviser la relation 
> multipolygone pour y indiquer way/60852636 avec role=inner.

Yes I think that is possible with JOSM by selecting both and hitting Shift-J 
and then making sure to click "Keep" in the relation. But its a lot of work 
because it is currently done manually and it seems this could easily be done by 
a script (this was already discussed several years back, especially doing this 
automatically but nothing seems to have happened [1]).

Another issue that I found in the import is with highways: the "almost 
connected but not connected" ways, luckily they can be found by Osmose but 
create a ton of warnings: 
http://osmose.openstreetmap.fr/en/map/#zoom=12=46.0489=-77.5019==1==

What I also dont understand is differences between CanVec imports, for example 
looking at the same tile as above ( 031L03 0.3.3 ) there are several waterways 
that are missing in the CanVec data, for example 
https://www.openstreetmap.org/way/129591734 (tagged with NRCan-CanVec-8.0) is 
not present any more in the tiles that I downloaded from [2] - is there some 
error here, was the stream removed on purpose in the newer CanVec data? In the 
ESRI and Bing satellite data I can clearly see a feature there in the woods 
that looks very much like a waterway, so it looks like some sort of stream is 
there, but not in other images from Maxar (maybe its only part of the year?). 
So why is it missing in newer CanVec data? How should we deal with these cases 
in OSM ?

Best

Hannes

1. https://lists.openstreetmap.org/pipermail/talk-ca/2016-September/007225.html
2. https://ftp.maps.canada.ca/pub/nrcan_rncan/vector/osm/


Gesendet: Dienstag, 07. Juli 2020 um 12:18 Uhr
Von: "Pierre Béland" 
An: "Talk-CA OpenStreetMap" 
Cc: "Hannes Röst" 
Betreff: Re: [Talk-ca] NRCan lakes

Petit rappel pour ceux moins familiers avec les imports Canvec. Il est bon de 
bien connaître la structure des données et doublons éventuels à corriger. Aussi 
JOSM est très utile pour repérer les chemins en doublon et corriger.

Les développeurs OSM mentionnent régulièrement des multipolygones bois (imports 
Canvec) très grands et complexes qui causent des problèmes de traitement de 
données dans la base de 

Re: [Talk-ca] NRCan lakes

[Daniel @jfd553]

Have a look at the osm wiki page for canvec import, you will understand why.

Sent from Galaxy S7


From: Hannes Röst 
Sent: Tuesday, July 7, 2020 1:02:43 AM
To: talk-ca@openstreetmap.org 
Subject: [Talk-ca] NRCan lakes

Hello

I am a contributor from Toronto and I have a question regarding how to
treat some of the CanVec 6.0 - NRCan imports, specifically for lakes.
I came across this lake here:

https://www.openstreetmap.org/way/69275451
https://www.openstreetmap.org/way/69277932
https://www.openstreetmap.org/way/69745752

Which is strangely split up into 3 parts and I wonder how to proceed:
should we fix this and create a single way out of these 3 parts or is
it beneficial (for comparison to future NRCan database entries) to
keep them that way and create a relation out of the three? Also, does
somebody know why the NRCan dataset does this, is this an import
artefact (splitting into tiles?) and should be corrected when encountered
or is it part of the original dataset?

Best

Hannes Rost

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