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Mapping missing roads in cities of Malaysia, Indonesia and Vietnam #32

Closed GRABOSM closed 4 years ago

GRABOSM commented 5 years ago

Objective: Grab team has mapped these regions in the past and this time we are going through the existing road geometries and add the missing ones if any. We'll be reviewing and mapping the following features: missing roads, road classification, and check for intersection configurations and alignment accuracy.

800px-NorthSouth-Expressway _Source: By mailerdiablo - Self-taken (Touched Up), CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=553058

Regions we are reviewing/mapping:

Regions we are reviewing/mapping:

Workflow: We'll be following the same workflow as mentioned in our wiki - https://github.com/GRABOSM/Grab-Data/blob/master/Data%20Improvement%20Projects and https://wiki.openstreetmap.org/wiki/Grab#Process_Flow

Validation: We'll be following the validation guidelines mentioned in our wiki: https://wiki.openstreetmap.org/wiki/Grab#Quality_Process

Changeset Comment: Mapping missing roads and road attributes https://github.com/GRABOSM/Grab-Data/issues/32

Source: Digital Globe Premium -- we would refer to others if need be.

Filter: None

Plugins: None

Edge cases: None at the moment, we'll post it as a subsequent comment if need be.

Team involved: The Grab Data team

Do reach out to us if you have any questions or suggestions on the same. Happy Mapping!

cc: @jinalfoflia

MASangys commented 5 years ago

Hope that Grab team can add Seremban in this list too because I noticed area within Seremban District lack of road data compare to other cities too.

GRABOSM commented 5 years ago

@MASangys thank you for the suggestion, have noted this. We'll soon be updating the list with a few more cities where the team will be mapping.

GRABOSM commented 5 years ago

We have updated the original list with a few more cities. Here are the new ones:

If there are any questions, suggestions or recommendations related to these regions, please do let us know.

AkuAnakTimur commented 5 years ago

In the state of Kedah, Malaysia; while I'm trying my best to respond to changeset discussion left by the team; I reckon a serious issue was discovered.

Outside urban areas, usually there would be a huge area of paddy fields. Sure, it would indicate areas that would be likely unmapped. Example, this place (aerial imagery available to be exploited for OpenStreetMap) which is about 30km away from the state capital, Alor Setar.

Typical highways around this area includes highway=unclassified, highway=residential, highway=service as feeder roads to one of two houses built around the area, and probably highway=track that potentially make up most (unmapped) highways in this said area.

highway=track may pose a challenging task to be mapped. It may be erroneously mapped as a highway with a higher classification or hierarchy. I've spotted this error from the mapping team, and left some discussion on a changeset as well.

These are usually can be found randomly next to canals, slithering around the paddy fields. It may be paved with rough gravels or simply just bare ground.

Hopefully these issue will be rectified by the team, because apparently I can see a lot of major highways were mapped and they started to appear quite densely on the OpenStreetMap.org website too.

P.S. I'll try my best to respond to discussion left by the team, one by one.

GRABOSM commented 5 years ago

Hello @AkuAnakTimur, thank you for bringing it to our attention. We mapped these roads based on the historical data, that is, previously the local mappers have added these to be unclassified roads and we did not want to abruptly change the classification.

Also, the OSM policy for an unclassified road in rural areas states this:

"In some countries, unclassified roads may be unpaved in larger, poorer or more remote/rural areas, and are typically paved in denser, richer or more central/urban areas. In this case, you should add a surface=* tag to indicate the surface.

Can you help us better understand why were they mapped/tagged as unclassified routes previously? As well as the reason they were considered as tracks now. Since one of the roads connect to major roads, we'd want to retain the connecting roads to be unclassified itself.

Thanks again for the feedback and our team really appreciate your responses and help as they are helping us better our approach.

AkuAnakTimur commented 5 years ago

Hello, thank you for the reply.

Can you help us better understand why were they mapped/tagged as unclassified routes previously? As well as the reason they were considered as tracks now. Since one of the roads connect to major roads, we'd want to retain the connecting roads to be unclassified itself.

It's undeniable that some highways across rice fields can be mapped as highway=unclassified. It's very likely that I have chosen the route with a better surface to go through (paved with asphalt) on my humble moped, surveying for OpenStreetMap as a hobby. Hence, the team may have stumbled across some highways mapped as major or significant highways (highway=unclassified and to some extent highway=residential).

image Image source

Puzzles may appear at some certain places: some streets or paths across these agricultural landuses may not be highway=unclassified or even highway=residential.

image Image source, with coordinates

It may appear from imageries that these highways: ways 706559610 and 708427243 ; (in OpenStreetMap terminology) appear suitable for motor vehicles. However, from ground truth (see above picture), it's not the case. It may serve as a driveway (highway=service + service=driveway) to the only house around this very small area.

Those two highways were changed back into major highways after I responded to one of your team's edit.

The two highways - ways 708700387 and 708700386 - just opposite to those first two, were mapped incorrectly. Good news, corrections were applied after I've left a discussion on one of the many changesets.

From ground truth, here's what actually the latter two look like:

Image source, with coordinates

In a nutshell: these situations show how tricky it could be to map across the paddy fields in the state of Kedah, Malaysia. I have provided some examples where the team actually would really have to seek opinion from at least a local mapper: everyone wants minimal inaccurate data in OpenStreetMap.

There may be more mistagged highways across the area of the team's editing interest, but I will be happy to let the team know sooner or later.

From the forum, if the team is somewhat rushing for a deadline, the highway=road tag is simply perfect. The team may return later to further scrutinize the data, tagging things more appropriately.

If these tricky ways need to be classified, by hook or by crook, in reality there's no shortcut for that. I might be very wrong too. Look for hints in the imagery, especially the density of any nearby dwellings. Lower the classification of any ways if it reckoned not to be very important in terms of traffic.

I will comment more on other related issues - allow me some more time.

GRABOSM commented 5 years ago

@AkuAnakTimur thank you so much for the detailed explanation. The team will make the changes as per your suggestions and update the data accordingly.

MASangys commented 4 years ago

Hello @AkuAnakTimur, thank you for bringing it to our attention. We mapped these roads based on the historical data, that is, previously the local mappers have added these to be unclassified roads and we did not want to abruptly change the classification.

Also, the OSM policy for an unclassified road in rural areas states this:

"In some countries, unclassified roads may be unpaved in larger, poorer or more remote/rural areas, and are typically paved in denser, richer or more central/urban areas. In this case, you should add a surface=* tag to indicate the surface.

Can you help us better understand why were they mapped/tagged as unclassified routes previously? As well as the reason they were considered as tracks now. Since one of the roads connect to major roads, we'd want to retain the connecting roads to be unclassified itself.

Thanks again for the feedback and our team really appreciate your responses and help as they are helping us better our approach.

Hello, any update for now? Is Grab Team still improving Malaysian's road geometries?

GRABOSM commented 4 years ago

@MASangys we are still improving some of the cities, here's the current status of the cities we have completed and are currently working on:

Country City Status No. of Kms of roads added
Malaysia (MY) Sandakan completed 1134.4
MY Alor Setar completed 3991.4
MY Sibu completed 1533.4
MY Langkawi completed 260.6
MY Tawau WIP
MY Kuantan WIP
Indonesia (ID) Bengkulu completed 404.7
ID Bandung completed 17444.7
ID Yogyakarta WIP
ID Makassar WIP
ID Bali WIP
Vietnam (VN) Khanh Hoa YTS
VN Ho Chi Minh YTS

WIP -> Work in Progress; YTS -> Yet to start

We'll post an update for everyone as soon as we have completed a few more cities.

cc: @jinalfoflia

GRABOSM commented 4 years ago

Status update

Region City Status Total Kms of roads added
Malaysia Sandakan Completed 1199
Malaysia Tawau WIP    
Malaysia Kuantan YTS    
Malaysia Alor Setar Completed 4012
Malaysia Sibu Completed 1534
Malaysia Langkawi Completed 260
Indonesia Yogyakarta WIP    
Indonesia Kendari WIP      
Indonesia Bengkulu Completed 362
Indonesia Makasar WIP      
Indonesia Bandung Completed 17444
Indonesia Bali WIP      
Vietnam Khanh Hoa YTS      
Vietnam Ho Chi Minh YTS      

WIP -> Work in Progress; YTS -> Yet to start

We have updated the list of other cities that we are adding in the original post.

GRABOSM commented 4 years ago

Closing this issue and opening separate individual cities for each country, thank you everyone for the help and suggestions. Looking forward to mapping together.

AkuAnakTimur commented 4 years ago

Hello! Your team is back, right now mapping around the state of Perlis, Malaysia. The changeset comment left by your team, apparently still pointed over here.

I wonder to whom your team of mappers leave OSM Notes for. Is it for internal use, or those OSM Notes are left for the other mappers?

GRABOSM commented 4 years ago

@AkuAnakTimur apologies, we recently closed this ticket and opening a dedicated one for Malaysian cities. Thus the reason why it's still pointing here.

I wonder to whom your team of mappers leave OSM Notes for. Is it for internal use, or those OSM Notes are left for the other mappers?

We drop notes so that we can seek help from local mappers to get a better understanding of the on-the-ground situation. These aren't for internal use, as a practice, the team tries to reach out to the mappers through changeset comments or via notes, in-case there's a need for clarification. Thanks so much for helping us. Happy Mapping.

AkuAnakTimur commented 4 years ago

@AkuAnakTimur apologies, we recently closed this ticket and opening a dedicated one for Malaysian cities. Thus the reason why it's still pointing here.

We drop notes so that we can seek help from local mappers to get a better understanding of the on-the-ground situation. These aren't for internal use, as a practice, the team tries to reach out to the mappers through changeset comments or via notes, in-case there's a need for clarification. Thanks so much for helping us. Happy Mapping.

Thanks for replying.

Let me point a more convenient place to leave these notes:

image

Select any particular highway first, and then leave annotations as appropriate.

image