OpenStreetMap

Uyan's Diary

Recent diary entries

Using Layer Opacity to Validate (ft. JOSM)

Posted by Uyan on 23 February 2020 in English.

A quick but useful tip I found hidden in this video:

https://www.youtube.com/watch?v=iwJnZQFi_C8

At around 24:00, the speaker notes the use of opacity: using multiple layers, and lowering the opacity of the front/uppermost layer to verify map alterations across different data sets (“data sets” being the layers themselves i.e. Bing, Esri, Maxar etc.). A tip I’ve already had good success with. I find lowering the opacity to around 70% works nicely.

What Imagery to Use for Validation?

Posted by Uyan on 21 February 2020 in English.

After I validate a square in HOTOSM Tasking Manager, I label what imagery I validated the square against (e.g. Bing, Esri, Maxar). I got this idea after seeing mappers comment with which imagery they mapped their buildings, roads etc.

The problem arises when the imagery is validated against a different imagery that was used to map the area. For example, I regularly validate against Bing Aerial Imagery, but sometimes users have noted that they used Maxar Premium Imagery. It would make sense for me to instead validate using the same imagery - in this case Maxar - but when loading the imagery in JOSM I get the following message:

Error downloading tiles: INVALID CONNECT ID: apiKey

There are also other problems. Bing has the highest resolution imagery, the main reason it is my preferred imagery to validate against. Esri has lower resolution, and is also inconsistent with Bing, in large part due to them having taken the pictures at different times/dates in history. Which poses another question: which imagery is the most up-to-date? I’ve assumed Bing, but that assumption is without reason.

Unnamed Highways

Posted by Uyan on 21 January 2020 in English.

Something I’ve come across numerous times during the validation process have been unnamed highways. Given how little experience I have mapping roads, I must say that I don’t know what the problem is. These highways are always tagged, but I’m guessing they’re missing their official name e.g. Blue Ridge Parkway.

I wouldn’t know where to get these names except from other mapping services, since if I understand correctly we should not use them as it is not first-hand data (open-source aiming to “build from from the ground up”). And I feel like I’m at the point where I can no longer simply brush off all these warnings, which might indicate that I need to step away from the validation process to take a crash course in road mapping. Perhaps it is that which will lead me down the road to riches.

Saving Time While Mapping - Part 2

Posted by Uyan on 8 January 2020 in English.

Whilst doing my current routine of validating mapped areas, I came across what is potentially a significant time save. The mapper(s) had drawn an area around a large group of houses and labelled it as a “residential area”, instead of what I and I imagine many others currently do of mapping individual buildings.

This seems like a humongous time save in areas where the details of buildings (e.g. their name) are unknown. But I do have a feeling that ultimately one would want to map each building, as it would be helpful to know where the nearest hospital is, for example, rather than having to scour the area in an emergency.

A compromise could be to map unknown areas with these all-encompassing residential area squares, whilst filling in individual details for known buildings. I know that busy areas such as London and New York are already mapped out in great detail, so I can only assume that the time save I am proposing would just be the first step in mapping an area. If the idea is acceptable, I would then assume the idea would be used in the initial mapping stage, and that validators would fill in the details. That is, unless there is another step after the validation stage that I am unaware of (I am currently only an intermediate mapper and cannot validate all maps). I could also see the details being filled in during further iterations of the mapping process, such as when extra data on an area is gathered.

Missing Maps and HOTOSM Synchronicity

Posted by Uyan on 17 December 2019 in English.

Having originally found OSM through the collaborative project called Missing Maps, tasks that I complete are recorded on my HOT Tasking Manager (HOTOSM) profile. OSM accounts are also linked to Missing Maps profiles, where badges and achievements like those found in video games can be obtained.

Over the past few days I’ve noticed that the sync between OSM and these 2 other platforms, HOTOSM and Missing Maps, has not been completely up to date. For example, in HOTOSM there is a “number of changes/edits to go until you become an advanced mapper” bar that fills as you make edits in OSM. This bar has been filling up as expected, but the “total mapping time” hasn’t changed. I’ve barely obtained any Missing Maps badges either, whose objectives I have already surpassed. Neither of these features mean a great deal - as long as the mapping gets done then that’s the main focus. But it would be nice to know what the problem with the synchronization is and if it can be fixed.

Improving My Validation Skills

Posted by Uyan on 10 December 2019 in English.

For the past week or so I have started validating squares in OpenStreetMap. Unless I am doing something wrong, the task feels just the same as when I was mapping squares. The main thing I have noticed is that there is still inconsistencies in the drawing of buildings and roads. For example, each of the corners of some buildings are all slightly off, culminating in a building that despite being in the same location as the building in the GPS imagery, is pretty far off from being mapped precisely.

I don’t know how much of an issue this is, but I do know that if I didn’t work on ironing out these creases in the mapping, then I’d barely be doing any work on the software! It might be a case similar to the woodland mapping in one of my previous diary entries, where it’s largely a waste of time to map so much area that contains very little, if any, inhabitants. Or it might be a case of me being slightly perfectionist/pedantic in my mapping. I do take some pride in my attention to detail, which I know is very important in the world of CAD, construction etc., I’m just not sure if that detail is also a value commodity in the mapping industry

JOSM - My Initial Thoughts

Posted by Uyan on 5 November 2019 in English.

I started learning how to use JOSM today, and I quickly noticed some advantages over the online iD editor. The first would be the seamless editing. Since there’s no need to “stream” data, all the actions taken in the editor are slightly quicker. You also have the ability to tag multiple objects at once. I’ll continue to practise with JOSM on lower priority projects.

Intermediate Mapping - Time to Begin Again

Posted by Uyan on 1 November 2019 in English.

I reached intermediate mapper status on HOT Tasking Manager a few days ago. Now that I’m able to take on tougher projects and validate others’ work, I think now would be a good time to “start again”: learning how to use JOSM to map instead of the online iD Editor. I’ve only used the building label for 90+% of my edits so far but I can see lots of road labellings, as well as rivers and bridges, that I should learn about if I want to become a better mapper. So far I’ve been mapping for 1 hour a day almost daily for the past 2 months. Now I will be taking it slow for a few days while I get to grips with learning a new software.

Today was the usual mapping of buildings. When I went to upload these changes, however, quite a few warning signs came up regarding “tertiary road crosses river”. Usually only a few come up so I can click “ignore this issue” but today there were too many signs to ignore.

I can’t move or delete these rivers as I lack the knowledge on where these rivers run, and I also lack the geographical knowledge to predict where these rivers might run underground, if at all (I don’t move the roads as I can see them and know that they’re in the correct positions). I also don’t know where the mappers of these rivers got their information regarding the locations of the rivers underground unless it was first-hand knowledge from out in the field. If so, it begs the questions as to why there is a lack of labels on buildings nearby the rivers.

Perhaps this issue of roads and rivers crossing is something that mappers already look into at the validation stage. For what it’s worth, I have insufficient experience to be a validator as of yet. All in all I think it is a minor issue, but definitely something that should be looked into after the main bulk of a location is mapped.

Saving Time while Mapping

Posted by Uyan on 12 October 2019 in English.

Today I moved onto some higher priority projects. I saw other people’s styles of mapping and learnt some techniques for improving my own.

The first, and by quite a way the most important, technique was not to map trees or woodland. I thought it would be helpful to map woodland so that aerial emergency services would know where they can and can’t land. However it takes an extremely long time to map all the trees that weave their way through the landscapes of our earth. I suppose at the end of the day they would be able to see with their own eyes if they could land at the scenes of any incidents once they got there. Trees might have been cut down, as well, in the time between the satellite imagery being uploaded and the incidents.

The second, which is more a corollary of the first, is to use less nodes when mapping. It can save some time, but saves an especially long amount of time with regards to woodland; which I won’t be mapping as much from now on, as mentioned previously. Hence there is a good chance that I’ll keep mapping nodes with the same frequency as I used to. Of course there are many objects I have yet to map, rivers would be a notable example, so I’ll revisit this rule of thumb when the time arises.

JOSM - A Different Way to Map

Posted by Uyan on 2 October 2019 in English.

Today I wanted to to learn how JOSM - Java OpenStreetMap Editor - differed in its features from the iD Editor available online. Its main advantages over the fantastic online editor are being able to use it offline, and its advanced features which I have yet to explore. As I become a more experienced mapper I imagine I will find good use cases for the JOSM editor.

Becoming an Intermediate Mapper

Posted by Uyan on 26 September 2019 in English.

Through using HOT Tasking Manager, I’ve noticed that I am currently only able to help with their beginner tasks. Once I have made enough beginner edits, that is when I will be able to move on to more challenging (i.e. intermediate) projects. At the moment I am enjoying the fact that I’m helping map areas in Tajikistan, and I completed 2 squares so far. I will count each square that I complete as a separate project, as I could end up mapping a whole project over the course of the year and only be able to say that I worked on 1 project. Once I get closer to becoming an intermediate mapper - I have to upload 250 edits, and I’ve done around 75 so far, so probably when I uploaded 200+ edits - I’ll study about what makes intermediate tasks more of a challenge over beginner tasks.

When to Give Future Updates

Posted by Uyan on 23 September 2019 in English.

At the moment I’m stilling doing routine building drawings on maps in Tajikistan, so there hasn’t been much of worth to update on. As a result, I think my initial estimation of weekly updates might become fortnightly or even monthly updates, depending on what work I end up doing as time goes by. For example, voluntary work for Missing Maps will primarily be putting buildings on the map. If I then wanted to work on more local mapping, I could take walks around the place to gather public building information (e.g. the name of a pub).

Getting to Grips with Missing Maps

Posted by Uyan on 13 September 2019 in English.

I’ve just found that by initiating projects through the Missing Maps website, your time spent on projects can be timed automatically with a sort of stopwatch feature. This will help me keep track of my contributions to the projects as time goes by. As such I will be cross-referencing this diary and my Missing Maps account, which uses HOT Tasking Manager as the adjudicator.

Missing Maps

Posted by Uyan on 12 September 2019 in English.

I’ve started working on projects for Missing Maps, a volunteering collaboration that puts vulnerable people across the world on the map, with a view to being able to locate them and provide aid to them in the event of a catastrophe or natural disaster. Today I spent 1 hour adding some buildings and nearby habitation in an area of Tajikistan.