OpenStreetMap

Mapillary seems to be Losing It’s Marbles

Posted by alexkemp on 9 February 2019 in English (English)

Mapillary is a location-photo-sharing site dedicated to inter-working with OSM & I like it a lot.

Mapillary is the street-level imagery platform that uses computer vision to fix the world’s maps.
450.7 million images; 6.5 million kilometers covered

I am registered on Mapillary since Apr 10, 2016 and it tells me that in that time I have uploaded 6,200 photographs shot whilst walking across 244.7 km of Nottingham’s suburbs. Most of those photos are registered as links with various PoI on the map, which means that someone browsing OSM can find a link attached to a Nottingham point-of-interest that will instantly let them see a blurred photo of what it looks like 32% of the time.

Blurred Photos

At the moment that I am writing these words the following photo has 33 auto-blurs attached to it, 32 of which affect the street-sign on the right (the 33rd is on the brickwork to the right):–

blurry street-sign

At this moment I am going through each & every one of those 6200 photos removing the stupid-blurs. Nothing will happen until at least next Monday (11 Feb), as all the blur-removals are actually blur-removal requests (a Mapillary admin has to agree/refuse the request).

33 blurs is bad, but not the worst - one photo had more than 40 blurs (a patch of shrubbery) (whilst another just now had 45 all on top of another street sign), all of which were stupid-blurs.

So what is going on?

Mapillary has always edited uploaded images before showing them:–

What Mapillary blurs:

  • Faces
  • Vehicle license plates
  • Inappropriate or private parts of the image

What Mapillary does not blur:

  • Whole people
  • People from behind when the face is not seen
  • Billboards, advertisements, brand labels
  • Street, traffic and information signs

So what is the problem?

I have zero problem with Mapillary enforcing privacy blurs. I’ve dealt with too many MPGs spontaneously combusting just because I’m stood outside their house asking if I may take a photo of their house-name not to know that the English have a particular issue with Google StreetView (if you get my drift through all those disparate topics).

In the early days Mapillary kept blurring out street-signs, and it has taken quite a few years for them to stop doing that. Most of the time now it seems to work OK. However, the Blur Algorithm appears to have recently been put onto steroids, in that it is blurring areas so small that they can barely be seen. Worse, the programming has schoolboy-level errors; as just one example, some of the street-sign blurs are quite large yet inside that area may be yet another 5 smaller blurs - what is the point of that?

Look at the photo below; it is the example used in the help-page to illustrate what the privacy-blur edit-page looks like. Those orange/green/white numbered circles locate the presence of a blur enabled by the Mapillary privacy-bot.

Mapillary privacy-blur edit-page

Each blur has to be removed one-by-one using a mouse, no keyboard allowed. This is tedium ratched-up to mind-numbing proportions.

  1. Hover over a blur
  2. Move the mouse up to a combo of green tick✔ + orange cross✘ that then appears
  3. Hover over & click on the cross
    (maybe you are hovering over the cross, maybe not)
  4. Next blur…

My constant experience across the last two days has included a bunch of 5-or-more of those circles located on top of each other in such a fashion that I cannot click on the ones underneath. Or of circles located under image navigation features (arrows & chevrons, forward/back arrows or attribution-feature); those are all located in top-of-z-order, which means that nothing underneath them can be clicked on. These are what I am calling “stupid-blurs”.

The Modified Date for the Blur Help Page is January 09, 2019 13:01 (there is a set of blurs on all earlier photos in addition to these recent blurs; those earlier blurs are no longer editable). I therefore assume that the blur-bot was very recently unleashed on all 451m Mapillary photos to enforce further blurs. Or, more accurately, further stupid-blurs. Get more intelligent more quickly, please, Mapillary-bot!

Stats

Being a scientist I thought some measure of the problems was required.

I’m working my way from latest to earliest and have already gone through 26 sets of photos. Here are the accumulated stats from the 27ᵗʰ set of 111 photos, shot on 31 January 2017 in the streets near Phoenix Avenue close to Gedling:–

  • Total photos: 111
  • Contains blurs: 35 (32%)
    (following applies to blurred photos only)
  • smallest # blurs: 1
  • largest # blurs: 25
  • Total blurs: 233 (avg: 7/photo)
  • Valid blurs: 19 (8%)
  • Stupid blurs: 214 (92%)

Addendum

Tues 12 Feb: Mapillary have sent me an email to say that the team is looking at it.

Location: Arnold and Carlton, Gedling, Nottinghamshire, East Midlands, England, United Kingdom

Comment from westnordost on 17 February 2019 at 15:41

I hope the blur-algorithm is actually a machine-learning one, so your corrections actually make the algorithm better.

Comment from alexkemp on 17 February 2019 at 15:54

Hi westnordost

My recall from early days is that yes, it is a so-called intelligent algorithm. I certainly hope so, since that is the reason that I keep plugging away making the edits.

My main worry is that there has been zero feedback (support says “I have fed your comments to the developers”, but nothing other than that) & zero changes to edited photos. This means that I am unsure whether my edits are even connected to Mapillary & their routines at all.

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