I have thought about this for a while, so I'll throw it out and please comment.
Sooner or later Mapillary would have to make a feature to classify images. Some areas are so saturated that navigating is very slow (I have contributed to this myself) and some series are pretty bad but better than nothing (I have also contributed to this) but better series may have been added later (I too have done this).
In short: Using all images does not always give a good result and the selection should not be random if possible.
So how to do it?
Imho there should at least be a classification that only looks at technical quality of the image. This allows for the same measurement to be used everywhere to select the best of the possible next pictures.
What do I mean by technical quality?
- Is the image well exposed - not too dark or light?
- Is the image sharp? Not too blurry due to e.g. bad focus or movements.
- Is the image clear of unwanted objects like dust, rain drops, bugs on the window, reflexes in the window, my fingers or the dashboard?
- Are the colors ok?
- Is the image straight, i.e. not tilted because a bike is turning?
- Is the resolution reasonable? One of my action cams only does about 2 mega pixels, which is not that much.
Personally I would grade each image from 0 to 5 (stars?), with 5 being the best. A 5 is a technically perfect image with a sharpness that is what you can expect form a phone or action cam.