Move by a specified distance

[mvglasow]

When mapping milestones, I often need to move forward (or backward) by a specified distance—100 m, 500 m or 1000 m—and skip over the images in between. Currently I either have to guesstimate the approximate distance between two images, divide the desired distance by that number and click Previous/Next that many times, or measure the desired distance out on the map and specifically select the nearest image in the map view.

Two improvements which would help me a lot:

• have the Previous/Next buttons display the actual distance to the respective image
• add a way to move back/forward not by one picture, but by a specific (user selectable) distance

[eneerhut]

@mvglasow just curious to understand the use case a bit better. What do you mean by milestones?

Also, what do you think of the solution to navigate across the sequence in the web UI?

[mvglasow]

By milestone I mean kilometric point indicators on roads, something like this:

https://commons.wikimedia.org/wiki/File:Dk9_o2.jpg
https://commons.wikimedia.org/wiki/File:Cholupice,_Pra%C5%BEsk%C3%BD_okruh,_kilometrovn%C3%ADk_p%C5%99ed_mostem_Hrazansk%C3%A9_ulice.jpg

Similar markers are found along rivers and railroads, some of which also have Mapillary sequences.

As for the web UI, a few points: I normally don’t use playback mode but jump to an image near the position I am interested in, then move back or forth as needed until I have the last image before the milestone.

I’m not sure I understood the part about the web UI. The rabbit icon, I assume, controls playback speed and direction (“move one image forward/backward every X seconds”), but has nothing to do with distance (such as “show me the image 500 m after the current one”). I haven’t been able to figure out what the icon next to it does.

Also, if I can easily find the image I am looking for in the web UI, how would I then select the image in JOSM (so I have the exact coordinates where the image was taken)?

[eneerhut]

Thanks for clarifying @mvglasow.

@mvglasow in the screenshot, I was mainly referring to the slider that allows you to navigate easily between the start and end of the sequence. It doesn't allow you to specify a distance, but it does make it easier to move a significant distance within the same sequence.

If you find the image you are looking for in the web UI, you can open that location in JOSM using 'Image options' and then 'Edit via JOSM'.

[mvglasow]

My current workflow is: find an already-mapped milestone or find a picture of the first one, then map it based on the picture. Select the milestone while in line-drawing mode and abuse the line as a tape measure to find a location down the road which is slightly closer than the usual spacing between two milestones (measured as the crow files), then switch to selection mode and choose the closest image. Then cycle through images one by one until reaching an image of the next milestone.

That is, based on the location of a milestone I know where the next one is likely to be. To map the milestone, I need the exact location of the picture showing it.

The web interface is a bit crude for that. Moving forward in the sequence via the slider doesn’t show me any distance information, making it a guessing game. Editing in JOSM presumably relies on the Remote Control plugin, which downloads certain area around the image location and zooms there. Again, that is much less precise than knowing the exact image location, and the download is undesirable if I am e.g. working with data from Overpass API rather than a full download. Altogether, that is less precise than my current workflow and doesn’t really save me a lot of work. Distance information in meters is what I am really missing here—skipping a large number of images is not the issue.

[eneerhut]

Thanks @mvglasow. Workflow is well understood. I guess we need to see what similar use cases come up where set distance between images is a useful feature. That would help determine the level of priority for this feature request.