Subsecond Workflow

Hi,

I wanted to as if there is already a successfule workflow out there for treat images taken by an action camera (mine is the Xiaomi Yi) taken with a 0.5s interval.

I stumbled upon several discussion, but without any “clear”-solution, without a lot of try-and-error.

I found the script von @blaueente which can be found here ( https://github.com/mapillary/mapillary_issues/issues/1319#issuecomment-139901432 )

But unfortunately, there is no comments if this approach can be handled right by the scripts and Mapillary itself.

Also, the script inserts the EXIF-tag “Date/Time Original” twice, which I’m not sure how mapillary will handle this ambiguity.

If someone has already a workflow/scripts ready and in use and made good experiences, would be really kind if you could tell me about it.

I wrote a script to calculate the average interval between pictures and rewrite the timestamp in the exif data.
It is one of my first python script and it’s a “dirty” one, but you can try it :
https://github.com/Stefal/V4MPod/blob/master/scripts/intertime.py

I think I won’t improve it as I’m working on a completely different way to handle the timing.

@canadarunner I may have misunderstood your question because I’m not so experienced with scripts myself. But as much as I’ve heard, the ones in mapillary_tools are well capable of handling 0.5 s interval timing… Have you tried and/or what kind of trouble did you run into?

@katrin, well the main problem is, that my camera doesn’t write subsecond information into the EXIF metadata.
Now the main problem is, that when I’d like to georeference my images, all images which are taken at the same second (but not subsecond) will be map onto the same location.

I never tried the mapillary_tools itself, because already the subsecond interpolation caused some problems.

As described in the beginning, the tools from @blaueente worked, but with this EXIF-tag which appears twice, I’m not absolutely sure, that I don’t confuse mapillary.

Hm. I hope someone more script-wise can help you. I can only suggest that you do a little “test drive” and upload a sample of whatever you are wondering about via the web uploader. Then you’ll just see how it behaves on Mapillary… Can always delete the sequence later if it goes to hell.

For my education, do I understand correctly that your camera seems to be able to capture at 0.5 sec frequency but then does not have a timestamp with a greater precision than a full second?

Hi, yes I will do it if I find time.

Yes that’s absolutely true, my camera supports timelapse with a 0.5s interval, but unfortunately doesn’t write this subsecond capture time not into the EXIF

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