Hi! I am using my camera to provide best quality imagery. It features the interval function, so it takes one image per five seconds. Sometimes, I have to abort it because people or cars are crossing (and begin a new interval recording). When I used my phone, I experienced that when I upload (via Desktop uploader) one batch, it split it into several Mapillary sequences, although they belong together. Is there a way to force one upload to become one Mapillary sequence? Thanks in advance
They must be very close to each other I think
Sequences will always be split into 1000 images, that’s the maximum sequence size.
Using the command line tools. I would suspect the desktop uploader can also configure these;
There are various parameters invoking the tools that will “split” a sequence and “force” creating duplication errors that drop those that are too close in time or distance. The command line help for “process” for example;
–cutoff_distance CUTOFF_DISTANCE
Cut a sequence from where the distance between
adjacent images exceeds CUTOFF_DISTANCE. [default:
100.0]
–cutoff_time CUTOFF_TIME
Cut a sequence from where the capture time difference
between adjacent images exceeds CUTOFF_TIME. [default:
60.0]
–duplicate_distance DUPLICATE_DISTANCE
The maximum distance that can be considered “too
close” between two images. If both images also point
in the same direction (see --duplicate_angle), the
later image will be marked as duplicate and will not
be upload. [default: 0.1]
–duplicate_angle DUPLICATE_ANGLE
The maximum camera angle difference between two images
to be considered as heading in the same direction. If
both images are also close to each other (see
–duplicate_distance), the later image will be marked
as duplicate and will not be upload. [default: 5.0]
I would suggest in your case of the photos in a date/time ascending file name set, use some numbers like;
–cutoff_distance 100 (100m maximum between photos)
–cutoff_time 3600 (1 hr max between photos. Check such a large number works though)
–interpolate_directions (You probably manually set the image direction so make sure this is not included)
–duplicate_distance 0.01 (10mm minimum movement between each frame. Check such a small number works though)
–duplicate_angle 90 (so it wont drop frames if you rotate the camera around close to the same point with a direction change of <90deg)
Hope this helps.
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Thank you, this sounds reasonable! The position alone is probably not the problem, as I was next at the sequence when I aborted it. I also saw image sequences containing more than 1000, or they used command lines. Anyway, I was not near that limit
It’s also worth knowing that if (before Mapillary process) the photos have the GPS position (and probably direction) already saved in EXIF the actual date is not so important and a GPX etc isn’t needed. AFAIK the tools won’t care about anything but the lat/lon and date/time order. ie it’s possible to merge a specific route from a number of source dates/times and fabricate a date/time from (say) the filename. eg;
20260321_010101_555.jpg might represent March 21 2026, 1:01:01.555
Then use exiftool to change the date/time fields;
exiftool -P -overwrite_original ‘-alldates<filename’ ‘-SubSecTime*<${Basename;m/(\d+$)/;$=$1}’ ./
One would have to be careful with vastly different light conditions (that might affect object recognition) and use a date and time that is reasonably close, but it is then possible to create a series of images as if it was just one pass, from more than one.
Not sure if this may help for your workflow method, but thought worth a mention.