Failed sequences

I’m using a RTK GNSS receiver (SparkFun Express) connected to an Android smartphone. I capture pictures using Mapillary app. Back, I’m uploading pictures using the app itself and wifi. Time to time, the online processing fail on sone sequences. I’m reporting each failed sequence using email to zendesk. Indeed, I don’t get appropriate answer in that I’m still loosing sequences

Hi Eric,

This particular sequence failed in the initial processing stage. Similar to one of your previous failed uploads, because this sequence failed more than 7 days ago, we are unable to retrieve the data for it, apologies.

So, usually, they answer too late.

Once, they answer quickly :

This sequence (Cluster ID: …) is showing an “invalid GPS data” error. Make sure that your device’s GPS settings are calibrated properly prior to capturing your sequences.

So, I asked for more details:

Can you be more precise on “invalid GPS data”? Does it concern the whole sequence? One or few pictures?

I’m still waiting for answer… and, of course, it was 7 days ago, so they will not be able to investigate.


By strange coincidence, many different people had problems with their sequences over the same period of time

I take photos in OpenCamera for it, and I have it marked that it only takes and saves photos with GPS location. For this I copy them to my computer and send them via Desktop Uploader (which showed all the photo and route without problems).

I measured one sequence, sent it a second time after a month and it was “Failed” second time.

One point for me is that I have not much time a home to transfer pictures. So, back home, connecting to local wifi and starting the transfer from the smartphone is very convenient. In opposite, copying GBs of pictures to desktop PC (usually after extracting SD card from the smartphone because USB transfer is too slow) and later uploading sequences one by one with desktop uploader is a waste of time. It is even worth with OpenCamera because with my smartphone, coordinate are truncated in OpenCamera so I do have to perform geotagging again on desktop with GNSS track, using josm. And, there are time shifts so, for each sequence, I have to adjust time bias using comparison with orthophoto.