Turn a Tesla into a mapping vehicle with Mapillary

Summary

About two years ago, Tesla enabled a dashcam feature in their vehicles, which allows Tesla drivers to access the imagery collected by the vehicle’s cameras. The mode of operation is simple: plug a USB stick in one of the vehicle's USB ports, and imagery will be saved to the USB stick automatically. The task of getting imagery to Mapillary then boils down to getting the images stored on the USB drive to Mapillary. Geotagging The main challenge to overcome is that Tesla does not store the GPS tracks alongside the videos on the USB drive. This means that we need to get the GPS signal from another source. The simplest way to achieve this is to use one of the GPS tracking apps available for your phone. If you download the GPS (GPX) track files to your PC alongside the clips from your dashcam, you can use Mapillary’s standard tools to align the video clips with the GPX tracks. This is achieved by associating the capture time of the video clips with the timestamps in the GPX track. Luckily, the Tesla dashcam stores a timestamp with second precision in the filename of each video clip: Our strategy is then to align the video with the GPS track. Before we go there, I’d like to add a few comments on what type of GPS tracking app works best: Simple start and stop with a single button to simplify recording while driving GPX export with a file format that mapillary_tools can use Correct time, timezone, and format for GPS recording and GPX file (GPX standard is to write time in UTC) Easy way to get the files to your PC (email sharing, Apple AirDrop etc.) High enough save frequency between GPX timestamps (for driving in a car rather than say walking) Sampling video and aligning with the GPX track Our strategy to get the videos aligned with the GPX tracks and images for upload extracted is as follows: We can use Mapillary’s command line tools to sample a video clip into frames using the process_video command. We use the video_start_time parameter to set the correct capture time for ...