On the Describe page of a Data Source, trajectories of all vehicles/cyclists/pedestrians from the traffic scene are presented on the preview screenshot. That provides a straightforward overview of how the traffic situation on the scene looks like.
After creating some filters (lines, zones) you can define desired traffic movements. By using filters, you can examine the trajectories only for a selected movement or just for some object classes. This is useful on rich and more complex scenes, where it is sometimes difficult to get a quick overview. In case of videos longer than 1 hour, the movement trajectories are filtered out and show a 1 hour sample. That keeps the movement flows on the describe page consistent and assures fast presentation of the results for your analysis.
However, sometimes it might be useful to see complete trajectories also for particular movements. That’ s what the Trajectories widget does. If you ‘d like to show all trajectories of each object in the video on a specific filter, you can create the Trajectory widget for the chosen movement. You’ ll find the graphical output on the Analyze page afterwards and download the snapshot if necessary.
Example of pedestrian trajectories crossing a city street