Pipeline overview#

TODO

First Iteration: Principle and Workflow#

The pipeline consists of several components.

../_images/workflow.png

Figure 1. Processing steps of the first pipeline iteration#

(1) First, GNSS trajectories are segmented and resampled to obtain homogeneous trajectories with respect to spatial and temporal resolution.

(2) Next, a synthetic representation of trajectories is generated through a grid-based processing approach, producing a heat map that highlights both major routes and secondary paths.

(3) This raster representation is then transformed into a vector skeleton, i.e., a graph whose edges represent the central axes of the identified movement corridors, using skeletonization operations.

(4) For each edge of the skeleton, the associated GNSS points are identified through map-matching operations. These points are subsequently grouped into trajectory segments, providing for each edge a set of individual traces to be compared and merged.

(5) The segments associated with a given edge are then merged in order to reconstruct as accurately as possible the common path followed by the different individual trajectories.

(6) Finally, a geometric adjustment step ensures the continuity of the reconstructed segments while preserving the topology of the skeleton, thereby producing the final mobility network.

Raw Trace Preparation#

GNSS trajectories are segmented and resampled to obtain homogeneous trajectories with respect to spatial and temporal resolution.

..=> produit un jeu de traces, résolues spatialement à 1 mètre,

extraites (peut-être découpées) suivant une figure géométrique

Calcul d’une carte de densité à partir des traces GNSS#

Calculs des cartes de densité, de contraste et binaire à partir des traces GNSS

=> produit un jeu de traces résolues spatialement à 1 mètre

  • De la vectorisation on extrait une ligne centrée ≡ arc de la topologie

avec Filtre morphologique, Vectorisation, Squeletisation

Calcul de la topologie du réseau#

Calcul de la géométrie des arcs du réseau#

Conflation des traces fusionnées#

Correction élastique de la géométrie du réseau

Itérations et embranchements#