Method and device for determining concealed objects in a 3D point cloud representing an environment

A device for determining concealed objects in a 3D point cloud representing an environment, comprising:

• an active sensor;
• and
• an evaluation unit;
• wherein the evaluation unit is configured to determine concealed objects in a 3D point cloud representing an environment, the evaluation unit configured to:
• produce a 3D point cloud using the active sensor, wherein each point of the 3D point cloud represents a distance measurement by the active sensor,
• determine a background region within the 3D point cloud,
• determine shadows within the background region of the 3D point cloud, wherein the shadows are regions within the background region at which there are substantially no points of the 3D point cloud, and
• determine, in an environment of the active sensor, an object which is concealed by crosstalk in the active sensor, by identifying, in the background region of the 3D point cloud, at least one shadow which cannot be attributed to an object in a foreground of the 3D point cloud,
• wherein a type and/or a size and/or a position of the concealed object is determined based on a characteristic of the shadow produced by the object,
• wherein the information about the shadow, determined in the background region, of the object concealed in the foreground is used to add points representing the concealed object to the 3D point cloud in a region of the foreground in which the concealed object was determined, and
• wherein a dead time of a detector of the active sensor is taken into account when determining a depth extent of the region in which points representing the concealed object are added in the 3D point cloud.