Abstract: In some aspects, the techniques described herein relate to a method that includes: obtaining optical channel spectrum data that includes amplified spontaneous emission data and channel data associated with optical signals propagated through an optical fiber; fitting an amplified spontaneous emission trend to the amplified spontaneous emission data; fitting a channel trend to the channel data; jointly optimizing the amplified spontaneous emission trend and the channel trend to determine an optimized channel trend; and determining an anomaly in the channel data based upon the optimized channel trend.

Abstract: A detection device (1) including: a sensor configured to emit a monitoring signal representing a scene (S), a control unit (4) connected to the sensor. The control unit is configured to: receive the monitoring signal from the sensor, estimate a three-dimensional representation of the scene (S) as a function of said monitoring signal, determine an inspection region (V) from the three-dimensional representation of the scene, provide a classifier with a representation of the inspection region (V), determine, by means of the classifier and based on the representation of the inspection region (V), the presence of people (P) and/or specific objects (C) in the representation of said inspection region (V).