In the maritime environment, Situational Awareness (SA) is a crucial task for many applications, including the defense ofIn the maritime environment, Situational Awareness (SA) is a crucial task for many applications, including the defense ofthe naval tactical space. In this context, Electro-Optical (EO) sensors and, particularly InfraRed (IR) sensors, contribute tobuilding the Local Area Picture (LAP). The purpose of this study is to face the challenging task of highlighting extendedtargets with respect to the open sea background without any prior knowledge about the size and position within the images.In this work, only single-frame object detection algorithms have been considered. As this task has been extensivelyexplored in the three-channel color image domain, we adapted some color native state-of-the-art strategies on the IRmonochromatic dimension. The algorithms have been tested on a dataset collected through a cooled Medium Wavelength(MW) sensor and an uncooled Long Wavelength (LW) sensor. The ground truth (GT) has been built through directobservation. Each technique has been then evaluated on the two sub-bands images according to broadly used performanceindices.