1. A device for detecting objects, comprising: a vessel configured to contain the objects to be detected and having a relief bottom; an imager configured to capture an image of the vessel; a vibration unit for displacing the objects contained in the vessel:, a wedging device for wedging the objects in said vessel; a processor configured to process said captured image so as to detect first objects in said at least one captured image, extract characteristics of each detected object of the first objects, and generate a list of the characteristics of each detected object of the first objects; a memory configured to store said generated list, the memory further configured to store a first reference list of object characteristics; and a sensor configured to detect replacement of the first objects in the vessel with second objects in the vessel such that the first objects are no longer in the vessel and to generate a trigger for the processor in response thereto; wherein said processor is further configured to, in response to the trigger: capture a new image of the vessel as containing the second objects and not the first objects, process the new image so as to detect the second objects and not the first objects in the new image, extract characteristics of each detected object of the second objects in the new image, and generate a second list of characteristics from the new image, and compare characteristics of each object from the second list with, respectively, the characteristics of each object from the first reference list to determine correspondence between the objects in the new image and the objects in the image.