1. A target object detection system comprising: a detection unit which is configured to obtain an image, to perform an operation associated with classification using weak classifier parameters so as to determine whether a portion of the image resembles a target object, and to output the image, said detection unit being further configured to output a notification signal when it is determined that the portion of the image resembles the target object; and a machine learning unit which is communicably coupled to said detection unit for receiving the image, and which is configured to perform operations associated with classification using the weak classifier parameters and strong classifier parameters, respectively, so as to make respective two determinations as to whether the portion of the image resembles the target object; wherein said machine learning unit is further configured to, when results of the respective two determinations are different, perform a training operation using the image so as to obtain new weak classifier parameters which is used to update the weak classifier parameters of said detection unit and of said machine learning unit.