Every day becomes more common to hear about IoT (Internet of Things), in which objects are interconnected by a network like WiFi have the capability to produce and exchange information. In this same scope we have smart cities, where technologies cooperate to create benefits for citizens. Among the various topics of smart cities one of the most important is urban mobility. Based in this context, the project aims to work with a part of this system, in order to develop an autonomous and integrated traffic light system capable to detect and process traffic flow by controlling the traffic lights using a image processing algorithm to count the vehicles.