Ambient Intelligence in Urban Environments

This paper reports advances achieved within a project called LAICA (Laboratorio di Ambient Intelligence per una Città Amica) on Ambient Intelligence in urban environments. The overall LAICA architecture is described and the unified operative centre developed by Regulus SpA (partner of the project) to collect and correlate data from different sensors and prototypes is depicted. Moreover, the paper describes the results obtained in developing a system for video surveillance in public parks, devoted to create a mosaic image of the scene and to extract and track moving people. Moreover, the system takes the privacy issues into account, proposing a method for face detection and tracking able to obscure faces in order to protect people’s identity. 1. The LAICA Project This paper reports on a project called LAICA, acronym for Laboratorio di Ambient Intelligence per una Città Amica (in English: Laboratory of Ambient Intelligence for a Friendly City). This is a two-years (2005-2006) regional project that involves universities, industries and public administrations. The main aims of the LAICA project are to define innovative models and technologies for Ambient Intelligence in urban environments, and to study and develop advanced services for the citizens and the public officers in order to improve personal safety and prevent crimes. This multi-disciplinary project brings together the academic expertise and the industrial knowledge into several fields, from the low-power sensor networks, to the computer vision, to the middleware and mobile agents, to the communication. The foreseen services should be provided by a set of prototypal systems, as for instance: − a system for the automatic monitoring of pedestrian subways by means of mobile and low-power audio and proximity sensors 1; − a system for the automatic monitoring of traffic scenes by cameras for data collection and web-based delivery of traffic news to citizens and police officers 2; − a system that generates a feedback in pedestrian crossing systems to select the best duration of the green signal for the crossing 3; − a system for the automatic monitoring of public parks with a plethora of cameras (both fixed and PTZ pan/tilt/zoom) 4; − a platform of Urban TV to broadcast in interactive ways the data to the citizens 5. The project represents a suitable platform for exploring different paradigms of Ambient Intelligence (AmI). Ambient Intelligence is the new multi-disciplinary field that brings together sensor fusion, computer vision, middleware, multimedia and many other research fields. In fact, these prototypes are meant both to analyze the urban environment, collecting statistics or reporting on alarming situations (in the case of traffic analysis and public park surveillance), and to control it (providing a feedback to actuators, as in the case of the traffic lights for pedestrian crossing). Additionally, they can interact with the environment, allowing the citizens to access to real-time multimedia information on the status of the city. 1 Studied and developed by the Micrel lab at DEIS – University of Bologna, in collaboration with Wavelet Technology Italia SrL 2 Developed by Wavelet Technology Italia SrL, Regulus SpA and OT Consulting SrL 3 Studied and developed by the Artificial Vision and Intelligent Systems lab at DII – University of Parma 4 Studied and developed by the Imagelab lab at DII – University of Modena and Reggio Emilia 5 Studied and developed by the DSC – University of Modena and Reggio Emilia The LAICA project has been structured with a three-layers architecture, corresponding to three different level of granularity of the knowledge provided by sensors. The test bed of the whole LAICA project is the city of Reggio Emilia, in Italy, whom municipality is active partner of the project. The project starts from the exploitation of the existing network of sensors (consisting of hundreds of cameras for surveillance purposes and intelligent sensors in road intersections and subways) and available infrastructures (hundreds of kilometres in fibre channels for transmission at large bandwidth) deployed in Reggio Emilia. However, the above mentioned sensors are of different degree of complexity and computational power, ranging from the simple sensors for environmental measurements, to matrix of proximity, temperature and positioning (GPS) sensors, to fixed and moving cameras. All these sensors are connected through a MAN or wireless networks in order to communicate useful information to an operative centre or to be queried by a human operator. SIRTI SpA and Agactel SpA have in charge the deployment of the infrastructures useful for the connectivity of the different parts of the project. In this scenario, the foreseen architecture of LAICA is composed of three layers (see Fig. 1): 1. punctual layer (pointAmI): the AmI system is seen as a distributed collection of low-level sensors and actuators. These points of sensing and control can be singularly queried, possibly also through mobile devices, such as PDA or last-generation cell phones. For instance, it will be possible to look at a specific camera, or querying the state of the traffic at a specific intersection, and so on. The system sends the requested data with a point-to-point connection; 2. local layer (localAmI): the AmI system can be seen as a cluster of sensors, dynamically reconfigurable. The expert (and authorized) users can define their own set of sensors. For example, a traffic light system can be a collection of cameras, inductive loops and proximity sensors, and of several actuators too. A citizen may want to query the state of the traffic light in its entirety, as a localized set of entities. Despite its locality, the set can require distributed processing and coordination, and must be accessible. Middleware with distributed agents will be developed for this aim; 3. global layer (globalAmI): the whole AmI system must be able to interact with the environment and to collect data from distributing sensing. The global knowledge is handled by an operative centre described in the following. GlobalAmI LocalAmI PointAmI Fig. 1. The three layers of the LAICA AmI architecture. In this scenario, each sensor or cluster of sensors must have a sufficiently high computational power to extract useful information from the scene. The main aspect of the project is that it has been considered as a cooperative research and industrial project with strong interactions among the actors in order to implement a real AmI framework. It is not merely a sum of services, but, conversely, the services and systems (some standards, some innovative for a public administration) will exploit their synergies, share communication supports and collecting servers, and be accessed concurrently as a single unique intelligent centre of monitoring of urban environments. 2. The LAICA operative centre Fig. 2. A snapshot of the Regulus system for operative centre management Road security and conditions, territory control and citizens safety, integrated road haulage, environment and pollution, are relevant and debated topics, not only at national and European level, but also at local level (city, province and region). An Ambient Intelligence software platform enables the concurrent focus on all these topics; in this context, Regulus has developed a local Operative Centre (Fig. 2) that is the right solution to manage unexpected and planned events and activities; the Operative Centre is the final point to store and to manage information. The Operative Centre (O.C.) has to integrate and to coordinate an intelligent network, made by sensors and devices (audio sensors, movement sensors, video cameras, etc.) distributed around the local area. These sensors and devices provided with distributed intelligent algorithms, using a wired or wireless connection, are able to signal critical events to the O.C. (a road accident, traffic jam, ice, suspicious and dangerous situations, etc.) or to signal data (counting vehicles, accessing city centre, etc.) in charge of activate all the means at its disposal. The O.C. has a component-based architecture; each component is a solid, independent working unit, able to cooperate with the other components using standard and well-defined interfaces. Using this approach it’s possible to start with the needed functions and to increase and to integrate more components according to security and safety plans. The base components are: • Localization sub-system: in charge of finding the position for personnel and vehicles, using digital maps and GPS system, exchanging data and messages. • Management sub-system: in charge of managing personnel, vehicles, activities, calls from citizenship and operators, etc. • Communication sub-system: in charge of connecting devices, sensors, vehicles and personnel. Different infrastructures could be used, for example: Radio, GSM/GPRS, TETRA and UMTS. Other important components are: • Historical sub-system: in charge of retrieving all the data managed by O.C. • Statistical sub-system: in charge of creating textual or graphical presentation about the data store in database, according to filters inserted. • Duties sub-system: in charge of settling the work shift for the personnel, vehicles and other assets. Moving from an Operative Centre to a Unified Operative Centre (U.O.C.) is the natural evolution to address in the right way security and safety problems. Integrating different Departments inside the same local authority (for example local police civil guard road service), or connecting different Authorities (for example local police national police) are the next steps to move towards a U.O.C. Each department or authority will maintain its autonomy; nevertheless if data or information is common and important, immediately will be shared among all the operators. Of course Operative Centres, both at technological and behavioural level, have to respect citizenship: • Taking care privacy laws a