Augusto Sarti

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This paper describes an audio-based video surveillance system which automatically detects anomalous audio events in a public square, such as screams or gunshots, and localizes the position of the acoustic source, in such a way that a video-camera is steered consequently. The system employs two parallel GMM classifiers for discriminating screams from noise(More)
This paper describes an audio event detection system which automatically classifies an audio event as ambient noise, scream or gunshot. The classification system uses two parallel GMM classifiers for discriminating screams from noise and gunshots from noise. Each classifier is trained using different features, appropriately chosen from a set of 47 audio(More)
Acoustic scene reconstruction is a process that aims to infer characteristics of the environment from acoustic measurements. We investigate the problem of locating planar reflectors in rooms, such as walls and furniture, from signals obtained using distributed microphones. Specifically, localization of multiple two- dimensional (2-D) reflectors is achieved(More)
In this paper we propose a method for reconstructing the 2D geometry of the surrounding environment based on the signals acquired by a fixed microphone, when a series of acoustic stimula are produced in different positions in space. After estimating the Times Of Arrival (TOAs) of the reflective paths, we turn each TOA into a projective geometric constraint(More)
In the past few years, a number of practical video coding schemes following distributed source coding principles have emerged. One of the main goals of distributed video coding (DVC) is to enable a flexible distribution of the computational complexity between the encoder and the decoder, while approaching the coding efficiency of conventional closed-loop(More)
The wave digital filter (WDF) theory provides us with a systematic methodology for building digital models of analog filters through the discretization of their individual circuit components. In some situations, WDF principles can also be successfully used for modeling circuits in which a nonlinear circuit element is present under mild conditions on its(More)
This paper focuses on a new geometric approach to (fully actuated) control systems on the sphere. The control laws exploit the basic and intuitive notions of geodesic direction and distance between points, and generalize the classical proportional plus derivative feedback (PD) without the need of arbitrary local coordinate charts. The stability analysis(More)
Current physics-based synthesis techniques tend to synthesize the interaction between different functional elements of a sound generator by treating it as a single system. However, when dealing with the physical modeling of complex sound generators this choice raises questions about the resulting flexibility of the adopted synthesis strategy. One way to(More)
A new recursive technique for the synthesis of a -order inverse of a Volterra system is presented. In such a method, the condition that the p‘ -order inverse be exactly of order p , as proposed by Schetzen, is relaxed. The choice of the residuals, that is the operators of the inverse whose order is higher than p , is done with the purpose of reducing the(More)
The physical modeling of complex sound generators can only be approached by individually synthesizing and discretizing the objects that contribute to the generation of sounds. This raises the problem of how to correctly implement the interaction between these objects. In this article we show how to construct an object-based environment for sound generation,(More)