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We then introduce novel approaches for the integration of psychoacoustic models in multizone soundfield reproductions and describe implementations that facilitate the efficient computation of complex soundfield synthesis. We first provide a review of the mathematical foundations of acoustics theory, single zone and multiple zone soundfield reproduction, as well as background on the human perception of sound. This thesis answers open questions in the area of personal sound reproduction using loudspeaker arrays, which is the active reproduction of soundfields over extended spatial regions of interest. The concept of, and the ability to provide, spaces of such nature has been of significant interest to researchers in the past two decades. These characteristics have become exceedingly difficult to produce in busy environments such as cafes, restaurants, open plan offices and entertainment venues.

The desired effects of personal acoustic environments can also be areas of minimal sound, where quiet spaces facilitate an effortless mode of communication. Personal sound allows individuals, or small groups of individuals, to listen to separate streams of audio content without external interruption from a third-party. The experience and utility of personal sound is a highly sought after characteristic of shared spaces. The listener can then draw simple and reliable conclusions about the image by quickly decoding the sonified result. To this end, we use perceptually meaningful mappings, in which the properties of an image are directly reflected in the audio domain, in a very predictable way. The proposed system mainly uses musical notes at several octaves, the notion of timbre, and loudness but also uses pitch, rhythm and the distortion effect in an intuitive way to sonify the image content both locally and globally. The sonified signal, which is generated for each position within the image, tries to capture the most useful and discriminant local information about the image content at different levels of abstraction, ranging from low-level (at the pixel level) to high-level (segmentation) and combining low-level (color edges and texture), mid-level and high-level (gradient or color distribution for each region of the image) features. This paper presents a new image sonification system that strives to help visually impaired users access visual information via an audio (easily decodable) signal that is generated in real time when the users explore the image on a touch screen or with a pointer. Results from evaluations of the auditory display with surgeons and surgical assistants confirm that the system is a beneficial addition to image- guided surgery that reduces the dependence of the surgeon on the visual display and increases awareness of risk areas. The auditory display extends the image-guided surgery system by helping guide the surgeon to keep the instrument on the desired resection surface and notifying the surgeon when the instrument approaches nearby risk structures. This thesis presents an auditory display that addresses these two limitations. However, the surgeon must frequently switch between viewing the patient and the computer screen and is often not aware of the presence of anatomical risk areas which may be located near the instrument. Image-guided surgery methods for liver resection are gaining popularity because they allows surgeons to view anatomical structures and planning data on a screen in the operating room as well as view the real- time position of a surgical instrument on a 3D model of the liver.