Natural sound rendering for headphones: . . .

With the strong growth of assistive and personal listening devices, natural sound rendering over headphones is becoming a necessity for prolonged listening in multimedia and virtual reality applications. The aim of natural sound rendering is to recreate the sound scenes with the spatial and timbral quality as natural as possible, so as to achieve a truly immersive listening experience. However, rendering natural sound over headphones encounters many challenges. This tutorial paper presents signal processing techniques to tackle these challenges to assist human listening

Etäisyyden huomioiva kaksiulotteinen viivakoodi mobiilikäyttötapauksiin

Global internet use is becoming increasingly mobile, and mobile data usage is growing exponentially. This puts increasing stress on the radio frequency spectrum that cellular and Wi-Fi networks use. As a consequence, research has also been conducted to develop wireless technologies for other parts of the electromagnetic spectrum – namely, visible light. One approach of using the visible light channel for wireless communication leverages barcodes. In this thesis, we propose a 2D barcode that can display different information based on the distance between the barcode and the scanner. Earlier research on distance-sensitive barcodes has focused on providing a closer viewer more information as a closer viewer can see more detail. In contrast, we target use cases where a clear physical separation between users of different roles can be made, such as presentation systems. We evaluate two methods of achieving distance-awareness: color-shifting of individual colors, where a color changes tone at longer distances, and color blending, where two colors blend into a third color at longer viewing distances. Our results show that a modern smartphone is capable of leveraging color-shifting in ideal conditions, but external changes such as ambient lighting render color-shifting unusable in practical scenarios. On the other hand, color blending is robust in varying indoor conditions and can be used to construct a reliable distance-aware barcode. Accordingly, we employ color blending to design a distance-aware barcode. We implement our solution in an off-the-shelf Android smartphone. Experimental results show that our scheme achieves a clear separation between close and far viewers. As a representative use case, we also implement a presentation system where a single barcode provides the presenter access to presentation tools and the audience access to auxiliary presentation material.Maailmanlaajuinen internetin käyttö muuttuu yhä liikkuvammaksi, ja mobiilidatan käyttö kasvaa eksponentiaalisesti. Tämä kohdistaa yhä suurempia vaatimuksia radiotaajuusspektriin, jota mobiili- ja Wi-Fi-verkot käyttävät. Näin ollen tutkijat ovat kehittäneet langattomia teknologioita hyödyntäen myös muita sähkömagneettisen spektrin osia – erityisesti näkyvää valoa. Yksi näkyvän valon sovellus langattomassa viestinnässä ovat viivakoodit. Tässä työssä kehitämme kaksiulotteisen viivakoodin, joka pystyy välittämään eri tietoa katselijoille eri etäisyyksillä. Aiempi etäisyyden huomioivien viivakoodien tutkimus on keskittynyt tarjoamaan lähellä olevalle katselijalle enemmän tietoa, koska läheinen katselija näkee viivakoodin tarkemmin. Sitä vastoin me keskitymme käyttötapauksiin, joissa eri käyttäjäroolien välillä on selkeä etäisyydellinen ero, kuten esimerkiksi esitelmissä puhujan ja yleisön välillä. Tarkastelemme kahta menetelmää: yksittäisten värien muutoksia etäisyyden muuttuessa ja kahden värin sekoittumista etäisyyden kasvaessa. Tulostemme perusteella nykyaikainen älypuhelin pystyy hyödyntämään yksittäisten värien muutoksia ihanteellisissa olosuhteissa, mutta ulkoiset tekijät, kuten ympäristön valaistus, aiheuttavat liian suuria värimuutoksia käytännön käyttötapauksissa. Toisaalta värien sekoittuminen on johdonmukaista muuttuvassa sisäympäristössä ja sitä voidaan käyttää luotettavan viivakoodin luomisessa. Näin ollen me suunnittelemme etäisyyden huomioivan viivakoodin hyödyntäen värien sekoittumista. Toteutamme ratkaisumme yleisesti saatavilla olevalle Android-älypuhelimelle. Kokeellisten tulostemme perusteella menetelmämme saavuttaa selkeän erottelun läheisten ja kaukaisten katselijoiden välillä. Esimerkkikäyttötapauksena toteutamme myös esitelmäjärjestelmän, jossa sama viivakoodi antaa lähellä olevalle puhujalle nopean pääsyn esitystyökaluihin ja kauempana olevalle yleisölle pääsyn esityksen apumateriaaliin

The Aural and the Quotidian: Everyday Experience in Listening and Practice

The research herein comprises an examination of the following question: in what ways do our experiences of the everyday inhere in our experiences of the aural as aesthetic and meaningful? It is not concerned with forging a definition of everyday sound as a category of sonic effects, but instead an analysis of the ways that the everyday, aural and otherwise, is interpenetrating with our perceptual capacities and the cultural practices encompassing aural aesthetic production and experience. This thesis extends extant discourses surrounding the notion that the experience of sound as meaningful and aesthetic is connected to our general experience as embodied beings in the material world. The following analysis encompasses aspects of auditory perception, music aesthetics, and sound art production from the perspective of the body, as it is the locus of the listening subject situated within the domain of everyday experience. This includes an investigation of sound transduction technologies, as the devices that enable aural aesthetic practice are central to its analysis in the context of the everyday. Listening attitudes are transformed through cultural practice, structuring the relationship between the domain of the everyday, the embodied listening subject, sound recordings as cultural artefacts, and the attendant process of transduction. Discourses that attribute non-material, disembodied understandings to aesthetic experience are examined and challenged. From this, a fundamentally material, embodied approach to auditory experience is proposed, and with it a consideration of the ways that sound art and acousmatic music engage with the process of human understanding and the constitution of meaning in sound. Self-reflexive methodologies in aural aesthetic practice are exemplified, with the aim of promoting an expanded conception of aural context that includes the technological, cultural, and phenomenal aspects of its production

Studies in ambient intelligent lighting

The revolution in lighting we are arguably experiencing is led by technical developments in the area of solid state lighting technology. The improved lifetime, efficiency and environmentally friendly raw materials make LEDs the main contender for the light source of the future. The core of the change is, however, not in the basic technology, but in the way users interact with it and the way the quality of the produced effect on the environment is judged. With the new found freedom the users can switch their focus from the confines of the technology to the expression of their needs, regardless of the details of the lighting system. Identifying the user needs, creating an effective language to communicate them to the system, and translating them to control signals that fulfill them, as well as defining the means to measure the quality of the produced result are the topic of study of a new multidisciplinary area of study, Ambient Intelligent Lighting. This thesis describes a series of studies in the field of Ambient Intelligent Lighting, divided in two parts. The first part of the thesis demonstrates how, by adopting a user centric design philosophy, the traditional control paradigms can be superseded by novel, so-called effect driven controls. Chapter 3 describes an algorithm that, using statistical methods and image processing, generates a set of colors based on a term or set of terms. The algorithm uses Internet image search engines (Google Images, Flickr) to acquire a set of images that represent a term and subsequently extracts representative colors from the set. Additionally, an estimate of the quality of the extracted set of colors is computed. Based on the algorithm, a system that automatically enriches music with lyrics based images and lighting was built and is described. Chapter 4 proposes a novel effect driven control algorithm, enabling users easy, natural and system agnostic means to create a spatial light distribution. By using an emerging technology, visible light communication, and an intuitive effect definition, a real time interactive light design system was developed. Usability studies on a virtual prototype of the system demonstrated the perceived ease of use and increased efficiency of an effect driven approach. In chapter 5, using stochastic models, natural temporal light transitions are modeled and reproduced. Based on an example video of a natural light effect, a Markov model of the transitions between colors of a single light source representing the effect is learned. The model is a compact, easy to reproduce, and as the user studies show, recognizable representation of the original light effect. The second part of the thesis studies the perceived quality of one of the unique capabilities of LEDs, chromatic temporal transitions. Using psychophysical methods, existing spatial models of human color vision were found to be unsuitable for predicting the visibility of temporal artifacts caused by the digital controls. The chapters in this part demonstrate new perceptual effects and make the first steps towards building a temporal model of human color vision. In chapter 6 the perception of smoothness of digital light transitions is studied. The studies presented demonstrate the dependence of the visibility of digital steps in a temporal transition on the frequency of change, chromaticity, intensity and direction of change of the transition. Furthermore, a clear link between the visibility of digital steps and flicker visibility is demonstrated. Finally, a new, exponential law for the dependence of the threshold speed of smooth transitions on the changing frequency is hypothesized and proven in subsequent experiments. Chapter 7 studies the discrimination and preference of different color transitions between two colors. Due to memory effects, the discrimination threshold for complete transitions was shown to be larger than the discrimination threshold for two single colors. Two linear transitions in different color spaces were shown to be significantly preferred over a set of other, curved, transitions. Chapter 8 studies chromatic and achromatic flicker visibility in the periphery. A complex change of both the absolute visibility thresholds for different frequencies, as well as the critical flicker frequency is observed. Finally, an increase in the absolute visibility thresholds caused by an addition of a mental task in central vision is demonstrated

The listening talker: A review of human and algorithmic context-induced modifications of speech

International audienceSpeech output technology is finding widespread application, including in scenarios where intelligibility might be compromised - at least for some listeners - by adverse conditions. Unlike most current algorithms, talkers continually adapt their speech patterns as a response to the immediate context of spoken communication, where the type of interlocutor and the environment are the dominant situational factors influencing speech production. Observations of talker behaviour can motivate the design of more robust speech output algorithms. Starting with a listener-oriented categorisation of possible goals for speech modification, this review article summarises the extensive set of behavioural findings related to human speech modification, identifies which factors appear to be beneficial, and goes on to examine previous computational attempts to improve intelligibility in noise. The review concludes by tabulating 46 speech modifications, many of which have yet to be perceptually or algorithmically evaluated. Consequently, the review provides a roadmap for future work in improving the robustness of speech output

Toward a synthetic acoustic ecology: sonically situated, evolutionary agent based models of the acoustic niche hypothesis

We introduce the idea of Synthetic Acoustic Ecology (SAC) as a vehicle for transdisciplinary investigation to develop methods and address open theoretical, applied and aesthetic questions in scientific and artistic disciplines of acoustic ecology. Ecoacoustics is an emerging science that investigates and interprets the ecological role of sound. It draws conceptually from, and is reinvigorating the related arts-humanities disciplines historically associated with acoustic ecology, which are concerned with sonically-mediated relationships between human beings and their environments. Both study the acoustic environment, or soundscape, as the literal and conceptual site of interaction of human and non-human organisms. However, no coherent theories exist to frame the ecological role of the soundscape, or to elucidate the evolutionary processes through which it is structured. Similarly there is a lack of appropriate computational methods to analyse the macro soundscape which hampers application in conservation. We propose that a sonically situated flavour of Alife evolutionary agent-based model could build a productive bridge between the art, science and technologies of acoustic ecological investigations to the benefit of all. As a first step, two simple models of the acoustic niche hypothesis are presented which are shown to exhibit emergence of complex spectro-temporal soundscape structures and adaptation to and recovery from noise pollution events. We discuss the potential of SAC as a lingua franca between empirical and theoretical ecoacoustics, and wider transdisciplinary research in ecoacoustic ecology

(I)MAGESOUND(S): Expanded audiovisual practice

(I)MAGESOUND(S) is a collaborative audiovisual project led by artist Jim Hobbs and composer Andrew Hill. It seeks to bring together the practices of experimental film and electroacoustic music to create live, expanded audiovisual performances. The goals of the project are to combine, share and reflect upon creative practice through the creation of expanded cinema events exploring the materiality of sound and light. To this end, here we describe two works developed as part of this project: Vientos Fuertes by Jim Hobbs and Projections by Andrew Hill

Becoming Sonic: Ambient Poetics and the Ecology of Listening in Four Militant Sound Investigations

This dissertation Becoming Sonic: Ambient Poetics and the Ecology of the Ear in Four Militant Sound Investigations offers a critical and historical analysis of acoustic ecology and soundscape recording —the sounds, noises, and silences that make up our ambient sonic environment and are found and recorded “in the field” by artists to create recordings and performances are then experienced by listeners. Field recording captures the diverse and often unwanted or inconsequential sounds of a space, which can then be used to bring attention to the often unheard and unconscious processes that stratify space. By stratification I am referring to the processes of urban planning, architecture, business, policies, and governance that shape and grid the environment. Analyzing four case studies by the sound collective Ultra-Red, sound activist Christopher DeLaurenti, and field recording artist Chris Watson, that explore the soundscapes of housing redevelopment, using a food bank, public sex in parks, and the slow violence of ecological devastation, this dissertation builds on and analyzes the sonic environmental and spatial implications of ecology by both critiquing acoustic ecology and employing it as a concept to explore the political, aesthetic, and epistemological consequences of soundscape recording. The purpose of this dissertation is to examine what sound indicates through cultural practice and how it can be used and deployed to create different understandings of the places we live and act. This research articulates a poetics of listening to space that constructs worlds and questions how the environment can be used for aesthetic purposes, how the sounds of the city and ‘nature’ influence artists, how artists practice and experience sound by listening, and what kind of knowledges these aesthetic practices produce. In order to accomplish this, it relies on critical approaches to ecology, space and urbanism (Gilles Deleuze and Fèlix Guattari, David Harvey, Nigel Thrift, and Edward Soja); ecologies of sound and listening (Steve Goodman, Murray Schafer, Susan Bickford, Frances Dyson); and affective politics (Brian Massumi, Erin Manning). This dissertation makes substantiative use of interviews, newspaper articles, and artist’s writings and statements to elucidate its investigation

Audio processing

This chapter initiates the discussion of post-production through an exploration of the ‘state of the art’ in both the practice and our theoretical understanding of audio processing, echoing the underlying pursuit the handbook stated in the introduction – that is, the bridging of dichotomies between the theoretical and the practical (the ‘how’ and the ‘why’) in/behind record production processes and outcomes. In some ways, this is also reflected in the tone and examples offered by the two authors, contributing both practice-based/phonographic illustrations, as well as surveys of relevant theorizations from other disciplines. In attempting to provide a theoretical map/ping between musical - sonic objectives, technological/processual actualization and pursued aesthetics (personal/stylistic sonic signatures in record production), we examine four domains of sonic characteristics, and ensuing tools and processes devised for their manipulation – namely ‘pitch’, ‘amplitude’, ‘spectrum and timbre’ and ‘time and space’