Towards Large Scale Evaluation of Novel Sonification Techniques for Non Visual Shape Exploration

© 2015 ACM.There are several situations in which a person with visual impairment or blindness needs to extract information from an image. Examples include everyday activities, like reading a map, as well as educational activities, like exercises to develop visuospatial skills. In this contribution we propose a set of 6 sonification techniques to recognize simple shapes on touchscreen devices. The effectiveness of these sonification techniques is evaluated though Invisible Puzzle, a mobile application that makes it possible to conduct non-supervised evaluation sessions. Invisible Puzzle adopts a gamification approach and is a preliminary step in the development of a complete game that will make it possible to conduct a large scale evaluation with hundreds or thousands of blind users. With Invisible Puzzle we conducted 131 tests with sighted subjects and 18 tests with subjects with blindness. All subjects involved in the process successfully completed the evaluation session, with high engagement, hence showing the effectiveness of the evaluation procedure. Results give interesting insights on the differences among the sonification techniques and, most importantly, show that, after a short training, subjects are able to identify many different shapes

Tac-tiles: multimodal pie charts for visually impaired users

Tac-tiles is an accessible interface that allows visually impaired users to browse graphical information using tactile and audio feedback. The system uses a graphics tablet which is augmented with a tangible overlay tile to guide user exploration. Dynamic feedback is provided by a tactile pin-array at the fingertips, and through speech/non-speech audio cues. In designing the system, we seek to preserve the affordances and metaphors of traditional, low-tech teaching media for the blind, and combine this with the benefits of a digital representation. Traditional tangible media allow rapid, non-sequential access to data, promote easy and unambiguous access to resources such as axes and gridlines, allow the use of external memory, and preserve visual conventions, thus promoting collaboration with sighted colleagues. A prototype system was evaluated with visually impaired users, and recommendations for multimodal design were derived

Developing an interactive overview for non-visual exploration of tabular numerical information

This thesis investigates the problem of obtaining overview information from complex tabular numerical data sets non-visually. Blind and visually impaired people need to access and analyse numerical data, both in education and in professional occupations. Obtaining an overview is a necessary first step in data analysis, for which current non-visual data accessibility methods offer little support. This thesis describes a new interactive parametric sonification technique called High-Density Sonification (HDS), which facilitates the process of extracting overview information from the data easily and efficiently by rendering multiple data points as single auditory events. Beyond obtaining an overview of the data, experimental studies showed that the capabilities of human auditory perception and cognition to extract meaning from HDS representations could be used to reliably estimate relative arithmetic mean values within large tabular data sets. Following a user-centred design methodology, HDS was implemented as the primary form of overview information display in a multimodal interface called TableVis. This interface supports the active process of interactive data exploration non-visually, making use of proprioception to maintain contextual information during exploration (non-visual focus+context), vibrotactile data annotations (EMA-Tactons) that can be used as external memory aids to prevent high mental workload levels, and speech synthesis to access detailed information on demand. A series of empirical studies was conducted to quantify the performance attained in the exploration of tabular data sets for overview information using TableVis. This was done by comparing HDS with the main current non-visual accessibility technique (speech synthesis), and by quantifying the effect of different sizes of data sets on user performance, which showed that HDS resulted in better performance than speech, and that this performance was not heavily dependent on the size of the data set. In addition, levels of subjective workload during exploration tasks using TableVis were investigated, resulting in the proposal of EMA-Tactons, vibrotactile annotations that the user can add to the data in order to prevent working memory saturation in the most demanding data exploration scenarios. An experimental evaluation found that EMA-Tactons significantly reduced mental workload in data exploration tasks. Thus, the work described in this thesis provides a basis for the interactive non-visual exploration of a broad range of sizes of numerical data tables by offering techniques to extract overview information quickly, performing perceptual estimations of data descriptors (relative arithmetic mean) and managing demands on mental workload through vibrotactile data annotations, while seamlessly linking with explorations at different levels of detail and preserving spatial data representation metaphors to support collaboration with sighted users

INTERACTIVE SONIFICATION STRATEGIES FOR THE MOTION AND EMOTION OF DANCE PERFORMANCES

The Immersive Interactive SOnification Platform, or iISoP for short, is a research platform for the creation of novel multimedia art, as well as exploratory research in the fields of sonification, affective computing, and gesture-based user interfaces. The goal of the iISoP’s dancer sonification system is to “sonify the motion and emotion” of a dance performance via musical auditory display. An additional goal of this dissertation is to develop and evaluate musical strategies for adding layer of emotional mappings to data sonification. The result of the series of dancer sonification design exercises led to the development of a novel musical sonification framework. The overall design process is divided into three main iterative phases: requirement gathering, prototype generation, and system evaluation. For the first phase help was provided from dancers and musicians in a participatory design fashion as domain experts in the field of non-verbal affective communication. Knowledge extraction procedures took the form of semi-structured interviews, stimuli feature evaluation, workshops, and think aloud protocols. For phase two, the expert dancers and musicians helped create test-able stimuli for prototype evaluation. In phase three, system evaluation, experts (dancers, musicians, etc.) and novice participants were recruited to provide subjective feedback from the perspectives of both performer and audience. Based on the results of the iterative design process, a novel sonification framework that translates motion and emotion data into descriptive music is proposed and described

The Ambient Horn: Designing a novel audio-based learning experience

The Ambient Horn is a novel handheld device designed to support children learning about habitat distributions and interdependencies in an outdoor woodland environment. The horn was designed to emit non-speech audio sounds representing ecological processes. Both symbolic and arbitrary mappings were used to represent the processes. The sounds are triggered in response to the children’s location in certain parts of the woodland. A main objective was to provoke children into interpreting and reflecting upon the significance of the sounds in the context in which they occur. Our study of the horn being used showed the sounds to be provocative, generating much discussion about what they signified in relation to what the children saw in the woodland. In addition, the children appropriated the horn in creative ways, trying to ‘scoop’ up new sounds as they walked in different parts of the woodland

Ground-breaking: Scientific and sonic perceptions of environmental change in the African Sahel

Soils surrounding ancient settlements can hold evidence of the activities of past societies. To seek an understanding of how past societies have reacted and contributed to environmental change requires many data sources. The real-time audiovisual installation Ground-breaking problematises the presentation of such data gained through the image-analysis of soil materials. These data are used to connote environmental events and consequent human responses. Combining these data with audiovisual synthesis and environmental recordings, a basis for developing conceptualizations of new locales undergoing environmental change is presented; the visual and sonic narratives developed allowing the art-science interface to be explored

Interactive Shape Sonification for Tumor Localization in Breast Cancer Surgery

About 20 percent of patients undergoing breast-conserving surgery require reoperation due to cancerous tissue remaining inside the breast. Breast cancer localization systems utilize auditory feedback to convey the distance between a localization probe and a small marker (seed) implanted into the breast tumor prior to surgery. However, no information on the location of the tumor margin is provided. To reduce the reoperation rate by improving the usability and accuracy of the surgical task, we developed an auditory display using shape sonification to assist with tumor margin localization. Accuracy and usability of the interactive shape sonification were determined on models of the female breast in three user studies with both breast surgeons and non-clinical participants. The comparative studies showed a significant increase in usability (p<0.05) and localization accuracy (p<0.001) of the shape sonification over the auditory feedback currently used in surgery.Comment: 15 pages, 9 figure

Here is Now and There the Sound of the Land: 'Ground-breaking'

Societies are often required to react to extreme events that arise through either anthropogenic or natural processes. Such extremity might be measured is in terms of its immediacy and intensity; it demands comprehension against understood norms. This work offers context and potential validation about change and the rate of change of an extreme environment: this is evidenced through scientific analysis of landscapes and soils and is translated, in a process of critical evaluation, to create an audio-visual installation. The installation seeks to convey cultural imprints left by societal responses to change experienced in a marginalised area, the African Sahel. By considering a landscape that is both extreme and has long-standing cultural activity, a narrative is developed

Here is now and there the sound of the land: ground-breaking

Scientific and Sonic Perceptions of the African Sahel: Societies are often required to react to extreme events that arise through either anthropogenic or natural processes. Such extremity might be measured is in terms of its immediacy and intensity; it demands comprehension against understood norms. For example, our present-day debate on future climatic change is driven by scientific assertion, reinforced by evidence gathered from both instrument and indirect proxy measurements, whilst the varying societal responses are predicated by everyday cultural experiences. In contrast, places considered to offer experiences at the boundaries of or outside the everyday, e.g. hot and cold deserts, provide a different conception of extreme. In this conception, change and the rates of change typically lack context, validation and position within everyday norms. Consequently, it is within such surroundings that the greatest tension occurs between the perception of place and rates of change. While the methodologies of science and art practice are often respectively considered positivistic and non-rational, both are in fact able to investigate the extreme in this context. Whether or not such characterisations are legitimate, the obvious epistemological differences both illuminate and problematise our understanding. In this paper we describe a real-time generative installation commissioned from the authors by the UK Research Councils called Ground-breaking: Extreme Landscapes in Grains and Pixels that attempts to explore and test these differences. Further examples are available at http://www.ground-breaking.net