Design For Auditory Displays: Identifying Temporal And Spatial Information Conveyance Principles

Designing auditory interfaces is a challenge for current human-systems developers. This is largely due to a lack of theoretical guidance for directing how best to use sounds in today\u27s visually-rich graphical user interfaces. This dissertation provided a framework for guiding the design of audio interfaces to enhance human-systems performance. This doctoral research involved reviewing the literature on conveying temporal and spatial information using audio, using this knowledge to build three theoretical models to aid the design of auditory interfaces, and empirically validating select components of the models. The three models included an audio integration model that outlines an end-to-end process for adding sounds to interactive interfaces, a temporal audio model that provides a framework for guiding the timing for integration of these sounds to meet human performance objectives, and a spatial audio model that provides a framework for adding spatialization cues to interface sounds. Each model is coupled with a set of design guidelines theorized from the literature, thus combined, the developed models put forward a structured process for integrating sounds in interactive interfaces. The developed models were subjected to a three phase validation process that included review by Subject Matter Experts (SMEs) to assess the face validity of the developed models and two empirical studies. For the SME review, which assessed the utility of the developed models and identified opportunities for improvement, a panel of three audio experts was selected to respond to a Strengths, Weaknesses, Opportunities, and Threats (SWOT) validation questionnaire. Based on the SWOT analysis, the main strengths of the models included that they provide a systematic approach to auditory display design and that they integrate a wide variety of knowledge sources in a concise manner. The main weaknesses of the models included the lack of a structured process for amending the models with new principles, some branches were not considered parallel or completely distinct, and lack of guidance on selecting interface sounds. The main opportunity identified by the experts was the ability of the models to provide a seminal body of knowledge that can be used for building and validating auditory display designs. The main threats identified by the experts were that users may not know where to start and end with each model, the models may not provide comprehensive coverage of all uses of auditory displays, and the models may act as a restrictive influence on designers or they may be used inappropriately. Based on the SWOT analysis results, several changes were made to the models prior to the empirical studies. Two empirical evaluation studies were conducted to test the theorized design principles derived from the revised models. The first study focused on assessing the utility of audio cues to train a temporal pacing task and the second study combined both temporal (i.e., pace) and spatial audio information, with a focus on examining integration issues. In the pace study, there were four different auditory conditions used for training pace: 1) a metronome, 2) non-spatial auditory earcons, 3) a spatialized auditory earcon, and 4) no audio cues for pace training. Sixty-eight people participated in the study. A pre- post between subjects experimental design was used, with eight training trials. The measure used for assessing pace performance was the average deviation from a predetermined desired pace. The results demonstrated that a metronome was not effective in training participants to maintain a desired pace, while, spatial and non-spatial earcons were effective strategies for pace training. Moreover, an examination of post-training performance as compared to pre-training suggested some transfer of learning. Design guidelines were extracted for integrating auditory cues for pace training tasks in virtual environments. In the second empirical study, combined temporal (pacing) and spatial (location of entities within the environment) information were presented. There were three different spatialization conditions used: 1) high fidelity using subjective selection of a best-fit head related transfer function, 2) low fidelity using a generalized head-related transfer function, and 3) no spatialization. A pre- post between subjects experimental design was used, with eight training trials. The performance measures were average deviation from desired pace and time and accuracy to complete the task. The results of the second study demonstrated that temporal, non-spatial auditory cues were effective in influencing pace while other cues were present. On the other hand, spatialized auditory cues did not result in significantly faster task completion. Based on these results, a set of design guidelines was proposed that can be used to direct the integration of spatial and temporal auditory cues for supporting training tasks in virtual environments. Taken together, the developed models and the associated guidelines provided a theoretical foundation from which to direct user-centered design of auditory interfaces

Audiophysic simulation library for video games [NoPhysicsLibrary]

Nowadays, sound designers must hard-code any acoustic effect in their video game, because there is not any module that automatizes the real audio behavior depending on the physical environment. That is what NoPhysicsLibrary is: a C++ library that allows developers to create their own world, apply realistic physics to it, and play sfx that change depending on the environment. The report shows a detailed description of the physics module, which explains the iteration methods and integration calculations. Also, is included a detailed explanation of the formulas used to calculate the real-time effects that will be applied to the played audio files, such as spatialization, volume attenuation, sound occlusion, frequential attenuation, pitch variation, and time delay. Finally, an overview of the audio system's functionality is presented. The resulting library is published on a github repository and several stand-alone test scenarios are provided. Two demonstration videos are also presented as part of this work, featuring all the acoustic effects covered by NoPhysicsLibrary

Concurrent speech feedback for blind people on touchscreens

Tese de Mestrado, Engenharia Informática, 2023, Universidade de Lisboa, Faculdade de CiênciasSmartphone interactions are demanding. Most smartphones come with limited physical buttons, so users can not rely on touch to guide them. Smartphones come with built-in accessibility mechanisms, for example, screen readers, that make the interaction accessible for blind users. However, some tasks are still inefficient or cumbersome. Namely, when scanning through a document, users are limited by the single sequential audio channel provided by screen readers. Or when tasks are interrupted in the presence of other actions. In this work, we explored alternatives to optimize smartphone interaction by blind people by leveraging simultaneous audio feedback with different configurations, such as different voices and spatialization. We researched 5 scenarios: Task interruption, where we use concurrent speech to reproduce a notification without interrupting the current task; Faster information consumption, where we leverage concurrent speech to announce up to 4 different contents simultaneously; Text properties, where the textual formatting is announced; The map scenario, where spatialization provides feedback on how close or distant a user is from a particular location; And smartphone interactions scenario, where there is a corresponding sound for each gesture, and instead of reading the screen elements (e.g., button), a corresponding sound is played. We conducted a study with 10 blind participants whose smartphone usage experience ranges from novice to expert. During the study, we asked participants’ perceptions and preferences for each scenario, what could be improved, and in what situations these extra capabilities are valuable to them. Our results suggest that these extra capabilities we presented are helpful for users, especially if these can be turned on and off according to the user’s needs and situation. Moreover, we find that using concurrent speech works best when announcing short messages to the user while listening to longer content and not so much to have lengthy content announced simultaneously

An audio architecture integrating sound and live voice for virtual environments

The purpose behind this thesis was to design and implement audio system architecture, both in hardware and in software, for use in virtual environments. The hardware and software design requirements were to provide the ability to add sounds, environmental effects such as reverberation and occlusion, and live streaming voice to any virtual environment employing this architecture. Several free or open-source sound APIs were evaluated, and DirectSound3D was selected as the core component of the audio architecture. Creative Labs Environmental Audio Extensions (EAX) was integrated into the architecture to provide environmental effects such as reverberation, occlusion, obstruction, and exclusion. Voice over IP (VoIP) technology was evaluated to provide live, streaming voice to any virtual environment. DirectVoice was selected as the voice component of the architecture due to its integration with DirectSound3D . However, extremely high latency considerations with DirectVoice, and any other VoIP application or software, required further research into alternative live voice architectures for inclusion in virtual environments. Ausim3D's GoldServe Audio Localizing Audio Server System was evaluated and integrated into the hardware component of the audio architecture to provide an extremely low-latency, live, streaming voice capability.http://archive.org/details/anudiorchitectur109454977Commander, United States Naval ReserveApproved for public release; distribution is unlimited