It can be difficult to guide yourself across a crosswalk when your visual capabilities are limited, which can be an everyday issue for someone with impaired vision. This paper aims to alleviate that issue for zebra stripe crosswalks by proposing an algorithm that incorporates multiple properties of zebra stripe crosswalks with a neural network to assist in quickly and accurately identifying a crosswalk in video and pictures taken from a smartphone camera. This method improves the accuracy of zebra crosswalk detection in images. In a large dataset, it correctly identified 76.5% of zebra crosswalks, while reducing the false discovery rate (q-value) from 20% without using neural networks to 2.21% using this neural network method. Only 2.04% of non-crosswalk images as crosswalks using the neural network method.

The most common navigation aid visually-impaired people employ is a white cane, but, recently, technology has given rise to a varied set of sophisticated navigation aids. While these new aids can provide more assistance to a visually-impaired person than a white cane, they tend to be expensive due to a small market segment, which in turn can reduce their accessibility. In an effort to produce a technologically-advanced yet accessible navigation aid, an Android application is proposed that detects and notifies users about obstacles within their path through the use of a smartphone's camera. While the smartphone is mounted on a harness worn by the user, the Walking Assistant application operates by capturing images as the user walks, finding features of objects within each frame, and determining how the features have moved from image to image. If it is discovered that an object is moving towards the user, the Walking Assistant will activate the smartphone's vibration mode to alert the user to the object's presence. Additionally, the user can control the Walking Assistant through the use of either touch or voice commands. By conducting real-world tests, it was determined that the Walking Assistant can correctly identify obstacles 42.1% of the time, while generating false positive obstacle identifications only 15.0% of the time. The accuracy of the Walking Assistant can be further improved by implementing additional features, such as a fuzzy-decision-based thresholding system or image stabilization.

The growth of web-based malware and phishing attacks has catalyzed significant advances in the research and use of interstitial warning pages and modals by a browser prior to loading the content of a suspect site. These warnings commonly use visual cues to attract users' attention, including specialized iconography, color, and an absence of buttons to communicate the importance of the scenario. While the efficacy of visual techniques has improved safety for sighted users, these techniques are unsuitable for blind and visually impaired users. This is likely not due to a lack of interest or technical capability by browser manufactures, where universal design is a core tenet of their engineering practices, but instead a reflection of the very real dearth of research literature to inform best practices, exacerbated by a deficit of clear methodologies for conducting studies with this population. Indeed, the challenges are manifold. In this paper, we present the results of our study analyzing the experiences of the visually impaired with browser security warnings, detail the development and advancement of the methodological best practices when conducting a study of this kind, and ultimately identify some initial approaches that could improve the security for this population.

Sight is essential in our daily tasks. Compensatory senses have been used for centuries by visually impaired individuals to navigate independently. The help of technology can minimize some challenges for visually impaired individuals. Assistive navigation technologies facilitate the pathfinding and tracing in indoor scenarios. Different modules are added to assistive navigation technologies to warn about the obstacles not only on the ground but about hanging objects. In this work, we attempt to explore new methods to assist visually impaired individuals in navigating independently in an indoor scenario. We employed a location estimation algorithm based on the fingerprinting method to estimate the initial location of the user. We mitigate the error of estimation with particle filter. The shortest path has been calculated with an A* algorithm. To provide the user with an accident-free experiment, we employed an obstacle avoidance algorithm capable of warning the users about the potential hazards. Finally, to provide an effective means of communication with the user, we employed text-to-speech and speech recognition algorithms. The main contribution of this work is to glue these modules together efficiently and affordably.

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This paper presents findings from a study designed to identify skills and strategies students with visual impairments have developed to aid their social integration into higher education campus life. Attending college provides numerous learning opportunities outside the classroom. The study explores the process by which students at two universities in the Commonwealth of Virginia were able to identify, navigate, and participate in extra-curricular activities. Previous research by Roy & MacKay (2002) and Hodges & Keller (1999) provides a quantitative framework from which a qualitative tapestry was woven. A secondary purpose of the study was to verify the validity of Roy & MacKay's finding that the age that individuals first experience visual disability and the visibility of their visual impairment (the variance in their ability to appear sighted) are valid predictors of social integration of visually impaired students among college students. This study is important for several reasons, including, (a) to help develop a more inclusive campus environment, (b) to identify factors that have influenced the selection of post-secondary educational experiences by visually-impaired students, and (c) to give a voice to visually impaired students to help administrators understand their needs and desires (Henderson, 2001). / Ph. D.

Thesis advisor: Josh Seim / In this thesis, I examine the productivity of emulation experiences as they relate to building empathy for systems of oppression by utilizing Dinner in the Dark, a vision impairment simulation dinner, hosted by the Boston College Undergraduate Government of Boston College Council for Students with Disabilities, as a case study. Drawing from semi-structured qualitative interviews with 19 participants of Dinner in the Dark and field notes taken on site of both nights of the dinner, I find that developing empathy or experiencing an increase in empathy following Dinner in the Dark did not always necessarily translate into an inclusive and non-stereotypical understanding of the visually impaired disabled identity. In other words, although simulation may promote empathy, emulating a state of being that one is not naturally in possession of, especially if it is also for a brief period, may provide misleading information as well as prompt discrimination. / Thesis (BA) — Boston College, 2024. / Submitted to: Boston College. Morrissey School of Arts and Sciences. / Discipline: Sociology. / Discipline: Departmental Honors.

No / This paper describes a set of experiments that investigated the use of rising pitch notes to communicate graphical information to visually impaired users. The information communicated in the experiments included coordinate locations within a 40×40 graphical grid, the navigation of an auditory cursor within the graphical grid, the communication of simple graphical shapes and their size. The five simple shapes communicated were rectangles, squares, circles, horizontal and vertical lines. Stereophony, timbre, rhythms, and short tunes were used in addition to the rising pitch metaphor to aid disambiguation. Results suggested that the rising pitch approach enabled visually impaired users to understand the graphical information communicated in the absence of any visual aid. The paper concludes with a discussion of the use of rising pitch metaphor to communicate graphical information.

Image sizes have increased exponentially in recent years. The resulting high-resolution images are typically encoded in a lossy fashion to achieve high compression ratios. Lossy compression can be categorized into visually lossless and visually lossy compression depending on the visibility of compression artifacts. This dissertation proposes visually lossless coding methods as well as a visually lossy coding method with perceptual quality control. All resulting codestreams are JPEG2000 Part-I compliant.Visually lossless coding is increasingly considered as an alternative to numerically lossless coding. In order to hide compression artifacts caused by quantization, visibility thresholds (VTs) are measured and used for quantization of subbands in JPEG2000. In this work, VTs are experimentally determined from statistically modeled quantization distortion, which is based on the distribution of wavelet coefficients and the dead-zone quantizer of JPEG2000. The resulting VTs are adjusted for locally changing background through a visual masking model, and then used to determine the minimum number of coding passes to be included in a codestream for visually lossless quality under desired viewing conditions. The proposed coding scheme successfully yields visually lossless images at competitive bitrates compared to those of numerically lossless coding and visually lossless algorithms in the literature.This dissertation also investigates changes in VTs as a function of display resolution and proposes a method which effectively incorporates multiple VTs for various display resolutions into the JPEG2000 framework. The proposed coding method allows for visually lossless decoding at resolutions natively supported by the wavelet transform as well as arbitrary intermediate resolutions, using only a fraction of the full-resolution codestream. When images are browsed remotely, this method can significantly reduce bandwidth usage.Contrary to images encoded in the visually lossless manner, highly compressed images inevitably have visible compression artifacts. To minimize these artifacts, many compression algorithms exploit the varying sensitivity of the human visual system (HVS) to different frequencies, which is typically obtained at the near-threshold level where distortion is just noticeable. However, it is unclear that the same frequency sensitivity applies at the supra-threshold level where distortion is highly visible. In this dissertation, the sensitivity of the HVS for several supra-threshold distortion levels is measured based on the JPEG2000 quantization distortion model. Then, a low-complexity JPEG2000 encoder using the measured sensitivity is described. The proposed visually lossy encoder significantly reduces encoding time while maintaining superior visual quality compared with conventional JPEG2000 encoders.

The purpose of this study was to describe the prevalence of self-reported visual and neck/shoulder complaints among individuals with a low vision diagnosis. The study also aimed to examine whether there was an association between the degree of self-rated visual and the neck/shoulder complaints. There was a questionnaire survey that was conducted on patients that visits an eye center in a county in central Sweden. There were a total of 18 people participated in the survey, between 17-92 years old. The questionnaire contained 22 questions and was analyzed with SPSS. The results showed how the distributions of answers were to the questions about the respondents’ vision respectively of respondents’ musculoskeletal problems. Results also showed that there was an association between the degree of self- rated visual difficulties and the degree of self- rated neck/shoulder disorder. The results in this study support the hypothesis that a relationship exists between visual and musculoskeletal problems. / Syftet med denna studie varatt beskriva förekomsten av självskattade syn och nacke/skuldra besvär hospersoner med ögonsjukdomar. Studien syftade också till att undersöka om det fannsett samband mellan graden av självskattade synbesvär och självskattade besvär inacke/skuldra. Enkätundersökning genomfördes på patienter som besökte ensyncentral i ett län i mellersta Sverige. Totalt 18 personer deltog iundersökningen, inom ålderskategorin 17-92 år gamla. Enkäten innehöll 22 frågorinklusive bakgrundsfrågor om kön och livsfaktorer som sedan analyserades medhjälp av databasen SPSS. Resultaten visade hur fördelningarna av svaren påfrågorna om respondenternas syn respektive muskuloskeletala problem. Resultatetvisade också att det fanns ett statistiskt signifikant samband mellan graden avsjälvbeskattade synbesvär och graden av självbeskattade nacke/skuldra besvär.Resultaten ger stöd för hypotesen att det finns en relation mellan öga-nacke/skuldrabesvär hos synsvaga individer.