Transcoding for web accessibility for the blind : semantics from structure

True accessibility requires minimizing the scanning time to find a particular piece of information. Sequentially reading web pages do not provide this type of accessibility, for instance before the user gets to the actual text content of the page it has to go through a lot of menus and headers. However if the user could navigate a web page based through semantically classified blocks then the user could jump faster to the actual content of the page, skipping all the menus and other parts of the page. We propose a transcoding engine that tackles accessibility at two distinct, yet complementary, levels: for specific known sites and general unknown sites. We present a tool for building customized scripts for known sites that turns this process in an extremely simple task, which can be performed by anyone, without any expertise. For general unknown sites, our approach relies on statistical analysis of the structural blocks that define a web page to infer a semantic for the block.(undefined

Creating a user-specific environment : the author implications

Our empirical survey shows that users with visual impairments find the sheer volume of information in typical web pages to be overwhelming and therefore sometimes refrain from using the web. By developing the concept and use of the Essentiality and Proficiency Tool we allow the user to personalise the content they view with the level of essentiality specified by both the author and the user. Hence in this paper we explore one method of rating essentiality and the application of the essentiality levels to web content. The author is given the task of ensuring that the most essential content is relayed to the user given the user's preferences for volume. We present one such example of the author rating the content and the implications. The tool allows the user to personalise content based upon how much information is required or acceptable, by selecting a band of 'essentialities', the user's 'proficiency'. This is then matched with how ‘essential’ the designer feels are various areas of the content. Together this collaborative importance rating determines the presentation of the content. Hence the importance of this tool lies in the collaboration of the essentiality level set by both the author and the user, resulting in just the right amount of content (determined by the user) conveying just the right amount of detail (determined by the author)

Scaffolding Visually Cluttered Web Pages to Facilitate Accessibility

Increasingly, rich and dynamic content and abundant links are making Web pages visually cluttered and widening the accessibility divide for the disabled and people with impairments. The adaptations approach of transforming Web pages has enabled users with diverse abilities to access a Web page. However, the challenge remains for these users to work with a Web page, particularly among people with minimal Web experience and cognitive limitations. We propose that scaffolding can allow users to learn certain skills that help them function online with greater autonomy. In the case of visually cluttered Web pages, several accessibility scaffoldings were created to enable users to learn where core content begins, how text flows in a part of a Web page, and what the overall structure of a Web page is. These scaffoldings expose the elements, pathways, and organization of a Web page that enable users to interpret and grasp the structure of a Web page. We present the concept of an accessibility scaffolding, the designs of the scaffoldings for visually cluttered pages, and user feedback from people who work with our target end-users

Using an essentiality and proficiency approach to improve the web browsing experience of visually impaired users

Increased volumes of content exacerbate the Web accessibility issues faced by people with visual impairments. Essentiality & Proficiency is presented as one method of easing access to information in Websites by addressing the volume of content coupled with how it is presented. This research develops the concept of Essentiality for Web authors. A preliminary survey was conducted to understand the accessibility issues faced by people with visual impairments. Structured interviews were conducted with twelve participants and a further 26 participants responded to online questionnaires. In total there were 38 participants (both sexes), aged 18 to 54 years. 68% had visual impairments, three had motor issues, one had a hearing impairment and two had cognitive impairments. The findings show that the overload of information on a page was the most prominent difficulty experienced when using the Web. The findings from the preliminary survey fed into an empirical study. Four participants aged 21 to 54 years (both sexes) from the preliminary survey were presented with a technology demonstrator to check the feasibility of Essentiality & Proficiency in the real environment. It was found that participants were able to identify and appreciate the reduced volume of information. This initiated the iterative development of the prototype tool. Microformatting is used in the development of the Essentiality & Proficiency prototype tool to allow the reformulated Web pages to remain standards compliant. There is a formative evaluation of the prototype tool using an experimental design methodology. A convenience sample of nine participants (both sexes) with a range of visual impairments, aged 18 to 52 performed tasks on a computer under three essentiality conditions. With an alpha level .05, the evaluation of the Essentiality & Proficiency tool has been shown to offer some improvement in accessing information

Using an essentiality & proficiency approach to improve the web browsing experience of visually impaired users

Increased volumes of content exacerbate the Web accessibility issues faced by people with visual impairments. Essentiality & Proficiency is presented as one method of easing access to information in Websites by addressing the volume of content coupled with how it is presented. This research develops the concept of Essentiality for Web authors. A preliminary survey was conducted to understand the accessibility issues faced by people with visual impairments. Structured interviews were conducted with twelve participants and a further 26 participants responded to online questionnaires. In total there were 38 participants (both sexes), aged 18 to 54 years. 68% had visual impairments, three had motor issues, one had a hearing impairment and two had cognitive impairments. The findings show that the overload of information on a page was the most prominent difficulty experienced when using the Web. The findings from the preliminary survey fed into an empirical study. Four participants aged 21 to 54 years (both sexes) from the preliminary survey were presented with a technology demonstrator to check the feasibility of Essentiality & Proficiency in the real environment. It was found that participants were able to identify and appreciate the reduced volume of information. This initiated the iterative development of the prototype tool. Microformatting is used in the development of the Essentiality & Proficiency prototype tool to allow the reformulated Web pages to remain standards compliant. There is a formative evaluation of the prototype tool using an experimental design methodology. A convenience sample of nine participants (both sexes) with a range of visual impairments, aged 18 to 52 performed tasks on a computer under three essentiality conditions. With an alpha level .05, the evaluation of the Essentiality & Proficiency tool has been shown to offer some improvement in accessing information.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Using an essentiality & proficiency approach to improve the web browsing experience of visually impaired users

Increased volumes of content exacerbate the Web accessibility issues faced by people with visual impairments. Essentiality & Proficiency is presented as one method of easing access to information in Websites by addressing the volume of content coupled with how it is presented. This research develops the concept of Essentiality for Web authors. A preliminary survey was conducted to understand the accessibility issues faced by people with visual impairments. Structured interviews were conducted with twelve participants and a further 26 participants responded to online questionnaires. In total there were 38 participants (both sexes), aged 18 to 54 years. 68% had visual impairments, three had motor issues, one had a hearing impairment and two had cognitive impairments. The findings show that the overload of information on a page was the most prominent difficulty experienced when using the Web. The findings from the preliminary survey fed into an empirical study. Four participants aged 21 to 54 years (both sexes) from the preliminary survey were presented with a technology demonstrator to check the feasibility of Essentiality & Proficiency in the real environment. It was found that participants were able to identify and appreciate the reduced volume of information. This initiated the iterative development of the prototype tool. Microformatting is used in the development of the Essentiality & Proficiency prototype tool to allow the reformulated Web pages to remain standards compliant. There is a formative evaluation of the prototype tool using an experimental design methodology. A convenience sample of nine participants (both sexes) with a range of visual impairments, aged 18 to 52 performed tasks on a computer under three essentiality conditions. With an alpha level .05, the evaluation of the Essentiality & Proficiency tool has been shown to offer some improvement in accessing information.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Computer Vision on Web Pages: A Study of Man-Made Images

This thesis is focused on the development of computer vision techniques for parsing web pages using an image of the rendered page as evidence, and on understanding this under-explored class of images from the perspective of computer vision. This project is divided into two tracks---applied and theoretical---which complement each other. Our practical motivation is the application of improved web page parsing to assistive technology, such as screenreaders for visually impaired users or the ability to declutter the presentation of a web page for those with cognitive deficit. From a more theoretical standpoint, images of rendered web pages have interesting properties from a computer vision perspective; in particular, low-level assumptions can be made in this domain, but the most important cues are often subtle and can be highly non-local. The parsing system developed in this thesis is a principled Bayesian segmentation-classification pipeline, using innovative techniques to produce valuable results in this challenging domain. The thesis includes both implementation and evaluation solutions. Segmentation of a web page is the problem of dividing it into semantically significant, visually coherent regions. We use a hierarchical segmentation method based on the detection of semantically significant lines (possibly broken lines) which divide regions. The Bayesian design allows sophisticated probability models to be applied to the segmentation process, and our method produces segmentation trees that achieve good performance on a variety of measures. Classification, for our purposes, is identifying the semantic role of regions in the segmentation tree of a page. We achieve promising results with a Bayesian classification algorithm based on the novel use of a hidden Markov tree model, in which the structure of the model is adapted to reflect the structure of the segmentation tree. This allows the algorithm to make effective use of the context in which regions appear as well as the features of each individual region. The methods used to evaluate our page parsing system include qualitative and quantitative evaluation of algorithm performance (using manually-prepared ground truth data) as well as a user study of an assistive interface based on our page segmentation algorithm. We also performed a separate user study to investigate users' perceptions of web page organization and to generate ground truth segmentations, leading to important insights about consistency. Taken as a whole, this thesis presents innovative work in computer vision which contributes both to addressing the problem of web accessibility and to the understanding of semantic cues in images