Ludovico Antonio Muratori

Monitoring accessibility: large scale evaluations at a Geo political level

Once we assumed that Web accessibility is a right, we implicitly state the necessity of a governance of it. Beyond any regulation, institutions must provide themselves with suitable tools to control and support accessibility on typically large scale scenarios of content and resources. No doubt, the economic impact and effectiveness of these tools affect accessibility level. In this paper, we propose an application to effectively monitor Web accessibility from a geo-political point of view, by referring resources to the specific (category of) institutions which are in charge of it and to the geographical places they are addressed to. Snapshots of such a macro level spatial-geo-political analysis can be used to effectively focus investments and skills where they are actually necessary.

Metrics for accessibility on the Vamolà project

How far are the Web sites from accessibility? Such a question implies a measure and, before, metrics or a set of metrics to quantitatively describe distances or closeness to one or more aspects of inclusion. Quantitative evaluations can effectively guide the improvement of sites quality and of skills which are necessary along the content authoring process. This paper details the hypothesized metrics and measures on the Vamolà project, which has been issued to integrate a monitor and a validator of the Web accessibility, according to the Italian Law. On Vamolà, the validation tool output can be effectively used in defining metrics inside the monitor application.

Cooperative multimedia management for participative learning: A case study

Web 2.0 has definitively twisted roles and rules within processes leading to the final online resources we all can enjoy on the Internet. Producers and consumers of Web contents merged into “prosumers”, dialectically sharing their knowledge, their experiences, as well as their needs. Such novel dynamics provide a strong spin-off for e-learning methodologies and technologies, by allowing students participation along learning materials life cycle, from simple feedbacks, up to real enrichments of didactical resources. As elsewhere on the Web 2.0 scenario, inclusive aspects of e-learning 2.0 represent either a new challenge or a new opportunity. This paper presents an e-learning 2.0 tool which is able to support users during the collaborative editing of didactical contents, from simple text to compound multimedia. Starting from a resource provided by the lecturer, learners can contribute in adding alternative contents and views, creating a multidimensional information structure. The resulting enriched material can be tailored to a specific user by resorting to automatic adaptation mechanisms. By utilizing typical Web 2.0 interfaces, our system involves all the different actors (lecturers, learning technologists, student support services, staff developers and students) to play a key role in improving the accessibility and, more generally, the effectiveness of learning materials.

Automatically producing IMS AccessForAll Metadata

Accessible e-learning is becoming a key issue in ensuring a complete inclusion of people with disabilities within the knowledge society. Many efforts have been done to include accessibility information in e-learning metadata and the major result consists in the IMS AccessForAll Metadata definition. Unfortunately the complex behavior managed by this standard could be perceived by authors as a new boring and difficult activity enforcing the idea that the production of accessible Learning Objects (LOs) is too complex to be accomplished. This paper presents a novel component of an authoring and producing software architecture, designed and implemented to automatically create the IMS AccessForAll Metadata description of an accessible LO.

GAPforAPE: an augmented browsing system to improve Web 2.0 accessibility

The Web 2.0 evolution has spread more interactive technologies which affected accessibility for users who navigate the Web by using assistive technologies. In particular, the partial download of new data, the continuous refreshing, and the massive use of scripting can represent significant barriers especially for people with visual impairments, who enjoy the Web by means of screen readers. On the other hand, such technologies can be an opportunity, because they can provide a new means of transcoding Web content, making the Web more accessible. In this article we present GAPforAPE, an augmented browsing system (based on Web browsers extensions) which offers a users profiling system and transcodes Web content according to constrains declared by users: the same Web page is provided to any user, but GAPforAPE computes adequate customizations, by exploiting scripting technologies which usually affect Web pages accessibility. GAPforAPE imitates screen readers behavior: it applies a specific set of transcoding scripts devoted to a given Web site, when available, and a default set of transcoding operations otherwise. The continuous and quick evolution of the Web has shown that a crowdsourcing system is a desirable solution, letting the transcoding scripts evolve in the same way.

At the Crossroads of Web and Interactive Multimedia: An Approach to Merge the Two Realms

Multimedia and Web 2.0 can meet up. Despite the success they have obtained in last years, these two domains present some important limitations. In particular, current Web 2.0 based technologies, such as wikis, blogs, podcasts, commonly resort to sequential combinations of contents, rather than exploiting dynamic and synchronized compositions of discrete and continuous media resources. On the other hand, tools for multimedia content authoring and distribution usually lack cooperativeness, interactivity, use of adequate metatagging structures and application mash-up. This paper discusses how by merging these two worlds it is possible to inherit the advantages while removing their limitations. We describe a system exemplar we developed for the cooperative creation, manipulation and sharing of rich media contents.

Integrating manual and automatic evaluations to measure accessibility barriers

Explicit syntax and implicit semantics of Web coding are typically addressed as distinct dominions in providing metrics for content accessibility. A more down-to-earth portrait about barriers and their impact on users with disa-bilities could be obtained whether any quantitative synthesis about number and size of barriers integrated measurements from automatic checks and human as-sessments. In this work, we present a metric to evaluate accessibility as a unique meas-ure of both syntax correctness and semantic consistence, according to some general assumptions about relationship and dependencies between them. WCAG 2.0 guidelines are used to define boundaries for any single barrier eval-uation, either from a syntactic point of view, or a subjective/human one. In or-der to assess our metric, gathered data form a large scale accessibility monitor has been utilized.

The Directors' cut: a solution to collaborative multimedia management

Web 2.0 applications allow rich media contents to be exposed and shared by users. Nevertheless, usually, a multimedia is provided as an unicum, made by synchronized media items. Sound tracks, video sequences, captions, cannot be customized “on-the-fly” by users. Managing multimedia in a deep way would meet the expectations of nowadays Web prosumers (i.e. producers and consumers), and it would widen the audience. Describing and synchronizing each medium, as well as specifying different alternative contents for it, are the keystones of multimedia customization and of audience widening. This paper presents a multimedia collaborative system, which provides support to the arrangement of medium into a multi-views composed multimedia. Each prosumer can add medium by juxtaposition or by defining it as an alternative (audio, video, textual) version of an existing one. The implementation of such a system is based on SMIL 3.0 specification but implements a new and compact syntax to let users manipulate the original multimedia synchronization and their alternatives. The proposed approach has been put to test in two different scenarios.

Avoiding to dispense with accuracy: a method to make different DTDs documents comparable

The Italian regulations about Web content accessibility impose HTML 4.01 strict, XHTML 1.0 strict or superior grammar validity. Such markup constraints are complied by a low percentage of Public Institution sites. In order to include the largest amount of not strict DTD sites on a synthetic, realistic representation of accessibility degree, this paper presents an experimental approach to set up parameters for making validity measures uniform, despite they are taken from evaluating different grammars. The proposed method allows for effectiveness in computing and storing information which otherwise will be quite unfeasible. Finally, the generalization of such an approach is shown to be suited for markup quality evaluations, beyond explicit law requirements.

Hacking Nintendo Wii to paint virtual graffiti

Any approach to the issues of virtual reality implies a general question about how to effectively plunge inside it. Despite a great variety of settings, the more feedbacks are the same as real ones, the more users feel involved on a likely situation. We can split such an assumption into the necessity of effective gestural recognition and likelihood of virtual tools to reality. In this paper we will present a system to draw virtual graffiti on the PC screen, as it were a wall. A virtual, but tangible aerosol bomb has been designed and built, by exploiting the Nintendo console gaming device and sensor system. Our object has the same shape and the same way of use as a common, real spray paint dispenser and it can be used on quite every available graphics application on a Desktop or notebook case. Besides the advantages due to the low costs and the good accuracy of gesture recognition, our system confirms the importance of similarity in simulated scenarios.