Animation n Animated GIF n Javascript n Java

Animation n Animated GIF n Javascript n Java n Vector animation: Flash, SVG n Shockwave n 3 D

Raster vs Vector n Vector: items drawn with lines n Smooth n Scaled very well n Cannot be filled with multiple colors n Raster: pixel based n 3 D shading

Raster vs. Vector Raster

Raster vs. Vector

Informing the User n Provide information to user n Inform of potential load/play times n Required plugins

Multimedia Information

3 D for the Web n Use of 3 D very limited (still) n Commonly used for product views n Very computational intensive n VRML n Shockwave

Web 3 D Formats

Controls

3 D and Performance 3 D files require: n Large amounts of memory n Large amounts of bandwidth

Level of Detail

Successive Refinement

Mpeg-4 n Future standard: Combines: n Audio n Video n Vector Graphics n 3 D Graphics

MPEG-4

Human Representation n Means to represent virtual humans n Called avatars n Used to interact with user Typically used in online games representing: n Other users n Non-player charactures

HANIM

Poser

Accessibility n Web should be usable by everyone This includes users with: n Vision impairments n Hearing impairments n Mobility impairments

Statistics n 8 million people with visual impairments n 20 million deaf or hard-of hearing n 250, 000 with spinal cord injuries n 500, 000 with cerebral palsy n 330, 000 with MS n More that half US population over 65 has some type of impairment

Issues involving Vision n Web very visually oriented n Significant challenges n Severity ranges from total blindness to low vision n Color blindness n Visual Stimuli

Information Delivery n Information display on traditional monitor not available to users with visual impairments Two assistive technologies: n Screen Readers n Refreshable Braille displays

Screen readers Reads text component of web screen Includes: n Links n Menus n Dialog Boxes n Error Messages

Screen Readers n Several vendors offer screen readers n Prices range from $300 to $1000 n Page must be reformatted to support screen readers n HTML “lang” attribute controls language page will be read in

Refreshable Braille Display n For people who are deaf as well as blind screen readers do not work. n Translates text of page into Braille n Single line of Braille text n Prices range from $4500 to $14, 500

Grade II Braille

Refreshable Braille Display

Reformatting Text n For screen readers to work text of page must be formatted to support linear delivery n Tabular data n Label for Elements n Skip navigation n Alt Tags for images

Tabular Data

Course Course Markup Strategy for Tables

Skip Navigation

Normal Page

Alt Tags (None)

Alt Tags (Descriptive)

Other Vision Issues n Screen Magnifiers n Color Blindness: – 8% male population – 0. 5% Female population – Most common red/green n Photo Sensitive Epilepsy

Color Blindness This is an Ishihara plate commonly used to check for red/green color blindness

Color Blindness This is what a red/green color-blind person might see. Note that the digit (3) is practically invisible.

Mobility Impairments n Conditions with affect use of keyboard and mouse n Might be difficult, Might be impossible n Predictive typing n Speech recognition n Alternative input technology

Hearing Impairments Few more issues: n Captioned media n Open or Closed captioning n American Sign Language

Web Accessibility Initiative n Promote usability for people with disabilities n Goal of Universal Access n Set of guidelines which address 2 themes: – Graceful Translation – Make content understandable and navigable

Web Accessibility Initiative Guidelines

Globalization n Web is growing all over world n Number of Non English speaking users rapidly increasing n Usability issues involve use of language and culture n This processes is called globalization

Global User Population

Internationalization n Internationalization single design used world wide n Simpler text n Unambiguous display of number, currency, dates, and times n Isolate and remove culturally specific language

Localization n Added cultural context n Translation of web page into local language n Relevant content

Text and Translation n Translation: human or automatic? n Attention to writing style n Expression of dates, times n Express currency in local terms n Label units of measurements

Languages Can Expand Labels

Page Layout n Unicode for character support n Color issues n Icon issues (including flags) n Text Alignment (left vs. right)

International User Testing n International and local sites need user testing n More involved than traditional n Test success of translation n International Inspection as alternative n Difficulties dues to language gap

Personalization n Strategy for gaining competitive advantage n Added service for a user n Speeds task completion (I-Click) n Can require login n Cookies n Dynamic

Privacy Concerns n No right to privacy in US n Privacy Contracts n Request of personal information cause users to leave site n Highly related to trust

Trust Many factors affect trust: n Context n Perceived Similarity n Standing in organization n Behavior n Certification n References

Fostering Trust n Help establish credibility n Security Statement n Safe display of personal information n Use of secure servers n Confirmation of all costs n Confirmation of shipping address

Controlling Privacy n No standard for enforcing privacy in place n P 3 P standard developed n Enforces and exposes site’s privacy policy n Tools to inform users of compliance with their selected privacy policy

Trust (P 3 P)

Trust (P 3 P)

Privacy Bird

Privacy Bird Shows Embedded Content

Privacy Bird