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Lecture 8 Overview Hypertext, hypermedia The WWW Animation and video Applications Mobile devices Introduction Increase in computing power led to the rapid growth of multimedia industry. There was great change from having static info being displayed to the display of moving images. Multi-Sensory Systems More than one sensory channel in interaction e.g. sounds, text, hypertext, animation, video, gestures, vision Used in a range of applications: particularly good for users with special needs consideration: speech non-speech sounds Auditory icons handwriting text and hypertext animation and video WWW Multi-modal versus Multi-media Multi-modal systems • use more than one sense (or mode ) of interaction • e.g. visual and aural senses: a text processor may speak the words as well as echoing them to the screen Multi-media systems • use a number of different media to communicate information • e.g. a computer-based teaching system: may use •video, •animation, •text and •still images: different media all using the visual mode of interaction. may also use sounds, both speech and non-speech: two more media, now using a different mode. Text and Hypertext • The idea for hypertext (where documents are linked to related documents) is credited to Vannevar Bush's famous MEMEX idea from 1945. • Tim Berners-Lee used the hypertext idea to create the World Wide Web in 1990 at the government-funded European Particle Physics Laboratory (CERN). Mosaic, the first popular hypertext browser for the World-Wide Web was developed at the Univ. of Illinois' National Center for Supercomputer Applications (NCSA). Text is a common form of output, and very useful in many situations • imposes a strict linear progression on the reader, the author’s ideas of what is best - this may not be ideal Hypertext structures blocks of text into a mesh or network that can be traversed in many different ways • allows a user to follow their own path through information • hypertext systems comprise: - a number of pages, and - links, that allow one page to be accessed from another Hypertext Non-linear bookmark home this is text or is it hypertext only links can tell this is text or is it hypertext only links can tell this is text or is it hypertext only links can tell this is text or is it hypertext only links can tell this is text or is it hypertext only links can tell back link external link this is text or is it hypertext only links can tell this is text or is it hypertext only links can tell this is text or is it hypertext only links can tell Hypermedia They allow user oriented access to info and support browsing. Hypermedia systems are hypertext systems that incorporate additional media, such as illustrations, photographs, video and sound Particularly useful for educational purposes • animation and graphics allow user to see things happen • hypertext structure allows users to explore at their own pace Problems • “lost in hyperspace” - users unsure where in the web there are maps of the hypertext are a partial solution • incomplete coverage of information some routes through the hypertext miss critical chunks • difficult to print out and take away printed documents Examples: Microsoft windows help, Sun guide system, HyperCard help Web Basics … Protocols and browsers, web servers and clients, networking the ‘web’ – protocols and standards HTTP – to carry information over the internet HTML, XML and graphics formats for content browsers to view the results … plus plug-ins changing use initially research (CERN - high energy physics) now corporate, government, commerce and entertainment, advertising, community The WWW Best known multimedia hypertext system Offers an environment for the presentation of information, also act as effective interactive tools. The Web supports; •Hypertext •Graphics, icons, photos, background,……. •Sound & movies (dynamic materials) •Uses HTML to structure & describe the information. challenges lost in hyperspace, information overload HTML is …… WWW Design Focus HCI design focus; informative, interactive, attractive and easier to use sites. Consider: •Underlying limitations/capabilities of the medium: (both human and computer) •The user as a central focus of the design. •Webpage design supported by HTML •Web protocols Message and medium: 1. 2. 3. Content Attractive pages (page layout) Information structure (navigation) • Allow User to be in control • Hierarchical structure • Navigation buttons (home,………..) 4. Text (style, font, color,…….background…, alignment, …. Graphics; (take long to load), formats, purpose,… Icons; Movies and sound; video clips – sound? Networking - think about download time, connection time, feedback, Web color 5. 6. 7. 8. 9. the message and the medium “content is king” the catch phrase of dot.com era … but widely ignored the message … content should be appropriate to the audience, timely, reliable , …. generally worth reading ! the medium … page and site design good design – essential to attract readers … but won’t hide bad material! bad design – may mean good material never seen printable! Text text style generic styles universal: serif, sans, fixed, bold, italic specific fonts too, but vary between platforms cascading style sheets (CSS) for fine control … but beware older browsers and fixed font sizes colour … often abused! positioning easy .. left, right justified or centred precise positioning with DHTML … but beware platforms … screen size mathematics … needs special fonts, layout, Graphics • use with care … – N.B. file size and download time … this image = 1000 words of text – affected by size, number of colours, file format – backgrounds … often add little, hard to read text • speeding it up – caching – reuse same graphics – progressive formats: • image appears in low res and gets clearer Formats •JPEG – for photos-higher compression but ‘lossy’ get ‘artefacts’ •GIF for sharp edges-lossless compression •PNG supported by current web browsers •and action animated gifs for simple animations image maps for images you can click on Icons • on the web just small images – for bullets, decoration – or to link to other pages – lots available! • design … just like any interface – need to be understood – designed as collection to fit … Web Color • how many colours? – PC monitors – millions – 24 bits per pixel … but the ‘same’ colour may look very different • N.B. usually only 72–96 dpi – older computers, PDAs, phones … • perhaps only 16 bits or 8 bits per pixel … 256 colours • or even greyscale • colour palettes – choose useful 256 colours – different choices, but Netscape ‘web safe’ 216 are common – each GIF image has its own palette – use for fast download Movies & Sound • problems – size and download… like graphics but worse! – may need special plug-ins – audio not so bad, some compact formats (MIDI) • streaming video – play while downloading – can be used for ‘broadcast’ radio or TV Animation adding motion to images for things that change in time digital faces – seconds tick past or warp into the next analogue face – hands sweep around the clock face live displays: e.g. current system load for showing status and progress flashing carat at text entry location busy cursors (hour-glass, clock, spinning disc) progress bars Animation for education and training let students see things happen … as well as being interesting and entertaining images in their own right for data visualisation abrupt and smooth changes in multi-dimensional data visualised using animated, coloured surfaces complex molecules and their interactions more easily understood when they are rotated and viewed on the screen for animated characters wizards and help Utilizing animation and video Animation and video are potentially powerful tools • notice the success of television and arcade games However, the standard approaches to interface design do not take into account the full possibilities of such media We will probably only start to reap the full benefit from this technology when we have much more experience. We also need to learn from the masters of this new art form: interface designers will need to acquire the skills of film makers and cartoonists as well as artists and writers. Video & Audio •now easy to author •tools to edit sound & video and burn CDs & DVDs •easy to embed in web pages •standard formats (QuickTime, MP3) •still big … but getting manageable •memory OK … hand held MP3 players, TiVo etc. •but download time needs care – tell users how big! •very linear •hard to add ‘links’ often best as small clips or background Issues Audio: annoying if unwanted, Delivery Technology •on the computer •help systems installed on hard disk with applications •CD-ROM or DVD based hypermedia •on the web •really ubiquitous! •in many countries, near universal internet access •not just web pages! •e.g. many applications have web-based documentation •mobile phones, PDAs, laptop computers •delivery CD-ROM or DVD (like desktop) cached content (e.g. AvantGo) WiFi access points or mobile phone networks WAP – for mobile phone, tiny web-like pages Applications of WWW rapid prototyping create live storyboards mock-up interaction using links help and documentation allows hierarchical contents, keyword search or browsing just in time learning what you want when you want it (e.g. technical manual for a photocopier) technical words linked to their definition in a glossary links between similar photocopiers education animation and graphics allow students to see things happen sound adds atmosphere and means diagrams can be looked at while hearing explanation non-linear structure allows students to explore at their own pace e-learning letting education out of the classroom!! e.g. eClass eClass (formerly Classroom 2000) an ordinary lecture? slides, pen marks, video are ‘captured’ ... available later through web interface Lost in Hyper Space •non-linear structure very powerful … but potentially confusing •two aspects of lostness cognition and content •fragmentary information – no integration … confusion •navigation and structure hyperlinks move across structure – where am I? no easy solutions but good design helps! Making Navigation Easier •maps •give an overview of the structure •show current location – you are here! •recommended routes •guided tour or bus tour metaphor •linear path through non-linear structure •levels of access •summary then progressive depth •supporting printing! •needs linearised content, links back to source History & Bookmarks • Revisiting hub and spoke’ access – click-back-click-back lots of revisiting of pages back’ is 30% of all browser navigation but multi-step back and history used less bookmarks and favourites for longer term revisiting • Deep links bookmarks and external links – into heart of site are pages self explanatory? what site? where in it? • Frames difficult to bookmark, search and link to but some good reasons for use (see /e3/online/frames/) Indices, Directories & Search • Index often found in help, documentation, … even books selective: not an exhaustive list of words used •Directories on web index would be huge! so hand chosen sites e.g. open directory project, Yahoo! •Web search engines ‘crawl’ the web following links from page to page build full word index (but ignore common ‘stop’ words) looks up in index when you enter keywords to find pages Mobile devices Mobile Web The Mobile Web refers to the use of Internet-connected applications, or browser-based access to the Internet from a mobile device, such as a smart phone or tablet computer, connected to a wireless network. What is a Mobile Device? A mobile device, which is also referred to as a handheld, handheld device or handheld computer, is a pint-sized computing device. Mobile devices usually come with a touch or non-touch display screen and sometimes, even a mini keyboard. What Makes a Mobile Device? Highly Portable Can be carried in a pocket or purse It's a constant companion Small Display Used in a public setting Whereas PCs are used in a private setting One per person vs. multiple PCs for home and work that are shared with others Mobile •Small screen - little information to view at once •Mobile - even while the task is being done •Limited tasks - user expects to perform emergency, quick, focused tasks to keep him mobile Non-Mobile •Large screen - lots of information to view at once •Stationary - at least for the task being done •All inclusive - user expects to perform any task to get the job done. Usability guidelines for websites on mobile devices Reduce the amount of content Not everything shown on a PC site can fit reasonably onto a mobile web page, where space is short and every pixel counts. It's important to reduce the amount of content shown on the mobile-optimized version. Carefully select content: Tailor the content specifically to the target user group by displaying only the most essential data. Usability guidelines for websites on mobile devices Single column layouts work best Wide web pages are difficult to view on small mobile phone screens. Even on smart phones like the iPhone with their relatively large screens standard web pages load up zoomed out so that they can fit on the screen. Instead, create single column pages that use up the whole width of the screen. To add additional content the page should expand downwards rather than across, as scrolling down is easier than scrolling across. Usability guidelines for websites on mobile devices Limit graphics: Graphics are an excellent way to spice up a Web site, but their use is questionable when working with small screens. Also, many handheld devices feature monochrome displays, so rich color graphics are lost. Minimize text entry Entering text onto websites using mobile phones is much more difficult than when using a desktop or laptop keyboard. It stands to reason, then, that users don't want to have to type as much on mobile websites. Ways to reduce the amount of text entry Ways to reduce the amount of text entry required include: Allowing users to use stored details in their 'My Account' section when going through a mobile checkout experience e.g. picking from previously entered delivery addresses. Asking users to enter a PIN instead of a password. Take advantage of inbuilt functionality. Design for mobile browsers A mobile browser, also called a microbrowser, minibrowser, or wireless internet browser (WIB), is a web browser designed for use on a mobile device such as a mobile phone or PDA. Mobile browsers are optimized so as to display Web content most effectively for small screens on portable devices. Mobile browser software must be small and efficient to accommodate the low memory capacity and low-bandwidth of wireless handheld devices. The Good of Mobile Design Probably the best thing about mobile web design is the mobility. Anyone, anywhere can access the Web in the palm of their hands anytime that they want. There is no demand of sitting at a big desk to surf the Internet anymore. Another advantage about mobile web design becoming more popular is it opens a whole new door up to new and existing clients for web developers. The Bad of Mobile Design Some of the disadvantages to surfing the web on a cell phone or mobile device is its small screen size, and slower loading time. Web browsing is a lot different on a cell phone than a computer. Developers need to figure out how to design a page that is attractive even in a small area and still give the same info the user needs. Mobile Website and an App A mobile website is similar to any other website in that it consists of browser-based HTML pages that are linked together and accessed over the Internet (for mobile typically WiFi or 3G or 4G networks). The obvious characteristic that distinguishes a mobile website from a standard website is the fact that it is designed for the smaller handheld display and touch-screen interface. Mobile Website and an App Apps are actual applications that are downloaded and installed on your mobile device, rather than being rendered within a browser. Users visit device-specific portals such as Apple’s App Store, Android Market, or Blackberry App World in order to find and download apps for a given operating system. Which is Better – an App or a Mobile Website? The most appropriate choice really depends on your end goals. If you are developing an interactive game an app is probably going to be your best option. But if your goal is to offer mobile-friendly content to the widest possible audience then a mobile website is probably the way to go. Generally speaking, a mobile website should be considered your first step in developing a mobile web presence, whereas an app is useful for developing an application for a very specific purpose that cannot be effectively accomplished via a web browser. Advantages of a Mobile Website vs. Native Apps Immediacy – Mobile Websites Are Instantly Available A mobile website is instantly accessible to users via a browser across a range of devices (iPhone, Android, BlackBerry, etc). Apps on the other hand require the user to first download and install the app from an app marketplace before the content or application can be viewed Compatibility – Mobile Websites are Compatible Across Devices A single mobile website can reach users across many different types of mobile devices, whereas native apps require a separate version to be developed for each type of device. Reach – Mobile Websites Have Broader Reach Because a mobile website is accessible across platforms and can be easily shared among users, as well as search engines, it has far greater reach capability than a native app. Advantages of a Mobile Website vs. Native Apps A Mobile Website Can be an App! Just like a standard website, mobile websites can be developed as database-driven web applications that act very much like native apps. A mobile web application can be a practical alternative to native app development. Time and Cost - Mobile Websites are Easier and Less Expensive Last but certainly not least, mobile website development is considerably more time and cost-effective than development of a native app, especially if you need to have a presence on different platforms (requiring development of multiple apps). Constraints of designing for Mobile Devices The constraints of mobile devices make them a challenging platform to design for. The constraints include: limited input controls (keys, keypad) and small screen size. Also, devices by different manufacturers or with different navigation approaches have varying configurations. Often a service needs to be designed for multiple devices and that adds complexity for designers. Additional Constraints in developing countries When designing and implementing mobile solutions for developing countries, the interaction designers must consider a wide range of challenges beyond technical issues, such as: Illiteracy or semi-illiteracy among users. Low computer literacy, i.e. no or highly limited knowledge prior knowledge of computer interfaces and established metaphors and paradigms like folders, drop down menus. Language barriers and dialects. Physical impairment of users. Social and cultural differences resulting in different mental models and patterns. Economic constraints. WAP - web on the phone N.B. larger screens and faster connections mean WML giving way to small HTML pages very small screen scrolling painful small ‘pages’ GSM connection slow big chunks WML (wireless mark-up language) content delivered in ‘stacks’ of ‘cards’ cards are the ‘pages’ the user views but navigation within the stack fast syuh syuh how how gtw gtw hsio hsio ii ert ert ag ag ty ty ghn ty ty we we ghty ghty syuh how gtw ghn chdi syuh oatyf how hsio i ert ag ty chdi qw qw syuh oatyf how gtw gtw wet dfla dfla hsioght ght ert ag ty ty ghn ty we ghty wet hsio ii ert aa ag ghn ty we ghty chdi qw syuh oatyf how gtw ghn ty we ghty chdi qw qw syuh oatyf how gtw hsioght i ert a ag ty chdi syuh oatyf how gtw wet dfla wet dfla hsio ght i ert a ag ty ghn ty we ghty wet dfla hsio ghti ert a ag ty ghn ty ty we we ghty ghty chdi qw syuh oatyf how gtw ghn chdi wet dfla hsio ghti ert a ag ty chdi qw qw oatyf oatyf wet dfla dfla ght ght aa ghn ty we ghty wet chdi qw oatyf wet dfla ght a navigation within stack fast server sends whole stack using WAP protocol syuh how gtw hsio i ert ag ty ghn ty we ghty chdi qw syuh oatyf how gtw wet dfla hsioght i ert a ag ty ghn ty we ghty chdi qw syuh oatyf how gtw wet dfla hsio ghti ert a ag ty ghn ty we ghty chdi qw oatyf wet dfla ght a syuh how gtw hsio i ert ag ty ghn ty we ghty chdi qw syuh oatyf how gtw wet dfla hsioght i ert a ag ty ghn ty we ghty chdi qw syuh oatyf how gtw wet dfla hsio ghti ert a ag ty ghn ty we ghty chdi qw oatyf wet dfla ght a syuh how gtw hsio i ert ag ty ghn ty we ghty chdi qw syuh oatyf how gtw wet dfla hsioght i ert a ag ty ghn ty we ghty chdi qw syuh oatyf how gtw wet dfla hsio ghti ert a ag ty ghn ty we ghty chdi qw oatyf wet dfla ght a syuh how gtw hsio i ert ag ty ghn ty we ghty chdi qw syuh oatyf how gtw wet dfla hsioght i ert a ag ty ghn ty we ghty chdi qw syuh oatyf how gtw wet dfla hsio ghti ert a ag ty ghn ty we ghty chdi qw oatyf wet dfla ght a server stores ‘stacks’ of cards errata: book says stacks of ‘notes’, cards is correct References 1. Bush, V., "As We May Think." The Atlantic Monthly, 1945. 176(July): pp. 101-108. Reprinted and discussed in interactions, 3(2), Mar 1996, pp. 35-67. 2. Nielsen, J., Multimedia and Hypertext: the Internet and Beyond. 1995, Boston: Academic Press Professional.