Info Sys - Applied Multimedia - Implementation

PRESENTATION

• Used to create linear MM presentations
• It is possible to combine text, graphics, audio and video
• Transitions between and animations within slides can be used
• Hyperlinks can be incorporated but the product is essentially linear

WEB PAGE APPLICATIONS

• Can be viewed over the internet which increases the audience
• Web page editors can range from basic HTML editors that allow you to create individual pages
• to website managers which will design and handle all aspects of web managment

Authoring software combines text, graphics, audio & video using either icon or script based software

Authoring packages create a UI where the user can control a cast of MM objects and define how they all react

ICON BASED

developer can build a flow chart of different events by dragging them from a predefined palette

text, graphics, audio & video can be added. icons can be used to represent audio & video

certain icons will have properties that describe flow control and user interaction

ADV: structure is easy to follow

        easy to edit & update information

DIS: can be difficult to learn (however easier than scripting based)

provides a scripting facility

timebased tool and a score are the primary authoring metaphor

elements are presented in horizontal tracks with vertical columns (timelines)

using scripts to control the behaviour of cast members a powerful presentation can be built

code can allow scripting using english words and phrases. developers can use prewritten scripts or write new ones which can simply be dragged and dropped onto the timeline

it can take a long time to be able to write scripts from scratch- previous programming knowledge can be an advantage

Once created the application can either be turned into a stand-alone file which will run without needing software to play it or saved in an a format which requires a software player

STAND-ALONE

more difficult for the MM developer as it raises compatability issues

once created it requires no other software so it can be sold as a complete package

FORMAT WHICH REQUIRES A SOFTWARE PLAYER

depends on the user having a player installed on their system

an animation, created with macromedia flash, will require the appropriate flash player to be installed to view the animation

Project Manager

• works closely with client
• accountable for ensuring that the development meets the client's requirements, is created to a high standard, within budget & on time
• involved with the scope and design of the application
• assembles all team members to ensure they are the correct people for the post
• require high managerial and communication skills

MM Designer

• specalise in the overall design and in the combination of different media
• responsible for content, structure, navigation, screen layout & interactivity
• works closely with all technical staff
• will implement design by utilising relevant members of the team

Subject Expert

• has an in-depth knowledge of the particular subject
• important in testing

Media Specialists

• expert in  creating media elements in their own area of expertise
  • e.g. video/audio engineers, animators or graphic designers

MM Programmer

• responsible for creating the overall application to the design provided by the MM designers
• incorporating media elements provided by media specialists
• expert in chosen software or authoring tool

Webmaster

•  administers the website
• in charge of webserver hardware/software, website design & update and monitoring feedback andtraffic

Graphic file types can be compared in terms of

• colour depth - number of colours that can be represented in a pixel (8, 16, 24, 32 bit)
• resolution - number of pixels per unit area
• file size - bytesof storage space used to store a graphic
• degree of compression - determines image quality lossy/lossless
• appropriate uses

TIFF (Tagged Image File Format)

• developed for scanned images
• widely supported file format
• lossless compression at various rates
• can be any colour depth and resolution
• file size larger than JPEG or GIF
• used for scanned images, DTP

JPEG (Joint Photographic Experts Group)

• mainly used on web as a good quality image with a small file size
• lossy compression built into the format
• can use any colour depth (16, true, 32) and resolution
• small file sizes (compression can reduce to 5%)
• used for photographs for web display, low resolution print

GIF

• mainly used for web images with sharp content (logos/screenshots)
• lossless compression
• output to any resolution
• 8 bit colour depth - small
• small file sizes
• interlacing, animation & transparency available
• used for graphics withlarge areas of uniform colour, clip art

MP3 (Motion Picture Expert Group, Layer 3)

• digital audio compression format - can reduce sound file 10-15 times smaller
• eliminates waveforms that the human ear cannot process 
• easy and quick to download - perfect for web download
• needs an MP3 player to listen to files
• used extensively on music websites
• small file size
• compression can be 6:1
• used for music downloads from web

MIDI (Musical Instrument Digital Interface)

• doesn't store sampled sound - stores binary instructions
• fast downloads anduses little space in memory
• only stores instructions for the sound card to recreate
• allows the user to create sounds without using an audio based input source
• small file size
• no compression
• can be embedded in web pages, easy manipulation/download

Video file size & quality are affected by: frame rate, window size, compression rate

Frame Rate

• one frame is one complete picture in the reel of a film
• many frames are shownin one second to create the effect of motion
• frame rate is the unit of measurement - in frames per second (fps)
• film has 24fps but it must be adjusted to match the display rate of the video system
• higher frame rate = smoother picture
• a key frame is included every 15 frames to allow audio & video to be synced and prevent overlap problems

Window Size

• smaller window sizes require less time for all the pixels to be drawn - larger window sizes mean that there may not be sufficient time to display the whole picture before the next appears
• an appropriate window size needs to be chosen to ensure a smooth display
• reducing the window size will reduce the file size

COMPRESSION

• video displayed over the web must be compressed so that it is a more realistic delivery size
• encoding is used involving a codec (compressor/decompressor)
• codecs work removing data from the file and replacing it when it is decompressed
• user can select a quality setting for compression - lower setting=greater compression, smaller file size & weaker quality overall

MPEG (Motion Picture Expert Group)

• large files (30 fps) which output high quality playback
• MPEG requires special hardware to digitise video and specific hardware for playback
• not compatable on Mac OS

a URL (uniform resource locator) uniquely specifies the address of a file on the web

each address is represented in its alphanumeric form

URL format:

protocol://hostname/path/fiename

OR protocol://hostcomputer.domainname.domaintype/pathname/file.extension

e.g. www.getrevising.com/revision-cards/info_sys_applied_multimedia_implementation

• protocol - HypertextTansfer Protocol = http
• host name - www.getrevising.com
  • host computer - world wide web = www
  • domain name - getrevising
  • domain type - commercial = .com
• path name = revision-cards
• filename = info_sys_applied_multimedia_implementation

Protocols

web pages are constructed in HTML and served from a http server

Host Name

includes host computer, domain name & domain type

domain types:

•  
  • .com - commercial entity
  • .org - organisation (nonprofit/charity)
  • .ac - academic institution
  • .org.de - german organisation

Path Name

specifies the location of the file on the computer system

ABSOLUTE

the fully qualified URL - includes the host name & full path name of file

http://www.getrevising.com/revision-cards/info_sys_applied_multimedia_implementation

^ this is an example of an absolute URL - it has specified the http service on the www system located at the getrevising.com domain and is asking for info_sys_applied_multimedia_implementation file in the revision-cards directory

REALTIVE

location of the file relative to the location of the file currently being used. Directions refer to where you are starting from soit does not need to specify protocol or machine name:

/revision-cards/info_sys_applied_multimedia_implementation

points to the folder revision-cards which contains the file info_sys_applied_multimedia_implementation the relative URL only needs the folder & file name as it can assume that the current server is the requested computer system