What is Multimedia?

Una DooneyUna Dooney MultimediaMultimediaSlide Slide 11

What is Multimedia?• A combination of different media

types such as text, graphics, audio, video and animation etc in a single application package

• Integration of what were previously considered separate methods of communication– A multimedia application combines at

least 3 of the media types mentioned above


What is Multimedia used for?

• To create an engaging learning environment

• To better communicate a message

• To make applications more interesting, interactive and effective


Why Use Multimedia?Studies have shown that as learners

– Listen they recall 25% of the material they hear

– Hear and see they will remember 50%

– And learners who hear, see, and interact with the material during the learning process will remember 75% of the material


In Education

• Multimedia training allows learners to take greater control of their own learning process

• Learners can move through courseware content at their own pace

• Student can retrace his/her steps


Communication

• Technology allows us to combine media to communicate a message

• By combining media it is easier to deliver the message


Advantages

• By using multimedia in your applications you can produce applications that are:– More Efficient– More Direct– Interactive


More Efficient

• You can replace information you read with information you can see and hear, such as a video clip

• This might convey the message in a more efficient manner

• Can access people who otherwise could not hear or see the message


Direct

• You can deliver information using the best medium

• Example: A language-teaching application that plays a native speaker’s voice to demonstrate pronunciation


Interactive

• It is easier to get user interaction with pictures and sounds than with plain text only

• Users are drawn to objects on the page/screen other than text

• If the application uses hypertext, users do not have to follow a single path but can choose which path to take


The Elements of Multimedia

• Text• Graphics• Sound• Video• Animation


Text

• Text often shapes the content of a multimedia application

• Different text formats depend on how the text was created

• Some formats are * .doc, *.txt and *.rtf• Text is easy to handle and store and

does not take up a lot of storage space• Text files are created using a word

processor


Graphics

• Add visual appeal to an application

• May express an idea more clearly

• Two main types– Bitmapped– Vector


Graphics - considerations

• Grapahics require a lot of storage space and RAM to work with

• There are many file formats: *.bmp *.pic *.gif *.tif *.jpg to name a few

• Needs a graphics application to create and edit pictures

• Display differently depending on the monitor resolution and colour settings of the computer


Graphics – Considerations• The resolution

– the number of pixels stored per inch of the image size

• The colour bit-depth– the number of colours stored for each pixel

within the image

• Each of these directly affect the file size of the stored image and its quality when displayed on screen or printed


Sound

• Speech, sound effects or music • Can be used to complement text or

to add a mood or emphasis• Sound has to be captured and

digitized• This is done using a microphone to

record voice or music and edited using sound-editing software


Sound• Can be recorded or

synthesized• Sound qualities

– Mono – single channel

– Stereo – 2 channels of amplification

– Quadraphonic – 4 channels

– Surround – 4-6 channels

Graphic representation of a sound wave


Sound - considerations

• Quality v storage requirements• Sample Rate – this is the number of

samples taken of the sound per second• The more samples the better the

quality but the larger the file. CD-quality is 44,100 samples per second (44.1 KHz)


Sound - considerations• Bit-depth or sample resolution – the

amount of information that is stored about each sound sample– 8-bit gives mono sound– 16-bit gives mono or stereo

• Channels – 1-channel is mono, 2-channel is stereo etc

• File formats are *.wav *.au and *.snd or *mid (for synthesized sound) and others


Video

• Made up of frames which are like still pictures or photos

• A few seconds of video may have hundreds of frames

• Need a video-editing application ie Adobe Premier


Video – considerations - Storage

• Most video needs compression because of the size of the original recordings

• Roughly 5 mins of video will need 1GByte of storage space before it is compressed

• A video is no more than an array of still images synchronized with a sound file


Video - considerations - File Size

• Video size on disk and in memory depends on– video playback window size [Frame Size]– the frame rate (how many frames are

played back each second) – the audio sample rate– type of compression used

• Common file formats are *.avi *.mov and *.mpg


Video – considerations

• Frames per second is an important factor– If the frame rate is too slow the video will look

like a slide show– TV quality 30 fps– Cinema quality is 24 fps– Web quality 10-15 fps

• Video applications will need a plug-in application to play on your computer screen (Windows Media Player or QuickTime)


Animation• Animation is "active

graphics" • It is really a type of

video • Common "pure"

digital animation file formats include *.FLC and *.FLI

• Many of the concerns of video also apply to animation ie size


Hardware Required

• A multimedia PC consists of these basic components

• A fast, powerful PC, a CD-ROM or DVD drive, an audio board, an operating system that can handle multimedia, a set of speakers or headphones for audio output and a microphone for recording sound (digitising) and a video-capture board for video input


You will also need

• Lots of hard disk storage and lots of RAM memory.

• A CD or DVD writer is now almost a necessity and is becoming standard with many new PCs


Software Requirements

• Software associated with each of the multimedia elements such as:– Flash for animations– PhotoShop or other graphics software for

graphics creating and editing – Video and sound editing software ie Adobe

Premiere– Compression software to make files smaller– Plug-in software – QuickTime, Media Player


Bringing it All Together

• To put your multimedia application together you need a multimedia authoring package to assemble the files into a single application ie Macromedia Director

• You will also need an optical storage medium such as CD or DVD

• Some applications such as PowerPoint allow you to incorporate multimedia objects into a presentation but are not true authoring packages

Documents

What is Multimedia?