1 Multimedia Literacy Taxonomy of Multimedia Objects

2 2 Learning Objectives Define and recognize linked objects in a multimedia application Understand the present-day limits of creating those objects Think about what new kinds of object there may be in the future as multimedia technology progresses

3 3 Learning Objectives (cont.) Discuss whether the digitization of media is making communication better or worse, and understand the appropriate role of technology

4 4 Overview Text Graphics Sound Video

5 5 Overview (cont.) Animation Software and Data Finding Multimedia Resources on the World Wide Web

6 6 Text Printed Text Scanned Text – Flatbed scanner – Handheld scanner – Sheet-fed scanner – Scanners translate printed text into machine readable form Newspaper Article from USA TODAY. Copyright 1994, USA TODAY

7 7 Text (cont.) OCR (Optical Character Recognition) software produces the text The caret (^) marks characters about which the scanner was unsure

8 8 Text (cont.) Electronic Text – Text in machine readable form Hypertext – Text that has been linked – The linked object is launched upon clicking – Links give the text an added dimension

9 9 Graphics - Bitmaps Bitmaps – Picture is stored as a set of pixels – Pixels correspond to the grid of dots on a computer screen – Each dot on the screen is set to the color specified in the bitmap – Bitmaps can be created with a graphics editor

10 Graphics – Vector Images Vector Images – Image is stored as a set of mathematical equations – Equations define curves, lines and shapes Vector Advantages over Bitmaps – Vector images are easily scalable – Vector images are smaller in file size

11 More Graphics Clip Art – Libraries of clip art are available online Digitized Pictures – Pictures are transformed into bitmaps – Can be still pictures or moving pictures Hyperpictures – Pictures that are used as triggers for multimedia events

12 Sound – Waveform Audio Waveform audio digitizers translate sound waves into digital form

13 Sound – Waveform Audio Table Digitized sound wave (Samples taken from the waveform on the previous slide)

14 Sound - MIDI MIDI (Musical Instrument Digital Interface) – Does not record the waveform – Records the performance information required for the computer chip to play the music – MIDI files have a.mid file extension

15 Sound – Audio CD Audio CD’s can hold up to 75 min of high- fidelity sound Sampling rate is 44,100 samples per second CD Plus, CD extra, Enhanced CD – Are music CD’s that also function as a CD-Rom – Computer data is included on the music disc

16 More Sound MP3 – MPEG Audio Layer 3 – High quality – Small file size – Popular for sound transmission on the Internet Hyperaudio – Sound that is used to trigger multimedia events

17 Video Live Video Feeds – Provide real-time video transmission Videotape – VISCA (Video System Control Architecture) allows video to be computer controlled Videodisc – CAV and CLV Digital Video – Stored in digital form

18 More Video DVD – Digital Versatile Disk – Uses MPEG-2 format – Holds up to 17 GB of data – Backward-compatibility allows playing of CD’s Hypervideo – Video that is used to trigger multimedia events

19 Animation Frame Animation – Displays a series of images (frames) in rapid succession – Threshold for the human eye to recognize flicker is 24 frames per second Vector Animation – Animation is stored as a series of mathematical equations – Macromedia has published the Flash file format (.swf) as an open standard

20 More Animation Computational Animation – Specifies coordinates for objects – Objects are moved by varying their x and y coordinates Morphing – Transitions one shape into another – Uses a series of frames to create a smooth movement

21 Morphing Example

22 Software and Data Seamless integration of objects is a powerful concept of Multimedia When triggers link to a particular object, the computer automatically launches the necessary software for this object