Digital data formats for representation of real objects

Adolf KnollNational Library of the Czech Republicadolf.knoll@nkp.cz

Which objects to represent?

Discrete chunks of reality perceivable by our senses: Visual objects (still images) Audio objects (sounds) Video objects (moving images) Abstract objects (evoked through text)

Mixed objects, eg. audiovisual ones Digital data objects are created through

direct transformation of these chunks of reality.

Digital audio and video

Click on image to see video and on icon to listento music

How are they created?

Directly Digital photo

camera Digital sound

recording Digital video

recording Digital text input

Indirectly through analogue representation Classical

photograph Analogue sound Analogue video Typewritten text

Digitization produces computer file(s)

The analogue signal is digitized

Analogue encoding Continuous For sound must be

interpreted as well Motion pictures are

based on illusion made by moving discrete analogue images/frames

Digital encoding Discrete elements Must be rendered

into analogue Motion pictures are

based on illusion made by moving discrete digital images/frames

Man can perceive and understand only analogue rendering of information.

REAL WORLD vs. ENCODED WORLD