Digital Documents and Libraries Adolf Knoll National Library of the Czech Republic [email protected] © Adolf Knoll, National Library of the Czech Republic.

Digital Documents and Libraries

Adolf KnollNational Library of the Czech [email protected]

© Adolf Knoll, National Library of the Czech Republic

Communication

Creator of

information

Receiver of

information

Informationdelivery

Receiver of

information

Receiver of

information

Receiver of

information

Receiver of

informationMultiplyinginformation

What is transmitted?

Information that can be perceived by human senses: smell (we can receive the smell of the cooked

meals) taste (we can taste the wine) touch (we can touch various objects to discover

their properties) hearing (we can hear information, e.g. music) sight (we can see objects)

What is emitting information?

Physical Object

Artefact

•It smells well•It cools when touched•It can be seen•It tastes well•It can be heard when opened and even poured in glasses

However, what remains from this informationif the artefact and the action are encoded in a document ?

What is a document?

A surrogate of the reality,its reflection fixed (written) on a physical carrier.

How this surrogate works?

… and if it is sound,

how does it work for me?

It makes me rememberspecific moments of mypersonal life

… variety of remembrance

For you?

For me?

No context

Rich context1234

What a document can transmit?

The document bridges two worlds: that of the its creator and that of the receiver of the information message.

Each receiver processes the same information message differently: during its interpretation, he uses his knowledge, his experience, his own feelings.

Thus, the results differ from one another.

Basic message

Basicmessage

Basicmessage

Basicmessage

Original Document Recreated original

Addedinformation

Addedinformation

Created work

CreatedWork

Multiplied distribution copies

UnderstoodWork

Multiplying information

Growing possibilities manual copying (from inscriptions in

stone to manuscripts produced in scriptoria)

printing (the number of copies grows) analogue copying (Xerox, audio

recordings, motion pictures, ...) digital copying and delivery

Problems

Fidelity of copied information Durability of information carrier Decoding process

These factors have a strong influence on our understanding of what the creator wanted to share with us.

End

Fidelity

The digital copying can solve the fidelity, because we are able to copy all the bits.

However, digitization is not copying, it is re-encoding of information into another system.

Digitization is conversion of the analogue scheme into the digital scheme.

Any change of parameters of the digital format or any conversion

from one digital format into another can affect the fidelity.

Change of parameters

Digital audio recording - reducing the bit rate: MP3 128 Kbit/s MP3 34 Kbit/s

Digital image - reducing the number of colours: 256 colours 16 colours 2 colours

256 colours/8 bit

16 colours/4 bit

2 colours/1 bit

Converting between digital formats

Through this conversion losses of information can take place.

In order to avoid this situation, we must know the characteristics of the most used digital formats.

E.g.: converting from JPEG into GIF, we reduce the number of colours.

Durability of information carriers

In the analogue world, this is the most critical problem.

In the digital world, it is a problem of good organization of digital archiving system.

The problem can be high amount of carriers to be monitored - certain reliability of CDs (the redundancy of written-on information can be measured; the copying should be made before reaching the critical point)

Decoding process

The decoding process is the most critical point in both analogue and digital worlds.

The only difference is that the development of digital schemes and platforms is faster. This is an Egyptian

papyrus; we can stillread it and understand it.

Latin

Iste liber pertinet ad dominam abbatissam de convento Georgio Chunegundemfiliam Othakari Regis Bohemie.

Etruscan

The carrier is well preserved.The letters are evident. Nobody understands the message.

Digital resources

Digital Library

On-line externaldocuments

In-house digitizationproducts

Physical mediadocuments

Physical media documents

Issued by various publishers CD, DVD, diskette Great variety of application/access

software versus uniformity of audio CD National Libraries face their long-term

preservation The documents include also software

releases and games

Physical media documentsCritical factors

Information carrier: unreliable diskette and relatively reliable CD (possibility to measure the data redundancy)

Access software: very critical Data and metadata formats: very critical SW/HW platform dependence

We must try to keep them unbound as much as possible from one another.

Access software

HW SW

Metadata

Data

On-line external documents

We do not acquire them physically, we do access them on networks

Should we try to preserve them as NL? What is their storage format? What we see, it is frequently a transient

document formatted for us (often into HTML) or a part of a static source only.

On-line external documents

Data SourceData Source

request

delivery

Partialor

TransientDocument

Partialor

TransientDocument

In-house digitization and publications

Great chance to behave cleverly To consider all the possible long-term access

problems before to start This can cost more now, but it will surely save much

more money in future The most general recommendation:

STICK TO THE MOST WIDESPREAD STANDARDS

for developing your applications.

In-house digitization and publications

Once started, we are responsible for availability of our products.

Production

Production

ResearchDevelopment

ResearchDevelopment

Trying to describe the relevant aspects of these activities.