Scor­pio News

  

April–June 1988 – Volume 2. Issue 2.

Page 29 of 35

What does ‘Digital’ mean ?

Now the whole thing is ‘digital’ – is this another bit of hype from the promotions boys, as ‘digital’ doesn’t seem to mean digital these days, it means a sort of woolly association with computers, latest technology and of course, is good for you whether it’s got anything to do with being digital or not. Like the word quartz, another piece of ‘word specialisation’ which the promo boys have foist upon us. Quartz is a silicate mineral – a lump of rock, nothing more, nothing less – it’s certainly not an adjective to be used in place of the phrase ‘precision timekeeping’. That’s not how the promotions guys would have it.

No, digital imaging is nothing to do with promotions, it is truly digital and a brief explanation of ‘digital’ is necessary. Digital information consists of binary codes, and binary codes are often referred to as a system of counting in ‘0’s and ‘1’s. This is true but confusing, better to say binary codes can represent almost anything if applied properly and the business of ‘0’s and ‘1’s is better presented as the presence or absence of something rather than anything to do with counting. Binary codes imply something to do with computers – not true. Binary codes could be written and manipulated using matchsticks. Line up a row of, say, twenty matchsticks away, equally spaced apart. In this case we’ll say the matchsticks represent ‘1’s. The row of matchsticks represents a binary code. Now take: some of the matchsticks away, may be just a couple perhaps all of them, perhaps none. The absence of a matchstick will represent a ‘0’. The code you are left with is another binary code – totally meaningless in this case as the original code didn’t represent anything in particular in the first place, but a binary code none the less, and you didn’t need a computer to manipulate it – to remove the matchsticks. Another couple of quick definitions – each individual ‘0’ and ‘1’ is known as a ‘bit’ and a collection of eight ‘bits’ is known as a ‘byte’

The computer handles digital information, but as we’ll see later, there’s digital information and there’s digital information. Important to our case is the difference between the handling of an image in a computer and the way in which a computer handles text. In our own minds there’s a clear distinction between text in the form of written words on one hand and on the other hand, pictures. You read words – you look at pictures. The process is totally unconscious, your mind says “This is text, read it” or presented with a picture, your mind says “This is a picture, look at it”. But that’s not to say that a piece of paper covered with words is not a picture. Think about that, stand back from any printed page and the text takes on grey shapes, you can’t make out the words, but the shape of the blocks of text is quite distinct. Can you see that a page of words could be a picture ? Is the converse true ? A picture consisting of words is not necessarily text. Looking close up at a picture made up of words and the words might read as gibberish. So we have established a simple rule: a picture is a picture; text is a picture; but a picture is not necessarily text.

Page 29 of 35