technology in the form of scanners or video digitisers
enables the user to digitise images from TV, such as Star
Trek, or audio from a Gloria Estefan album.  Multimedia
systems have no built-in copyright protection mechanism
and are unable to check that the user has permission
before image or audio capture takes place.

So, suppose you came across images taken from a well-known
TV programme which were freely available on a Public
Domain Archimedes disk.  Is such material Public Domain or
copyright material?  99% of the time, it is likely to be
copyright material which has been used without permission.
The few exceptions to this might be where the video
material itself (which was subsequently digitised) is in
the Public Domain.  Organisations, such as the BBC, hold
stock film material which may fall into this category.
Photo libraries have supplied Public Domain photographs
for decades.  But such material is by far the exception,
rather than the rule.

If the material is indeed under copyright, it should be
realised that the copyright holder is under no obligation,
either legally or morally, to allow their work to be used
by anyone else.

It is important to realise that an object and its