It seems fitting, in order to conclude the discussion of the previous pages, to go beyond the purely technical exposition to look at the organisation of video (and other data) from a broader perspective. Cameras are becoming cheaper and smaller, and are being placed in many places in which, only a few years ago, their presence would have been unthinkable. This is not an entirely new phenomenon but what is new today is the possibility of inserting these video data into a world-wide network in which they can be analysed, associated to other information, and accessed in a much more convenient way than it was possible before.
The possibility of organising information along semantic lines, and of associating different sources of information around meaningful events, transforms the quantitative increase in the amount of information available into a qualitative leap of the modalities of access of information, a leap fraught with possibilities but also with dangers.
Issues like the people's right to privacy (indeed the very concept of privacy), and the control of information about one's life are already at the centre of the public's attention. Large scale data organisation and association will bring forward other issues, more subtle and complex, like the control of the inferences that can be made based on publicly available data: it is well known that even apparently harmless pieces of information can, if accumulated in suitable amounts and analysed with sufficient sophistication, be used to infer information that a reasonable person would consider an intrusion of privacy.
These issues are not eminently technical in nature, but should generate a social, cultural, and political debate in all strata of society. Hopefully, computer professionals will be an active and socially conscious part of this debate. Too often in the past we have seen the role of computer professional reduced to that of technical developers without a voice or, worse, of an amplifier for the voice of the commercial interests of the companies for which they work. As the social issues related to computer technology become more momentous and more pressing, it is essential that the developers of such technology become an active and informed part of the social debate on those issues.