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The image

The chosen picture was presented to participants, without context, in four states of degradation: the full Web image of JPEG quality factor 75 and reduced images of quality factors 18, 12 and 6gif. After looking at the full quality image (see below), users were given the three degraded images and asked whether they would accept ``all or any of these'' in the context of a web-page they had requested.

The picture presented to them showed a room with ornamental detail in old furniture and a series of antique portraits. These details were fairly clear in the original image, but by the third degraded image (of quality factor 6), nothing except shape and disintegrated colour were evident.

The image was picked as holding enough detail - in its full state - to arouse detached interest or curiosity, but as being emotionally neutral. This was confirmed by the results of the first question, which asked for users' response to the full quality picture's content.

From the user's point of view, when using the Web there are two categories of image: the ones that the user actively searches to see and those that just arrive as part of pages (which can be further broken down into those which happen to arouse interest and those which do not). A ``neutral'' image modelled the haphazard condition and allowed for a similar response between users in terms of engagement. Other conditions were discussed.

Malcolm McIlhagga
Thursday June 11 16:17:19 BST 1998