Brightboard in Use
A camera fixed to the ceiling watches the activity
on the board. It is connected to a computer which
uses low-resolution images to detect when the user
has stepped aside and so is not obscuring the
board. The system then captures a high resolution
image, thresholds it, and attempts to recognise the
marks that are in the image.
Details of the marks found, their position, and
their type if recognised, are passed to a Prolog
engine which can analyse the relationships between
them and so determine if the combination of symbols
required to constitute, say, a 'Print' command are
present on the board. Appropriate actions can then
be taken.
There's a two-minute
video clip of BrightBoard in use which
you can view if you have a recent QuickTime player.