Presentation held at:
1992 Chemical Information Conference
1992, Annecy, France
The procedure to convert a scanned image of a page of chemical structure
diagrams (with accompanying text) into a set of connection tables is
one of the primary aims of the CLiDE project. These connection tables
can be used in a variety of computer-based applications such as building
and maintaining databases. The image is decomposed into component
graphics and text which are further analysed to find the lines,
wedges, and chemical text strings. In an interpretation phase the
connection tables for the molecules are build from these items.
The correct interpretation of chemical bonding in the image is often
hampered by the constraints of representing a three-dimensional
molecule in two dimensions where one bond may be drawn over another.
A method of identifying and successfully dealing with these situations
is described. A related situation where a bond is drawn crossing a ring
implying an undetermined point of attachment is also solved.
Examples are presented to illustrate these situations and the
rules implemented to handle these structures within the CLiDE