One or more response bubbles are used on a scannable form to be read by a
scanning system. An unambiguous symbology of marks is defined to fill
into each response bubble, thereby allowing at least one of a plurality
of different non-empty intended responses having different output values
to be entered into each response bubble. One or more response bubbles are
provided on the scannable form to be filled in according to the defined
symbology of unambiguous marks. A filled in form is scanned with the
scanning system and an image of the scanned form is processed by
identifying pixels associated with each response bubble, interpreting the
pixels associated with each response bubble to define a raw score
according to the defined unambiguous symbology of marks used to mark each
response bubble, translating the raw score for each response bubble into
one of the plurality of different intended non-empty responses, and
outputting the value of the non-empty response for each response bubble.
Different output values have different meanings.