Apparatus and method for subtyping window elements in a document windowing system

摘要

Methods and apparatus may include assigning a subtype, from a sub-class of image types, to a pixel, the subtype indicating membership in a window and also indicating a more specialized sub-class of image types. Membership in the sub-class may specify downstream processing specific to the subtype and compatible with the downstream processing of other subtypes within the sub-class. Such methods and apparatus may allow individual pixels within a window to receive specialized downstream processing according to their subtype while preventing objectionable artifacts. Such artifacts may result from classifying neighboring pixels as image types calling for mutually incompatible downstream processing.