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Pen-Stroke Object Selection and Identification

IP.com Disclosure Number: IPCOM000117702D
Original Publication Date: 1996-May-01
Included in the Prior Art Database: 2005-Mar-31
Document File: 4 page(s) / 169K

Publishing Venue

IBM

Related People

Hanson, G: AUTHOR [+2]

Abstract

Disclosed is a solution for the confusion naturally resulting when several users mark-up a single document page in a computing system, using, for example, a pen-based user interface. This solution includes the use of identification attributes, stroke grouping, selection services, and group services. Identification attributes, such as color, line width, and certain multimedia signatures, clearly distinguish pen strokes, or collections of strokes, from one another. Stroke grouping collects multiple strokes into meaningful sets. For example, strokes are collected into characters, characters into words, and words into sentences. Selection services allow the user to alter and view identification attributes, to hide or show particular strokes according to those attributes, and to select stroke groups for manipulation.

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This is the abbreviated version, containing approximately 33% of the total text.

Pen-Stroke Object Selection and Identification

      Disclosed is a solution for the confusion naturally resulting
when several users mark-up a single document page in a computing
system, using, for example, a pen-based user interface.  This
solution includes  the use of identification attributes, stroke
grouping, selection services, and group services.  Identification
attributes, such as color,  line width, and certain multimedia
signatures, clearly distinguish pen  strokes, or collections of
strokes, from one another.  Stroke grouping  collects multiple
strokes into meaningful sets.  For example, strokes are collected
into characters, characters into words, and words into sentences.
Selection services allow the user to alter and view identification
attributes, to hide or show particular strokes according  to those
attributes, and to select stroke groups for manipulation. Group
services allow the user to collect strokes during or after their
creation.

      Automatic stroke grouping allows the user to group a set of
strokes into a single object as the strokes are being created.  For
example, strokes are collected into characters, characters into
words, and words into sentences.  The user can set spatial proximity
and temporal proximity parameters to affect the manner in which
strokes are collected.  The spatial parameters include relative and
bounded subparameters, which are mutually exclusive.  The relative
subparameter tells a grouping service to associate a current stroke
with previous strokes according to either a start-point-to-end-point
criterion, with two strokes being associated if the starting point of
the current stroke is within a pre-determined distance of the
endpoint of a previous stroke, or an any-point criterion, with two
strokes being associated if any point of the current stroke is within
a pre-determined distance of any point of a previous stroke.  The
bounded subparameter tells the grouping service to associate the
current stroke with a previous stroke if the two strokes fall within
either the bounding geometry of the current stroke or the application
window of the current stroke.  The bounding geometry of a stroke is
defined as the area within the smallest possible geometric shape of a
pre-determined type, such as a circle or rectangle, enclosing the
current group.  When strokes are associated, the bounding geometry
increases, if necessary, to enclose the new stroke.

      When a temporal proximity criterion is used, a current stroke
is associated with a previous stroke if the current stroke is begun
within a pre-determined time after the completion of the previous
stroke.  A user can simultaneously apply spatial and temporal
criteria.  Also, after he has completed a series of strokes, he can
finalize the grouping, so that new strokes are not associated with
the group.

      Another algorithm is used for automatic association of strokes.
First, a PEN_DOWN message is received from the...