Bounding box gesture recognition on a touch detecting interactive display
A method and apparatus for identifying user gestures to control an interactive display identifies gestures based on a bounding box enclosing points at which a user contacts a touch sensor corresponding with the display surface and permits use of inexpensive and highly reliable grid-based touch sensors that provide a bounding box to describe contact information. In identifying gestures, position, motion, shape, and deformation of the bounding box may be considered. Center, width, height, aspect ratio, length and orientation of the bounding box diagonal may be determined. A stretch factor, defined as the maximum of the ratio of the height of the bounding box to the width of the bounding box and the ratio of the width of the bounding box to the height of the bounding box, may also be computed. Gestures may be identified based on the changes in time of these characteristics and quantities.
1. In an interactive display, a method for identifying a specific user gesture comprising the steps of:
displaying imagery on an imaging surface;
responsive to a user contacting a touch sensor, detecting a plurality of contact locations at which the user contacts the touch sensor to control said display;
responsive to a determination that a motion of a bounding box enclosing at least two of said plurality of contact locations exceeds a predetermined motion threshold and that deformation of said bounding box is less than a predetermined deformation threshold, said determination that said motion of the bounding box enclosing said at least two of said plurality of contact locations exceeds said predetermined motion threshold and that deformation of said bounding box is less than said predetermined deformation threshold being based on rates of change of particular parameters of said bounding box, identifying said specific user gesture as a pan gesture;
associating said specific user gesture with a display command; and
executing said display command to alter the display of said imagery.
2. The method of claim 1 , wherein said display command affects a translation of said imagery.
3. An interactive display comprising:
means for displaying imagery on an imaging surface;
a touch sensor corresponding to said imaging surface;
means for detecting, responsive to a user contacting said touch sensor, a plurality of contact locations at which the user contacts said touch sensor to control said display;
means for identifying a pan gesture, comprising:
means for determining if a motion of a bounding box surrounding at least two of said contact locations is greater than a predetermined motion threshold; and
means for determining if a deformation of said bounding box is less than a predetermined deformation threshold;
wherein said means for determining if said motion of the bounding box surrounding at least two of said contact locations is greater than the predetermined motion threshold and said means for determining if said deformation of said bounding box is less than a predetermined deformation threshold are configured to determine, based on rates of change of particular parameters of said bounding box, if said motion of the bounding box surrounding at least two of said contact locations is greater than said predetermined motion threshold and if said deformation of said bounding box is less than a predetermined deformation threshold;
means for associating said pan gesture with a corresponding display command; and
means for executing said display command to alter the display of said imagery.
4. An interactive display comprising:
means for displaying imagery on an imaging surface;
a touch sensor corresponding to said imaging surface;
means for detecting, responsive to a user contact with the touch sensor, a plurality of contact locations at which the user contacts said touch sensor to control said display;
means for identifying a specific user gesture among a plurality of user gestures based on a bounding box surrounding at least two of said contact locations comprising:
means for identifying a pan gesture, wherein said means for identifying a pan gesture comprises:
means for determining if a motion of said bounding box is greater than a predetermined motion threshold; and
means for determining if a deformation of said bounding box is less than a predetermined deformation threshold;
wherein said means for determining if said motion of said bounding box is greater than said predetermined motion threshold and said means for determining if said deformation of said bounding box is less than said predetermined deformation threshold are configured to determine, based on rates of change of particular parameters of said bounding box, if said motion of said bounding box is greater than said predetermined motion threshold and if said deformation of said bounding box is less than said predetermined deformation threshold;
means for identifying a zoom gesture; and
means for identifying a rotate gesture;
means for associating said specific user gesture with a corresponding display command; and
means for executing said display command to alter the display of said imagery.
5. A non-transitory machine-readable medium comprising instructions which, when executed by a machine, cause the machine to perform operations comprising:
displaying imagery on an imaging surface of an interactive display;
responsive to a user contacting a touch sensor associated with the imaging surface to make a specific user gesture, detecting a plurality of contact locations at which the user contacts the touch sensor to control said display;
responsive to a determination that a motion of a bounding box enclosing at least two of said plurality of contact locations exceeds a predetermined motion threshold and that deformation of said bounding box is less than a predetermined deformation threshold, said determination that said motion of the bounding box enclosing said at least two of said plurality of contact locations exceeds said predetermined motion threshold and that deformation of said bounding box is less than said predetermined deformation threshold being based on rates of change of particular parameters of said bounding box, identifying said specific user gesture as a pan gesture;
associating said specific user gesture with a display command; and
executing said display command to alter the display of said imagery.
6. An interactive display comprising:
an imaging surface for displaying imagery;
a touch sensor associated with the imaging surface, the touch sensor being configured to
detect a plurality of contact locations at which a user contacts the touch sensor to control said interactive display, and
identify said specific user gesture as a pan gesture responsive to a determination that a motion of a bounding box enclosing at least two of said plurality of contact locations exceeds a predetermined motion threshold and that deformation of said bounding box is less than a predetermined deformation threshold, said determination that said motion of the bounding box enclosing said at least two of said plurality of contact locations exceeds said predetermined motion threshold and that deformation of said bounding box is less than said predetermined deformation threshold being based on rates of change of particular parameters of said bounding box; and
a processor configured to associate said specific user gesture with a display command and to execute said display command to alter the display of said imagery.
7. An interactive display comprising:
means for displaying imagery on an imaging surface of an interactive display;
means for detecting a plurality of contact locations at which a user contacts a touch sensor to control said means for displaying, responsive to the user contacting the touch sensor to make a specific user gesture;
means for identifying said specific user gesture as a pan gesture responsive to a determination that a motion of a bounding box enclosing at least two of said plurality of contact locations exceeds a predetermined motion threshold and that deformation of said bounding box is less than a predetermined deformation threshold, said determination that said motion of the bounding box enclosing said at least two of said plurality of contact locations exceeds said predetermined motion threshold and that deformation of said bounding box is less than said predetermined deformation threshold being based on rates of change of particular parameters of said bounding box;
means for associating said specific user gesture with a display command; and
means for executing said display command to alter the display of said imagery.