METHOD TO PARAMETERIZE AND RECOGNIZE CIRCULAR GESTURES ON TOUCH SENSITIVE SURFACES

• US 20120056821A1
• Filed: 09/07/2010
• Published: 03/08/2012
• Est. Priority Date: 09/07/2010
• Status: Active Grant

• Current Assignee: STMicroelectronics Asia Pacific Pte Limited (STMicroelectronics NV)
• Original Assignee: STMicroelectronics Asia Pacific Pte Limited (STMicroelectronics NV)
• Inventors: Goh, Hup-Peng
• Granted Patent: US 8,754,858 B2
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G06F 3/041661 using detection at multiple resolutions, e.g. coarse and fine scanning; using detection within a limited area, e.g. object tracking window
• CPC Class Codes: G06F 3/04883 for inputting data by handwriting, e.g. gesture or text

Abstract

A method to parameterize and recognize circular gestures on touch sensitive surfaces includes dividing the touch sensitive surface into four quadrants, detecting a transition from a first quadrant into a second quadrant, time-stamping and tracking each detected quadrant transition, and computing the time between quadrant transitions so that the circular speed and direction of the circular gestures on the touch sensitive surface can be detected. The detected direction can be either a clockwise or a counter-clockwise direction.

Claims

1. A method to parameterize and recognize circular gestures on touch sensitive surfaces comprising:

dividing the touch sensitive surface into four quadrants;

detecting a transition from a first quadrant into a second quadrant;

time-stamping and tracking each detected quadrant transition; and

computing the time between quadrant transitions so that the circular speed and direction of the circular gestures on the touch sensitive surface can be detected.

2. The method of claim 1 wherein the direction comprises a clockwise direction.

3. The method of claim 1 wherein the direction comprises a counter-clockwise direction.

4. The method of claim 1 further comprising classification of the four quadrants.

5. The method of claim 4 wherein each touch point (X, Y) across time is grouped in a respective quadrant depending on the changes in the current X and Y positions in a current touch frame with respect to a previous frame.

6. The method of claim 5 wherein a tracking touch point is classified in Quadrant1 (Q1) when a current Y coordinate is less than a previous Y coordinate and a current X coordinate is greater than a previous X coordinate.

7. The method of claim 5 wherein a tracking touch point is classified in Quadrant2 (Q2) when a current Y coordinate is greater than a previous Y coordinate and a current X coordinate is greater than a previous X coordinate.

8. The method of claim 5 wherein a tracking touch point is classified in Quadrant3 (Q3) when a current Y coordinate is greater than a previous Y coordinate and a current X coordinate is less than a previous X coordinate.

9. The method of claim 5 wherein a tracking touch point is classified in Quadrant4 (Q4) when a current Y coordinate is less than a previous Y coordinate and a current X coordinate is less than a previous X coordinate.

10. The method of claim 1 wherein each tracked touch point is monitored for quadrant transitions, and a clockwise touch point movement is recognized by a sequence of increasing quadrant numbers.

11. The method of claim 1 wherein each tracked touch point is monitored for quadrant transitions, and a counter-clockwise touch point movement is recognized by a sequence of decreasing quadrant numbers.

12. The method of claim 1 further comprising providing a quadrant transition value.

13. The method of claim 12 wherein a quadrant transition value of 00 comprises a no quadrant transition value.

14. The method of claim 12 wherein a quadrant transition value of 01 comprises a clockwise quadrant transition value.

15. The method of claim 12 wherein a quadrant transition value of 10 comprises a counter-clockwise quadrant transition value.

16. The method of claim 1 further comprising providing a timestamp value.

17. The method of claim 16 wherein the timestamp value is provided when there is a quadrant transition.

18. The method of claim 16 wherein the timestamp value measures the time lapsed between a current and a previous quadrant transition.

19. A method for circular gesture recognition associated with a touch-screen comprising:

a timer is loaded with a chosen number of ticks to countdown to zero;

the timer is reloaded whenever it reaches zero or when there is a change in direction of a quadrant transition;

a transition counter increments on every quadrant transition;

the counter is cleared on timer load or reload; and

if the number of quadrant transitions in the same direction is equal to or above the criteria threshold when the timer reaches zero, a circular gesture is recognized.

20. A method for circular gesture recognition associated with a touch-screen comprising:

a transition counter increments on every quadrant transition;

the counter is cleared when a chosen fixed number of same direction quadrant transitions is reached or when there is a direction change before the chosen number of transitions is reached;

a timestamp is accumulated for every quadrant transition;

the timestamp accumulation is cleared when the transition counter is cleared; and

if the accumulated time is less than the threshold time when the transition counter reaches the chosen number of quadrant transitions, a circular gesture is recognized.

21. The method of claim 20 further comprising performing the method for each tracking touch identification on the touch-screen of a multi-touch system.