Recognizing the cessation of motion of a pointing device on a display by comparing a group of signals to an anchor point

• US 5,404,458 A
• Filed: 02/24/1994
• Issued: 04/04/1995
• Est. Priority Date: 10/10/1991
• Status: Expired due to Term

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Zetts, John M.
• Primary Examiner(s): Lee, Thomas C.
• Assistant Examiner(s): MEKY, MOUSTAFA M
• Application Number:
  US08/201,147
• Time in Patent Office: 404 Days
• Field of Search: 395/140, 395/141, 395/142, 395/143, 395/147, 395/162, 345/145, 345/156, 345/157, 345/158, 345/159, 345/160, 345/161, 345/162, 345/163, 345/164, 345/167, 345/173, 345/179, 345/180, 364/927.5, 364/927.61, 364/929.12, 364/929.3
• US Class Current: 710/73
• CPC Class Codes: G06F 3/038 Control and interface arrangements therefor, e.g. drivers or device-embedded control circuitry
• CPC Class Codes: G06F 3/04883 for inputting data by handwriting, e.g. gesture or text

Abstract

A method and apparatus for efficiently distinguishing between different types of input signals simulated by a pointing device coupled to a multi-tasking computer system. The pointing device may be a stylus, finger or other device that moves across the surface of a touch screen or the like to generate positional information. Depending on the response of a delay timer, the motion of the pointing device is recognized by software application programs as input information either from a mouse or from a gesture or a handwriting input mode. If motion cessation across the screen is detected with a predetermined time-delay period, the system accepts the input information in a mouse-emulating mode. If motion is detected within the predetermined time-delay period, the timer is reset. Thus, the system overhead associated with managing the timer can be reduced because the timer is periodically reset and need not be reset after each movement of the pointing device as in the prior art. The periodic resetting can be based on intervals of n points generated by a moving pointing device, or n real-time units relative to a given point generated by the pointing device.

Claims

1. A method for reducing the processing time required to recognize the cessation of motion of a moving pointing device in an information processing system, the method comprising the steps of:

determining that a pointing device is located in operative proximity to a display screen, in said information processing system;

generating a series of delay timers having a predetermined rate, while said pointing device is located in said operative proximity to said display screen, in said information processing system;

accessing a predetermined timer divide rate value `n` from said information processing system, representing a predetermined plurality of `n` of coordinate point signals, in said information processing system;

receiving a first point signal for said pointing device with respect to said display screen, and buffering said first point signal in a memory as an anchor point and starting a delay timer, in said information processing system;

receiving a plurality of n-1 succeeding point signals for said pointing device with respect to said display screen, and buffering said plurality of n+1 signals, in a memory in said information processing system;

computing whether said pointing device has moved with respect to said display screen by comparing at least one of said buffered plurality of n-1 point signals with said buffered anchor point, in said information processing system;

if said computing step determines that said pointing device has moved, then receiving a second plurality of n succeeding coordinate point signals for said pointing device with respect to said display screen, and buffering a first of said second plurality of n signals as a new anchor point while restarting the delay timer, in said information processing system;

if said computing step determines that said pointing device has not moved, then outputting a first output signal indicating cessation of motion of said pointing device;

if said determining step determines that said pointing device is not located in said operative proximity to said display screen, then outputting a second output signal indicating that said pointing device has been removed from said operative proximity to said display screen.

2. The method as recited in claim 1, which further comprises the steps of:

identifying the pointing device as one among several possible pointing devices; and

setting, in accordance with the identified pointing device, said predetermined delay timer value.

3. The method as recited in claim 1, wherein the pointing device is a finger moving across a touch sensor, and further comprising the step of canceling said delay timer when the finger is lifted off the touch sensor.

4. The method as recited in claim 1, wherein the information processing system enters a mouse emulation mode in response to said first output signal.

5. The method as recited in claim 1, further comprising the step of entering a gesture recognition mode when said second output signal is outputted.

6. A method for reducing the processing time required to recognize the cessation of motion of a moving pointing device in an information processing system, the method comprising the steps of:

determining that a pointing device is located in operative proximity to a touch sensor controlling a display screen, in said information processing system;

generating a series of delay timers having a predetermined rate, while said pointing device is located in said operative proximity to said touch sensor, in said information processing system;

accessing a predetermined timer divide rate value `n` from said information processing system, representing a predetermined plurality of `n` of coordinate point signals, in said information processing system;

receiving a first point signal for said pointing device with respect to said touch sensor, and buffering said first point signal in a memory as an anchor point and starting a delay timer, in said information processing system;

receiving a plurality of n-1 succeeding coordinate point signals for said pointing device with respect to said touch sensor,

and buffering said plurality of n-1 signals, in said memory in said information processing system;

computing whether said pointing device has moved with respect to said touch sensor by comparing at least one of said buffered plurality of n-1 point signals with said buffered anchor point, in said information processing system;

if said computing step determines that said pointing device has moved, then receiving a second plurality of n succeeding coordinate point signals for said pointing device with respect to said touch sensor, and buffering a first of said second plurality of n signals as a new anchor point while restarting the delay timer, in said information processing system;

if said computing step determines that said pointing device has not moved, then outputting a first output signal indicating cessation of motion of said pointing device;

if said determining step determines that said pointing device is not located in said operative proximity to said touch sensor, then outputting a second output signal indicating that said pointing device has been removed from said operative proximity to said touch sensor.

7. The method as recited in claim 6, further comprising the step of identifying a type of said pointing device wherein said predetermined delay timer value is determined in accordance with the type identified.

8. The method recited in claim 6, wherein when motion of said pointing device has not been detected within a number of previous position points, said predetermined delay timer value is reduced in accordance with the number of previous position points.

9. The method recited in claim 6, wherein the system accepts information from said pointing device as gesture or character information in response to movement and removal of said pointing device from said touch sensor.

10. The method as recited in claim 6, further comprising the step of entering a gesture recognition mode when said second output signal is outputted.

11. A method for reducing the processing time required in a multi-tasking information processing system, to recognize the cessation of motion of a moving first pointing device that emulates a second pointing device in the system, the method comprising the steps of:

determining that a first pointing device is located in operative proximity to a display screen, in said information processing system;

generating a series of delay timers having a predetermined rate, while said pointing device is located in said operative proximity to said display screen, in said information processing system;

accessing a predetermined timer divide rate value `n` from said information processing system, representing a predetermined plurality of `n` of coordinate point signals, in said information processing system;

receiving a first point signal for said pointing device with respect to said display screen, and buffering said first point signal in a memory as an anchor point and starting a delay timer, in said information processing system;

receiving a plurality of n-1 succeeding point signals for said pointing device with respect to said display screen, and buffering said plurality of n-1 signals, in said memory in said information processing system;

computing whether said pointing device has moved with respect to said display screen by comparing at least one of said buffered plurality of n-1 point signals with said buffered anchor point, in said information processing system;

if said computing step determines that said pointing device has moved, then receiving a second plurality of n succeeding coordinate point signals for said pointing device with respect to said display screen, and buffering a first of said second plurality of n signals as a new anchor point while restarting the delay timer, in said information processing system;

if said computing step determines that said first pointing device has not moved, then outputting a first output signal indicating cessation of motion of said first pointing device and designating it as said second pointing device;

if said determining step determines that said first pointing device is not located in said operative proximity to said display screen, then outputting a second output signal indicating that said first pointing device has been removed from said operative proximity to said display screen.

12. A data processing system for reducing the processing time required to recognize the cessation of motion of a moving pointing device, comprising:

means for determining that a pointing device is located in operative proximity to a touch sensor controlling a display screen, in said data processing system;

means for generating a series of delay timers having a predetermined rate, while said pointing device is located in said operative proximity to said touch sensor, in said data processing system;

means for accessing a predetermined timer divide rate value `n` from said information processing system, representing a predetermined plurality of `n` of coordinate point signals, in said data processing system;

means for receiving a first point signal for said pointing device with respect to said touch sensor, and buffering said first point signal in a memory as an anchor point and starting a delay timer, in said data processing system;

said receiving means receiving a plurality of n-1 succeeding point signals for said pointing device with respect to said touch sensor, and buffering said plurality of n-1 signals, in a memory in said data processing system;

means for computing whether said pointing device has moved with respect to said touch sensor by comparing at least one of said buffered plurality of n-1 point signals with said buffered anchor point, in said data processing system;

if said computing step determines that said pointing device has moved, then receiving a second plurality of n succeeding coordinate point signals for said pointing device with respect to said touch sensor, and buffering a first of said second plurality of n signals as a new anchor point while restarting the delay timer, in said data processing system;

if said computing means determines that said pointing device has not moved, then said computing means outputs a first output signal indicating cessation of motion of said pointing device;

if said determining means determines that said pointing device is not located in said operative proximity to said touch sensor, then said computing means outputs a second output signal indicating that said pointing device has been removed from said operative proximity to said touch sensor.

13. The data processing system recited in claim 12, wherein the system accepts information from said pointing device as mouse input data in response to a recognition of motion cessation.

14. The data processing system recited in claim 12, wherein said touch sensor is a touch-sensitive display screen that displays information under control of said pointing device.

15. The data processing system recited in claim 12, wherein the system is a multi-tasking computer system that dedicates a single task to managing said computing by said computing means.

16. The data processing system recited in claim 12, wherein the system enters a gesture recognition mode when said second output signal is outputted.