Multi-finger detection and component resolution

• US 8,913,019 B2
• Filed: 07/14/2011
• Issued: 12/16/2014
• Est. Priority Date: 07/14/2011
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Zhao, Weidong, Stevens, David A., Uzelac, Aleksandar
• Primary Examiner(s): LAMB, CHRISTOPHER RAY
• Application Number:
  US13/183,377
• Publication Number:
  US 20130016045A1
• Time in Patent Office: 1,251 Days
• Field of Search: None
• US Class Current: 345/173
• CPC Class Codes: G06F 2203/04104 Multi-touch detection in digitiser, i.e. details about the simultaneous detection of a plurality of touching locations, e.g. multiple fingers or pen and finger
• CPC Class Codes: G06F 3/04186 Touch location disambiguation
• CPC Class Codes: G06F 3/04883 for inputting data by handwriting, e.g. gesture or text

Abstract

In embodiments of multi-finger detection and component resolution, touch input sensor data is recognized as a component of a multi-finger gesture on a touch-screen display. An ellipse is determined that approximately encompasses the component, and the ellipse has a primary axis and a secondary axis that are orthogonal. A distribution is then generated that projects sensor data elements from the primary axis based on detected intensity of the touch input sensor data. A histogram function can then be generated based on the distribution, where the histogram function indicates individual contacts of the component and separation of the individual contacts.

Claims

1. A method, comprising:

recognizing touch input sensor data as a component of a multi-finger gesture on a touch-screen display;

determining an ellipse that approximately encompasses the component, the ellipse having a primary axis and a secondary axis that are orthogonal;

generating a distribution that projects sensor data elements from the primary axis based on detected intensity of the touch input sensor data; and

generating a histogram function based on the distribution, using a ratio of a weighting function which reduces contribution from a location with a peak value and a normalization function which neutralizes contribution from a neighbor location, the ratio being the weighting function which reduces contribution from a location with a peak value divided by the normalization function which neutralizes contribution from a neighbor location, the histogram function indicating individual contacts of the component and separation of the individual contacts.

2. A method as recited in claim 1, further comprising associating each individual contact of the component with a different finger input of the multi-finger gesture.

3. A method as recited in claim 1, wherein histogram function high points indicate the individual contacts of the component, and a histogram function low point indicates the separation of the individual contacts of the component.

4. A method as recited in claim 3, further comprising performing a retrace of the histogram function to confirm the histogram function high points and to eliminate a false indication of an individual contact.

5. A method as recited in claim 1, wherein:

the component is represented as a sensor map, which is generated as a two dimensional array of the sensor data elements that correlate to the detected intensity of the multi-finger gesture on the touch-screen display; and

a stronger sensor signal of the touch input sensor data indicates more contact with a sensor data element in the sensor map.

6. A method as recited in claim 5, further comprising modeling the sensor map as a Gaussian distribution, and wherein the ellipse that approximately encompasses the component is determined from the Gaussian distribution.

7. A method as recited in claim 1, further comprising:

separating the individual contacts of the component; and

determining an individual ellipse for each individual contact to map each of the individual contacts for association with the different finger inputs of the multi-finger gesture.

8. A computing device, comprising:

a touch-screen display;

a touch input module configured to recognize touch input sensor data as a component of a multi-finger gesture on the touch-screen display;

at least a memory and a processor to implement a component resolution service configured to;

determine an ellipse that approximately encompasses the component, the ellipse having a primary axis and a secondary axis that are orthogonal;

generate a distribution that projects sensor data elements from the primary axis based on detected intensity of the touch input sensor data; and

generate a histogram function based on the distribution, using a ratio of a weighting function which reduces contribution from a location with a peak value and a normalization function which neutralizes contribution from a neighbor location, the ratio being the weighting function which reduces contribution from a location with a peak value divided by the normalization function which neutralizes contribution from a neighbor location, the histogram function indicating individual contacts of the component and separation of the individual contacts.

9. A computing device as recited in claim 8, wherein the component resolution service is further configured to associate each individual contact of the component with a different finger input of the multi-finger gesture.

10. A computing device as recited in claim 8, wherein histogram function high points indicate the individual contacts of the component, and a histogram function low point indicates the separation of the individual contacts of the component.

11. A computing device as recited in claim 10, wherein the component resolution service is further configured to perform a retrace of the histogram function to confirm the histogram function high points and to eliminate a false indication of an individual contact.

12. A computing device as recited in claim 8, wherein:

the component is represented as a sensor map, which is generated as a two dimensional array of the sensor data elements that correlate to the detected intensity of the multi-finger gesture on the touch-screen display; and

a stronger sensor signal of the touch input sensor data indicates more contact with a sensor data element in the sensor map.

13. A computing device as recited in claim 12, wherein the component resolution service is further configured to model the sensor map as a Gaussian distribution, and wherein the ellipse that approximately encompasses the component is determined from the Gaussian distribution.

14. A computing device as recited in claim 8, wherein the component resolution service is further configured to:

separate the individual contacts of the component; and

determine an individual ellipse for each individual contact to map each of the individual contacts for association with the different finger inputs of the multi-finger gesture.

15. One or more computer-readable storage media devices comprising instructions that are executable and, responsive to executing the instructions, a computing device:

recognizes touch input sensor data as a component of a multi-finger gesture on a touch-screen display;

determines an ellipse that approximately encompasses the component, the ellipse having a primary axis and a secondary axis that are orthogonal;

generates a distribution that projects sensor data elements from the primary axis based on detected intensity of the touch input sensor data; and

generates a histogram function based on the distribution, using a ratio of a weighting function which reduces contribution from a location with a peak value and a normalization function which neutralizes contribution from a neighbor location, the ratio being the weighting function which reduces contribution from a location with a peak value divided by the normalization function which neutralizes contribution from a neighbor location, the histogram function indicating individual contacts of the component and separation of the individual contacts.

16. One or more computer-readable storage media devices as recited in claim 15, further comprising additional instructions that are executable and, responsive to executing the additional instructions, the computing device associates each individual contact of the component with a different finger input of the multi finger gesture.

17. One or more computer-readable storage media devices as recited in claim 15, further comprising additional instructions that are executable and, responsive to executing the additional instructions, the computing device generates the histogram function to include high points that indicate the individual contacts of the component, and to include histogram function low points that indicate the separation of the individual contacts of the component.

18. One or more computer-readable storage media devices as recited in claim 17, further comprising additional instructions that are executable and, responsive to executing the additional instructions, the computing device performs a retrace of the histogram function to confirm the histogram function high points and to eliminate a false indication of an individual contact.

19. One or more computer-readable storage media devices as recited in claim 15, further comprising additional instructions that are executable and, responsive to executing the additional instructions, the computing device:

separates the individual contacts of the component; and

determines an individual ellipse for each individual contact to map each of the individual contacts for association with the different finger inputs of the multi-finger gesture.

20. One or more computer-readable storage media devices as recited in claim 15, further comprising additional instructions that are executable and, responsive to executing the additional instructions, the computing device models a sensor map as a Gaussian distribution, wherein:

the ellipse that approximately encompasses the component is determined from the Gaussian distribution;

the component is represented as the sensor map, which is generated as a two dimensional array of the sensor data elements that correlate to the detected intensity of the multi-finger gesture on the touch-screen display; and

a stronger sensor signal of the touch input sensor data indicates more contact with a sensor data element in the sensor map.