IRREGULAR INPUT IDENTIFICATION

• US 20080158146A1
• Filed: 01/03/2007
• Published: 07/03/2008
• Est. Priority Date: 01/03/2007
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Computer Incorporated (Apple Inc.)
• Inventors: Westerman, Wayne Carl
• Granted Patent: US 8,269,727 B2
• Time in Patent Office: Days
• US Class Current: 345/156
• CPC Class Codes: G06F 2203/04101 2.5D-digitiser, i.e. digitiser detecting the X/Y position of the input means, finger or stylus, also when it does not touch, but is proximate to the digitiser's interaction surface and also measures the distance of the input means within a short range in the Z direction, possibly with a separate measurement setup
• 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 3/04166 Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally G06F3/04184
• CPC Class Codes: G06F 3/04182 Filtering of noise external to the device and not generated by digitiser components
• CPC Class Codes: G06F 3/04186 Touch location disambiguation
• CPC Class Codes: G06F 3/044 by capacitive means
• CPC Class Codes: G06F 3/0488 using a touch-screen or digitiser, e.g. input of commands through traced gestures
• CPC Class Codes: G06T 5/20 using local operators
• CPC Class Codes: G06T 5/70 Denoising; Smoothing
• CPC Class Codes: G06T 7/11 Region-based segmentation
• CPC Class Codes: G06T 7/41 based on statistical description of texture
• CPC Class Codes: G06V 40/107 Static hand or arm

Abstract

Techniques for identifying irregular objects in contact with, or in close proximity to, a touch-surface are described. An irregularity measure is determined based on the regions intrinsic characteristics (e.g., energy content) rather than on the shape (or pattern) of the pixels within the region.

Claims

1. A method to process a proximity image, comprising:

obtaining a dispersion image, the dispersion image having a plurality of pixels;

determining an irregularity measure value for the dispersion image;

controlling an operation of a multi-touch touch-surface device if the irregularity measure value is above a specified threshold.

2. The method of claim 1, wherein the act of obtaining comprises:

receiving a proximity image;

high-pass filtering the proximity image to generate a filtered proximity image; and

generating the dispersion image by subtracting the filtered proximity image from the proximity image

3. The method of claim 1, wherein the act of determining comprises:

determining a total energy value for the dispersion image;

determining a spatial energy value for the dispersion image;

determining a peak energy value for the dispersion image; and

determining an irregularity measure value for the dispersion image by dividing the difference between the spatial energy value and the peak energy value by the total energy value.

4. The method of claim 1, wherein the specified threshold comprises a constant function.

5. The method of claim 1, wherein the specified threshold comprises a linear function.

6. The method of claim 1, wherein the specified threshold comprises a non-linear function.

7. The method of claim 1, wherein the specified threshold comprises two or more linear functions.

8. The method of claim 1, wherein the operation of a touch-surface device comprises causing the touch-surface device to obtain baseline touch-surface sensor values.

9. The method of claim 1, wherein the operation of a touch-surface device comprises determining a touch-surface sensor sampling frequency to ignore during touch-surface device operations.

10. The method of claim 1, wherein the operation of a touch-surface device comprises causing the multi-touch touch-surface device to enter into a low-power state.

11. The method of claim 1, wherein the operation of a multi-touch touch-surface device comprises causing the multi-touch touch-surface device to exit a low-power state.

12. The method of claim 1, wherein the multi-touch touch-surface device comprises one of the devices selected from the group of tablet computer system, notebook computer system, portable music player, portable video player, personal digital assistant and mobile telephone.

13. A program storage device, readable by a programmable control device, comprising instructions stored thereon for causing the programmable control device to perform the method of claim 1.

14. A portable electronic device, comprising:

a multi-touch input touch-surface component;

means for receiving a proximity image from the multi-touch input touch-surface; and

processing means for performing acts in accordance with claim 1.

15. The device in accordance with claim 14, wherein the portable electronic device comprises a mobile telephone.

16. The device in accordance with claim 14, wherein the portable electronic device comprises is selected from the group consisting of a tablet computer system, a hand-held computer system, a portable music player system, and a portable video player system.

17. A method to identify an irregular input source to a multi-touch touch-surface device, comprising:

obtaining a proximity image;

generating a dispersion image from the proximity image;

segmenting the proximity image to identify a plurality of patches;

determining an irregularity measure value for each of the plurality of patches based on the proximity image and dispersion image;

identifying one of the plurality of patches as being associated with an irregular object if the irregularity measure value of the one patch is above a specified threshold; and

controlling an operation of a multi-touch touch-surface device based on the identification of the irregular object.

18. The method of claim 17, wherein the act of obtaining further comprises high-pass filtering the proximity image to generate a filtered proximity image.

19. The method of claim 18, wherein the act of generating comprises subtracting the filtered proximity image from the proximity image.

20. The method of claim 17, wherein the act of determining comprises:

determining a total energy value for each of the plurality of patches;

determining a spatial energy value for each of the plurality of patches;

determining a peak energy value for each of the plurality of patches; and

determining an irregularity measure value for each of the plurality of patches by dividing the difference between the peak energy value for each patch from and the spatial energy value for each patch by the total energy value for each patch.

21. The method of claim 17, wherein the specified threshold comprises a constant function.

22. The method of claim 17, wherein the specified threshold comprises a linear function.

23. The method of claim 17, wherein the specified threshold comprises a non-linear function.

24. The method of claim 17, wherein the specified threshold comprises two or more linear functions.

25. The method of claim 17, wherein the irregular patch comprises a patch formed by an ear.

26. The method of claim 17, wherein the act of identifying comprises distinguishing a patch associated with an irregular object from a patch associated with a large object based on the irregularity measure value for the patch associated with the irregular object being greater than the specified threshold and the irregularity measure value for the patch associated with the large object being less than the specified threshold.

27. The method of claim 26, wherein the large object comprises a cheek, a chest or a leg.

28. The method of claim 26, wherein the irregular object comprises an ear, coin, or a key.

29. The method of claim 17, wherein the act of identifying comprises distinguishing a patch associated with an irregular object from a patch associated with a small regular based on the irregularity measure value for the patch associated with the irregular object being greater than the specified threshold and the irregularity measure value for the patch associated with the small regular object being less than the specified threshold.

30. The method of claim 26, wherein the small regular object comprises a finger or a thumb.

31. The method of claim 17, wherein the multi-touch touch-surface device comprises one of the devices selected from the group of tablet computer system, notebook computer system, portable music player, portable video player, personal digital assistant and mobile telephone.

32. A program storage device, readable by a programmable control device, comprising instructions stored thereon for causing the programmable control device to perform the method of claim 17.

33. A portable electronic device, comprising:

a multi-touch input touch-surface component;

means for receiving a proximity image from the multi-touch input touch-surface; and

processing means for performing acts in accordance with claim 17.

34. The device in accordance with claim 33, wherein the portable electronic device comprises a tablet computer system.

35. The device in accordance with claim 33, wherein the portable electronic device comprises a hand-held computer system.

36. The device in accordance with claim 33, wherein the portable electronic device comprises a mobile telephone.

37. The device in accordance with claim 33, wherein the portable electronic device comprises a portable music player system.

38. The device in accordance with claim 33, wherein the portable electronic device comprises a portable video player system.