MOTION COMPONENT DOMINANCE FACTORS FOR MOTION LOCKING OF TOUCH SENSOR DATA

• US 20160154529A1
• Filed: 01/26/2016
• Published: 06/02/2016
• Est. Priority Date: 01/04/2008
• Status: Abandoned Application

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Westerman, Wayne Carl
• Application Number:
  US15/006,987
• Publication Number:
  US 20160154529A1
• Time in Patent Office: Days
• CPC Class Codes: G06F 3/0418 for error correction or compensation, e.g. based on parallax, calibration or alignment
• CPC Class Codes: G06F 3/04883 for inputting data by handwriting, e.g. gesture or text
• CPC Class Codes: G06T 7/337 involving reference images or patches
• CPC Class Codes: G06V 10/421 by analysing segments intersecting the pattern

Abstract

An image jaggedness filter is disclosed that can be used to detect the presence of ungrounded objects such as water droplets or coins, and delay periodic baseline adjustments until these objects are no longer present. To do otherwise could produce inaccurate normalized baseline sensor output values. The application of a global baseline offset is also disclosed to quickly modify the sensor offset values to account for conditions such as rapid temperature changes. Background pixels not part of any touch regions can be used to detect changes to no-touch sensor output values and globally modify the sensor offset values accordingly. The use of motion dominance ratios and axis domination confidence values is also disclosed to improve the accuracy of locking onto dominant motion components as part of gesture recognition.

Claims

1. An apparatus for reconstructing a first image on a touch panel from a second image captured on the touch panel, the apparatus comprising:

scan logic couplable to the touch panel and capable of performing a scan of the touch panel so as to capture the second image; and

a processor coupled to the scan logic and capable of

aligning columns of image data in the second image with each other, and

aligning the column-aligned image data with a baseline value to reconstruct the first image.

2. The apparatus of claim 1, wherein aligning the columns of image data comprises calculating an offset for each column, the offset indicative of an amount of misalignment of the column with other columns.

3. The apparatus of claim 2, wherein the offset for each column comprises a previously computed offset value.

4. The apparatus of claim 1, wherein aligning the column-aligned image data comprises calculating a global offset for the column-aligned image data, the offset indicative of an amount of alignment needed to reach the baseline value.

5. The apparatus of claim 1, wherein aligning the column-aligned image data with the baseline value comprises computing an average value of a plurality of background pixels.

6. The apparatus of claim 5, wherein the plurality of background pixels belong to an untouched region of the touch panel.

7. The apparatus of claim 5, the processor further capable of decaying the global baseline value over time.

8. The apparatus of claim 7, the processor further capable of adjusting a local baseline value to compensate for the decaying of the global baseline value over time.

9. The apparatus of claim 8, wherein the baseline value comprises a sum of the local baseline value and the global baseline value.

10. The apparatus of claim 8, wherein a maximum adjustment step size of the global baseline value is larger than a maximum adjustment step size of the local baseline value.

11. The apparatus device of claim 1, the apparatus comprising at least one of a computing device, a media player, or a mobile telephone.

12. A method for reconstructing a first image from a second image comprising:

capturing the second image on a touch sensitive device;

aligning columns of image data in the second image with each other; and

aligning the column-aligned image data with a baseline value to reconstruct the first image.

13. The method of claim 12, wherein aligning columns of image data comprises calculating an offset for each column, the offset indicative of an amount of misalignment of the column with the other columns.

14. The method of claim 13, wherein the offset for each column comprises a previously computed offset value.

15. The method claim 12, wherein aligning the column-aligned image data comprises calculating a global offset for the column-aligned image data, the offset indicative of an amount of alignment needed to reach the baseline value.

16. The method of claim 12, wherein aligning the column-aligned image data with the baseline value comprises computing an average value of a plurality of background pixels.

17. The method of claim 16, wherein the plurality of background pixels belong to an untouched region of the touch sensitive device.

18. The method of claim 16, further comprising decaying the global baseline value over time.

19. The method of claim 18, further comprising adjusting a local baseline value to compensate for the decaying of the global baseline value over time.

20. The method of claim 19, wherein the baseline value comprises a sum of the local baseline value and the global baseline value.

21. The method of claim 19, wherein a maximum adjustment step size of the global baseline value is larger than a maximum adjustment step size of the local baseline value.

22. A touch sensitive device comprising:

a touch panel capable of sensing a proximate object;

scan logic couplable to the touch panel and capable of performing a scan of the touch panel so as to capture a first touch image; and

a processor capable of reconstructing a second touch image from the first touch image, the reconstructing including

calculating first alignments for portions of the first touch image, each portion having a different first alignment,

aligning the portions with each other according to the first alignments to form an aligned first image,

calculating a second alignment for the aligned first image, and

aligning the aligned first image according to the second alignment to meet a baseline value so as to form the reconstructed second touch image.

23. The touch sensitive device of claim 22, the touch sensitive device comprising at least one of a computing device, a media player, or a mobile telephone.