Location based object classification

1. A processing system for a capacitive sensing device, comprising:

a processor configured to execute instructions to perform operations comprising:

a sensor module for performing capacitive sensing in a sensing region using a plurality of sensor electrodes, the sensing region comprising a first sub-region, a second sub-region, and a third sub-region; and

a determination module for:

detecting a first input object in the sensing region upon an initial contact of the first input object in the sensing region,

determining first positional information of the first input object,

determining, from the first positional information, that the first input object is located in the second sub-region of the sensing region,

determining a length of the first input object, the length of the first input object being a size of the first input object along a first axis,

determining a distance between the first input object and the third sub-region,

determining, based on the first input object being in the second sub-region, a length threshold matching the distance between the first input object and the third sub-region,

wherein, in the second sub-region, the length threshold varies according to the distance to the third sub-region,

responsive to the first input object being located in the second sub-region of the sensing region and the length of the first input object being greater than the length threshold, suppressing reporting of the first input object.

2. The processing system of claim 1 , wherein the length threshold is held constant in the third sub-region of the sensing region.

3. The processing system of claim 1 , wherein the second sub-region of the sensing region substantially surrounds the first sub-region.

4. The processing system of claim 1 , wherein the determination module is further for:

determining that a second input object is in the first sub-region when the first input object is determined to be in the second sub-region; and

reporting the second input object while reporting of the first input object is suppressed.

5. The processing system of claim 1 , wherein the third sub-region of the sensing region substantially surrounds the second sub-region.

6. The processing system of claim 5 , wherein the determination module is further for:

determining that a location of a second input object is in at least one selected from a group consisting of the first sub-region and the third sub-region;

suppressing reporting of all input objects in the second sub-region based the location of the second input object.

7. The processing system of claim 5 , wherein the determination module is further for:

determining, for a first time, that a location of a plurality of input objects is in the third sub-region,

determining, for the first time, that a location of a second input object is in at least one selected from a group consisting of the first sub-region and the second sub-region, wherein the second input object is not in the plurality of input objects, and

suppressing, for the first time, reporting of the plurality of input objects while reporting the second input object based on the location of the plurality of input objects and the location of the second input object.

8. The processing system of claim 7 , wherein the determination module is further for:

determining, for a second time, that the plurality of input objects remain in the third sub-region,

determining, for the second time, that the second input object moved to the third sub-region, and

suppressing, for the second time, reporting of the plurality of input objects while reporting the second input object based on the location of the plurality of input objects at the first time and the second time and the location of the second input object at the first time.

9. The processing system of claim 1 , wherein the determination module is further for:

determining that a second input object is in the first sub-region;

determining that the second input object is a palm; and

suppressing reporting of all input objects in the sensing region based the second input object being determined to be a palm.

10. The processing system of claim 1 , wherein the determination module is further for:

detecting a second input object in the sensing region,

determining, from second positional information, that the second input object is located in the first sub-region of the sensing region,

responsive to the second input object being located in the first sub-region, reporting the second input object,

detecting a third input object in the sensing region,

determining, from third positional information, that the third input object is located in the third sub-region of the sensing region,

determining the length of the third input object, the length of the third input object being a size of the third input object along the first axis,

responsive to the third input object being located in the third sub-region of the sensing region and the length being greater than the length threshold, suppressing reporting of the third input object, wherein the length threshold is constant in the third sub-region,

wherein the second sub-region of the sensing region substantially surrounds the first sub-region and the third sub-region of the sensing region substantially surrounds the second sub-region, and

wherein the first sub-region is less suppressive of input objects than the second sub-region and the second sub-region is less suppressive of input objects than the third sub-region.

11. An input device comprising:

an array of sensor electrodes configured to sense input objects in a sensing region of the input device, the sensing region comprising a first sub-region, a second sub-region, and a third sub-region; and

a processing system configured to:

detect a first input object in the sensing region upon an initial contact of the first input object in the sensing region,

determine first positional information of the first input object,

determine, from the first positional information, that the first input object is located in the second sub-region of the sensing region,

determine a length of the first input object, the length of the first input object being a size of the first input object along a first axis,

determine a distance between the first input object and the third sub-region,

determine, based on the first input object being in the second sub-region, a length threshold matching the distance between the first input object and the third sub-region,

wherein, in the second sub-region, the length threshold varies according to the distance to the third sub-region,

responsive to the first input object being located in the second sub-region of the sensing region and the length of the first input object being greater than the length threshold, suppress reporting of the first input object.

12. The input device of claim 11 , wherein the length threshold is held constant in the third sub-region of sensing region.

13. The input device of claim 11 , wherein the second sub-region of the sensing region substantially surrounds the first sub-region.

14. The input device of claim 11 , wherein the processing system is further configured to:

determine that a second input object is in the first sub-region when the first input object is determined to be in the second sub-region; and

report the second input object while reporting of the first input object is suppressed.

15. The input device of claim 11 , wherein the third sub-region of the sensing region being substantially surrounds the second sub-region.

16. The input device of claim 11 , wherein the processing system is further configured to:

detect a second input object in the sensing region,

determine, from second positional information, that the second input object is located in the first sub-region of the sensing region,

responsive to the second input object being located in the first sub-region, report the second input object,

detect a third input object in the sensing region,

determine, from third positional information, that the third input object is located in the third sub-region of the sensing region,

determine the length of the third input object, the length of the third input object being a size of the third input object along the first axis,

responsive to the third input object being located in the third sub-region of the sensing region and the length being greater than the length threshold, suppress reporting of the third input object, wherein the length threshold is constant in the third sub-region,

wherein the second sub-region of the sensing region substantially surrounds the first sub-region and the third sub-region of the sensing region substantially surrounds the second sub-region, and

wherein the first sub-region is less suppressive of input objects than the second sub-region and the second sub-region is less suppressive of input objects than the third sub-region.

17. A method for capacitive sensing comprising:

detecting a first input object in a sensing region upon an initial contact of the first input object in the sensing region, the sensing region comprising a first sub-region, a second sub-region, and a third sub-region;

determining first positional information of the first input object;

determining, from the first positional information, that the first input object is located in the second sub-region of the sensing region;

determining a length of the first input object, the length of the first input object being a size of the first input object along a first axis;

determining a distance between the first input object and the third sub-region, determining, based on the first input object being in the second sub-region, a length threshold matching the distance between the first input object and the third sub-region,

wherein, in the second sub-region, the length threshold varies according to the distance to the third sub-region,

responsive to the first input object being located in the second sub-region of the sensing region and the length of the first input object being greater than the length threshold, suppressing reporting of the first input object.

18. The method of claim 17 , further comprising:

determining that a second input object is in the first sub-region when the first input object is determined to be in the second sub-region; and

reporting the second input object while reporting of the first input object is suppressed.

19. The method of claim 17 , further comprising:

detecting a second input object in the sensing region,

determining, from second positional information, that the second input object is located in the first sub-region of the sensing region,

responsive to the second input object being located in the first sub-region, reporting the second input object,

detecting a third input object in the sensing region,

determining, from third positional information, that the third input object is located in the third sub-region of the sensing region,

determining the length of the third input object, the length of the third input object being a size of the third input object along the first axis,

responsive to the third input object being located in the third sub-region of the sensing region and the length being greater than the length threshold, suppressing reporting of the third input object, wherein the length threshold is constant in the third sub-region,

wherein the second sub-region of the sensing region substantially surrounds the first sub-region and the third sub-region of the sensing region substantially surrounds the second sub-region, and

wherein the first sub-region is less suppressive of input objects than the second sub-region and the second sub-region is less suppressive of input objects than the third sub-region.