Automatic customization of keypad key appearance

1. A method of adjusting a size of one or more keys of a soft keyboard presented on a display of a computing device, comprising:

calculating, by a processor of the computing device, a dimension of a finger feature of a finger of a user of the computing device from an image of the finger captured in an image frame of a camera of the computing device based on parameters of the camera of the computing device comprising:

calculating an object distance of the finger of the user from a lens of the camera based on at least a focal length of the camera and an image distance of the camera comprising:

focusing the camera of the computing device on the finger of the user;

determining the focal length of the camera when focused on the finger; and

calculating the object distance from the camera to the finger based upon the determined focal length; and

calculating, by the processor, the dimension of the finger feature based on at least the object distance of the finger of the user from the lens of the camera, a width of a camera sensor of the camera in pixels, a width of the finger feature in pixels, an angle of a field of view of the camera;

determining, by the processor, a size of the finger of the user based on the calculated dimension of the finger feature; and

adjusting, by the processor, the size of one or more keys of the soft keyboard based on the determined size of the finger of the user.

2. The method of claim 1 , further comprising:

searching, by the processor, the image frame of the camera to find the finger of the user; and

identifying, by the processor, the finger feature in response to finding the finger of the user in the image frame.

3. The method of claim 1 , wherein determining, by the processor, the size of the finger of the user based on the calculated dimension of the finger feature comprises approximating the size of the finger of the user based on an outline of the finger of the user and the calculated dimension of the finger feature.

4. The method of claim 1 , wherein adjusting, by the processor, the size of one or more keys of the soft keyboard based on the determined size of the finger of the user comprises:

comparing the determined finger size to a standard finger size;

increasing the size of one or more keys of the soft keyboard in response to the determined size of the finger of the user being larger than a standard finger size; and

decreasing the size of one or more keys of the soft keyboard in response to the determined size of the finger of the user being smaller than a standard finger size.

5. The method of claim 1 , wherein adjusting, by the processor, the size of one or more keys of the soft keyboard based on the determined size of the finger of the user comprises:

generating, by the processor, a display overlay that prompts a user to move the finger of the user in front of the camera such that the image of the finger of the user moves within the display overlay; and

adjusting, by the processor, the size of one or more keys of the soft keyboard based on a movement of the finger of the user within the display overlay.

6. The method of claim 1 , wherein the finger feature comprises one of a distal interphalangeal crease and a proximal interphalangeal crease.

7. A computing device comprising:

a camera;

a display;

a memory; and

a processor coupled to the camera, the display, and the memory, the processor configured with processor-executable instructions to perform operations comprising:

calculating a dimension of a finger feature of a finger of a user of the computing device from an image of the finger captured in an image frame of a camera of the computing device based on parameters of the camera of the computing device comprising:

calculating an object distance of the finger of the user from a lens of the camera based on at least a focal length of the camera and an image distance of the camera comprising:

focusing the camera of the computing device on the finger of the user;

determining the focal length of the camera when focused on the finger; and

calculating the object distance from the camera to the finger based upon the determined focal length; and

calculating, by the processor, the dimension of the finger feature based on at least the object distance of the finger of the user from the lens of the camera, a width of a camera sensor of the camera in pixels, a width of the finger feature in pixels, an angle of a field of view of the camera;

determining a size of the finger of the user based on the calculated dimension of the finger feature; and

adjusting a size of one or more keys of a soft keyboard presented on the display based on the determined size of the finger of the user.

8. The computing device of claim 7 , wherein the processor is configured with processor-executable instructions to perform operations further comprising:

searching the image frame of the camera to find the finger of the user; and

identifying the finger feature in response to finding the finger of the user in the image frame.

9. The computing device of claim 7 , wherein the processor is configured with processor-executable instructions to perform operations such that determining the size of the finger of the user based on the calculated dimension of the finger feature comprises approximating the size of the finger of the user based on an outline of the finger of the user and the calculated dimension of the finger feature.

10. The computing device of claim 7 , wherein the processor is configured with processor-executable instructions to perform operations such that adjusting the size of one or more keys of the soft keyboard based on the determined size of the finger of the user comprises:

comparing the determined finger size to a standard finger size;

increasing the size of one or more keys of the soft keyboard in response to the determined size of the finger of the user being larger than the standard finger size; and

decreasing the size of one or more keys of the soft keyboard in response to the determined size of the finger of the user being smaller than the standard finger size.

11. The computing device of claim 7 , wherein the processor is configured with processor-executable instructions to perform operations such that adjusting the size of one or more keys of the soft keyboard based on the determined size of the finger of the user comprises:

generating a display overlay that prompts the user to move the finger of the user in front of the camera such that the image of the finger of the user moves within the display overlay; and

adjusting the size of one or more keys of the soft keyboard based on a movement of the finger of the user within the display overlay.

12. The computing device of claim 7 , wherein the finger feature comprises one of a distal interphalangeal crease and a proximal interphalangeal crease.

13. A non-transitory processor-readable storage medium having stored thereon processor-executable instructions configured to cause a processor of a computing device to perform operations comprising:

calculating a dimension of a finger feature of a finger of a user of the computing device from an image of the finger captured in an image frame of a camera of the computing device based on parameters of the camera of the computing device comprising:

calculating an object distance of the finger of the user from a lens of the camera based on at least a focal length of the camera and an image distance of the camera comprising:

focusing the camera of the computing device on the finger of the user;

determining the focal length of the camera when focused on the finger; and

calculating the object distance from the camera to the finger based upon the determined focal length; and

calculating, by the processor, the dimension of the finger feature based on at least the object distance of the finger of the user from the lens of the camera, a width of a camera sensor of the camera in pixels, a width of the finger feature in pixels, an angle of a field of view of the camera;

determining a size of the finger of the user based on the calculated dimension of the finger feature; and

adjusting a size of one or more keys of a soft keyboard presented on a display of the computing device based on the determined size of the finger of the user.

14. The non-transitory processor-readable storage medium of claim 13 , wherein the processor-executable instructions are configured to cause the processor of the computing device to perform operations further comprising:

searching the image frame of the camera to find the finger of the user; and

identifying the finger feature in response to finding the finger of the user by searching.

15. The non-transitory processor-readable storage medium of claim 13 , wherein the processor-executable instructions are configured to cause the processor of the computing device to perform operations such that determining the size of the finger of the user based on the calculated dimension of the finger feature comprises approximating the size of the finger of the user based on an outline of the finger of the user and the calculated dimension of the finger feature.

16. The non-transitory processor-readable storage medium of claim 13 , wherein the processor-executable instructions are configured to cause the processor of the computing device to perform operations such that adjusting the size of one or more keys of the soft keyboard based on the determined size of the finger of the user comprises:

comparing the determined finger size to a standard finger size;

increasing the size of one or more keys of the soft keyboard in response to the determined size of the finger of the user being larger than the standard finger size; and

decreasing the size of one or more keys of the soft keyboard in response the determined size of the finger of the user being smaller than the standard finger size.

17. The non-transitory processor-readable storage medium of claim 13 , wherein the processor-executable instructions are configured to cause the processor of the computing device to perform operations such that adjusting the size of one or more keys of the soft keyboard based on the determined size of the finger of the user comprises:

generating a display overlay that prompts the user to move the finger of the user in front of the camera such that the image of the finger of the user moves within the display overlay; and

adjusting the size of one or more keys of the soft keyboard based on a movement of the finger of the user within the display overlay.