Determining camera auto-focus settings

Patent metadata

Field	Value
Publication number	US-9826156-B1
Application number	US-201514741248-A
Country	US
Kind code	B1
Filing date	Jun 16, 2015
Priority date	Jun 16, 2015
Publication date	Nov 21, 2017
Grant date	Nov 21, 2017

Abstract

A system and method of determining a tilt angle of a portable computing device using sensor data; identifying a tilt angle from a plurality of predetermined tilt angle ranges; determining focal length settings for image capture devices of the portable computing device using the tilt angle, adjustment increments, and autofocus scan range algorithms. A portable computing device including a processor; a first image capture device on a first side of the portable computing device, and a second image capture device on the second side of the portable computing device, the second side located opposite of the first side; and a memory device including instructions operable to be executed by the processor to perform a set of actions, enabling the portable computing device to perform the method.

First claim

What is claimed is:

1. A system, comprising:
a processor;
a first image capture device on a first side of the system;
a second image capture device on a second side of the system, wherein the second side opposes the first side;
a memory device including instructions operable to be executed by the processor to perform a set of actions, enabling the system to:
determine a tilt angle of the system using sensor data;
identify a tilt angle range from a plurality of predetermined tilt angle ranges, wherein the tilt angle range overlaps with the tilt angle of the system;
determine a first focal length setting for the first image capture device using a first associative array that associates the tilt angle range with the first focal length setting;
determine a first adjustment increment for the first image capture device using a second associative array that associates the tilt angle range with the first adjustment increment;
determine a second focal length setting for the first image capture device using the first adjustment increment according to a first autofocus scan range algorithm;
determine a third focal length setting for the second image capture device using a third associative array that associates the tilt angle range with the third focal length setting;
determine a second adjustment increment for the second image capture device using a fourth associative array that associates the tilt angle range with the second adjustment increment; and
determine a fourth focal length setting for the second image capture device using the second adjustment increment according to a second autofocus scan range algorithm.

2. The system of claim 1 , further comprising a sensor that generates the sensor data, and wherein the sensor data indicates a gravitational pull on the system.

3. The system of claim 1 , the set of actions further comprising enabling the system to:
capture first image data including a representation of an object within a field of view of the first image capture device;
determine an identity of the object by comparing the first image data with second image data of known objects;
determine a dimension of the object by comparing the identity of the object with dimensional data of known objects;
determine a distance from the first image capture device to the object by comparing the dimension of the object with a scale of the object represented in the first image data relative to known dimensions of the field of view of the first image capture device;
determine the first focal length setting to focus the first image capture device at the distance; and
determine the first adjustment increment using a fifth associative array that associates the distance with the first adjustment increment.

4. A method comprising:
obtaining tilt angle data representing a tilt angle of a portable computing device relative to an axis, the portable computing device comprising a first image capture device and a second image capture device;
determining a first focal length setting for the first image capture device based at least in part on the tilt angle data;
determining a first adjustment increment for the first image capture device based at least in part on the tilt angle data;
determining a second focal length setting for the first image capture device by using the first adjustment increment according to a first autofocus scan range algorithm;
determining a third focal length setting for the second image capture device based at least in part on the tilt angle data;
determining a second adjustment increment for the second image capture device based at least in part on the tilt angle data; and
determining a fourth focal length setting for the second image capture device by using the second adjustment increment according a second autofocus scan range algorithm.

5. The method according to claim 4 , further comprising:
determining the tilt angle data using at least one of a gyroscope and an accelerometer to determine the tilt angle of the portable computing device relative to a direction of gravity.

6. The method of claim 4 , wherein determining the first focal length setting is further based at least in part on altitude data representing an altitude of the portable computing device.

7. The method of claim 6 , further comprising:
assigning a first weight factor to the tilt angle data; and
assigning a second weight factor to the altitude data; and
determining the first autofocus scan range algorithm based at least in part on the first weight factor and the second weight factor.

8. The method of claim 7 , further comprising:
determining that the altitude of the portable computing device exceeds a predetermined altitude; and
assigning the second weight factor to be greater than the first weight factor.

9. The method of claim 4 , further comprising identifying a touch gesture on a touch screen of the portable computing device, wherein determining the first focal length setting is further based at least in part on the touch gesture.

10. A portable computing device, comprising:
a processor;
a first image capture device;
a second image capture device;
a memory device including instructions operable to be executed by the processor to perform a set of actions, enabling the portable computing device to:
obtain tilt angle data representing a tilt angle of the portable computing device relative to an axis;
determine a first focal length setting for the first image capture device based at least in part on the tilt angle data;
determine a first adjustment increment for the first image capture device based at least in part on the tilt angle data;
determine a second focal length setting for the first image capture device by using the first adjustment increment according to a first autofocus scan range algorithm;
determine a third focal length setting for the second image capture device based at least in part on the tilt angle data;
determine a second adjustment increment for the second image capture device based at least in part on the tilt angle data; and
determine a fourth focal length setting for the second image capture device by using the second adjustment increment according a second autofocus scan range algorithm.

11. The portable computing device according to claim 10 , further comprising at least one of a gyroscope and an accelerometer, and wherein the set of actions further enable the portable computing device to: determine the tilt angle data using at least one of the gyroscope and the accelerometer to determine the tilt angle of the portable computing device relative to a direction of gravity.

12. The portable computing device according to claim 10 , further comprising a touch screen, and wherein the set of actions further enable the portable computing device to:
identify a touch gesture on the touch screen; and
determine at least one of the first focal length setting for the first image capture device or the second focal length setting for the second image capture device based at least in part on the touch gesture.

13. The portable computing device according to claim 10 wherein the set of actions further enable the portable computing device to:
identify a first object within a field of view of the first image capture device;
determine a distance from the portable computing device to the first object based at least in part on a known characteristic of the first object; and
analyze the distance to determine the first focal length setting, wherein the first focal length setting focuses the first image capture device at the distance.

14. The portable computing device according to claim 10 wherein

Assignees

• Amazon Tech Inc

Inventors

• Liu Yue
• Sikka Avnish

Classifications

• H04N23/45

  for generating image signals from two or more image sensors being of different type or operating in different modes, e.g. with a CMOS sensor for moving images in combination with a charge-coupled device [CCD] for still images · CPC title

• H04N23/698

  for achieving an enlarged field of view, e.g. panoramic image capture · CPC title

• G03B13/36 Primary

  Autofocus systems · CPC title

• H04N23/681 Primary

  Motion detection · CPC title

• H04N23/67

  Focus control based on electronic image sensor signals · CPC title