Image capturing apparatus comprising focus detection, and method for controlling the same

Patent metadata

Field	Value
Publication number	US-9451150-B2
Application number	US-201314103331-A
Country	US
Kind code	B2
Filing date	Dec 11, 2013
Priority date	Dec 21, 2012
Publication date	Sep 20, 2016
Grant date	Sep 20, 2016

Abstract

An image capturing apparatus comprises: a focus detection unit to obtain an in-focus position for each preset focus detection area; a setting unit to set an object area for a captured image; an acquisition unit to acquire a representative in-focus position of the object area based on in-focus positions contained within a given range where in-focus positions of focus detection areas corresponding to the object area are most concentrated; a determination unit to determine, if a plurality of object areas are set by the setting unit, a priority order of the object areas based on representative in-focus positions of the object areas; and a control unit configured to perform control so as to sequentially drive the focus lens to the representative in-focus positions of the object areas in decreasing order of the priority order and perform shooting.

First claim

What is claimed is:

1. An image capturing apparatus comprising:
a focus detection unit configured to obtain an in-focus position for each of a plurality of preset focus detection areas, the in-focus position indicating a position to which a focus lens is to be driven in order to achieve focus;
a setting unit configured to set an object area with respect to a captured image;
an acquisition unit configured to acquire, for each object area set by the setting unit, a representative in-focus position, wherein the acquisition unit classifies the focus detection areas included in each object area into a plurality of groups in such a manner that differences between the in-focus positions of the focus detection areas that belong to each group fall within a first predetermined range, and obtains the representative in-focus position for each object area based on the in-focus positions of the focus detection areas included in a group to which a largest number of the focus detection areas belong;
a determination unit configured to determine, if a plurality of object areas are set by the setting unit, a priority order of the object areas based on representative in-focus positions respectively acquired for the object areas; and
a control unit configured to perform control so as to sequentially drive the focus lens to the representative in-focus positions of the object areas in decreasing order of the priority order determined by the determination unit and perform shooting with a plurality of different focus lens positions.

2. The image capturing apparatus according to claim 1 , further comprising:
an object detection unit configured to detect a predetermined object from the captured image,
wherein if the predetermined object is detected by the object detection unit, the focus detection unit resets an area of the detected object as a focus detection area and obtains an in-focus position of the reset focus detection area.

3. The image capturing apparatus according to claim 2 , wherein if the focus detection area is reset, the acquisition unit acquires the in-focus position of the reset focus detection area as the representative in-focus position of an object area corresponding to the detected object.

4. The image capturing apparatus according to claim 1 , wherein if a plurality of object areas are set by the setting unit, the acquisition unit integrates a plurality of object areas so that the in-focus positions of focus detection areas included in each integrated object area are situated within a second predetermined range that is wider than the first predetermined range, and acquires the representative in-focus position for each integrated object area.

5. The image capturing apparatus according to claim 1 , wherein the acquisition unit acquires an in-focus position on a closest distance side, of the in-focus positions of the focus detection areas included in the group to which the largest number of the focus detection areas belong, as the representative in-focus position.

6. The image capturing apparatus according to claim 1 , wherein the acquisition unit acquires the representative in-focus position based on a statistical value of the in-focus positions of the focus detection areas included in the group to which the largest number of the focus detection areas belong.

7. The image capturing apparatus according to claim 1 , wherein if no group that includes more than a predetermined number of focus detection areas exists, the acquisition unit acquires an in-focus position on a closest distance side, of the in-focus positions of the focus detection areas included in the object area, as the representative in-focus position.

8. The image capturing apparatus according to claim 1 , wherein the determination unit determines the priority order based further on at least either of positions of the object areas in the image and sizes of the object areas.

9. A method for controlling an image capturing apparatus, the method comprising:
obtaining an in-focus position for each of a plurality of preset focus detection areas, the in-focus position indicating a position to which a focus lens is to be driven in order to achieve focus;
setting an object area with respect to a captured image;
classifying the focus detection areas included in each object area into a plurality of groups in such a manner that differences between the in-focus positions of the focus detection areas that belong to each group fall within a first predetermined range;
acquiring, for each object area representative in-focus position based on the in-focus positions of the focus detection areas included in a group to which a largest number of the focus detection areas belong;
determining, if a plurality of object areas are set, a priority order of the object areas based on representative in-focus positions respectively acquired for the object areas; and
performing control so as to sequentially drive the focus lens to the representative in-focus positions of the object areas in decreasing order of the priority order and perform shooting with a plurality of different focus lens positions.

10. A non-transitory readable storage medium having stored thereon a program which is executable by an image processing apparatus, the program having a program code for realizing the control method comprising:
obtaining an in-focus position for each of a plurality of preset focus detection areas, the in-focus position indicating a position to which a focus lens is to be driven in order to achieve focus;
setting an object area with respect to a captured image;
classifying the focus detection areas included in each object area into a plurality of groups in such a manner that differences between the in-focus positions of the focus detection areas that belong to each group fall within a first predetermined range;
acquiring, for each object area, a representative in-focus position based on the in-focus positions of the focus detection areas included in a group to which a largest number of the focus detection areas belong;
determining, if a plurality of object areas are set, a priority order of the object areas based on representative in-focus positions respectively acquired for the object areas; and
performing control so as to sequentially drive the focus lens to the representative in-focus positions of the object areas in decreasing order of the priority order and perform shooting with a plurality of different focus lens positions.

11. An image capturing apparatus comprising:
a focus detection unit configured to obtain an in-focus position for each of a plurality of preset focus detection areas, the in-focus position indicating a position to which a focus lens is to be driven in order to achieve focus;
a setting unit configured to set object areas with respect to a captured image;
an acquisition unit configured to acquire, for each object area set by the setting unit, a representative in-focus position, wherein the acquisition unit classifies the focus detection areas included in each object area into a plurality of groups in such a manner that differences between the in-focus positions of the focus detection areas that belong to each group fall within a first predetermined range, and obtains the representative in-focus position for each object area based on the in-focus positions of the focus detection areas included in a group to which a largest number of the focus detection areas belong; and
a control unit configured to perform control so as to sequentially drive the focus lens to the representative in-focus positions of the object areas and perform shooting with a plurality of different focus lens positions.

12. A method for controlling an imag

Assignees

• Canon Kk

Inventors

• Shibagami Genjiro

Classifications

• H04N23/743

  Bracketing, i.e. taking a series of images with varying exposure conditions · CPC title

• H04N23/635

  Region indicators; Field of view indicators · CPC title

• H04N23/676 Primary

  Bracketing for image capture at varying focusing conditions · CPC title

• H04N23/673 Primary

  based on contrast or high frequency components of image signals, e.g. hill climbing method · CPC title

• H04N5/23212 Primary

  Electricity · mapped topic