Image processing device, control method thereof, imaging device, and recording medium

An imaging device comprising:

• an imaging optical system;
• an imaging element;
• at least one processor and a memory holding a program which makes the processor function as
• an acquisition unit configured to acquire a plurality of image signals having different viewpoints,
• a division unit configured to divide a region within an image into a plurality of regions,
• a parallax amount calculation unit configured to calculate an amount of parallax by performing a correlation operation of the plurality of image signals with respect to a plurality of divided regions divided by the division unit,
• a distance calculation unit configured to calculate distance information of a subject based on the amount of parallax,
• a reliability calculation unit configured to calculate a reliability which is an index for the distance information in the correlation operation,
• a generation unit configured to generate a histogram representing a frequency distribution of the distance information, and
• a control unit configured to perform focus adjustment control on the imaging optical system using focus detection information acquired by the parallax amount calculation unit,
• wherein, if a plurality of pieces of the distance information are present in the divided regions, the generation unit generates the histogram using the plurality of pieces of distance information and the reliability.

A control method which is executed in an image processing device that acquires and processes a plurality of image signals having different viewpoints, the method comprising:

• dividing a region within an image into a plurality of regions;
• calculating an amount of parallax by performing a correlation operation of the plurality of image signals with respect to a plurality of divided regions divided in the dividing;
• calculating distance information of a subject based on the amount of parallax;
• calculating a reliability which is an index for the distance information in the correlation operation;
• and
• generating a histogram representing a frequency distribution of the distance information,
• wherein the generating includes, if a plurality of pieces of the distance information are present in the divided region, generating the histogram using the plurality of pieces of distance information and the reliability.

A non-transitory recording medium storing a control program of an image processing device that acquires and processes a plurality of image signals having different viewpoints causing a computer to perform each step of a control method of the image processing device, the method comprising:

• dividing a region within an image into a plurality of regions;
• calculating an amount of parallax by performing a correlation operation of the plurality of image signals with respect to a plurality of divided regions divided in the dividing;
• calculating distance information of a subject based on the amount of parallax;
• calculating a reliability which is an index for the distance information in the correlation operation;
• and
• generating a histogram representing a frequency distribution of the distance information,
• wherein the generating includes, if a plurality of pieces of the distance information are present in the divided region, generating the histogram using the plurality of pieces of distance information and the reliability.