Parallax detecting apparatus, image capturing apparatus, parallax detecting method, and storage medium

A parallax detecting method executed by a parallax detecting apparatus, the method comprising:

• obtaining a first viewpoint image and a second viewpoint image that have different viewpoints from each other in a first direction;
• obtaining displacement information that specifies a displacement amount in a second direction between positions in the first viewpoint image and the second viewpoint image corresponding to a same position in a shooting range, wherein the displacement amount varies in conformity with a parallax amount in the first direction between the positions, the parallax amount being in conformity with a defocus amount, and wherein the second direction is perpendicular to the first direction;
• selecting, in the first viewpoint image, a base region corresponding to a base position of parallax amount detection;
• performing correlation calculation processing with respect to each of a plurality of reference regions corresponding to a plurality of reference positions in the second viewpoint image, wherein the correlation calculation processing includes first correction processing and calculation processing, wherein the first correction processing corrects at least one of a position of the base region in the second direction and a position of the reference region in the second direction based on the displacement information so as to reduce a displacement that occurs between the base position and the reference position in the second direction and that is in conformity with a parallax amount in the first direction between the base position and the reference position, and wherein the calculation processing calculates a correlation between the base region and the reference region that reflect the first correction processing;
• and
• detecting a parallax amount in the first direction at the base position based on each correlation between the base region and each of the plurality of reference regions.

A non-transitory computer-readable storage medium which stores a program for causing a computer to execute a parallax detecting method, the method comprising:

• obtaining a first viewpoint image and a second viewpoint image that have different viewpoints from each other in a first direction;
• obtaining displacement information that specifies a displacement amount in a second direction between positions in the first viewpoint image and the second viewpoint image corresponding to a same position in a shooting range, wherein the displacement amount varies in conformity with a parallax amount in the first direction between the positions, the parallax amount being in conformity with a defocus amount, and wherein the second direction is perpendicular to the first direction;
• selecting, in the first viewpoint image, a base region corresponding to a base position of parallax amount detection;
• performing correlation calculation processing with respect to each of a plurality of reference regions corresponding to a plurality of reference positions in the second viewpoint image, wherein the correlation calculation processing includes first correction processing and calculation processing, wherein the first correction processing corrects at least one of a position of the base region in the second direction and a position of the reference region in the second direction based on the displacement information so as to reduce a displacement that occurs between the base position and the reference position in the second direction and that is in conformity with a parallax amount in the first direction between the base position and the reference position, and wherein the calculation processing calculates a correlation between the base region and the reference region that reflect the first correction processing;
• and
• detecting a parallax amount in the first direction at the base position based on each correlation between the base region and each of the plurality of reference regions.