Imaging device and method for its image processing

an imaging device comprising:

• a first operation input unit configured to receive a photographing instruction from a user;
• a photographing optical system including a focus-shift structure configured to shift a focal position;
• an image sensing element configured to convert an optical image of a photographing subject received from the photographing optical system to image data;
• an image processing unit including a face region detecting unit and a photographing subject frequency information capturing unit, wherein the face region detecting unit is configured to detect a face region from the image data and obtain face region information indicating the detected face region, and wherein the photographing subject frequency information capturing unit is configured to capture focus degree information indicating a degree of focus for each detected face region.
• a recording unit configured to record a file;
• and
• a control unit configured to control the first operation input unit, the photographing optical system, the image processing unit and the recording unit;
• and
• wherein the control unit obtains plural image data with different focal positions by controlling the focal position of the photographing optical system in response to the photographing instruction, obtains the face region information and the focus degree information for each image data, and stores the plural image data, the face region information and the focus degree information in the recording unit as a single file.