1. An image processing apparatus comprising: a first optical image generation unit configured to generate optical low frequency image data from input optical image data; a first digital imaging unit configured to obtain digital low frequency image data from the optical low frequency image data generated by the first optical image generation unit; a second digital imaging unit configured to obtain digital image data from the input optical image data; a memory configured to store instructions; and one or more processors configured to execute the instructions stored in the memory to provide: a second generation unit configured to generate digital high frequency image data from the digital image data that is obtained by the second digital imaging unit; and a third generation unit configured to generate output image data based on both of the digital low frequency image data that is obtained by the first digital imaging unit and the digital high frequency image data that is generated by the second generation unit.