1. An image capture apparatus comprising: an image capture unit configured to capture an image of a subject to obtain image data; an image-capture control unit configured to allow the image capture unit to execute an image capture operation of capturing a plurality of frames of image data having continuity in time so that a frame rate of the image capture unit is changed from a first frame rate to a second frame rate, the second frame rate determined in accordance with a change of a subject brightness level detected during the execution of the image capture operation; and a combination processing unit configured to perform a combination process using, as combination-use image data to be combined, the plurality of frames of image data having continuity in time captured by the image capture unit so as to generate combined-image data representing a still image, wherein the image-capture control unit performs an exposure adjustment control operation, comprising extracting at least one non-flash image from the plurality of frames, calculating an average brightness value for each of the extracted non-flash images, classifying the extracted non-flash images into a plurality of groups based on the average brightness values, designating one of the groups as a representative group, calculating an average value of average brightness values for the representative group, calculating a correction coefficient for each of the extracted non-flash images by comparing the average brightness value of the extracted non-flash image to the average value, and for each of the extracted non-flash images, multiplying all of the pixels of the extracted non-flash image by the correction coefficient.