A method includes recognizing a face in a plurality of preview images. The method also includes setting a first exposure value of a first image such that a first brightness falls within a specified brightness range and the first brightness is of a first area including the face. The method further includes extracting a second brightness of an area excluding the first area. When the difference between the first brightness and the second brightness is greater than or equal to a specified value, the method includes adjusting exposure values of second and third images, which are a plurality of bracketing images having different exposures, as second and third exposure values, respectively. Additionally, the method includes synthesizing at least one of a bracketing image having a first exposure value, a second image, or a third image to generate a high dynamic range (HDR) image. The method includes displaying the HDR image.