An electronic device includes a first image sensor, a second image sensor, one or more image processing modules, and a display. The first image sensor generates first image data. The second image sensor generates second image data. The one or more image processing modules process one or more image data among the first image and the second image data. The display displays the one or more image data among the first image data or second image data processed by the one or more image processing modules. The thumbnail generation module generates thumbnail data using the one or more image data among the first image data and second image data processed by the one or more image processing modules. A method includes converting the plurality of image data into a format displayable on a display, and generating thumbnail data using the image data of the displayable format.