1. A method for controlling an operation of a mobile terminal, the method comprising: displaying a two-dimensional (2D) preview image of an object being captured by a camera on a screen of a display module in response to selection of a three-dimensional (3D) capture mode; establishing a predictive image window in a region of the screen; concurrently displaying a predictive image on the predictive image window while the preview image is displayed on the remaining portion of the screen to allow the predictive image to be viewed separately from the preview image, the predictive image comprising a predicted result of a three-dimensional (3D) stereoscopic image that can be generated using a plurality of combined images comprising the preview image and at least one previously captured 2D image of the object; and displaying a plurality of identification (ID) numbers on the predictive image window, each of the plurality of ID numbers indicating an ordinal number of each of the plurality of combined images.