1. A portable terminal for generating three-dimensional (3D) image files based on two-dimensional (2D) image media standards, the portable terminal comprising: one or more cameras configured to photograph first image data and second image data; an image signal processing unit configured to pre-process the first image data and the second image data; a storing unit configured to store the first image data and the second image data; an encoding unit configured to encode the first image data and the second image data; and a file generating unit configured to generate a 3D image file, wherein the 3D image file comprises a first area having the first image data and the second image data synchronized with the first image data so as to be used for generating a 3D image, a second area comprising at least information on a number of frames and a size of each frame for the first image data, and a third area, separate from the second area, comprising information on a number of frames and a size of each frame for the second image data, wherein information stored in third area is for regenerating the 3D image and not for regenerating a 2D image.