1. A method of determining an image compression format, the method comprising: encoding a high-quality image comprised in a 3-dimensional (3D) stereo image, wherein the 3D stereo image comprises the high-quality image and a low-quality image; determining an image compression format in which a resolution of an encoded low-quality image is higher than or equal to a reference value based upon a resolution of the encoded high-quality image; encoding the low-quality image according to the determined image compression format; transmitting the encoded high-quality image through a first channel; and transmitting the encoded low-quality image through a second channel.