1. A method for providing a stereoscopic image, comprising: storing a first image; receiving a second image that forms a stereoscopic image with the first image; synchronizing the stored first image and the received second image; and outputting the stereoscopic image generated by the synchronized images, wherein at least one of the first image and the second image is a digital broadcasting program, wherein the first image is stored before a time of broadcasting the digital broadcasting program, and wherein the second image is received at the time of broadcasting the digital broadcasting program according to a broadcasting schedule, wherein said synchronizing the stored first image and the receiving second image includes: extracting time reference values of the first image and the second image, and synchronizing the first image and the second image using the extracted time reference values, wherein in said synchronizing the first image and the second image using the extracted time reference values, at least one of time stamps of the first image and the second image is corrected according to the extracted time reference values.