A picture signal processing system includes a playback apparatus and a display apparatus connected via first and second communication units. The playback apparatus receives a video signal made up of source data generated by moving giant image data in a constant direction at a constant speed, wherein the giant image data has a number of pixels far greater than the number of pixels in a display region. The playback apparatus reads source data speed information stored in the video signal header, and transmits the video signal and the speed information to the display apparatus. The display apparatus references a table to determine how to process the video signal on the basis of the speed information, processes the video signal, and then displays the processed video signal.