Information signal copvright protection method, information signal recording method and device, and information signal output method and device

摘要

A copyright protection method and apparatus, an output method and device, and a recording method and device for protecting information signals that are transmitted and stored in both a baseband signal status and a compressed encoded data status are provided. The method includes the steps of superimposing a first copyright protection information as a digital watermark on a signal in a baseband state, and compression encoding the signal in the baseband state to form an information signal in a compressed encoded data state. The signal in the baseband state and the signal in the compressed encoded data state are then transmitted from a first apparatus to a second apparatus. The second apparatus determines whether rewriting of the first copyright protection information superimposed on the signal in the baseband state and the signal in the compressed encoded data state is necessary, and if it is determined that rewriting of the first copyright protection information is necessary, rewrites the first copyright protection information as a digital watermark on the signal in said baseband state only. <IMAGE>