A copy control technique using digital watermark information, which makes
it possible to prevent a content from being erroneously subjected to a
copy control process according to wrong copy control information at a
content-to-content transition. Copy control information in the form of
digital watermark information (WM) is embedded in a content to control
copying of the content in accordance with the embedded copy control
information. A content-to-content transition is detected by detecting a
change in a content state, such as a change in image luminance, or a
change in copy control information associated with a content, or is
detected on the basis of a flag, a descriptor, or channel switching. In
response to detection of a content-to-content transition, a reset signal
is output to a WM analyzer to reset current copy control information into
a "undefined" state, so that copy control is performed in a mode such as
a copy-free mode assigned to the "undefined" state.