A method and arrangement are disclosed for distributing multimedia content
such that that the actual distribution of said content can be monitored
in an efficient and reliable manner. The invention combines the
extensiveness of feature extraction and the robustness of watermarking.
Characteristic features of the content, e.g. luminance distribution, are
extracted (11) to constitute a signature (SIG) of the content. In
addition, a watermark is embedded (12) having a payload representing an
index (ID) in a database (10) in which the content to be monitored is
stored. The watermark serves as an index for limiting the database search
needed for monitoring the signatures.