Forensic watermarking during AAC playback

Kirbiz S., Celik M., Lemma A., Katzenbeisser S.

IEEE International Conference on Multimedia and Expo (ICME 2007), Beijing, China, 2 - 05 July 2007, pp.1111-1112 identifier

  • Publication Type: Conference Paper / Full Text
  • City: Beijing
  • Country: China
  • Page Numbers: pp.1111-1112


We propose a method for embedding a robust forensic tracking watermark within the AAC decoder during audio playback. For predefined frequency bands, the method intercepts and modifies the scale-factors, which are present in the AAC bit-stream. It thereby modulates the short-time envelope of the band-limited audio and embeds a watermark which is robust to various attacks such as recompression and acoustic transmission. Due to its low complexity-a few additions per AAC frame-the method is suitable for implementation even in resource constrained devices such as portable players. Furthermore, decode-time embedding enables dynamic payload assignments which may be used to signal playback time and location.