摘要 |
<p>The invention relates to methods and corresponding systems for embedding a host signal (1) with auxiliary information (6) comprising the steps of filtering the host signal using appropriate filter(s) (2,10) to produce a modified signal and encoding the auxiliary information within the modified signal in an encoder (5) using a cross-correlation technique. In order to improve the performance of the encoding process with respect to the correlation delay, the present invention uses the appropriate filters to remove dominant tonal components by flattening the power spectrum of a host signal and/or also to remove low frequency components. The removal of dominant tonal components and/or to low frequency components prior to the encoding or decoding process improves the performance of the encoding/decoding process. The removed components are subsequently re-introduced by filtering (21) and/or summing (8) to ensure the encoded signal (9) is not perceptibly different to the unencoded signal (1).</p> |