The invention provides a method for obtaining related information about a media program containing an
audio signal, comprising: an embedding step of embedding an
audio watermark containing identification information of the media program into the
audio signal of the media program; a transmitting step of transmitting the media program; a recording step of recording by a user a portion of the
audio signal of the media program embedded with the
audio watermark; an extracting step of extracting the
audio watermark from the recorded portion of the audio
signal to obtain the identification information and providing the identification information to a
server storing the related information; and a related information providing step of providing the user with the related information about the media program according to the identification information from the
server, wherein the embedding step comprises: identification information pre-
processing step of performing a pre-
processing on the identification information of the media program to obtain pre-processed identification information of the media program; echo
delay array determining step of determining an echo
delay array used in embedding a plurality of pairs of antipodal echoes into the audio
signal; amplitude modulating step of modulating amplitudes of the plurality of pairs of antipodal echoes with the pre-processed identification information; echo repeating step of repeating the amplitude-modulated plurality of pairs of antipodal echoes; and echo embedding step of embedding the repeated and amplitude-modulated plurality of pairs of antipodal echoes into the audio
signal along the echo
delay array.