Abstract: An encoding and decoding method for digital audio watermarking and data hiding in transient acoustic content is disclosed. The audio signal is segmented into overlapping frames and each frame is decomposed into frequency bands. A special transient detector is used to detect frames characterized by transient audio signals (rapidly rising signal amplitude envelope and a relatively broadband spectrum with rapidly evolving spectral content, such as speech fricatives, drum beats, etc.). Frames falling on or containing transients are detected and encoded with binary watermark data by unconditionally hard-modulating the signal frequency band signals according to rules determined by the value of the respective associated binary data bits of the watermark data and without reference to the characteristics of the watermarked band signals. The method is undetectable by human listeners and unusually resistant to the degrading effects of acoustic reverberation.

Abstract: The invention relates to a method of suppressing undesired noise in a hearing aid, the hearing aid comprising a handheld unit, in which a microphone is integrated, and another microphone located externally of the handheld unit and connected thereto.

Abstract: A method of acoustic matching of audio recordings by means of acoustic fingerprinting is disclosed. An acoustic fingerprint is extracted from a fragment of an audio recording. The fingerprint represents a highly discriminative compact digital digest (acoustic hash) of the acoustic recording and consists of smaller digital entities called acoustic sub-fingerprints (acoustic hash-words), computed from perceptually essential properties of the acoustic recording. Two acoustic fingerprints corresponding to two audio fragments are matched to determine degree of acoustic similarity of the two audio fragments.

Abstract: A watermarking key consisting of a sequence of elements is embedded into a data sequence. Each element may take on two or more values. In order to embed a watermarking key, first a reference sequence is divided into blocks. Each element of the watermarking key is associated with a respective block of the reference sequence. A watermarked sequence is then generated by shifting the associated blocks by a degree determined by the value of the respective associated element of the watermarking key.

Abstract: A watermarking key consisting of a sequence of elements is embedded into a data sequence. Each element may take on two or more values. In order to embed a watermarking key, first a reference sequence is divided into blocks. Each element of the watermarking key is associated with a respective block of the reference sequence. A watermarked sequence is then generated by shifting the associated blocks by a degree determined by the value of the respective associated element of the watermarking key.