Patent ID: 8428941
Filing Date: 2013-04-23
Classification: G10L

Abstract:
1. A method for lossless encoding of a source signal, using a lossy encoded data stream and a lossless extension data stream which together form a lossless encoded data stream for said source signal, said method comprising the steps: lossy encoding said source signal, wherein said lossy encoding provides said lossy encoded data stream as well as spectral whitening data; correspondingly lossy decoding said lossy encoded data, thereby reconstructing a standard decoded signal and, using said spectral whitening data, constructing from said standard decoded signal a superior quality decoded signal; forming a difference signal between said source signal and said superior quality decoded signal and lossless encoding said difference signal; packing said encoded difference signal together with said spectral whitening data to form said lossless extension data stream, wherein said spectral whitening data are generated by: and wherein said lossless encoding of said difference signal uses an entropy encoder, the input signal of which passes through an LPC de-correlator only if said escape signal is set.