Patent ID: 9548055
Date: 2017-01-17
CPC Classifications: G10L

Claim:
1. A lossless audio encoder adapted to receive an input digital audio signal at a first sampling rate and to generate therefrom a PCM digital audio output comprising a plurality of samples and having a second sampling rate lower than the first sampling rate, wherein: each of the plurality of samples has a more significant portion and a less significant portion; the more significant portions and the less significant portions together contain information that allows a first decoder to recover losslessly the input digital audio signal; the more significant portions, when interpreted as a standard PCM stream, provide a first lossy representation of a version of the input digital audio signal having a reduced bandwidth; the more significant portions contain information that allows a second decoder to recover a second lossy representation of the input digital audio signal having a bandwidth greater than that of the first lossy representation, said input digital audio signal is coupled to a lossless bandsplitter having a high frequency output and a low frequency output, the high frequency output being coupled to a compression unit having a lossy compressed output and a restitution output, the more significant portions are derived in dependence on the low frequency output and the lossy compressed output, and the less significant portions are derived in dependence on the restitution output, and the lossless audio encoder is implemented by at least one of hardware or a combination of hardware and software.