Patent ID: 7260225

Claim:
Device for processing a stereo audio signal having a first channel and a second channel to obtain a modified stereo signal having a modified first channel and a modified second channel to be inpute into an encoder using an encoding algorithm comprising: an analyzer for analyzing said stereo audio signal or a signal derived from said stereo audio signal to obtain a measure for the quantity of bits required by a coder to code said stereo audio signal using a coding algorithm; and a modifier for modifying said first and said second channel to obtain a modified first and a modified second channel, said modifier responding to said analyzer to become effective when said measure for the quantity of bits exceeds a predetermined measure, and said modifier being designed in such a way that a characteristic of a sum signal of said first and said second modified channel, the characteristic having a similar course as the energy of the sum signal, is in a predetermined relation to the characteristic of a sum signal of said first and said second channel and that a difference signal of said first and said second modified channel is attenuated in contrast to a difference signal of said first and said second channel.