Multi-channel signal encoding and decoding
AssigneeTelefonaktiebolaget LM Ericsson (publ)
InventorsTor Bjorn Minde, Tomas Lundberg
Life of this patent
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Abstract
A multi-channel linear predictive analysis-by-synthesis signal encoding method determines (S1) a leading channel and encodes the leading channel as an embedded bitstream. Thereafter trailing channels are encoded as a discardable bitstream exploiting cross-correlation to the leading channel.
Claims23
A multi-channel linear predictive analysis-by-synthesis signal encoding method, characterized by
- determining a leading channel and at least one trailing channel lagging behind said leading channel;
- encoding said leading channel as an embedded bitstream;
- encoding trailing channels as a discardable bitstream;
- and
- selecting a trailing channel encoding mode depending on inter-channel correlation to said leading channel.
The method of any of the preceding claims, characterized by
- using channel specific LPC filters for low inter-channel correlation;
- and
- sharing said leading channel LPC filter for high inter-channel correlation.
The method of any of the preceding claims, characterized by
- using channel specific fixed codebooks for low inter-channel correlation;
- and
- sharing said leading channel fixed codebook for high inter-channel correlation.
The method of any of the preceding claims, characterized by adaptively distributing bits between trailing channel fixed codebooks and said leading channel fixed codebook depending on inter-channel correlation.
The method of any of the preceding claims, characterized by
- using channel specific adaptive codebook lags for low inter-channel correlation;
- and
- using a shared adaptive codebook lag for high inter-channel correlation.
A multi-channel linear predictive analysis-by-synthesis signal encoder, characterized by
- means (40) for determining a leading channel and at least one trailing channel lagging behind said leading channel;
- means for encoding said leading channel as an embedded bitstream;
- means for encoding trailing channels as a discardable bitstream;
- and
- means (40) for selecting a trailing channel encoding mode depending on inter-channel correlation to said leading channel.
A terminal including a multi-channel linear predictive analysis-by-synthesis signal encoder, characterized by
- means (40) for determining a leading channel and at least one trailing channel lagging behind said leading channel;
- means for encoding said leading channel as an embedded bitstream;
- means for encoding trailing channels as a discardable bitstream;
- and
- means (40) for selecting a trailing channel encoding mode depending on inter-channel correlation to said leading channel.
Dependencies are inferred from the claim text.