Back to results
US 2026/0038523 A1Published application
Truncateable predictive coding
AssigneeTelefonaktiebolaget LM Ericsson (publ)
InventorsErik NORVELL, Fredrik JANSSON
Life of this patent
Estimating the term…
Abstract
A method, system, and computer program to encode and decode a channel coherence parameter applied on a frequency band basis, where the coherence parameters of each frequency band form a coherence vector. The coherence vector is encoded and decoded using a predictive scheme followed by a variable bit rate entropy coding.
Claims23
An encoder comprising:
- memory;
- and
- processing circuitry, wherein the encoder is configured to perform a method comprising:
- I) producing prediction residuals, wherein producing the prediction residuals comprises:
- a) obtaining a coherence vector associated with an audio frame of an audio signal, wherein, the coherence vector comprises a coherence value for each frequency band included in a set of two or more frequency bands;
- and
- b) for each frequency band in the set of frequency bands:
- i) obtaining an intra-frame prediction of the coherence value for the frequency band;
- ii) obtaining an inter-frame prediction of the coherence value for the frequency band;
- iii) calculating a weighted prediction of the coherence value for the frequency band using:
- i) the intra-frame prediction of the coherence value for the frequency band, ii) the inter-frame prediction of the coherence value for the frequency band, and iii) a weighting factor;
- and
- iv) producing a prediction residual for the frequency band using the coherence value for the frequency band and the weighted prediction of the coherence value for the frequency band;
- II) encoding the prediction residuals using a variable bit rate scheme, thereby producing encoded prediction residuals;
- and
- III) including the encoded prediction residuals in a bitstream.
13 more elements
A decoder comprising:
- memory;
- and
- processing circuitry, wherein the decoder is configured to perform a method for obtaining reconstructed coherency values associated with an audio signal, the method comprising:
- obtaining an intra-frame prediction value for a first frequency band;
- obtaining an inter-frame prediction value for the first frequency band;
- calculating a weighted prediction of a coherence value for the first frequency band using:
- i) the intra-frame prediction value, ii) the inter-frame prediction value, and iii) a weighting factor;
- obtaining from a bitstream an encoded prediction residual associated with the first frequency band;
- decoding the encoded prediction residual, thereby producing a decoded prediction residual associated with the first frequency band;
- and
- obtaining a first reconstructed coherency value associated with the first frequency band using the weighted prediction of the coherence value for the first frequency band and the decoded prediction residual associated with the first frequency band.
8 more elements
An audio encoding method comprising:
- producing prediction residuals, wherein producing the prediction residuals comprises:
- obtaining a coherence vector associated with an audio frame of an audio signal, wherein, the coherence vector comprises a coherence value for each frequency band included in a set of two or more frequency bands;
- and
- for each frequency band in the set of frequency bands:
- obtaining an intra-frame prediction of the coherence value for the frequency band;
- obtaining an inter-frame prediction of the coherence value for the frequency band;
- calculating a weighted prediction of the coherence value for the frequency band using:
- i) the intra-frame prediction of the coherence value for the frequency band, ii) the inter-frame prediction of the coherence value for the frequency band, and iii) a weighting factor;
- and
- producing a prediction residual for the frequency band using the coherence value for the frequency band and the weighted prediction of the coherence value for the frequency band;
- encoding the prediction residuals using a variable bit rate scheme, thereby producing encoded prediction residuals;
- and
- including the encoded prediction residuals in a bitstream.
10 more elements
A method for obtaining reconstructed coherency values associated with an audio signal, the method comprising:
- obtaining an intra-frame prediction value for a first frequency band;
- obtaining an inter-frame prediction value for the first frequency band;
- calculating a weighted prediction of a coherence value for the first frequency band using:
- i) the intra-frame prediction value, ii) the inter-frame prediction value, and iii) a weighting factor;
- obtaining from a bitstream an encoded prediction residual associated with the first frequency band;
- decoding the encoded prediction residual, thereby producing a decoded prediction residual associated with the first frequency band;
- and
- obtaining a first reconstructed coherency value associated with the first frequency band using the weighted prediction of the coherence value for the first frequency band and the decoded prediction residual associated with the first frequency band.
5 more elements
Dependencies are inferred from the claim text.