摘要:
A method and a device for processing a stereo signal obtained from an encoder, which codes an N-channel audio signal into spatial parameters (P) and a stereo down-mix comprising first and second stereo signals (L 0 , R 0 ). A first signal and a third signal are added in order to obtain a first output signal (L 0w ), wherein the first signal QL 0wL ) comprises the first stereo signal (L 0 ) modified by a first complex function (g 1 ), and the third signal (L 0wR ) comprises the second stereo signal (R 0 ) modified by a third complex function (g 3 ). A second signal and a fourth signal are added to obtain a second output signal (R 0w ). The fourth signal (R 0wR ) comprises the second stereo signal (R 0 ) modified by a fourth complex function (g 4 ), and the second signal (R 0wL ) comprises the first stereo signal (L 0 ) modified by a second complex function (g 2 ). The complex functions (g 1 ,g 2 ,g 3 ,g 4 ) are functions of the spatial parameters (P) and are chosen such that an energy value of the difference (L 0wL -P 0wL ) between the first signal and the second signal is larger than or equal to the energy value of the sum (L 0wL +R 0wL ) of the first and the second signal and the energy value of the difference (R 0wR -L 0wR ) between the fourth signal and the third signal is larger than or equal to the energy value of the sum (R 0wR +L 0wR ) of the fourth signal and the third signal.
摘要:
An audio encoder (109) has a hierarchical encoding structure and generates a data stream comprising one or more audio channels as well as parametric audio encoding data. The encoder (109) comprises an encoding structure processor (305) which inserts decoder tree structure data into the data stream. The decoder tree structure data comprises at least one data value indicative of a channel split characteristic for an audio channel at a hierarchical layer of the hierarchical decoder structure and may specifically specify the decoder tree structures to be applied by a decoder. A decoder (115) comprises a receiver (401) which receives the data stream and a decoder structure processor (405) for generating the hierarchical decoder structure in response to the decoder tree structure data. A decode processor (403) then generates output audio channels from the data stream using the hierarchical decoder structure.
摘要:
A multi-channel audio encoder (10) for encoding a multi-channel audio signal (101), e.g. a 5.1 channel audio signal, into a spatial down-mix (102), e.g. a stereo signal, and associated parameters (104, 105). The encoder (10) comprises first and second units (110, 120). The first unit (110) encodes the multi-channel audio signal (101) into the spatial down-mix (102) and parameters (104). These parameters (104) enable a multi-channel decoder (20) to reconstruct the multi-channel audio signal (203) from the spatial down-mix (102). The second unit (120) generates, from the spatial down-mix (102), parameters (105) that enable the decoder to reconstruct the spatial down-mix (202) from an alternative down-mix (103), e.g. a so-called artistic down-mix that has been manually mixed in a sound studio. In this way, the decoder (20) can efficiently deal with a situation in which an alternative down-mix (103) is received instead of the regular spatial, down-mix (102). In the decoder (20), first the spatial down-mix (202) is reconstructed from the alternative down-mix (103) and the parameters (105). Next, the spatial down-mix (202) is decoded into the multi-channel audio signal (203).
摘要:
A multi-channel audio encoder (10) encodes an N-channel audio signal. A first unit (110) generates a first encoded M-channel signal, e.g. a spatial stereo down-mix, for the N-channel signal (N>M). Down-mixers(l 15, 116, 117) generate first enhancement data for the signal relative to the N-channel audio signal. A second M-channel signal, such as an artistic stereo mix, is generated for the N-channel signal. A processor (123) then generates second enhancement data for the second M-channel signal relative to the first M-channel signal. A second unit (120) generates an output signal comprising the second M-channel signal, the first enhancement data and the second enhancement data. The generator (123) can dynamically select between generating the second enhancement data as absolute enhancement data or as relative enhancement data relative to the second encoded M-channel signal. A decoder (20) can perform the inverse operation and can apply the second enhancement data as absolute or relative enhancement depending on an indication in the received bit-stream.
摘要:
Coding (1) an audio signal (x) comprises providing a respective set of sampled signal values for each of a plurality of sequential segments. The sampled signal values are analysed (130) to generate one or more sinusoidal components for each of the plurality of sequential segments. The sinusoidal components are linked across a plurality of sequential segments. Sinusoidal codes (CS) comprise tracks of linked sinusoidal components for each of the plurality of sequential segments. Each track comprises a frequency and amplitude for a sinusoidal component in a starting segment of a track whereas selected tracks include an indicator that no phase is included for said starting segment.
摘要:
There is described a multi-channel encoder (10) for processing input signals (300, 310, 320, 330, 340) conveyed in N input channels to generate corresponding output signals (480, 490) conveyed in M output channels together with complementary parametric data (370, 430, 450); M and N are integers wherein N>M. The encoder (10) includes a down-mixer for down-mixing the input signals (30, 310, 320, 330, 340) to generate the corresponding output signals (480, 490), the encoder also comprising an analyser for processing the input signals (300, 310, 320, 330, 340) to generate the parameter data (370, 430, 450), said parametric data describing mutual differences between the N channels of input signal to allow for regenerating during decoding one or more of the N channels of input signals from the M channels of output signal. Such an encoder (10) is capable of providing highly efficient data encoding and also of being backwards compatibility with relatively simpler decoders having fewer than N decoding output channels. The invention also concerns decoders compatible with such a multi-channel.
摘要:
A multi-channel audio encoder (10) for encoding a multi-channel audio signal (101), e.g. a 5.1 channel audio signal, into a spatial down-mix (102), e.g. a stereo signal, and associated parameters (104, 105). The encoder (10) comprises first and second units (110, 120). The first unit (110) encodes the multi-channel audio signal (101) into the spatial down-mix (102) and parameters (104). These parameters (104) enable a multi-channel decoder (20) to reconstruct the multi-channel audio signal (203) from the spatial down-mix (102). The second unit (120) generates, from the spatial down-mix (102), parameters (105) that enable the decoder to reconstruct the spatial down-mix (202) from an alternative down-mix (103), e.g. a so-called artistic down-mix that has been manually mixed in a sound studio. In this way, the decoder (20) can efficiently deal with a situation in which an alternative down-mix (103) is received instead of the regular spatial, down-mix (102). In the decoder (20), first the spatial down-mix (202) is reconstructed from the alternative down-mix (103) and the parameters (105). Next, the spatial down-mix (202) is decoded into the multi-channel audio signal (203).
摘要:
A method and a device for processing a stereo signal obtained from an encoder, which codes an N-channel audio signal into spatial parameters (P) and a stereo down-mix comprising first and second stereo signals (L 0 , R 0 ). A first signal and a third signal are added in order to obtain a first output signal (L 0w ), wherein the first signal QL 0wL ) comprises the first stereo signal (L 0 ) modified by a first complex function (g 1 ), and the third signal (L 0wR ) comprises the second stereo signal (R 0 ) modified by a third complex function (g 3 ). A second signal and a fourth signal are added to obtain a second output signal (R 0w ). The fourth signal (R 0wR ) comprises the second stereo signal (R 0 ) modified by a fourth complex function (g 4 ), and the second signal (R 0wL ) comprises the first stereo signal (L 0 ) modified by a second complex function (g 2 ). The complex functions (g 1 ,g 2 ,g 3 ,g 4 ) are functions of the spatial parameters (P) and are chosen such that an energy value of the difference (L 0wL -P 0wL ) between the first signal and the second signal is larger than or equal to the energy value of the sum (L 0wL +R 0wL ) of the first and the second signal and the energy value of the difference (R 0wR -L 0wR ) between the fourth signal and the third signal is larger than or equal to the energy value of the sum (R 0wR +L 0wR ) of the fourth signal and the third signal.