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Mdct-based complex prediction stereo coding Invention relates to means of stereo encoding and decoding using complex prediction in the frequency domain. A decoding method for obtaining an output stereo signal from an input stereo signal encoded by complex prediction coding and comprising first frequency-domain representations of two input channels, comprises the upmixing steps of: (i) computing a second frequency-domain representation of a first input channel; and (ii) computing an output channel based on the first and second frequency-domain representations of the first input channel, the first frequency-domain representation of the second input channel and a complex prediction coefficient. |
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Method and apparatus for selective signal coding based on core encoder performance In a selective signal encoder, an input signal is first encoded (1004)using a core layer encoder to produce a core layer encoded signal. The core layer encoded signal is decoded (1006) to produce a reconstructed signal, and an error signal is generated (1008) as the difference between the reconstructed signal and the input signal. The reconstructed signal is compared (1010) with the input signal. One of two or more enhancement layer encoders is selected (1014, 1016) depending on the comparison and is used to encode the error signal. The core layer encoded signal, the enhancement layer encoded signal and a selection indicator are output (1018) to a channel (e.g., for transmission or storage). |
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Encoding device, decoding device and method Disclosed is an encoding device which can accurately specify a band having a large error among all bands by using a small calculation amount. The device includes: a first position identification unit (201) which uses a first layer error conversion coefficient indicating an error of decoding signal for an input signal so as to search for a band having a large error in a relatively wide bandwidth in all the bands of the input signal and generates first position information indicating the identified band; a second position identification unit (202) which searches for a target frequency band having a large error in a relatively narrow bandwidth in the band identified by the first position identification unit (201) and generates second position information indicating the identified target frequency band; and an encoding unit (203) which encodes a first layer decoding error conversion coefficient contained in the target frequency band. The first position information, the second position information, and the encoding unit are transmitted to a communication partner. |
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Audio encoder and audio decoder for encoding frames presented in form of audio signal samples Audio encoder (100) for encoding frames presented in form of audio signal samples to obtain encoded frames, wherein a frame consists of a plurality of time domain audio signals, including a predictive coding analysis stage (110) and determining information on coefficients of a synthesis filter and prediction domain frame information based on a frame of audio samples. The audio encoder (100) further includes a domain converter (120) for converting a frequency domain audio sample frame and obtaining a frame spectrum and an encoding domain computer (130) for making a decision on encoded data for a frame based on information on coefficients and information on a prediction domain frame, or based on the frame spectrum. The audio encoder (100) includes a controller (140) for determining information on a switching coefficient for cases when the encoding domain computer decides that encoded data of the current frame are based on information on coefficients and information on a prediction domain frame, and [for cases] when data of a previous frame were encoded based on the spectrum of the previous frame and redundancy reducing encoder (150) for encoding information on the prediction domain frame, information on coefficients, information on the switching coefficient and/or frame spectrum. |
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When a frame immediately preceding a target encoding frame to be encoded by a first encoding unit operating according to a linear predictive coding scheme is encoded by a second encoding unit operating according to a coding scheme different from the linear predictive coding scheme, the target encoding frame can be encoded according to the linear predictive coding scheme by initialising the internal state of the first encoding unit. Consequently, encoding processing performed according to a plurality of coding schemes including the linear predictive coding scheme and a coding scheme different from the linear predictive coding scheme can be realised. |
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When a frame immediately preceding a target encoding frame to be encoded by a first encoding unit operating according to a linear predictive coding scheme is encoded by a second encoding unit operating according to a coding scheme different from the linear predictive coding scheme, the target encoding frame can be encoded according to the linear predictive coding scheme by initialising the internal state of the first encoding unit. Consequently, encoding processing performed according to a plurality of coding schemes including the linear predictive coding scheme and a coding scheme different from the linear predictive coding scheme can be realised. |
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Method is proposed to compensate for losses of sound signal frames in the MDCT area, including: a step a, during which, when the current lost frame is the P frame, a set of forecast frequencies is received, for each frequency in this set they use phases and amplitudes of multiple frames before the (P-1) frame in the area MDCT-MDST to forecast phase and amplitude of the P frame, and the forecast phase and amplitude are used for production of MDCT coefficients of the P frame, corresponding to each frequency; a step b, at which for frequencies outside the set of forecast frequencies the MDCT coefficients of multiple frames before the P frame are used for calculation of MDCT coefficient values of P frame on these frequencies; a step c, during which they perform inverse modified discrete cosine transformation (IMDCT) for MDCT coefficients of the P frame at all frequencies for production of the signal in the time area for the P frame. Also a compensator is proposed for losses of frames. The invention has advantages of no delay, low volume of calculations, low volume of memory space and simplicity of realisation. |
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When a frame immediately preceding an encoding target frame to be encoded by a first encoding unit operating according to a linear predictive coding scheme is encoded by a second encoding unit operating according to a coding scheme different from the linear predictive coding scheme, the encoding target frame can be encoded according to the linear predictive coding scheme by initialising the internal state of the first encoding unit. Therefore, encoding processing performed according to a plurality of coding schemes including the linear predictive coding scheme and a coding scheme different from the linear predictive coding scheme can be realised. |
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Improved temperature compensation of multivariate pressure gage Invention relates to adjustment of production processes and may be used in control over various equipment. Proposed process fluid pressure gage 10 comprises electronic module 18 and sensor module 222. The latter is connected with the former. Process fluid temperature sensor is connected with process fluid pressure sensor. Differential pressure sensor 228 is arranged inside sensor module 22 and communicated with multiple fluid pressure inputs. Static pressure sensor 230 is also arranged inside sensor module 22 and communicated with, at least, one process fluid pressure input. First temperature sensor 232 is arranged inside sensor module 222 and configured to indicate temperature of differential pressure sensor 228. Second temperature sensor 234 is arranged inside sensor module 222 and configured to indicate temperature of static pressure sensor 230. |
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Subband voice codec with multi-stage codebooks and redudant coding Techniques and tools related to coding and decoding of audio information are described. For example, redundant coded information for decoding a current frame includes signal history information associated with only a portion of a previous frame. As another example, redundant coded information for decoding a coded unit includes parametres for a codebook stage to be used in decoding the current coded unit only if the previous coded unit is not available. As yet another example, coded audio units each include a field indicating whether the coded unit includes main encoded information representing a segment of an audio signal, and whether the coded unit includes redundant coded information for use in decoding main encoded information. |
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Method for vector quantisation of linear prediction parametres Result is achieved by introducing linear prediction parametres of a predictor into a differential vector quantiser with adaptation to the voice pitch: when classifying the frame of a speech signal as stationary vocalised, the prediction scheme with adaptation to the voice pitch is selected. Calculation of the prediction vector involves calculation of the prediction error vector through prediction with adaptation to the voice pitch. Selection of one of multiple scaling schemes involves selection of scaling coefficient equal to one. |
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Method and device for introducing low-frequency emphasis when compressing sound based on acelp/tcx Invention relates to a method of introducing low frequency emphasis into the spectrum of a sound signal converted in the frequency domain and containing conversion coefficients grouped into a row of units in which maximum intensity for one unit is calculated and the position index of the unit with maximum intensity is determined. A coefficient is calculated for each unit having position index less than the position index of the unit with maximum intensity, and amplification is determined for each unit from the coefficient and is applied to conversion coefficients of the unit. |
Another patent 2513215.