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ETSI ES 201 980 V4.1.2 (2017-04) |
Begin
Generate frameError Yes 
Concealing control
data
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No |
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prevFrame- |
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timeCompensate- |
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coupling = |
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Yes |
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ErrorFlag |
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FirstEnvelope |
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prevCoupling |
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No
addConcealing-
EnvelopeData
deltaToLinearPCMEnvelopeDecoding
deltaToLinearPCMEnvelope-
Decoding
check data
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requantise- |
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error |
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return |
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flag |
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EnvelopeData |
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Figure 6: SBR error concealment overview
inter-TES (Temporal Envelope Shaping)
bs_temp_shape and bs_inter_temp_shape_mode are assumed to be zero in concealed frames.
5.3.3.4MPS212 parametric stereo
MPS212 parametric stereo concealment is based on the fact that the stereo image is quasi-stationary. The concealment strategy keeps the MPS212 parametric stereo settings from the last valid frame until a new set of MPS212 parametric stereo settings can be decoded from a valid frame.
5.3.3.5MDCT based Complex Prediction
Similar to MPS212 parametric stereo (see clause 5.3.3.4), the Complex Prediction concealment is based on the fact that the stereo image is quasi-stationary. The concealment strategy keeps the Complex Prediction settings from the last valid frame until a new set of Complex Prediction settings can be decoded from a valid frame.
5.3.3.6Forward Aliasing Cancellation
The Forward Aliasing Cancellation signal part is assumed to be zero in concealed frames. During recovery the Forward Aliasing Cancellation data (fac_data()) is ignored if present.
5.3.4xHE-AAC + MPS
The standard UsacExtElement() is used to carry MPEG Surround as defined by ISO/IEC 23003-3 [11]. The corresponding static part of the configuration is signalled via SDC data entity type 9 in the codec specific configuration field.
ETSI