Selective scaling mask computation based on peak detection
AssigneeMotorola, Inc.
InventorsJames P. Ashley, Udar Mittal
Life of this patent
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Abstract
A set of peaks in a reconstructed audio vector Ŝ of a received audio signal is detected and a scaling mask ψ(Ŝ) based on the detected set of peaks is generated. A gain vector g* is generated based on at least the scaling mask and an index j representative of the gain vector. The reconstructed audio signal is scaled with the gain vector to produce a scaled reconstructed audio signal. A distortion is generated based on the audio signal and the scaled reconstructed audio signal. The index of the gain vector based on the generated distortion is output.
Claims15
An apparatus that decodes an audio signal, comprising:
- a gain vector decoder of an enhancement layer decoder that receives a reconstructed audio vector Ŝ and an index representative of a gain vector;
- wherein a gain selector of the gain vector decoder receives the index representative of the gain vector.
- a gain selector of the gain vector decoder that detects a set of peaks in the reconstructed audio vector, generates a scaling mask ψ(Ŝ) based on the detected set of peaks, and generates the gain vector g* based on at least the scaling mask and the index representative of the gain vector;
- a scaling unit of the gain vector decoder that scales the reconstructed audio vector with the gain vector to produce a scaled reconstructed audio signal.
A method for decoding an audio signal, the method comprising:
- receiving a reconstructed audio vector Ŝ and an index representative of a gain vector;
- detecting a set of peaks in the reconstructed audio vector;
- generating a scaling mask ψ(Ŝ) based on the detected set of peaks;
- generating the gain vector g* based on at least the scaling mask and the index representative of the gain vector;
- and
- scaling the reconstructed audio vector with the gain vector to produce a scaled reconstructed audio signal.
A method for encoding an audio signal, the method comprising:
- receiving an audio signal;
- encoding the audio signal to generate a reconstructed audio vector Ŝ;
- detecting a set of peaks in the reconstructed audio vector Ŝ of a received audio signal;
- generating a scaling mask ψ(Ŝ) based on the detected set of peaks;
- generating a plurality of gain vectors gj based on the scaling mask;
- scaling the reconstructed audio signal with the plurality of gain vectors to produce the plurality of scaled reconstructed audio signals;
- generating a plurality of distortions based on the audio signal and a plurality of scaled reconstructed audio signals;
- choosing a gain vector from the plurality of gain vectors based on the plurality of distortions;
- and
- outputting for at least one of transmitting and storing the index representative of the gain vector.
The method of 11, wherein the gain vector is chosen that corresponds with a minimum distortion of the plurality of distortions.
Dependencies are inferred from the claim text.