Signal processing apparatus and signal processing method, encoder and encoding method, decoder and decoding method, and program

• US 10,546,594 B2
• Filed: 02/15/2019
• Issued: 01/28/2020
• Est. Priority Date: 04/13/2010
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Yamamoto, Yuki, Chinen, Toru, Honma, Hiroyuki, Mitsufuji, Yuhki
• Primary Examiner(s): Patel, Yogeshkumar
• Application Number:
  US16/276,936
• Publication Number:
  US 20190180768A1
• Time in Patent Office: 347 Days
• CPC Class Codes: G10L 19/0204 using subband decomposition
• CPC Class Codes: G10L 19/0208 Subband vocoders
• CPC Class Codes: G10L 19/167 Audio streaming, i.e. formatting and decoding of an encoded audio signal representation into a data stream for transmission or storage purposes
• CPC Class Codes: G10L 21/038 using band spreading techniques
• CPC Class Codes: G10L 21/0388 Details of processing therefor

Abstract

The present invention relates to a signal processing apparatus and a signal processing method, an encoder and an encoding method, a decoder and a decoding method, and a program capable of reproducing music signal having a better sound quality by expansion of frequency band.

An encoder sets an interval including 16 frames as interval section to be processed, outputs high band encoded data for obtaining the high band component of an input signal and low band encoded data obtained by encoding the low band signal of the input signal for each section to be processed. In this case, for each frame, a coefficient used in estimation of the high band component is selected and the section to be processed is divided into continuous frame segments including continuous frames from which the coefficient with the same section to be processed is selected. In addition, high band encoded data is produced which includes data including information indicating a length of each continuous frame segment, information indicating the number of continuous frame segments included in the section to be processed and a coefficient index indicating the coefficient selected in each continuous frame segment. The present invention is applicable to the encoder.

Claims

1. A decoding device, comprising:

a demultiplexing circuit configured to demultiplex input encoded data into at least low frequency encoded data and an index indicating an estimating coefficient;

a low frequency decoding circuit configured to decode said low frequency encoded data to generate a low frequency signal;

a sub-band dividing circuit configured to divide a band of said low frequency signal into a plurality of low frequency sub-bands to generate a low frequency sub-band signal for each of said plurality of low frequency sub-bands; and

a generating circuit configured to generate a high frequency signal based on said index and said low frequency sub-band signals,

wherein said generating circuit comprises circuitry configured to;

calculate a plurality of feature amounts, each of which expresses a feature of a respective low frequency sub-band signal;

calculate, for each of a plurality of high-frequency sub-bands making up a band of said high frequency signal, a high frequency sub-band power by multiplying said feature amount and said estimating coefficient for each of said plurality of high frequency sub-bands and summing said multiplied feature amounts and estimating coefficients; and

generate said high frequency signal based on said high frequency sub-band powers and said low frequency sub-band signals.

2. A signal processing method, comprising:

demultiplexing input encoded data into at least low frequency encoded data and an index indicating an estimating coefficient;

decoding said low frequency encoded data to generate a low frequency signal;

dividing a band of said low frequency signal into a plurality of low frequency sub-bands to generate a low frequency sub-band signal for each of said low frequency sub-bands; and

generating a high frequency signal based on said index and said low frequency sub-band signals, wherein generating said high frequency signal comprises;

calculating a plurality of feature amounts, each of which expresses a feature of said low frequency sub-band signal;

calculating, for each of a plurality of high-frequency sub-bands making up a band of said high frequency signal, a high frequency sub-band power by multiplying said feature amount and said estimating coefficient for each of said plurality of high frequency sub-bands and summing said multiplied feature amounts and estimating coefficients; and

generating said high frequency signal based on said high frequency sub-band powers and said low frequency sub-band signals.

3. A non-transitory computer readable medium encoded with a plurality of instructions that, when executed by at least one computer processor, perform a method comprising:

demultiplexing input encoded data into at least low frequency encoded data and an index indicating an estimating coefficient;

decoding said low frequency encoded data to generate a low frequency signal;

dividing a band of said low frequency signal into a plurality of low frequency sub-bands to generate a low frequency sub-band signal for each of said low frequency sub-bands; and

generating a high frequency signal based on said index and said low frequency sub-band signals, wherein generating said high frequency signal comprises;

calculating a plurality of feature amounts, each of which expresses a feature of said low frequency sub-band signal;

calculating, for each of a plurality of high-frequency sub-bands making up a band of said high frequency signal, a high frequency sub-band power by multiplying said feature amount and said estimating coefficient for each of said plurality of high frequency sub-bands and summing said multiplied feature amounts and estimating coefficients; and

generating said high frequency signal based on said high frequency sub-band powers and said low frequency sub-band signals.