Encoding device and method, decoding device and method, and program

• US 10,236,015 B2
• Filed: 08/23/2017
• Issued: 03/19/2019
• Est. Priority Date: 10/15/2010
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Yamamoto, Yuki, Chinen, Toru
• Primary Examiner(s): Ton, David
• Application Number:
  US15/684,340
• Publication Number:
  US 20170352365A1
• Time in Patent Office: 573 Days
• CPC Class Codes: G10L 19/008 Multichannel audio signal coding or decoding using interchannel correlation to reduce redundancy, e.g. joint-stereo, intensity-coding or matrixing
• CPC Class Codes: G10L 19/0208 Subband vocoders
• CPC Class Codes: G10L 21/0388 Details of processing therefor
• CPC Class Codes: G10L 25/18 the extracted parameters being spectral information of each sub-band
• CPC Class Codes: G10L 25/21 the extracted parameters being power information

Abstract

The present invention relates to an encoding device and method, and a decoding device and method, and a program which enable music signals to be played with higher sound quality by expanding a frequency band.

A band pass filter divides an input signal into multiple subband signals, a feature amount calculating circuit calculates feature amount using at least any one of the divided multiple subband signals and the input signal, a high-frequency subband power estimating circuit calculates an estimated value of high-frequency subband power based on the calculated feature amount, and a high-frequency signal generating circuit generates a high-frequency signal component based on the multiple subband signals divided by the band pass filter and the estimated value of the high-frequency subband power calculated by the high-frequency subband power estimating circuit. A frequency band expanding device expands the frequency band of the input signal using the high-frequency signal component generated by the high-frequency signal generating circuit. The present invention may be applied to a frequency band expanding device, encoding device, decoding device, and so forth, for example.

Claims

1. A decoding device comprising:

a demultiplexing circuit configured to demultiplex input encoded data into low-frequency encoded data, coefficient information for obtaining a coefficient set, and smoothing information relating to smoothing;

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

a subband dividing circuit configured to divide the low-frequency signal into a plurality of subbands to generate a low-frequency subband signal for each of the subbands;

a feature amount calculating circuit configured to calculate a feature amount based on the low-frequency subband signals;

a smoothing circuit configured to subject the feature amount to smoothing based on the smoothing information indicating the number of frames used for the smoothing;

a generating circuit configured to generate a high-frequency signal based on the coefficient set obtained from the coefficient information, the feature amount subjected to smoothing, and the low-frequency subband signals; and

a synthesizing circuit configured to synthesize an output signal based on the low-frequency signal and the high-frequency signal and outputting the output signal.

2. A decoding method comprising:

demultiplexing, by processing circuitry, input encoded data into low-frequency encoded data, coefficient information for obtaining a coefficient set, and smoothing information relating to smoothing;

decoding, by the processing circuitry, the low-frequency encoded data to generate a low-frequency signal;

dividing, by the processing circuitry, the low-frequency signal into a plurality of subbands to generate a low-frequency subband signal for each of the subbands;

calculating, by the processing circuitry, a feature amount based on the low-frequency subband signals;

subjecting, by the processing circuitry, the feature amount to smoothing based on the smoothing information indicating the number of frames used for the smoothing;

generating, by the processing circuitry, a high-frequency signal based on the coefficient set obtained from the coefficient information, the feature amount subjected to smoothing, and the low-frequency subband signals; and

synthesizing, by the processing circuitry, an output signal based on the low-frequency signal and the high-frequency signal and outputting the output signal.

3. A non-transitory computer-readable medium storing computer-executable instructions that, when executed by a computer, cause the computer to execute processing comprising:

demultiplexing input encoded data into low-frequency encoded data, coefficient information for obtaining a coefficient set, and smoothing information relating to smoothing;

decoding the low-frequency encoded data to generate a low-frequency signal;

dividing the low-frequency signal into a plurality of subbands to generate a low-frequency subband signal for each of the subbands;

calculating a feature amount based on the low-frequency subband signals;

subjecting the feature amount to smoothing based on the smoothing information indicating the number of frames used for the smoothing;

generating a high-frequency signal based on the coefficient set obtained from the coefficient information, the feature amount subjected to smoothing, and the low-frequency subband signals; and

synthesizing an output signal based on the low-frequency signal and the high-frequency signal and outputting the output signal.