Encoding device, encoding method, and program

• US 9,437,197 B2
• Filed: 03/23/2012
• Issued: 09/06/2016
• Est. Priority Date: 03/31/2011
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Honma, Hiroyuki, Chinen, Toru, Yamamoto, Yuki, Hatanaka, Mitsuyuki
• Primary Examiner(s): Tieu, Benny Q
• Assistant Examiner(s): Chacko, Sunil
• Application Number:
  US14/006,148
• Publication Number:
  US 20140006037A1
• Time in Patent Office: 1,628 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: G10L 19/002 Dynamic bit allocation for perceptual audio coders G10L19/032
• 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 19/0204 using subband decomposition
• CPC Class Codes: G10L 19/24 Variable rate codecs, e.g. for generating different qualities using a scalable representation such as hierarchical encoding or layered encoding

Abstract

This technology relates to an encoding device, an encoding method, and a program capable of improving audio quality and more efficiently encoding audio. A first high-frequency encoding circuit encodes a high-frequency range based on a low-frequency subband signal and a high-frequency subband signal and obtains a high-frequency code amount. A low-frequency encoding circuit encodes a low-frequency signal with a code amount determined by the high-frequency code amount and a low-frequency decoding circuit decodes the encoded low-frequency signal. A subband dividing circuit divides a decoded low-frequency signal obtained by decoding into decoded low-frequency subband signals of a plurality of subbands and a second high-frequency encoding circuit generates a high-frequency code string such that a code amount of the high-frequency code string for obtaining a high-frequency component is not larger than the high-frequency code amount based on the decoded low-frequency subband signals and the high-frequency subband signals. The present invention is applicable to the encoding device.

Claims

1. An encoding device, comprising:

a first high-frequency encoding circuit which calculates a high-frequency code amount being a code amount of a high-frequency code string for obtaining a high-frequency component based on a low-frequency component and the high-frequency component of an input signal;

a low-frequency encoding circuit which encodes the low-frequency component of the input signal based on the high-frequency code amount calculated by the first high-frequency encoding circuit to generate a low-frequency code string;

a low-frequency decoding circuit which decodes the low-frequency code string;

a second high-frequency encoding circuit which generates the high-frequency code string based on a decoded low-frequency component obtained by decoding the low-frequency code string and the high-frequency component such that the code amount of the high-frequency code string is not larger than the high-frequency code amount;

a multiplexing circuit which multiplexes the low-frequency code string and the high-frequency code string to generate an output code string; and

a delay circuit which delays the high-frequency code amount, the decoded low-frequency component, and the high-frequency component input to the second high-frequency encoding circuit.

2. The encoding device according to claim 1, wherein

the first high-frequency encoding circuit calculates the high-frequency code amount based on low-frequency subband signals of a plurality of subbands composing the low-frequency component and high-frequency subband signals of a plurality of subbands composing the high-frequency component, and

the second high-frequency encoding circuit generates the high-frequency code string based on decoded low-frequency subband signals of a plurality of subbands composing the decoded low-frequency component and the high-frequency subband signals.

3. The encoding device according to claim 1, further comprising:

a code amount adjusting circuit which, when the code amount of the high-frequency code string obtained by the second high-frequency encoding circuit is smaller than the high-frequency code amount, makes a difference between the code amount of the high-frequency code string and the high-frequency code amount a surplus code amount capable of being used in next and subsequent processes and controls storage of the surplus code amount.

4. The encoding device according to claim 3, wherein

the surplus code amount is used for adjusting the code amount of at least any of the high-frequency code string and the low-frequency code string.

5. An encoding method comprising:

calculating a high-frequency code amount being a code amount of a high-frequency code string for obtaining a high-frequency component based on a low-frequency component and the high-frequency component of an input signal;

encoding the low-frequency component of the input signal based on the high-frequency code amount to generate a low-frequency code string;

decoding the low-frequency code string;

delaying the high-frequency code amount, a decoded low-frequency component obtained by decoding the low-frequency code string and the high-string is not larger than the high-frequency code amount, and the high-frequency component;

generating the high-frequency code string based on the decoded low-frequency component and

multiplexing the low-frequency code string and the high-frequency code string to generate an output code string.

6. A non-transitory computer readable storage device encoded with instructions that, when executed by at least one processor, cause the at least one processor to perform a method comprising acts of:

calculating a high-frequency code amount being a code amount of a high-frequency code string for obtaining a high-frequency component based on a low-frequency component and the high-frequency component of an input signal;

encoding the low-frequency component of the input signal based on the high-frequency code amount to generate a low-frequency code string;

decoding the low-frequency code string;

delaying the high-frequency code amount, a decoded low-frequency component obtained by decoding the low-frequency code string and the high-frequency component such that the code amount of the high-frequency code string is not larger than the high-frequency code amount and the high-frequency component;

generating the high-frequency code string based on the decoded low-frequency component; and

multiplexing the low-frequency code string and the high-frequency code string to generate an output code string.