Method, device and system for enhancement layer signal encoding and decoding

• US 8,380,526 B2
• Filed: 05/19/2011
• Issued: 02/19/2013
• Est. Priority Date: 12/30/2008
• Status: Active Grant

• Current Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Inventors: Hu, Chen, Liu, Zexin, Chen, Longyin, Zhang, Qing, Xiao, Wei, Taddei, Herve Marcel, Miao, Lei
• Primary Examiner(s): Shah, Paras D
• Application Number:
  US13/111,834
• Publication Number:
  US 20110216839A1
• Time in Patent Office: 642 Days
• Field of Search: 704/219, 704/220, 704/221, 704/222, 704/223, 704/500
• US Class Current: 704/500
• 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
• CPC Class Codes: G10L 21/00 Speech or voice signal processing techniques to produce another audible or non-audible signal, e.g. visual or tactile, in order to modify its quality or its intelligibility G10L19/00 takes precedence

Abstract

A method, device and system for signal encoding and decoding are disclosed. The method includes: encoding a core layer signal to obtain a core layer signal code; selecting an enhancement sample point that requires enhancement layer signal encoding according to the core layer signal code and the number of bits that can be used by an enhancement layer; obtaining an enhancement layer signal code of the enhancement sample point; and outputting a bit stream, where the bit stream includes the core layer signal code and the enhancement layer signal code. In embodiments of the present invention, according to the number of bits that can be used by the enhancement layer, the enhancement sample point that requires enhancement layer signal encoding is selected; the enhancement layer signal of the selected enhancement sample point is encoded and decoded; when no sufficient bits are available for the enhancement layer, the enhancement quality of the core layer can be improved.

Claims

1. A signal encoding method, comprising:

encoding a core layer signal to obtain a core layer signal code;

determining a number of bits that can be used by an enhancement layer;

selecting, according to the core layer signal code and the determined number of bits, an enhancement sample point used in an enhancement layer signal encoding;

using the enhancement sample point to obtain an enhancement layer signal code; and

outputting a bit stream, wherein the bit stream comprises the core layer signal code and the enhancement layer signal code,

wherein before outputting the bit stream, the method further comprises;

performing local decoding for the enhancement layer signal code of the enhancement sample point;

performing local decoding for the code layer signal code;

modifying a core layer local decode signal according to the locally decoded enhancement layer signal; and

determining predicted values of core layer signals of subsequent sample points according to the modified core layer local decoded signal.

2. A signal encoding method, comprising:

encoding a core layer signal to obtain a core layer signal code;

determining a number of bits that can be used by an enhancement layer;

selecting, according to the core layer signal code and the determined number of bits, an enhancement sample point used in an enhancement layer signal encoding;

using the enhancement sample point to obtain an enhancement layer signal code; and

outputting a bit stream, wherein the bit stream comprises the core layer signal code and the enhancement layer signal code,

wherein N indicates a total number of sample points and n indicates a sequence number for each of a sample point, wherein 0≦

n≦

N−

1, and

wherein the step of selecting the enhancement sample point used in the enhancement layer signal encoding comprises;

obtaining a moving average value of a specified signal of the sample point numbered n, wherein the moving average value is an average value of absolute values of specified signals of sample points numbered less than n; and

determining whether the sample point numbered n is the enhancement sample point used in the enhancement layer signal encoding according to the moving average value.

3. A signal encoding method, comprising:

encoding a core layer signal to obtain a core layer signal code;

determining a number of bits that can be used by an enhancement layer;

selecting, according to the core layer signal code and the determined number of bits, an enhancement sample point used in an enhancement layer signal encoding;

using the enhancement sample point to obtain an enhancement layer signal code; and

outputting a bit stream, wherein the bit stream comprises the core layer signal code and the enhancement layer signal code,

wherein EN indicates the number of enhancement sample points, and

wherein the step of selecting the enhancement sample point used in the enhancement layer signal encoding comprises;

calculating an average value of absolute values of specified signals of all sample points; and

from a first sample point, sequentially selecting sample points where the absolute values of the specified signals are larger than the average value as enhancement sample points used in the enhancement layer signal encoding, until the number of enhancement sample points is equal to EN.

4. The signal encoding method according to claim 3, wherein the specified signal is a residual signal after local decoding of a core layer, or a signal after local decoding of the core layer, or a signal after local decoding of the core layer and noise shaping, or a residual signal after local decoding of the core layer and noise shaping.

5. A signal encoding method, comprising:

encoding a core layer signal to obtain a core layer signal code;

determining a number of bits that can be used by an enhancement layer;

selecting, according to the core layer signal code and the determined number of bits, an enhancement sample point used in an enhancement layer signal encoding;

using the enhancement sample point to obtain an enhancement layer signal code; and

outputting a bit stream, wherein the bit stream comprises the core layer signal code and the enhancement layer signal code,

wherein EN indicates the number of enhancement sample points, and

wherein the step of selecting the enhancement sample point used in the enhancement layer signal encoding comprises;

selecting a sample point at intervals of one sample point as an enhancement sample point used in the enhancement layer signal encoding;

when the number of enhancement sample points is larger than EN, from a specified sample point among the enhancement sample points, removing enhancement sample points, until the number of enhancement sample points is equal to EN; and

when the number of enhancement sample points is smaller than EN, from a first unselected sample point, sequentially selecting unselected sample points as enhancement sample points, until the number of enhancement sample points is equal to EN.

6. A signal decoding method, comprising:

receiving a bit stream, wherein the bit stream comprises a core layer signal code and an enhancement layer signal code;

determining a number of bits used by an enhancement layer;

selecting, according to the core layer signal code and the determined number of bits, an enhancement sample point used in an enhancement layer signal decoding;

decoding the enhancement layer signal code of the enhancement sample point to obtain an enhancement layer signal; and

obtaining a modified core layer signal according to the enhancement layer signal and the bit stream,

wherein N indicates a total number of sample points and n indicates a sequence number for each sample point, wherein 0≦

n≦

N−

1, and

wherein the step of selecting the enhancement sample point used in the enhancement layer signal decoding comprises;

obtaining a moving average value of a specified signal of the sample point numbered n, wherein the moving average value is an average value of absolute values of specified signals of sample points numbered less than n; and

determining whether the sample point numbered n is the enhancement sample point used in the enhancement layer signal decoding according to the moving average value.

7. A signal decoding method, comprising:

receiving a bit stream, wherein the bit stream comprises a core layer signal code and an enhancement layer signal code;

determining a number of bits used by an enhancement layer;

selecting, according to the core layer signal code and the determined number of bits, an enhancement sample point used in an enhancement layer signal decoding;

decoding the enhancement layer signal code of the enhancement sample point to obtain an enhancement layer signal; and

obtaining a modified core layer signal according to the enhancement layer signal and the bit stream,

wherein EN indicates the number of enhancement sample points, and

wherein the step of selecting the enhancement sample point used in the enhancement layer signal decoding comprises;

calculating an average value of absolute values of specified signals of all sample points; and

from a first sample point, sequentially selecting sample points where the absolute values of the specified signals are larger than the average value as enhancement sample points that require enhancement layer signal decoding, until the number of enhancement sample points is equal to EN.

8. A signal decoding method, comprising:

receiving a bit stream, wherein the bit stream comprises a core layer signal code and an enhancement layer signal code;

determining a number of bits used by an enhancement layer;

selecting, according to the core layer signal code and the determined number of bits, an enhancement sample point used in an enhancement layer signal decoding;

decoding the enhancement layer signal code of the enhancement sample point to obtain an enhancement layer signal; and

obtaining a modified core layer signal according to the enhancement layer signal and the bit stream,

wherein EN indicates the number of enhancement sample points, and

wherein the step of selecting the enhancement sample point used in the enhancement layer signal decoding comprises;

selecting a sample point at intervals of one sample point as an enhancement sample point used in the enhancement layer signal decoding;

when the number of enhancement sample points is larger than EN, from a specified sample point among the enhancement sample points, removing enhancement sample points, until the number of enhancement sample points is equal to EN; and

when the number of enhancement sample points is smaller than EN, from a first unselected sample point, sequentially selecting unselected sample points as enhancement sample points, until the number of enhancement sample points is equal to EN.