Method and device for pulse encoding, method and device for pulse decoding

• US 10,026,412 B2
• Filed: 05/11/2016
• Issued: 07/17/2018
• Est. Priority Date: 06/19/2009
• Status: Active Grant

• Current Assignee: Top Quality Telephony LLC
• Original Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Inventors: Ma, Fuwei, Zhang, Dejun, Xie, Minjie, Zhang, Qing
• Primary Examiner(s): Baker, Matthew H
• Application Number:
  US15/151,508
• Publication Number:
  US 20160329059A1
• Time in Patent Office: 797 Days
• CPC Class Codes: G10L 19/002 Dynamic bit allocation for perceptual audio coders G10L19/032
• CPC Class Codes: G10L 19/04 using predictive techniques
• CPC Class Codes: G10L 19/10 the excitation function being a multipulse excitation
• CPC Class Codes: G10L 19/113 Regular pulse excitation
• CPC Class Codes: G10L 19/12 the excitation function being a code excitation, e.g. in code excited linear prediction [CELP] vocoders
• CPC Class Codes: G10L 2019/0016 Codebook for LPC parameters
• CPC Class Codes: H03M 7/30 Compression speech analysis-synthesis for redundancy reduction G10L19/00; for image communication H04N; Expansion; Suppression of unnecessary data, e.g. redundancy reduction
• CPC Class Codes: H03M 7/40 Conversion to or from variable length codes, e.g. Shannon-Fano code, Huffman code, Morse code
• CPC Class Codes: H03M 7/4068 Parameterized codes

Abstract

The present application discloses a pulse encoding method for use by a voice encoder. An initial number of coding bits is determined according to number of pulses in an input signal. An index value is calculated according to information of the pulses in the input signal. The index value is compared with an adjustment threshold value. If the index value is smaller than the adjustment threshold value, the index value is encoded using a reduced number of encoding bits. If the index value is not smaller than the adjustment threshold value, the index value plus an offset value is encoded using the initial number of encoding bits. The reduced number of encoding bits is smaller than the initial number of encoding bits, and the offset value is greater than or equal to the adjustment threshold value.

Claims

1. A audio signal encoding method, comprising:

with an audio signal encoder,

receiving an input audio signal;

extracting information of pulses on a track of the audio signal, wherein the information of the pulses comprises;

number of the pulses, positions of the pulses on the track, and symbols of the pulses;

determining an index value corresponding to the information of the pulses;

determining an initial number of bits for encoding the index value;

comparing the index value with an adjustment threshold value;

when the index value is smaller than the adjustment threshold value, encoding the index value using a reduced number of bits, or

when the index value is not smaller than the adjustment threshold value, encoding the index value plus an offset value using the initial number of bits; and

transmitting the encoded index value to a decoding side,

wherein the reduced number of bits is smaller than the initial number of bits, and the initial number of bits and the reduced number of bits are both positive integers,

and wherein the offset value is greater than or equal to the adjustment threshold value.

2. The audio signal encoding method according to claim 1, wherein the initial number of bits is obtained by rounding up a theoretical value of bits required to encode the index value.

3. The audio signal encoding method according to claim 2, further comprising:

determining a value range corresponding to the initial number of bits;

determining a codebook space corresponding to the number of the pulses and a value range of the codebook space, wherein the value range of the codebook space is smaller than the value range corresponding to the initial number of bits; and

setting the adjustment threshold value as smaller than or equal to a difference between the value range corresponding to the initial number of bits and the value range of the codebook space.

4. A non-transitory computer readable medium having computer executable program codes stored thereon for use by an audio signal encoder, wherein the program codes comprise instructions for:

receiving an input audio signal;

extracting information of pulses on a track of the audio signal, wherein the information of the pulses comprises;

number of the pulses, positions of the pulses on the track, and symbols of the pulses;

determining an index value corresponding to the information of the pulses;

determining an initial number of bits for encoding the index value;

comparing the index value with an adjustment threshold value;

when the index value is smaller than the adjustment threshold value, encoding the index value using a reduced number of bits, or

when the index value is not smaller than the adjustment threshold value, encoding the index value plus an offset value using the initial number of bits; and

transmitting the encoded index value to a decoding side,

wherein the reduced number of bits is smaller than the initial number of bits, and the initial number of bits and the reduced number of bits are both positive integers,

and wherein the offset value is greater than or equal to the adjustment threshold value.

5. The non-transitory computer readable medium according to claim 4, wherein the initial number of bits is obtained by rounding up a theoretical value of bits required to encode the index value.

6. The non-transitory computer readable medium according to claim 5, wherein the program codes further comprise instructions for:

determining a value range corresponding to the initial number of bits;

determining a codebook space corresponding to the number of the pulses and a value range of the codebook space, wherein the value range of the codebook space is smaller than the value range corresponding to the initial number of bits; and

setting the adjustment threshold value as smaller than or equal to a difference between the value range corresponding to the initial number of bits and the value range of the codebook space.