A method, device, equipment and storage medium for extending the frequency band of an audio signal

Abstract

A method, device, equipment and storage medium for extending the frequency band of an audio signal, belonging to the field of communication technology. The method comprises: receiving a bit stream sent by an encoding device, decoding the bit stream to obtain a decoded audio frequency domain signal; in response to the highest frequency point of the bit allocation of the audio frequency domain signal being lower than the starting frequency point of the preset bandwidth extension band, or the frequency band of the bit allocation of the audio frequency domain signal being smaller than the preset bandwidth extension starting band, predicting the spectrum signal between the highest frequency point of the bit allocation and the highest frequency point of the preset bandwidth extension band based on the spectrum signal within the predetermined frequency band range or the predetermined frequency point range in the audio frequency domain signal. The method can avoid the situation where "there is no spectrum signal between the highest frequency point of the bit allocation and the starting frequency point of the preset bandwidth extension band", ensure the balance of high and low frequency energy within the frame, avoid the mechanical feeling caused by spectrum holes, and improve the quality of reconstructed audio.

Description

Technical Field

[0001] The present disclosure relates to the field of communication technology, and in particular to an audio signal frequency band expansion method / device / equipment and a storage medium. Background Art

[0002] In order to reduce the resources occupied during the transmission of audio signals, the signal transmitter usually converts the audio signal from a time domain signal to a frequency domain signal when transmitting the audio signal, and then uses an encoding device to compress and encode the frequency domain signal before transmitting it. And after the signal receiver receives the encoded signal, it needs to first use a decoding device to perform a decoding operation to reconstruct the audio frequency domain signal, and then convert the reconstructed audio frequency domain signal into a time domain signal to obtain a reconstructed audio time domain signal.

[0003] In the related art, since limited quantization bits cannot meet the quantization of all audio signals to be quantized at a low bit rate, the encoding device uses most of the bits to finely quantize the low-spectrum signals in the relatively important audio signals, that is, the quantization parameters of the low-spectrum signals occupy most of the bits; and only a small number of bits are used to roughly quantize the high-spectrum signals in the encoded audio signals to obtain the frequency domain envelope of the high-spectrum signals, and then the frequency domain envelope of the high-spectrum signals and the quantization parameters of the low-spectrum signals are sent to the decoding device in the form of a bit stream. And, when decoding, the decoding device first decodes and multiplexes the received bit stream to decode and obtain the quantization parameters of the low-spectrum signals and the frequency domain envelope of the high-spectrum signals, and then restores the low-spectrum signals according to the quantization parameters of the low-spectrum signals obtained by decoding, and then uses the band extension technology based on the quantization parameters of the low-spectrum signals obtained by decoding to obtain the high-spectrum signals above the starting frequency point of the preset bandwidth extension band.

[0004] As can be seen from the above content, the decoding device involves the following concepts in the process of decoding audio signals, namely: bandwidth extension band (i.e., extended high frequency band, specifically: the band between the starting frequency point of the preset bandwidth extension band and the highest frequency point of the preset bandwidth extension band), bit-allocated frequency point (i.e., the frequency point corresponding to the encoded low-spectrum signal), and the highest frequency point with bit allocation, the highest frequency point with bit allocation is: the highest frequency point of the encoded low-spectrum signal, in other words, no low-spectrum signal is decoded above the highest frequency point with bit allocation, wherein the frequency band above the highest frequency point with bit allocation can be called a high frequency band, and the frequency band below the highest frequency point with bit allocation can be called a low frequency band. And, there are two distribution modes between the above-mentioned bandwidth extension band and the highest frequency point with bit allocation. Figure 1a-1b A distribution relationship diagram between a bandwidth extension frequency band and the highest frequency point with bit allocation provided by an embodiment of the present disclosure. Figure 1a As shown in FIG. 1 , the starting frequency of the bandwidth extension band may be higher than the highest frequency with bit allocation. And, as Figure 1bAs shown, the starting frequency point of the bandwidth extension band may be lower than the highest frequency point with bit allocation.

[0005] Regarding the above Figure 1a In terms of the above, since the decoding method in the related art only predicts the high frequency spectrum signal corresponding to the bandwidth extension band, the decoding method in the related art will make Figure 1a There is no corresponding spectrum signal in the area from the highest frequency point with bit allocation to the starting frequency point of the bandwidth extension band, which will cause imbalance of high and low frequency energy in the frame, and further cause the technical problem of "mechanical sense caused by spectrum holes", reducing the quality of reconstructed audio. Summary of the invention

[0006] The audio signal frequency band expansion method / device / equipment and storage medium proposed in the present disclosure are intended to solve the technical problems of imbalanced high and low frequency energy within a frame, mechanical feeling caused by spectrum holes, and low quality of reconstructed audio caused by related technical methods.

[0007] In a first aspect, an embodiment of the present disclosure provides a method for extending a frequency band of an audio signal, the method being performed by a decoding device, comprising:

[0008] Receiving a bit stream sent by an encoding device, and decoding the bit stream to obtain a decoded audio frequency domain signal;

[0009] In response to the highest frequency point of bit allocation in the audio frequency domain signal being lower than the starting frequency point of a preset bandwidth extension band, or the frequency band of bit allocation in the audio frequency domain signal being smaller than the preset bandwidth extension starting frequency band, a spectrum signal between the highest frequency point of bit allocation and the highest frequency point of the preset bandwidth extension band is predicted based on a spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal.

[0010] In the present disclosure, a method for extending the frequency band of an audio signal is provided, wherein a decoding device receives a bit stream sent by an encoding device, and decodes the bit stream to obtain a decoded audio frequency domain signal. In addition, in response to the highest frequency point of the bit allocation of the audio frequency domain signal being lower than the starting frequency point of the preset bandwidth extension band, or the frequency band of the bit allocation of the audio frequency domain signal being smaller than the preset bandwidth extension starting frequency band, the decoding device predicts the spectrum signal between the highest frequency point of the bit allocation and the highest frequency point of the preset bandwidth extension band based on the spectrum signal within the predetermined frequency band range or the predetermined frequency point range in the audio frequency domain signal. It can be seen from this that in the present disclosure, when the highest frequency point of the bit allocation of the audio frequency domain signal is lower than the starting frequency point of the preset bandwidth extension band, or when the frequency band of the bit allocation of the audio frequency domain signal is smaller than the preset bandwidth extension starting band, when predicting the spectrum signal in the present disclosure, what is specifically predicted is the spectrum signal between the highest frequency point of the bit allocation and the highest frequency point of the preset bandwidth extension band, rather than only predicting the spectrum signal of the bandwidth extension band. This will result in a predicted spectrum signal corresponding to the highest frequency point of the bit allocation and the starting frequency point of the preset bandwidth extension band, and avoid the situation where "there is no spectrum signal between the highest frequency point of the bit allocation and the starting frequency point of the preset bandwidth extension band", thereby ensuring the balance of high and low frequency energy within the frame, and avoiding the mechanical feel caused by spectrum holes, thereby improving the quality of reconstructed audio.

[0011] Optionally, in an embodiment of the present disclosure, the method further includes:

[0012] The starting frequency point and the highest frequency point of the preset bandwidth extension band are determined based on the encoding rate of the encoding device and the frequency band range required for encoding the audio signal.

[0013] Optionally, in an embodiment of the present disclosure, the frequencies in the predetermined frequency band range or the predetermined frequency point range are all lower than the highest frequency point with bit allocation.

[0014] Optionally, in an embodiment of the present disclosure, predicting a spectrum signal between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension band based on a spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal includes:

[0015] Taking the highest frequency point with bit allocation as the starting point, or taking the highest frequency point of the preset bandwidth extension band as the starting point, the spectrum signals within the predetermined frequency band range or the predetermined frequency point range in the n copies of the audio frequency domain signal are sequentially used as the spectrum signals between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension band, where n is a positive integer or a positive fraction.

[0016] Optionally, in an embodiment of the present disclosure, the method of copying the n copies of the spectrum signals within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal includes:

[0017] Repeatingly copying the spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal in sequence to obtain n copies of the spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal; or

[0018] The spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal is mirror-copied multiple times to obtain n copies of the spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal.

[0019] Optionally, in an embodiment of the present disclosure, predicting a spectrum signal between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension band based on a spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal includes:

[0020] Taking the starting frequency point of the preset bandwidth extension band as the starting point, or taking the highest frequency point of the preset bandwidth extension band as the starting point, copying m copies of the spectrum signal within the predetermined frequency band range or the predetermined frequency point range in the audio frequency domain signal as the spectrum signal between the starting frequency point of the preset bandwidth extension band and the highest frequency point of the preset bandwidth extension band, where m is a positive integer or a positive fraction;

[0021] Taking the starting frequency point of the preset bandwidth extension band as the starting point, or taking the highest frequency point with bit allocation as the starting point, copy h copies of the spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal as the spectrum signal between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band, where h is a positive integer or a positive fraction.

[0022] Optionally, in an embodiment of the present disclosure, the method of copying the m or h copies of the spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal includes:

[0023] Repeatingly copying the spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal in sequence to obtain m or h copies of the spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal; or

[0024] The spectrum signal within the predetermined frequency band range or the predetermined frequency point range of the audio frequency domain signal is mirror-copied multiple times to obtain m or h copies of the spectrum signal within the predetermined frequency band range or the predetermined frequency point range of the audio frequency domain signal.

[0025] Optionally, in an embodiment of the present disclosure, the same method is used between different frames to predict the spectrum signal between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension band.

[0026] Optionally, in an embodiment of the present disclosure, the method further includes:

[0027] Frequency domain envelope correction is performed on the spectrum signal between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band.

[0028] Optionally, in an embodiment of the present disclosure, the performing frequency domain envelope correction on the spectrum signal between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band includes at least one of the following:

[0029] Based on the frequency domain envelope value of the spectrum signal between the first frequency point and the highest frequency point with bit allocation, the frequency domain envelope value of the spectrum signal between the highest frequency point with bit allocation and the intermediate frequency point between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band is corrected; and, based on the frequency domain envelope value of the spectrum signal between the starting frequency point of the preset bandwidth extension band and the second frequency point, the frequency domain envelope value of the spectrum signal between the intermediate frequency point and the starting frequency point of the preset bandwidth extension band is corrected; wherein, the first frequency point is: W1-0.5×Wx; W1 represents the highest frequency point with bit allocation, and Wx represents the frequency bandwidth between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band; the second frequency point is: W2+0.5×Wx; W2 represents the starting frequency point of the preset bandwidth extension band;

[0030] Based on the frequency domain envelope value of the spectrum signal between the third frequency point and the highest frequency point with bit allocation, the frequency domain envelope value of the spectrum signal between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band is corrected; wherein the third frequency point is: W1-Wx;

[0031] Based on the frequency domain envelope value of the spectrum signal between the starting frequency point and the fourth frequency point of the preset bandwidth extension band, the frequency domain envelope value of the spectrum signal between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band is corrected; wherein the fourth frequency point is: W2+Wx.

[0032] Optionally, in an embodiment of the present disclosure, the method further includes:

[0033] The bit stream is decoded to obtain at least one of the frequency domain envelope value of the spectrum signal between the first frequency point and the highest frequency point with bit allocation, the frequency domain envelope value of the spectrum signal between the starting frequency point of the preset bandwidth extension band and the second frequency point, the frequency domain envelope value of the spectrum signal between the third frequency point and the highest frequency point with bit allocation, and the frequency domain envelope value of the spectrum signal between the starting frequency point of the preset bandwidth extension band and the fourth frequency point.

[0034] Optionally, in an embodiment of the present disclosure, the method further includes:

[0035] Noise filling is performed on a frequency band between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension frequency band.

[0036] Optionally, in an embodiment of the present disclosure, the method further includes:

[0037] The audio frequency domain signal and the spectrum signal between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension band are added and combined, and then transformed from the frequency domain to the time domain to obtain a reconstructed audio time domain signal.

[0038] In a second aspect, an embodiment of the present disclosure provides a communication device, which is configured in a decoding device, including:

[0039] A transceiver module, used to receive a bit stream sent by an encoding device, and decode the bit stream to obtain a decoded audio frequency domain signal;

[0040] A processing module, configured to predict, in response to the highest frequency point with bit allocation of the audio frequency domain signal being lower than the starting frequency point of a preset bandwidth extension band, or the frequency band with bit allocation of the audio frequency domain signal being smaller than the preset bandwidth extension starting frequency band, a spectrum signal between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension band based on a spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal.

[0041] In a third aspect, an embodiment of the present disclosure provides a communication device, which includes a processor. When the processor calls a computer program in a memory, the method described in the first aspect is executed.

[0042] In a fourth aspect, an embodiment of the present disclosure provides a communication device, which includes a processor and a memory, in which a computer program is stored; the processor executes the computer program stored in the memory so that the communication device executes the method described in the first aspect above.

[0043] In a fifth aspect, an embodiment of the present disclosure provides a communication device, which includes a processor and an interface circuit, wherein the interface circuit is used to receive code instructions and transmit them to the processor, and the processor is used to run the code instructions to enable the device to execute the method described in the first aspect above.

[0044] In a sixth aspect, an embodiment of the present disclosure provides a communication system, the system includes the communication device described in the second aspect, or the system includes the communication device described in the third aspect, or the system includes the communication device described in the fourth aspect, or the system includes the communication device described in the fifth aspect.

[0045] In a sixth aspect, an embodiment of the present invention provides a computer-readable storage medium for storing instructions used by the above-mentioned network device, and when the instructions are executed, the terminal device executes the method described in the first aspect.

[0046] In a seventh aspect, the present disclosure further provides a computer program product comprising a computer program, which, when executed on a computer, enables the computer to execute the method described in the first aspect above.

[0047] In an eighth aspect, the present disclosure provides a chip system, which includes at least one processor and an interface, for supporting a network device to implement the functions involved in the method described in any aspect of the first aspect, for example, determining or processing at least one of the data and information involved in the above method. In one possible design, the chip system also includes a memory, which is used to store computer programs and data necessary for the source auxiliary node. The chip system can be composed of a chip, or it can include a chip and other discrete devices.

[0048] In a ninth aspect, the present disclosure provides a computer program, which, when executed on a computer, enables the computer to execute the method described in the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The above and / or additional aspects and advantages of the present disclosure will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0050] Figure 1a-1b A distribution relationship diagram between a bandwidth extension frequency band and a highest frequency point with bit allocation provided in an embodiment of the present disclosure;

[0051] Figure 1c A schematic diagram of the architecture of a communication system provided by an embodiment of the present disclosure;

[0052] Figure 2 A schematic diagram of a flow chart of a method for extending the frequency band of an audio signal provided by an embodiment of the present disclosure;

[0053] Figure 3a A flowchart of a method for extending the frequency band of an audio signal provided by an embodiment of the present disclosure;

[0054] Figure 3b A schematic diagram of a structure of a spectrum signal between a highest frequency point of bit allocation and a highest frequency point of a preset bandwidth extension band filled with spectrum signals within a predetermined frequency band range or a predetermined frequency point range in n audio frequency domain signals provided by an embodiment of the present disclosure;

[0055] Figure 3c A schematic diagram of a structure of a spectrum signal between a highest frequency point of bit allocation and a highest frequency point of a preset bandwidth extension band filled with spectrum signals within a predetermined frequency band range or a predetermined frequency point range in n audio frequency domain signals provided by an embodiment of the present disclosure;

[0056] Figure 4a A flowchart of a method for extending the frequency band of an audio signal provided by another embodiment of the present disclosure;

[0057] Figure 4b A schematic diagram of a structure of a spectrum signal between a highest frequency point of bit allocation and a highest frequency point of a preset bandwidth extension band filled with spectrum signals within a predetermined frequency band range or a predetermined frequency point range in m audio frequency domain signals provided by an embodiment of the present disclosure;

[0058] Figure 4c A schematic structural diagram of a spectrum signal between the highest frequency point of bit allocation and the highest frequency point of a preset bandwidth extension band provided by an embodiment of the present disclosure, based on a spectrum signal within a predetermined frequency band range or a predetermined frequency point range in h portions of an audio frequency domain signal;

[0059] Figure 5 A flowchart of a method for extending the frequency band of an audio signal provided by another embodiment of the present disclosure;

[0060] Figure 6 A flowchart of a method for extending the frequency band of an audio signal provided by another embodiment of the present disclosure;

[0061] Figure 7 A flowchart of a method for extending the frequency band of an audio signal provided by another embodiment of the present disclosure;

[0062] Figure 8 A schematic diagram of the structure of a communication device provided by an embodiment of the present disclosure;

[0063] Fig. 9 is a structural schematic diagram of a communication device provided by an embodiment of the present disclosure;

[0064] Fig.10 A schematic diagram of the structure of a chip provided by an embodiment of the present disclosure. DETAILED DESCRIPTION

[0065] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the embodiments of the present disclosure. Instead, they are merely examples of devices and methods consistent with some aspects of the embodiments of the present disclosure as detailed in the appended claims.

[0066] The terms used in the disclosed embodiments are only for the purpose of describing specific embodiments and are not intended to limit the disclosed embodiments. The singular forms of "a", "an" and "the" used in the disclosed embodiments and the appended claims are also intended to include plural forms unless the context clearly indicates other meanings. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0067] It should be understood that although the terms first, second, third, etc. may be used to describe various information in the disclosed embodiments, these information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the disclosed embodiments, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the words "if" and "if" as used herein may be interpreted as "at" or "when" or "in response to determination".

[0068] The embodiments of the present disclosure are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present disclosure, and cannot be understood as limiting the present disclosure.

[0069] To facilitate understanding, the terms involved in this application are first introduced.

[0070] 1. Frequency band

[0071] A frequency range or the width of a spectrum, a frequency point is a frequency point on the frequency band.

[0072] In order to better understand the method for extending the frequency band of an audio signal disclosed in the embodiment of the present disclosure, the communication system to which the embodiment of the present disclosure is applicable is first described below.

[0073] The embodiments of the present disclosure are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present disclosure, and cannot be understood as limiting the present disclosure.

[0074] See also Figure 1c , Figure 1c The following is a schematic diagram of the architecture of a communication system provided by an embodiment of the present disclosure. The communication system may include but is not limited to an encoding device and a decoding device, wherein the encoding device and the decoding device may be network devices or terminal devices. And, Figure 1c The number and form of the devices shown are for illustrative purposes only and do not constitute a limitation on the embodiments of the present disclosure. In actual applications, two or more encoding devices and two or more decoding devices may be included. Figure 1c The communication system shown in the figure includes an encoding device 11 and a decoding device 12, where the encoding device 11 is a network device and the decoding device 12 is a terminal device.

[0075] It should be noted that the technical solutions of the embodiments of the present disclosure can be applied to various communication systems, such as long term evolution (LTE) system, fifth generation (5G) mobile communication system, 5G new radio (NR) system, or other future new mobile communication systems.

[0076] The network device in the embodiment of the present disclosure is an entity on the network side for transmitting or receiving signals. For example, the network device 11 may be an evolved NodeB (eNB), a transmission reception point (TRP), a next generation NodeB (gNB) in an NR system, a base station in other future mobile communication systems, or an access node in a wireless fidelity (WiFi) system. The embodiment of the present disclosure does not limit the specific technology and specific device form adopted by the network device. The network device provided in the embodiment of the present disclosure may be composed of a central unit (CU) and a distributed unit (DU), wherein the CU may also be referred to as a control unit. The CU-DU structure may be used to split the protocol layer of the network device, such as a base station, and the functions of some protocol layers are placed in the CU for centralized control, and the functions of the remaining part or all of the protocol layers are distributed in the DU, and the DU is centrally controlled by the CU.

[0077] The terminal device in the embodiments of the present disclosure is an entity on the user side for receiving or transmitting signals, such as a mobile phone. The terminal device may also be referred to as a terminal device (terminal), user equipment (UE), mobile station (MS), mobile terminal device (MT), etc. The terminal device may be a car with communication function, a smart car, a mobile phone, a wearable device, a tablet computer (Pad), a computer with wireless transceiver function, a virtual reality (VR) terminal device, an augmented reality (AR) terminal device, a wireless terminal device in industrial control, a wireless terminal device in self-driving, a wireless terminal device in remote medical surgery, a wireless terminal device in smart grid, a wireless terminal device in transportation safety, a wireless terminal device in smart city, a wireless terminal device in smart home, etc. The embodiments of the present disclosure do not limit the specific technology and specific device form adopted by the terminal device.

[0078] Figure 2 A flowchart of a method for extending the frequency band of an audio signal provided by an embodiment of the present disclosure is applied to a decoding device, wherein: Figure 2 As shown, the audio signal frequency band extension method may include the following steps:

[0079] Step 201: Receive a bit stream sent by an encoding device, and decode the bit stream to obtain a decoded audio frequency domain signal.

[0080] Among them, in one embodiment of the present disclosure, the specific execution method of step 201 is similar to the prior art, and the present disclosure will not repeat it here.

[0081] And, referring to the background technology, it can be known that the audio frequency domain signal obtained by decoding in this step is specifically a low-frequency spectrum signal of the audio signal, that is, the above Figure 1a-1b The spectrum signal corresponds to the frequency band below the highest frequency point where bits are allocated.

[0082] It should be noted that the “spectrum signal” mentioned in the embodiments of the present disclosure may be a frequency band signal or a frequency point signal.

[0083] Step 202: In response to the highest frequency point of bit allocation in the audio frequency domain signal being lower than the starting frequency point of the preset bandwidth extension band, or the frequency band of bit allocation in the audio frequency domain signal being smaller than the preset bandwidth extension starting frequency band, a spectrum signal between the highest frequency point of bit allocation and the highest frequency point of the preset bandwidth extension band is predicted based on a spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal.

[0084] Among them, in one embodiment of the present disclosure, the starting frequency point and the highest frequency point of the preset bandwidth extension band can be predetermined by the decoding device based on the coding rate (i.e., the total number of bits) of the coding device and the frequency band range required for encoding the audio signal. Specifically, when the coding rate is higher, the starting frequency point of the bandwidth extension band can be set higher. For example, for ultra-wideband signals, when the coding rate is 24kbps, the starting frequency point of the bandwidth extension band preset by the frequency domain signal can be 6. 4kHz (kilohertz); when the coding rate is 32kbps, the starting frequency point of the bandwidth extension band preset by the frequency domain signal can be 8kHz. And, the highest frequency point of the bandwidth extension band refers to the highest point of the frequency band required to output the signal or a specified frequency point, wherein, for broadband signals, the highest frequency point of the preset bandwidth extension band can be 7kHz or 8kHz, and for ultra-wideband signals, the highest frequency point of the preset bandwidth extension band can be 14kHz or 16kHz or other preset specific frequencies.

[0085] And, in one embodiment of the present disclosure, the frequencies in the above-mentioned predetermined frequency band range or predetermined frequency range are all lower than the highest frequency with bit allocation. Figure 1a and Figure 1b As shown, the predetermined frequency band range is Figure 1a and Figure 1b In the black part, the frequencies in the predetermined frequency band are all lower than the highest frequency with bit allocation.

[0086] Further, in one embodiment of the present disclosure, the predetermined frequency band range or predetermined frequency point range can be determined based on the signal type and coding rate of the audio signal. Specifically, for example, at a lower coding rate, for harmonic signals, the frequency band range or frequency point range of the relatively better coded lower spectrum signal in the low spectrum signal can be selected as the predetermined frequency band range or predetermined frequency point range; for non-harmonic signals, the frequency band range or frequency point range of the relatively poorly coded higher spectrum signal in the low spectrum signal can be selected as the predetermined frequency band range or predetermined frequency point range; at a higher coding rate, for harmonic signals, a slightly higher frequency band or frequency point in the low spectrum signal can be selected as the predetermined frequency band range or predetermined frequency point range.

[0087] In addition, it can be known from the content of the above step 202 that the present disclosure specifically predicts the spectrum signal between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension band, rather than only predicting the spectrum signal of the bandwidth extension band, which will make the predicted spectrum signal correspond to the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band, and avoid the situation of "no spectrum signal exists between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band", thereby ensuring the balance of high and low frequency energy in the frame, and avoiding the mechanical feeling caused by spectrum holes, and improving the quality of reconstructed audio. Among them, the detailed description of "how the decoding device specifically predicts that the predicted spectrum signal corresponds to the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band" will be described in the subsequent embodiments.

[0088] In summary, in the audio signal band extension method provided by the present disclosure, the decoding device receives the bit stream sent by the encoding device, and decodes the bit stream to obtain the decoded audio frequency domain signal. In addition, in response to the highest frequency point of the bit allocation of the audio frequency domain signal being lower than the starting frequency point of the preset bandwidth extension band, or the frequency band of the bit allocation of the audio frequency domain signal being smaller than the preset bandwidth extension starting frequency band, the decoding device predicts the spectrum signal between the highest frequency point of the bit allocation and the highest frequency point of the preset bandwidth extension band based on the spectrum signal within the predetermined frequency band range or the predetermined frequency point range in the audio frequency domain signal. It can be seen from this that in the present disclosure, when the highest frequency point of the bit allocation of the audio frequency domain signal is lower than the starting frequency point of the preset bandwidth extension band, or when the frequency band of the bit allocation of the audio frequency domain signal is smaller than the preset bandwidth extension starting band, when predicting the spectrum signal in the present disclosure, what is specifically predicted is the spectrum signal between the highest frequency point of the bit allocation and the highest frequency point of the preset bandwidth extension band, rather than only predicting the spectrum signal of the bandwidth extension band. This will result in a predicted spectrum signal corresponding to the highest frequency point of the bit allocation and the starting frequency point of the preset bandwidth extension band, and avoid the situation where "there is no spectrum signal between the highest frequency point of the bit allocation and the starting frequency point of the preset bandwidth extension band", thereby ensuring the balance of high and low frequency energy within the frame, and avoiding the mechanical feel caused by spectrum holes, thereby improving the quality of reconstructed audio.

[0089] Figure 3a A flowchart of a method for extending the frequency band of an audio signal provided by an embodiment of the present disclosure is applied to a decoding device, wherein: Figure 3a As shown, the audio signal frequency band extension method may include the following steps:

[0090] Step 301, taking the highest frequency point with bit allocation as the starting point, or taking the highest frequency point of the preset bandwidth extension band as the starting point, the spectrum signals within the predetermined frequency band range or the predetermined frequency point range in the copied n audio frequency domain signals are sequentially used as the spectrum signals between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension band.

[0091] In one embodiment of the present disclosure, n is a positive integer or a positive fraction. n may be the ratio of the number of frequencies between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension band to the number of frequencies within the predetermined frequency band range or the predetermined frequency point range.

[0092] Furthermore, in one embodiment of the present disclosure, the copying method of the spectrum signals within the predetermined frequency band range or the predetermined frequency point range in the n audio frequency domain signals includes any one of the following:

[0093] The first method is to repeatedly copy the spectrum signal within a predetermined frequency band or a predetermined frequency point range in the audio frequency domain signal in sequence to obtain n spectrum signals within the predetermined frequency band or a predetermined frequency point range in the audio frequency domain signal.

[0094] That is, each of the spectrum signals within a predetermined frequency band range or a predetermined frequency point range in the n audio frequency domain signals is copied along the same direction (such as from high frequency to low frequency, or from low frequency to high frequency).

[0095] For example, Figure 3b A schematic diagram of a structure of a spectrum signal between the highest frequency point of bit allocation and the highest frequency point of a preset bandwidth extension band is provided in an embodiment of the present disclosure, based on a spectrum signal within a predetermined frequency band range or a predetermined frequency point range in n audio frequency domain signals, such as Figure 3b As shown, starting from the highest frequency point with bit allocation, the spectrum signals within the predetermined frequency band range or the predetermined frequency point range in the four audio frequency domain signals are copied in a sequentially repeated manner as the spectrum signals between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension band. The spectrum signals within the predetermined frequency band range or the predetermined frequency point range in each audio frequency domain signal are copied along the "direction from low frequency to high frequency".

[0096] The second method is to make multiple mirror copies (or folded copies) of the spectrum signal within a predetermined frequency band or a predetermined frequency point range in the audio frequency domain signal to obtain n copies of the spectrum signal within a predetermined frequency band or a predetermined frequency point range in the audio frequency domain signal.

[0097] That is, the copy directions of adjacent spectrum signals in the spectrum signals within the predetermined frequency band range or the predetermined frequency point range of the n audio frequency domain signals are different, such as: the copy direction of the i-th spectrum signal is from high frequency to low frequency, and the copy direction of the i+1-th spectrum signal is from low frequency to high frequency; or, the copy direction of the i-th spectrum signal is from low frequency to high frequency, and the copy direction of the i+1-th spectrum signal is from high frequency to low frequency. Wherein, i=1, 2, 3....n.

[0098] For example, Figure 3c A schematic diagram of a structure of a spectrum signal between the highest frequency point of bit allocation and the highest frequency point of a preset bandwidth extension band is provided in an embodiment of the present disclosure, based on a spectrum signal within a predetermined frequency band range or a predetermined frequency point range in n audio frequency domain signals, such as Figure 3c As shown, with the highest frequency point with bit allocation as the starting point, the spectrum signals within the predetermined frequency band range or the predetermined frequency point range in the audio frequency domain signal are copied in a mirror copy manner as the spectrum signals between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension band. Among them, when copying the first spectrum signal, it is copied along the direction of "low frequency to high frequency", when copying the second spectrum signal, it is copied along the direction of "high frequency to low frequency", when copying the third spectrum signal, it is copied along the direction of "low frequency to high frequency", and when copying the fourth spectrum signal, it is copied along the direction of "high frequency to low frequency".

[0099] It should be noted that in one embodiment of the present disclosure, the same method is specifically used between different frames to predict the spectrum signal between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension band. Figure 3a The method of the corresponding embodiment predicts the spectrum signal between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension band, thereby ensuring that the spectrum signal between frames is always consistent, ensuring the continuity of the audio signal between frames, and ensuring the reconstructed audio quality of the audio signal.

[0100] In summary, in the audio signal band extension method provided by the present disclosure, the decoding device receives the bit stream sent by the encoding device, and decodes the bit stream to obtain the decoded audio frequency domain signal. In addition, in response to the highest frequency point of the bit allocation of the audio frequency domain signal being lower than the starting frequency point of the preset bandwidth extension band, or the frequency band of the bit allocation of the audio frequency domain signal being smaller than the preset bandwidth extension starting frequency band, the decoding device predicts the spectrum signal between the highest frequency point of the bit allocation and the highest frequency point of the preset bandwidth extension band based on the spectrum signal within the predetermined frequency band range or the predetermined frequency point range in the audio frequency domain signal. It can be seen from this that in the present disclosure, when the highest frequency point of the bit allocation of the audio frequency domain signal is lower than the starting frequency point of the preset bandwidth extension band, or when the frequency band of the bit allocation of the audio frequency domain signal is smaller than the preset bandwidth extension starting band, when predicting the spectrum signal in the present disclosure, what is specifically predicted is the spectrum signal between the highest frequency point of the bit allocation and the highest frequency point of the preset bandwidth extension band, rather than only predicting the spectrum signal of the bandwidth extension band. This will result in a predicted spectrum signal corresponding to the highest frequency point of the bit allocation and the starting frequency point of the preset bandwidth extension band, and avoid the situation where "there is no spectrum signal between the highest frequency point of the bit allocation and the starting frequency point of the preset bandwidth extension band", thereby ensuring the balance of high and low frequency energy within the frame, and avoiding the mechanical feel caused by spectrum holes, thereby improving the quality of reconstructed audio.

[0101] Figure 4a A flowchart of a method for extending the frequency band of an audio signal provided by an embodiment of the present disclosure is applied to a decoding device, wherein: Figure 4a As shown, the audio signal frequency band extension method may include the following steps:

[0102] Step 401: Taking the starting frequency point of the preset bandwidth extension band as the starting point, or taking the highest frequency point of the preset bandwidth extension band as the starting point, copy m copies of the spectrum signal within the predetermined frequency band range or the predetermined frequency point range in the audio frequency domain signal as the spectrum signal between the starting frequency point of the preset bandwidth extension band and the highest frequency point of the preset bandwidth extension band.

[0103] In one embodiment of the present disclosure, m is a positive integer or a positive fraction. m can be the ratio of the number of frequencies between the starting frequency of the preset bandwidth extension band and the highest frequency of the preset bandwidth extension band to the number of frequencies within the preset frequency band range or the preset frequency range.

[0104] Furthermore, in one embodiment of the present disclosure, the copying method of the spectrum signals within the predetermined frequency band range or the predetermined frequency point range in the m audio frequency domain signals includes any one of the following:

[0105] The first method is to repeatedly copy the spectrum signal within a predetermined frequency band or a predetermined frequency point range in the audio frequency domain signal in sequence to obtain m copies of the spectrum signal within the predetermined frequency band or a predetermined frequency point range in the audio frequency domain signal.

[0106] The second method is to make multiple mirror copies (or folded copies) of the spectrum signal within a predetermined frequency band or a predetermined frequency point range in the audio frequency domain signal to obtain m copies of the spectrum signal within a predetermined frequency band or a predetermined frequency point range in the audio frequency domain signal.

[0107] Step 402: Taking the starting frequency point of the preset bandwidth extension band as the starting point, or taking the highest frequency point with bit allocation as the starting point, copy h copies of the spectrum signal within the predetermined frequency band range or the predetermined frequency point range in the audio frequency domain signal as the spectrum signal between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band.

[0108] In one embodiment of the present disclosure, h is a positive integer or a positive fraction. h can be the ratio of the number of frequencies between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band to the number of frequencies within the predetermined frequency band range or the predetermined frequency point range.

[0109] Furthermore, in one embodiment of the present disclosure, the copying method of the spectrum signal within the predetermined frequency band range or the predetermined frequency point range in the above-mentioned h parts of the audio frequency domain signal includes any one of the following:

[0110] The first method is to repeatedly copy the spectrum signal within a predetermined frequency band or a predetermined frequency point range in the audio frequency domain signal in sequence to obtain h copies of the spectrum signal within the predetermined frequency band or a predetermined frequency point range in the audio frequency domain signal.

[0111] The second method is to mirror copy (or fold copy) the spectrum signal within a predetermined frequency band or a predetermined frequency point range in the audio frequency domain signal multiple times to obtain h copies of the spectrum signal within a predetermined frequency band or a predetermined frequency point range in the audio frequency domain signal.

[0112] For detailed description of steps 401 to 402, please refer to the above embodiment description.

[0113] Furthermore, it should be noted that, in one embodiment of the present disclosure, the method of copying the spectrum signals within the predetermined frequency band range or the predetermined frequency point range in the above-mentioned m portions of audio frequency domain signals is consistent with the method of copying the spectrum signals within the predetermined frequency band range or the predetermined frequency point range in the above-mentioned h portions of audio frequency domain signals; that is, the above-mentioned first method (i.e., repeated copying in sequence) can be used to copy and obtain m portions of spectrum signals and h portions of spectrum signals, or the above-mentioned second method (i.e., multiple mirror copies) can be used to copy and obtain m portions of spectrum signals and h portions of spectrum signals.

[0114] Optionally, in one embodiment of the present disclosure, with respect to the use of a sequential copying method, if when filling the frequency band between the starting frequency point of a preset bandwidth extension band and the highest frequency point of the preset bandwidth extension band, and when filling the frequency band between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band, if the filling directions of the two are the same, such as when filling the frequency band between the starting frequency point of the preset bandwidth extension band and the highest frequency point of the preset bandwidth extension band, the filling starts from the starting frequency point of the preset bandwidth extension band, and, when filling the frequency band between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band, the filling starts from the highest frequency point with bit allocation, then the copying direction of the spectrum signal within the predetermined frequency band range or the predetermined frequency point range in the above-mentioned m portions of the audio frequency domain signal should be the same as the copying direction of the spectrum signal within the predetermined frequency band range or the predetermined frequency point range in the above-mentioned h portions of the audio frequency domain signal. For example, the copying direction of the spectrum signal within a predetermined frequency band range or a predetermined frequency point range in m audio frequency domain signals can be from high frequency to low frequency; the copying direction of the spectrum signal within a predetermined frequency band range or a predetermined frequency point range in h audio frequency domain signals can also be from high frequency to low frequency.

[0115] Optionally, in another embodiment of the present disclosure, with respect to the use of a sequential copying method, if when filling the frequency band between the starting frequency point of the preset bandwidth extension band and the highest frequency point of the preset bandwidth extension band, and when filling the frequency band between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band, the filling directions of the two are different, such as when filling the frequency band between the starting frequency point of the preset bandwidth extension band and the highest frequency point of the preset bandwidth extension band, the filling is started from the starting frequency point of the preset bandwidth extension band, and when filling the frequency band between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band, the filling is started from the starting frequency point of the preset bandwidth extension band, then the copying direction of the spectrum signal within the predetermined frequency band range or the predetermined frequency point range in the above-mentioned m portions of the audio frequency domain signal should be opposite to the copying direction of the spectrum signal within the predetermined frequency band range or the predetermined frequency point range in the above-mentioned h portions of the audio frequency domain signal. For example, the copying direction of the spectrum signal within a predetermined frequency band range or a predetermined frequency point range in m audio frequency domain signals can be from high frequency to low frequency; the copying direction of the spectrum signal within a predetermined frequency band range or a predetermined frequency point range in h audio frequency domain signals can be from low frequency to high frequency.

[0116] For example, Figure 4b A schematic diagram of a structure of a spectrum signal between the highest frequency point of bit allocation and the highest frequency point of a preset bandwidth extension band is provided in an embodiment of the present disclosure, based on a spectrum signal within a predetermined frequency band range or a predetermined frequency point range in m audio frequency domain signals, such as Figure 4bAs shown, for the frequency band from "the starting frequency point of the preset bandwidth extension band" to "the highest frequency point of the preset bandwidth extension band", taking the "starting frequency point of the preset bandwidth extension band" as the starting point, the spectrum signals within the predetermined frequency band range or the predetermined frequency point range in the copied two audio frequency domain signals are used as the spectrum signals between the starting frequency point of the preset bandwidth extension band and the highest frequency point of the preset bandwidth extension band in a manner of sequentially and repeatedly copying, wherein the copying direction of each spectrum signal is from low frequency to high frequency.

[0117] And, accordingly, Figure 4b As shown, for the frequency band from "the highest frequency point with bit allocation" to "the starting frequency point of the preset bandwidth extension band", taking the "starting frequency point of the preset bandwidth extension band" as the starting point, the spectrum signals within the predetermined frequency band range or the predetermined frequency point range in the two copied audio frequency domain signals are copied in a sequentially repeated manner as the spectrum signals between the starting frequency point of the preset bandwidth extension band and the highest frequency point of the preset bandwidth extension band, wherein the copy direction of each spectrum signal is from high frequency to low frequency.

[0118] As a further example, Figure 4c A schematic diagram of a structure of a spectrum signal between the highest frequency point of bit allocation and the highest frequency point of a preset bandwidth extension band is provided in an embodiment of the present disclosure, based on a spectrum signal within a predetermined frequency band range or a predetermined frequency point range in h portions of an audio frequency domain signal, such as Figure 4c As shown, for the frequency band from "the starting frequency point of the preset bandwidth extension band" to "the highest frequency point of the preset bandwidth extension band", taking the "starting frequency point of the preset bandwidth extension band" as the starting point, the spectrum signals within the predetermined frequency band range or the predetermined frequency point range in the copied two audio frequency domain signals are used as the spectrum signals between the starting frequency point of the preset bandwidth extension band and the highest frequency point of the preset bandwidth extension band in a mirror copying manner, wherein the copying direction of the first spectrum signal is from low frequency to high frequency, and the copying direction of the second spectrum signal is from high frequency to low frequency.

[0119] And, accordingly, Figure 4c As shown, for the frequency band from "the highest frequency point with bit allocation" to "the starting frequency point of the preset bandwidth extension band", with "the starting frequency point of the preset bandwidth extension band" as the starting point, the spectrum signals within the predetermined frequency band range or the predetermined frequency point range in the copied two audio frequency domain signals are used as the spectrum signals between the starting frequency point of the preset bandwidth extension band and the highest frequency point of the preset bandwidth extension band in a mirror copying manner, wherein the copying direction of the first spectrum signal is from low frequency to high frequency, and the copying direction of the second spectrum signal is from high frequency to low frequency.

[0120] It should be noted that in one embodiment of the present disclosure, the same method is specifically used between different frames to predict the spectrum signal between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension band. Figure 4a The method of the corresponding embodiment predicts the spectrum signal between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension band, thereby ensuring that the spectrum signal between frames is always consistent, ensuring the continuity of the audio signal between frames, and ensuring the reconstructed audio quality of the audio signal.

[0121] In summary, in the audio signal band extension method provided by the present disclosure, the decoding device receives the bit stream sent by the encoding device, and decodes the bit stream to obtain the decoded audio frequency domain signal. In addition, in response to the highest frequency point of the bit allocation of the audio frequency domain signal being lower than the starting frequency point of the preset bandwidth extension band, or the frequency band of the bit allocation of the audio frequency domain signal being smaller than the preset bandwidth extension starting frequency band, the decoding device predicts the spectrum signal between the highest frequency point of the bit allocation and the highest frequency point of the preset bandwidth extension band based on the spectrum signal within the predetermined frequency band range or the predetermined frequency point range in the audio frequency domain signal. It can be seen from this that in the present disclosure, when the highest frequency point of the bit allocation of the audio frequency domain signal is lower than the starting frequency point of the preset bandwidth extension band, or when the frequency band of the bit allocation of the audio frequency domain signal is smaller than the preset bandwidth extension starting band, when predicting the spectrum signal in the present disclosure, what is specifically predicted is the spectrum signal between the highest frequency point of the bit allocation and the highest frequency point of the preset bandwidth extension band, rather than only predicting the spectrum signal of the bandwidth extension band. This will result in a predicted spectrum signal corresponding to the highest frequency point of the bit allocation and the starting frequency point of the preset bandwidth extension band, and avoid the situation where "there is no spectrum signal between the highest frequency point of the bit allocation and the starting frequency point of the preset bandwidth extension band", thereby ensuring the balance of high and low frequency energy within the frame, and avoiding the mechanical feel caused by spectrum holes, thereby improving the quality of reconstructed audio.

[0122] Figure 5 A flowchart of a method for extending the frequency band of an audio signal provided by an embodiment of the present disclosure is applied to a decoding device, wherein: Figure 5 As shown, the audio signal frequency band extension method may include the following steps:

[0123] Step 501: Perform frequency domain envelope correction on a spectrum signal between the highest frequency point with bit allocation and the starting frequency point of a preset bandwidth extension band.

[0124] Among them, in one embodiment of the present disclosure, the method for performing frequency domain envelope correction on the spectrum signal between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band may include any of the following:

[0125] The first is to correct the frequency domain envelope value of the spectrum signal between the highest frequency point with bit allocation and the intermediate frequency point between the highest frequency point with bit allocation and the starting frequency point of a preset bandwidth extension band based on the frequency domain envelope value of the spectrum signal between the first frequency point and the highest frequency point with bit allocation; and, to correct the frequency domain envelope value of the spectrum signal between the intermediate frequency point and the starting frequency point of the preset bandwidth extension band based on the frequency domain envelope value of the spectrum signal between the starting frequency point of the preset bandwidth extension band and the second frequency point.

[0126] Specifically, in one embodiment of the present disclosure, the first frequency point is: W1-0.5×Wx; W1 represents the highest frequency point with bit allocation, and Wx represents the bandwidth between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band; the second frequency point is: W2+0.5×Wx; W2 represents the starting frequency point of the preset bandwidth extension band.

[0127] And, in one embodiment of the present disclosure, the above-mentioned "correcting the frequency domain envelope value of the spectrum signal between the highest frequency point with bit allocation and the intermediate frequency point between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band based on the frequency domain envelope value of the spectrum signal between the first frequency point and the highest frequency point with bit allocation" can specifically include: making the frequency domain envelope value of the spectrum signal between the highest frequency point with bit allocation and the intermediate frequency point equal to the frequency domain envelope value of the spectrum signal between the first frequency point and the highest frequency point with bit allocation; or, making the changing trend of the frequency domain envelope value of the spectrum signal between the highest frequency point with bit allocation and the intermediate frequency point equal to the changing trend of the frequency domain envelope value of the spectrum signal between the first frequency point and the highest frequency point with bit allocation.

[0128] Furthermore, the above-mentioned "correcting the frequency domain envelope value of the spectrum signal between the intermediate frequency point and the starting frequency point of the preset bandwidth extension band based on the frequency domain envelope value of the spectrum signal between the starting frequency point and the second frequency point of the preset bandwidth extension band" may include: making the frequency domain envelope value of the spectrum signal between the highest frequency point and the intermediate frequency point with bit allocation equal to the frequency domain envelope value of the spectrum signal between the starting frequency point and the second frequency point of the preset bandwidth extension band; or making the changing trend of the frequency domain envelope value of the spectrum signal between the highest frequency point and the intermediate frequency point with bit allocation equal to the changing trend of the frequency domain envelope value of the spectrum signal between the starting frequency point and the second frequency point of the preset bandwidth extension band.

[0129] The second method is to correct the frequency domain envelope value of the spectrum signal between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band based on the frequency domain envelope value of the spectrum signal between the third frequency point and the highest frequency point with bit allocation.

[0130] Among them, the third frequency point can be: W1-Wx.

[0131] Furthermore, the above-mentioned correction of the frequency domain envelope value of the spectrum signal between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band based on the frequency domain envelope value of the spectrum signal between the third frequency point and the highest frequency point with bit allocation can specifically include: making the frequency domain envelope value of the spectrum signal between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band equal to the frequency domain envelope value of the spectrum signal between the third frequency point and the highest frequency point with bit allocation; or making the changing trend of the frequency domain envelope value of the spectrum signal between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band equal to the changing trend of the frequency domain envelope value of the spectrum signal between the third frequency point and the highest frequency point with bit allocation.

[0132] In addition, the frequency domain envelope value of the frequency band or frequency point near the starting frequency point of the preset bandwidth extension band can be corrected based on the frequency domain envelope value of the starting frequency point of the preset bandwidth extension band, so as to ensure that the frequency domain envelope value of the frequency band or frequency point smaller than the starting frequency point of the preset bandwidth extension band remains continuous with the frequency domain envelope value of the starting frequency point of the preset bandwidth extension band.

[0133] The third type is to correct the frequency domain envelope value of the spectrum signal between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band based on the frequency domain envelope value of the spectrum signal between the starting frequency point and the fourth frequency point of the preset bandwidth extension band.

[0134] Among them, the fourth frequency point is: W2+Wx.

[0135] Furthermore, the above-mentioned correction of the frequency domain envelope value of the spectrum signal between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band based on the frequency domain envelope value of the spectrum signal between the starting frequency point of the preset bandwidth extension band to the fourth frequency point may specifically include: making the frequency domain envelope value of the spectrum signal between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band equal to the frequency domain envelope value of the spectrum signal between the starting frequency point of the preset bandwidth extension band to the fourth frequency point; or making the changing trend of the frequency domain envelope value of the spectrum signal between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band equal to the changing trend of the frequency domain envelope value of the spectrum signal between the starting frequency point of the preset bandwidth extension band to the fourth frequency point.

[0136] In addition, the frequency domain envelope value of the frequency band or frequency point near the highest frequency point with bit allocation can be corrected based on the frequency domain envelope value of the highest frequency point with bit allocation, so as to ensure that the frequency domain envelope value of the frequency band or frequency point greater than the highest frequency point with bit allocation remains continuous with the frequency domain envelope value of the highest frequency point with bit allocation.

[0137] Among them, it should be noted that the frequency domain envelope value of the spectrum signal between the first frequency point and the highest frequency point with bit allocation, the frequency domain envelope value of the spectrum signal between the starting frequency point of the preset bandwidth extension band and the second frequency point, the frequency domain envelope value of the spectrum signal between the third frequency point and the highest frequency point with bit allocation, and the frequency domain envelope value of the spectrum signal between the starting frequency point of the preset bandwidth extension band and the fourth frequency point can all be obtained by the decoding device by decoding the bit stream it receives.

[0138] It can be seen from the above content that in the present disclosure, after filling the spectrum signal between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension band, the spectrum signal between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band will also be subjected to frequency domain envelope correction, so as to ensure the continuity of the frequency domain envelope value between the spectrum signal between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band, and also ensure the continuity of the frequency domain envelope value of the frequency band or frequency point less than the starting frequency point of the preset bandwidth extension band and the frequency domain envelope value of the starting frequency point of the preset bandwidth extension band, and ensure the continuity of the frequency domain envelope value of the frequency band or frequency point greater than the highest frequency point with bit allocation and the frequency domain envelope value of the highest frequency point with bit allocation, thereby ensuring the continuity of the subsequently reconstructed audio signal, solving the mechanical sense problem caused by spectrum holes, and ensuring the reconstructed audio quality of the audio signal.

[0139] In summary, in the audio signal band extension method provided by the present disclosure, the decoding device receives the bit stream sent by the encoding device, and decodes the bit stream to obtain the decoded audio frequency domain signal. In addition, in response to the highest frequency point of the bit allocation of the audio frequency domain signal being lower than the starting frequency point of the preset bandwidth extension band, or the frequency band of the bit allocation of the audio frequency domain signal being smaller than the preset bandwidth extension starting frequency band, the decoding device predicts the spectrum signal between the highest frequency point of the bit allocation and the highest frequency point of the preset bandwidth extension band based on the spectrum signal within the predetermined frequency band range or the predetermined frequency point range in the audio frequency domain signal. It can be seen from this that in the present disclosure, when the highest frequency point of the bit allocation of the audio frequency domain signal is lower than the starting frequency point of the preset bandwidth extension band, or when the frequency band of the bit allocation of the audio frequency domain signal is smaller than the preset bandwidth extension starting band, when predicting the spectrum signal in the present disclosure, what is specifically predicted is the spectrum signal between the highest frequency point of the bit allocation and the highest frequency point of the preset bandwidth extension band, rather than only predicting the spectrum signal of the bandwidth extension band. This will result in a predicted spectrum signal corresponding to the highest frequency point of the bit allocation and the starting frequency point of the preset bandwidth extension band, and avoid the situation where "there is no spectrum signal between the highest frequency point of the bit allocation and the starting frequency point of the preset bandwidth extension band", thereby ensuring the balance of high and low frequency energy within the frame, and avoiding the mechanical feel caused by spectrum holes, thereby improving the quality of reconstructed audio.

[0140] Figure 6 A flowchart of a method for extending the frequency band of an audio signal provided by an embodiment of the present disclosure is applied to a decoding device, wherein: Figure 6 As shown, the audio signal frequency band extension method may include the following steps:

[0141] Step 601: Noise filling is performed on a frequency band between the highest frequency point with bit allocation and the highest frequency point of a preset bandwidth extension band.

[0142] In summary, in the audio signal band extension method provided by the present disclosure, the decoding device receives the bit stream sent by the encoding device, and decodes the bit stream to obtain the decoded audio frequency domain signal. In addition, in response to the highest frequency point of the bit allocation of the audio frequency domain signal being lower than the starting frequency point of the preset bandwidth extension band, or the frequency band of the bit allocation of the audio frequency domain signal being smaller than the preset bandwidth extension starting frequency band, the decoding device predicts the spectrum signal between the highest frequency point of the bit allocation and the highest frequency point of the preset bandwidth extension band based on the spectrum signal within the predetermined frequency band range or the predetermined frequency point range in the audio frequency domain signal. It can be seen from this that in the present disclosure, when the highest frequency point of the bit allocation of the audio frequency domain signal is lower than the starting frequency point of the preset bandwidth extension band, or when the frequency band of the bit allocation of the audio frequency domain signal is smaller than the preset bandwidth extension starting band, when predicting the spectrum signal in the present disclosure, what is specifically predicted is the spectrum signal between the highest frequency point of the bit allocation and the highest frequency point of the preset bandwidth extension band, rather than only predicting the spectrum signal of the bandwidth extension band. This will result in a predicted spectrum signal corresponding to the highest frequency point of the bit allocation and the starting frequency point of the preset bandwidth extension band, and avoid the situation where "there is no spectrum signal between the highest frequency point of the bit allocation and the starting frequency point of the preset bandwidth extension band", thereby ensuring the balance of high and low frequency energy within the frame, and avoiding the mechanical feel caused by spectrum holes, thereby improving the quality of reconstructed audio.

[0143] Figure 7 A flowchart of a method for extending the frequency band of an audio signal provided by an embodiment of the present disclosure is applied to a decoding device, wherein: Figure 7 As shown, the audio signal frequency band extension method may include the following steps:

[0144] Step 701: Add and combine the audio frequency domain signal and the spectrum signal between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension band, and then transform from the frequency domain to the time domain to obtain a reconstructed audio time domain signal.

[0145] In summary, in the audio signal band extension method provided by the present disclosure, the decoding device receives the bit stream sent by the encoding device, and decodes the bit stream to obtain the decoded audio frequency domain signal. In addition, in response to the highest frequency point of the bit allocation of the audio frequency domain signal being lower than the starting frequency point of the preset bandwidth extension band, or the frequency band of the bit allocation of the audio frequency domain signal being smaller than the preset bandwidth extension starting frequency band, the decoding device predicts the spectrum signal between the highest frequency point of the bit allocation and the highest frequency point of the preset bandwidth extension band based on the spectrum signal within the predetermined frequency band range or the predetermined frequency point range in the audio frequency domain signal. It can be seen from this that in the present disclosure, when the highest frequency point of the bit allocation of the audio frequency domain signal is lower than the starting frequency point of the preset bandwidth extension band, or when the frequency band of the bit allocation of the audio frequency domain signal is smaller than the preset bandwidth extension starting band, when predicting the spectrum signal in the present disclosure, what is specifically predicted is the spectrum signal between the highest frequency point of the bit allocation and the highest frequency point of the preset bandwidth extension band, rather than only predicting the spectrum signal of the bandwidth extension band. This will result in a predicted spectrum signal corresponding to the highest frequency point of the bit allocation and the starting frequency point of the preset bandwidth extension band, and avoid the situation where "there is no spectrum signal between the highest frequency point of the bit allocation and the starting frequency point of the preset bandwidth extension band", thereby ensuring the balance of high and low frequency energy within the frame, and avoiding the mechanical feel caused by spectrum holes, thereby improving the quality of reconstructed audio.

[0146] Figure 8 A schematic diagram of the structure of a communication device provided by an embodiment of the present disclosure is shown in FIG. Figure 8 As shown, the apparatus may include:

[0147] A transceiver module, used to receive a bit stream sent by an encoding device, and decode the bit stream to obtain a decoded audio frequency domain signal;

[0148] A processing module, configured to predict, in response to the highest frequency point with bit allocation of the audio frequency domain signal being lower than the starting frequency point of a preset bandwidth extension band, or the frequency band with bit allocation of the audio frequency domain signal being smaller than the preset bandwidth extension starting frequency band, a spectrum signal between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension band based on a spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal.

[0149] In summary, in the communication device provided in the embodiment of the present disclosure, the decoding device receives the bit stream sent by the encoding device, and decodes the bit stream to obtain the decoded audio frequency domain signal. In addition, in response to the highest frequency point of the bit allocation of the audio frequency domain signal being lower than the starting frequency point of the preset bandwidth extension band, or the frequency band of the bit allocation of the audio frequency domain signal being smaller than the preset bandwidth extension starting frequency band, the decoding device predicts the spectrum signal between the highest frequency point of the bit allocation and the highest frequency point of the preset bandwidth extension band based on the spectrum signal within the predetermined frequency band range or the predetermined frequency point range in the audio frequency domain signal. It can be seen from this that in the present disclosure, when the highest frequency point of the bit allocation of the audio frequency domain signal is lower than the starting frequency point of the preset bandwidth extension band, or when the frequency band of the bit allocation of the audio frequency domain signal is smaller than the preset bandwidth extension starting band, when predicting the spectrum signal in the present disclosure, what is specifically predicted is the spectrum signal between the highest frequency point of the bit allocation and the highest frequency point of the preset bandwidth extension band, rather than only predicting the spectrum signal of the bandwidth extension band. This will result in a predicted spectrum signal corresponding to the highest frequency point of the bit allocation and the starting frequency point of the preset bandwidth extension band, and avoid the situation where "there is no spectrum signal between the highest frequency point of the bit allocation and the starting frequency point of the preset bandwidth extension band", thereby ensuring the balance of high and low frequency energy within the frame, and avoiding the mechanical feel caused by spectrum holes, thereby improving the quality of reconstructed audio.

[0150] Optionally, in one embodiment of the present disclosure, the device is further used for:

[0151] The starting frequency point and the highest frequency point of the preset bandwidth extension band are determined based on the encoding rate of the encoding device and the frequency band range required for encoding the audio signal.

[0152] Optionally, in an embodiment of the present disclosure, the frequencies in the predetermined frequency band range or the predetermined frequency point range are all lower than the highest frequency point with bit allocation.

[0153] Optionally, in an embodiment of the present disclosure, the processing module is further configured to:

[0154] Taking the highest frequency point with bit allocation as the starting point, or taking the highest frequency point of the preset bandwidth extension band as the starting point, the spectrum signals within the predetermined frequency band range or the predetermined frequency point range in the n copies of the audio frequency domain signal are sequentially used as the spectrum signals between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension band, where n is a positive integer or a positive fraction.

[0155] Optionally, in an embodiment of the present disclosure, the method of copying the n copies of the spectrum signals within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal includes:

[0156] Repeatingly copying the spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal in sequence to obtain n copies of the spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal; or

[0157] The spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal is mirror-copied multiple times to obtain n copies of the spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal.

[0158] Optionally, in an embodiment of the present disclosure, the processing module is further configured to:

[0159] Taking the starting frequency point of the preset bandwidth extension band as the starting point, or taking the highest frequency point of the preset bandwidth extension band as the starting point, copying m copies of the spectrum signal within the predetermined frequency band range or the predetermined frequency point range in the audio frequency domain signal as the spectrum signal between the starting frequency point of the preset bandwidth extension band and the highest frequency point of the preset bandwidth extension band, where m is a positive integer or a positive fraction;

[0160] Taking the starting frequency point of the preset bandwidth extension band as the starting point, or taking the highest frequency point with bit allocation as the starting point, copy h copies of the spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal as the spectrum signal between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band, where h is a positive integer or a positive fraction.

[0161] Optionally, in an embodiment of the present disclosure, the method of copying the m or h copies of the spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal includes:

[0162] Repeatingly copying the spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal in sequence to obtain m or h copies of the spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal; or

[0163] The spectrum signal within the predetermined frequency band range or the predetermined frequency point range of the audio frequency domain signal is mirror-copied multiple times to obtain m or h copies of the spectrum signal within the predetermined frequency band range or the predetermined frequency point range of the audio frequency domain signal.

[0164] Optionally, in an embodiment of the present disclosure, the same method is used between different frames to predict the spectrum signal between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension band.

[0165] Optionally, in one embodiment of the present disclosure, the device is further used for:

[0166] Frequency domain envelope correction is performed on the spectrum signal between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band.

[0167] Optionally, in an embodiment of the present disclosure, the device is also used for any of the following:

[0168] Based on the frequency domain envelope value of the spectrum signal between the first frequency point and the highest frequency point with bit allocation, the frequency domain envelope value of the spectrum signal between the highest frequency point with bit allocation and the intermediate frequency point between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band is corrected; and, based on the frequency domain envelope value of the spectrum signal between the starting frequency point of the preset bandwidth extension band and the second frequency point, the frequency domain envelope value of the spectrum signal between the intermediate frequency point and the starting frequency point of the preset bandwidth extension band is corrected; wherein, the first frequency point is: W1-0.5×Wx; W1 represents the highest frequency point with bit allocation, and Wx represents the frequency bandwidth between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band; the second frequency point is: W2+0.5×Wx; W2 represents the starting frequency point of the preset bandwidth extension band;

[0169] Based on the frequency domain envelope value of the spectrum signal between the third frequency point and the highest frequency point with bit allocation, the frequency domain envelope value of the spectrum signal between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band is corrected; wherein the third frequency point is: W1-Wx;

[0170] Based on the frequency domain envelope value of the spectrum signal between the starting frequency point and the fourth frequency point of the preset bandwidth extension band, the frequency domain envelope value of the spectrum signal between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band is corrected; wherein the fourth frequency point is: W2+Wx.

[0171] Optionally, in one embodiment of the present disclosure, the device is further used for:

[0172] The bit stream is decoded to obtain at least one of the frequency domain envelope value of the spectrum signal between the first frequency point and the highest frequency point with bit allocation, the frequency domain envelope value of the spectrum signal between the starting frequency point of the preset bandwidth extension band and the second frequency point, the frequency domain envelope value of the spectrum signal between the third frequency point and the highest frequency point with bit allocation, and the frequency domain envelope value of the spectrum signal between the starting frequency point of the preset bandwidth extension band and the fourth frequency point.

[0173] Optionally, in one embodiment of the present disclosure, the device is used to:

[0174] Noise filling is performed on a frequency band between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension frequency band.

[0175] Optionally, in one embodiment of the present disclosure, the device is further used for:

[0176] The audio frequency domain signal and the spectrum signal between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension band are added and combined, and then transformed from the frequency domain to the time domain to obtain a reconstructed audio time domain signal.

[0177] See also Fig. 9 , Fig. 9 1 is a schematic diagram of the structure of a communication device 900 provided in an embodiment of the present application. The communication device 900 may be a network device, or a terminal device, or a chip, a chip system, or a processor that supports the network device to implement the above method, or a chip, a chip system, or a processor that supports the terminal device to implement the above method. The device may be used to implement the method described in the above method embodiment, and the details may refer to the description in the above method embodiment.

[0178] The communication device 900 may include one or more processors 901. The processor 901 may be a general-purpose processor or a dedicated processor, etc. For example, it may be a baseband processor or a central processing unit. The baseband processor may be used to process the communication protocol and communication data, and the central processing unit may be used to control the communication device (such as a base station, a baseband chip, a terminal device, a terminal device chip, a DU or a CU, etc.), execute a computer program, and process the data of the computer program.

[0179] Optionally, the communication device 900 may further include one or more memories 902, on which a computer program 904 may be stored, and the processor 901 executes the computer program 904 so that the communication device 900 performs the method described in the above method embodiment. Optionally, data may also be stored in the memory 902. The communication device 900 and the memory 902 may be provided separately or integrated together.

[0180] Optionally, the communication device 900 may further include a transceiver 905 and an antenna 906. The transceiver 905 may be referred to as a transceiver unit, a transceiver, or a transceiver circuit, etc., and is used to implement a transceiver function. The transceiver 905 may include a receiver and a transmitter, the receiver may be referred to as a receiver or a receiving circuit, etc., and is used to implement a receiving function; the transmitter may be referred to as a transmitter or a transmitting circuit, etc., and is used to implement a transmitting function.

[0181] Optionally, the communication device 900 may further include one or more interface circuits 907. The interface circuit 907 is used to receive code instructions and transmit them to the processor 901. The processor 901 runs the code instructions to enable the communication device 900 to perform the method described in the above method embodiment.

[0182] In one implementation, the processor 901 may include a transceiver for implementing receiving and sending functions. For example, the transceiver may be a transceiver circuit, an interface, or an interface circuit. The transceiver circuit, interface, or interface circuit for implementing the receiving and sending functions may be separate or integrated. The above-mentioned transceiver circuit, interface, or interface circuit may be used for reading and writing code / data, or the above-mentioned transceiver circuit, interface, or interface circuit may be used for transmitting or delivering signals.

[0183] In one implementation, the processor 901 may store a computer program 903, which runs on the processor 901 and enables the communication device 900 to perform the method described in the above method embodiment. The computer program 903 may be fixed in the processor 901, in which case the processor 901 may be implemented by hardware.

[0184] In one implementation, the communication device 900 may include a circuit that can implement the functions of sending, receiving or communicating in the aforementioned method embodiment. The processor and transceiver described in the present application can be implemented in an integrated circuit (IC), an analog IC, a radio frequency integrated circuit RFIC, a mixed signal IC, an application specific integrated circuit (ASIC), a printed circuit board (PCB), an electronic device, etc. The processor and transceiver can also be manufactured using various IC process technologies, such as complementary metal oxide semiconductor (CMOS), N-type metal oxide semiconductor (nMetal-oxide-semiconductor, NMOS), P-type metal oxide semiconductor (positive channelmetal oxide semiconductor, PMOS), bipolar junction transistor (bipolar junction transistor, BJT), bipolar CMOS (BiCMOS), silicon germanium (SiGe), gallium arsenide (GaAs), etc.

[0185] The communication device described in the above embodiments may be a network device or a terminal device, but the scope of the communication device described in the present application is not limited thereto, and the structure of the communication device may not be limited thereto. Fig. 9 The communication device may be an independent device or may be part of a larger device. For example, the communication device may be:

[0186] (1) Independent integrated circuit IC, or chip, or chip system or subsystem;

[0187] (2) A collection of one or more ICs, optionally including a storage component for storing data or computer programs;

[0188] (3) ASIC, such as modem;

[0189] (4) Modules that can be embedded in other devices;

[0190] (5) Receivers, terminal devices, intelligent terminal devices, cellular phones, wireless devices, handheld devices, mobile units, vehicle-mounted devices, network devices, cloud devices, artificial intelligence devices, etc.;

[0191] (6) Others

[0192] For the case where the communication device may be a chip or a chip system, see Fig.10 Schematic diagram of the chip structure shown. Fig.10 The chip shown includes a processor 1001 and an interface 1002. The number of the processor 1001 may be one or more, and the number of the interface 1002 may be multiple.

[0193] Optionally, the chip further includes a memory 1003, and the memory 1003 is used to store necessary computer programs and data.

[0194] Those skilled in the art may also understand that the various illustrative logical blocks and steps listed in the embodiments of the present application may be implemented by electronic hardware, computer software, or a combination of the two. Whether such functions are implemented by hardware or software depends on the specific application and the design requirements of the entire system. Those skilled in the art may use various methods to implement the functions described for each specific application, but such implementation should not be understood as exceeding the scope of protection of the embodiments of the present application.

[0195] The present application also provides a readable storage medium having instructions stored thereon, which implement the functions of any of the above method embodiments when executed by a computer.

[0196] The present application also provides a computer program product, which implements the functions of any of the above method embodiments when executed by a computer.

[0197] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer programs. When the computer program is loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer program may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer program may be transmitted from a website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The computer-readable storage medium may be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrated. The available medium may be a magnetic medium (eg, a floppy disk, a hard disk, a magnetic tape), an optical medium (eg, a digital video disc (DVD)), or a semiconductor medium (eg, a solid state disk (SSD)).

[0198] A person skilled in the art may understand that the various numerical numbers such as first and second involved in the present application are only used for the convenience of description and are not used to limit the scope of the embodiments of the present application, and also indicate the order of precedence.

[0199] At least one in the present application can also be described as one or more, and a plurality can be two, three, four or more, which is not limited in the present application. In the embodiments of the present application, for a technical feature, the technical features in the technical feature are distinguished by "first", "second", "third", "A", "B", "C" and "D", etc., and there is no order of precedence or size between the technical features described by the "first", "second", "third", "A", "B", "C" and "D".

[0200] The corresponding relationships shown in each table in the present application can be configured or predefined. The values ​​of the information in each table are only examples and can be configured as other values, which are not limited by the present application. When configuring the corresponding relationship between the information and each parameter, it is not necessarily required to configure all the corresponding relationships illustrated in each table. For example, in the table in the present application, the corresponding relationships shown in some rows may not be configured. For another example, appropriate deformation adjustments can be made based on the above table, such as splitting, merging, etc. The names of the parameters shown in the titles of the above tables can also use other names that can be understood by the communication device, and the values ​​or representations of the parameters can also be other values ​​or representations that can be understood by the communication device. When implementing the above tables, other data structures can also be used, such as arrays, queues, containers, stacks, linear lists, pointers, linked lists, trees, graphs, structures, classes, heaps, hash tables or hash tables.

[0201] The predefined in the present application may be understood as defined, predefined, stored, pre-stored, pre-negotiated, pre-configured, solidified, or pre-burned.

[0202] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0203] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0204] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A method for extending the frequency band of an audio signal, characterized in that: Executed by the decoding device, including: Receiving a bit stream sent by an encoding device, and decoding the bit stream to obtain a decoded audio frequency domain signal; In response to the highest frequency point of bit allocation in the audio frequency domain signal being lower than the starting frequency point of a preset bandwidth extension band, or the frequency band position of bit allocation in the audio frequency domain signal being lower than the starting position of a preset bandwidth extension band, a spectrum signal between the highest frequency point of bit allocation and the highest frequency point of the preset bandwidth extension band is predicted based on a spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal.

2. The method according to claim 1, characterized in that The method further comprises: The starting frequency point and the highest frequency point of the preset bandwidth extension band are determined based on the encoding rate of the encoding device and the frequency band range required for encoding the audio signal.

3. The method according to claim 1, characterized in that The frequencies in the predetermined frequency band range or the predetermined frequency point range are all lower than the highest frequency point with bit allocation.

4. The method according to claim 1, characterized in that The predicting of the spectrum signal between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension band based on the spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal comprises: Taking the highest frequency point with bit allocation as the starting point, or taking the highest frequency point of the preset bandwidth extension band as the starting point, the spectrum signals within the predetermined frequency band range or the predetermined frequency point range in the n copies of the audio frequency domain signal are sequentially used as the spectrum signals between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension band, where n is a positive integer or a positive fraction.

5. The method according to claim 4, characterized in that The method of copying the n copies of the spectrum signals within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal includes: Repeatingly copying the spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal in sequence to obtain n copies of the spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal; or The spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal is mirror-copied multiple times to obtain n copies of the spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal.

6. The method according to claim 1, characterized in that The predicting of the spectrum signal between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension band based on the spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal comprises: Taking the starting frequency point of the preset bandwidth extension band as the starting point, or taking the highest frequency point of the preset bandwidth extension band as the starting point, copying m copies of the spectrum signal within the predetermined frequency band range or the predetermined frequency point range in the audio frequency domain signal as the spectrum signal between the starting frequency point of the preset bandwidth extension band and the highest frequency point of the preset bandwidth extension band, where m is a positive integer or a positive fraction; Taking the starting frequency point of the preset bandwidth extension band as the starting point, or taking the highest frequency point with bit allocation as the starting point, copy h copies of the spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal as the spectrum signal between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band, where h is a positive integer or a positive fraction.

7. The method according to claim 6, characterized in that The method of copying the m or h copies of the spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal includes: Repeatingly copying the spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal in sequence to obtain m or h copies of the spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal; or The spectrum signal within the predetermined frequency band range or the predetermined frequency point range of the audio frequency domain signal is mirror-copied multiple times to obtain m or h copies of the spectrum signal within the predetermined frequency band range or the predetermined frequency point range of the audio frequency domain signal.

8. The method according to any one of claims 1 to 7, characterized in that: The same method is adopted between different frames to predict the spectrum signal between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension band.

9. The method according to claim 1, characterized in that The method further comprises: Frequency domain envelope correction is performed on the spectrum signal between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band.

10. The method according to claim 9, characterized in that The performing frequency domain envelope correction on the spectrum signal between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band includes at least one of the following: Based on the frequency domain envelope value of the spectrum signal between the first frequency point and the highest frequency point with bit allocation, the frequency domain envelope value of the spectrum signal between the highest frequency point with bit allocation and the intermediate frequency point between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band is corrected; and, based on the frequency domain envelope value of the spectrum signal between the starting frequency point of the preset bandwidth extension band and the second frequency point, the frequency domain envelope value of the spectrum signal between the intermediate frequency point and the starting frequency point of the preset bandwidth extension band is corrected; wherein, the first frequency point is: W1-0.5×Wx; W1 represents the highest frequency point with bit allocation, and Wx represents the frequency bandwidth between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band; the second frequency point is: W2+0.5×Wx; W2 represents the starting frequency point of the preset bandwidth extension band; Based on the frequency domain envelope value of the spectrum signal between the third frequency point and the highest frequency point with bit allocation, the frequency domain envelope value of the spectrum signal between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band is corrected; wherein the third frequency point is: W1-Wx; Based on the frequency domain envelope value of the spectrum signal between the starting frequency point and the fourth frequency point of the preset bandwidth extension band, the frequency domain envelope value of the spectrum signal between the highest frequency point with bit allocation and the starting frequency point of the preset bandwidth extension band is corrected; wherein the fourth frequency point is: W2+Wx.

11. The method according to claim 10, characterized in that The method further comprises: The bit stream is decoded to obtain at least one of the frequency domain envelope value of the spectrum signal between the first frequency point and the highest frequency point with bit allocation, the frequency domain envelope value of the spectrum signal between the starting frequency point of the preset bandwidth extension band and the second frequency point, the frequency domain envelope value of the spectrum signal between the third frequency point and the highest frequency point with bit allocation, and the frequency domain envelope value of the spectrum signal between the starting frequency point of the preset bandwidth extension band and the fourth frequency point.

12. The method according to claim 1, characterized in that The method further comprises: Noise filling is performed on a frequency band between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension frequency band.

13. The method according to claim 1, characterized in that The method further comprises: The audio frequency domain signal and the spectrum signal between the highest frequency point with bit allocation and the highest frequency point of the preset bandwidth extension band are added and combined, and then transformed from the frequency domain to the time domain to obtain a reconstructed audio time domain signal.

14. A communication device, characterized in that: The apparatus is configured in a decoding device, comprising: A transceiver module, used to receive a bit stream sent by an encoding device, and decode the bit stream to obtain a decoded audio frequency domain signal; A processing module, configured to predict, in response to the highest frequency point where bits of the audio frequency domain signal are allocated being lower than a starting frequency point of a preset bandwidth extension band, or the frequency band position where bits of the audio frequency domain signal are allocated being lower than a starting position of a preset bandwidth extension band, a spectrum signal between the highest frequency point where bits are allocated and the highest frequency point of the preset bandwidth extension band based on a spectrum signal within a predetermined frequency band range or a predetermined frequency point range in the audio frequency domain signal.

15. A communication device, characterized in that: The device includes a processor and a memory, wherein the memory A computer program is stored in the memory, and the processor executes the computer program stored in the memory to enable the device to perform the method according to any one of claims 1 to 13.

16. A communication device, characterized in that: include: A processor and an interface circuit, wherein the interface circuit is used to receive code instructions and transmit them to the processor; The processor is configured to run the code instructions to perform the method according to any one of claims 1 to 13.

17. A computer-readable storage medium storing instructions, which, when executed, enable the method according to any one of claims 1 to 13 to be implemented.

Images