Echo signal acquisition method and system, storage medium, equipment and program product
By setting up two digital audio interfaces in the digital signal processor to obtain the echo reference signal in advance, the problems of high hardware costs and delay in the prior art are solved, and the lower cost and more accurate echo cancellation effect is achieved, which is suitable for small electronic communication equipment.
Patent Information
- Application Number
- CN202510933727.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-07
- Publication Date
- 2025-08-15
AI Technical Summary
The existing echo cancellation algorithm relies on two audio codec chips in the uplink and downlink paths, resulting in high hardware costs and high latency, affecting the mobile communication experience.
By acquiring the microphone signal during the pick-up stage and setting up two digital audio interfaces in the digital signal processor, the echo reference signal is obtained in advance and processed, avoiding the delay in waiting for the echo reference signal to generate, reducing hardware cost and volume.
It realizes that echo reference signals can be processed in the sound pick-up stage, reducing hardware cost and volume, making it easier to adapt to small electronic communication equipment, and at the same time, the digital signals obtained are more accurate.
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Figure CN120496552A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of audio processing technology, and in particular to an echo signal acquisition method, system, storage medium, device and program product. Background Art
[0002] The mobile communications field includes hands-free communication functions, which are used in areas such as mobile phone speakerphone and car-mounted calls. When the microphone and speaker are physically too close or the gain of both is too large, a noticeable echo can be heard on the other end of the communication, resulting in poor communication quality.
[0003] Existing echo cancellation algorithms, when applied to the uplink channel, require the collection of downlink audio data as an echo reference signal. The algorithm then removes the downlink echo reference signal from the uplink audio data to achieve the desired echo cancellation effect. However, this process relies on two audio codec chips for both the uplink and downlink channels, resulting in high hardware costs and high latency in echo cancellation, impacting the mobile communication experience. Summary of the Invention
[0004] The purpose of the present application is to provide an echo signal acquisition method, system, computer-readable storage medium, electronic device and computer-readable storage medium, which can pre-process and store the echo reference signal before the uplink path signal arrives, thereby avoiding the delay of waiting for the echo reference signal to be generated.
[0005] To solve the above technical problems, the present application provides a method for obtaining an echo signal. The specific technical solution is as follows:
[0006] In the sound pickup phase, the input speech signal transmitted from the microphone to the codec is obtained;
[0007] During the playback phase, when the modem outputs the voice communication signal and the input voice signal, the audio signal is transmitted to the second digital audio interface via the first digital audio interface of the digital signal processor before being transmitted to the codec via the first digital audio interface of the digital signal processor;
[0008] Acquire an echo reference signal returned by the second digital audio interface.
[0009] Optionally, after obtaining the echo reference signal returned by the second digital audio interface, the method further includes:
[0010] In the digital signal processor, a preset echo cancellation algorithm and the input voice signal are applied to perform echo cancellation on the voice communication signal to obtain an echo-free voice communication signal.
[0011] Optionally, after obtaining the echo-free voice communication signal, the method further includes:
[0012] The echo-free voice communication signal is transmitted to the codec via the first digital audio interface, and the codec drives the speaker to play the sound after performing digital-to-analog signal conversion.
[0013] Optionally, also include:
[0014] During voice communication, a first digital audio interface and a second digital audio interface on the digital signal processor are enabled.
[0015] Optionally, enabling the first digital audio interface and the second digital audio interface on the digital signal processor during voice communication includes:
[0016] During voice communication, a first enable bit corresponding to the first digital audio interface and a second enable bit corresponding to the second digital audio interface included in a control register in the digital signal processor are set to an enabled state.
[0017] Optionally, also include:
[0018] Setting a first clock signal pin of the first digital audio interface to be connected to a second clock signal pin of the second digital audio interface;
[0019] Setting the data output signal pin of the first digital audio interface to be connected to the second data input signal pin of the second digital audio interface; the first data output signal pin of the first digital audio interface is connected to the codec;
[0020] It is set that the synchronization signal pins of the first digital audio interface and the second digital audio interface are connected, and the synchronization signal pins are used to synchronize the clock signal between the first digital audio interface and the second digital audio interface.
[0021] The present application also provides an echo signal acquisition system, comprising:
[0022] The sound pickup module is used to obtain the input voice signal transmitted from the microphone to the codec during the sound pickup stage;
[0023] a playback module configured to, during a playback phase, when the modem outputs the voice communication signal and the input voice signal, transmit the audio signal via the first digital audio interface of the digital signal processor to the second digital audio interface before transmitting the audio signal to the codec via the first digital audio interface of the digital signal processor;
[0024] The echo signal acquisition module is used to acquire the echo reference signal returned by the second digital audio interface.
[0025] The present application also provides a computer-readable storage medium having a computer program stored thereon, which implements the steps of the above-described method when executed by a processor.
[0026] The present application also provides an electronic device, including a memory and a processor, wherein a computer program is stored in the memory, and the processor implements the steps of the above-mentioned method when calling the computer program in the memory.
[0027] The present application provides an echo signal acquisition method, comprising: in a sound pickup phase, acquiring an input voice signal transmitted from a microphone to a codec; in a sound playback phase, when a modem outputs a voice communication signal and the input voice signal, transmitting the audio signal to a second digital audio interface via a first digital audio interface of a digital signal processor before transmitting the audio signal to the codec via the first digital audio interface; and acquiring an echo reference signal returned by the second digital audio interface.
[0028] This application provides two digital audio interfaces, a first digital audio interface and a second digital audio interface, and acquires an echo reference signal through the second digital audio interface. This allows the echo reference signal to be processed and stored by a digital signal processor before it arrives at the sound pickup stage, enabling it to participate in the echo cancellation algorithm in advance, avoiding the delay of waiting for the echo reference signal to be processed and generated. There is no need to use a separate codec chip to perform digital-to-analog signal conversion on the echo reference signal. Only three wires need to be added to connect the second digital audio interface, reducing hardware usage cost and size, and facilitating adaptation to small electronic communication devices. Furthermore, since there is no need to use a separate codec chip to perform digital-to-analog signal conversion, the digital signal can be directly acquired for echo cancellation processing. Compared with existing solutions that collect analog signals for processing, the acquired digital signal is more accurate.
[0029] The present application also provides an echo signal acquisition system, a computer-readable storage medium, an electronic device, and a computer program product, which have the above-mentioned beneficial effects and are not described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS
[0030] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without any creative work.
[0031] Figure 1 A flowchart of a method for acquiring an echo signal provided in an embodiment of the present application;
[0032] Figure 2A schematic diagram of the hardware structure provided in the embodiment of the present application;
[0033] Figure 3 A schematic diagram of the structure of an echo signal acquisition system provided in an embodiment of the present application;
[0034] Figure 4 This is a structural diagram of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION
[0035] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.
[0036] The object information involved in this application, including but not limited to the object device information, the object personal information, etc., and data, including but not limited to data used for analysis, stored data, displayed data, etc., are all information and data authorized by the object or fully authorized by all parties, and the collection, use and processing of relevant data must comply with the laws, regulations and standards of relevant countries and regions.
[0037] See also Figure 1 , Figure 1 A flowchart of a method for acquiring an echo signal provided in an embodiment of the present application, the method comprising:
[0038] S101: In the sound pickup phase, an input voice signal transmitted from a microphone to a codec is obtained;
[0039] S102: During the playback phase, when the modem outputs the voice communication signal and the input voice signal, before transmitting the audio signal to the codec via the first digital audio interface of the digital signal processor, transmitting the audio signal to the second digital audio interface via the first digital audio interface;
[0040] S103: Acquire an echo reference signal transmitted back by the second digital audio interface.
[0041] When applying this embodiment, the original upstream and downstream paths are kept enabled. The upstream path is the sound pickup path, which includes microphone → codec → digital audio interface → upstream path 2 → echo cancellation algorithm → upstream path 1 → modem. The downstream path is the sound playback path, which includes modem → downstream path 1 → echo cancellation algorithm → downstream path 2 → digital audio interface → codec → speaker.
[0042] On this basis, it is necessary to open the echo reference signal acquisition path required for applying this application in advance and enable at least two digital audio interfaces.
[0043] Subsequently, during the sound pickup phase, the input voice signal transmitted from the microphone to the codec needs to be captured. During the sound playback phase, the voice communication signal output by the modem and the input voice signal are transmitted along a predetermined path. In a preferred implementation, signal transmission priority and order can also be set to ensure that the voice communication signal is preferentially transmitted via the first digital audio interface to the second digital audio interface without interference from other signals. For example, an interrupt-driven approach can be employed. When the modem outputs a voice communication signal, a corresponding interrupt handler is triggered, immediately transmitting the signal via the digital audio interface.
[0044] In order to better illustrate the signal transmission process involved in this application, see Figure 2 , Figure 2 This is a schematic diagram of the hardware structure provided in the embodiment of the present application. Figure 2 It includes the following structures and signal transmission paths:
[0045] Rx1 refers to the downlink channel, which includes the path for transmitting received signals from the modem to subsequent processing modules (such as the echo cancellation algorithm module). Correspondingly, TX represents the uplink channel.
[0046] Codec is a coder-decoder that converts analog signals (such as sound signals input by a microphone) into digital signals for easy processing by digital systems. At the same time, it also converts digital signals (such as signals received from a digital audio interface) into analog signals to drive the speakers to produce sound.
[0047] A modem is used to convert signals between analog communication channels (such as telephone lines) and digital devices. On the transmitting end, it modulates digital signals into analog signals suitable for transmission over analog channels; on the receiving end, it demodulates the received analog signals back into digital signals.
[0048] In the downlink, the signal is transmitted from the modem through Rx1. The modem first receives the analog signal (such as the voice signal transmitted through the telephone line) and demodulates it into a digital signal.
[0049] The digital signal enters the echo cancellation algorithm module along the Rx1 channel. The algorithm processes the signal to eliminate any echo. The processed signal is then transmitted to digital audio interface A via Rx2. Digital audio interface A acts as a relay and interface matching device, transmitting the signal to the codec. The codec converts the digital signal into an analog signal, which then drives the speaker to produce sound.
[0050] In the uplink, the microphone picks up the user's voice signal, generates an analog signal, and sends it to the codec. The codec converts the analog signal into a digital signal and transmits it through digital audio interface A. The digital signal travels along the Tx2 channel and enters the echo cancellation algorithm module. The echo cancellation algorithm further processes the signal to prevent local voice signals from interfering with communications. The processed signal is transmitted to the modem through Tx1. The modem modulates the digital signal into an analog signal suitable for transmission over an analog channel and then transmits it.
[0051] In the echo reference signal acquisition method involved in this application, the digital signal received by the modem is transmitted to the digital signal processor via Rx1. The digital signal processor includes an echo cancellation algorithm for performing echo signal cancellation. The digital signal processor then sends the signal to the digital audio interface A via Rx2, and then transmits it from digital audio interface A to digital audio interface B.
[0052] The digital audio interface B transmits the echo reference signal Rxref to the echo cancellation algorithm module. The echo reference signal is used by the echo cancellation algorithm to more accurately identify and cancel the echo.
[0053] also, Figure 2 It also includes the following pins of digital audio interface such as CLK, SYNC, DOUT, DIN, etc.:
[0054] The CLK (clock signal) pin provides a clock signal for digital audio interfaces, synchronizing data transmission. The clock signal determines the rate and cadence of data transmission, ensuring that the sender and receiver can correctly read and process the data. The clock signal is typically a periodic square wave whose frequency is related to the audio data sampling rate. For example, in a common I2S audio interface, the clock signal frequency is typically 256 or 384 times the audio sampling rate.
[0055] The SYNC (synchronization signal) pin is used for frame synchronization, synchronizing multiple digital audio signals or the clock signals of multiple audio devices to ensure that the audio data maintains the correct frame structure and sequence during transmission. The SYNC signal is typically a short pulse signal that generates a synchronization pulse at the beginning of each audio frame. The receiver detects the SYNC signal to determine the starting position of the audio data frame.
[0056] The DOUT (data output pin) is used to output digital audio data from the device to an external receiving device, such as from a DSP to a codec or other audio processing chip. The DOUT pin transmits audio data bit by bit or word by word according to a specific data format and protocol, under the control of clock and synchronization signals, usually in serial mode. The DOUT pin is a key channel for audio data output, and its performance and stability directly affect the quality of the audio signal and the reliability of transmission.
[0057] The DIN (data input) pin receives digital audio data from external devices, such as analog-to-digital converted audio data from a codec or audio signals from other audio sources. Controlled by clock and synchronization signals, the DIN pin reads the received audio data bit by bit or word by word into the device for processing or storage according to the corresponding data format and protocol. The DIN pin is the key entry point for audio data input, ensuring the correct reception and processing of external audio signals.
[0058] This application provides two digital audio interfaces, a first digital audio interface and a second digital audio interface, and acquires an echo reference signal through the second digital audio interface. This allows the echo reference signal to be processed and stored by a digital signal processor before it arrives at the sound pickup stage, enabling it to participate in the echo cancellation algorithm in advance, avoiding the delay of waiting for the echo reference signal to be processed and generated. There is no need to use a separate codec chip to perform digital-to-analog signal conversion on the echo reference signal. Only three wires need to be added to connect the second digital audio interface, reducing hardware usage cost and size, and facilitating adaptation to small electronic communication devices. Furthermore, since there is no need to use a separate codec chip to perform digital-to-analog signal conversion, the digital signal can be directly acquired for echo cancellation processing. Compared with existing solutions that collect analog signals for processing, the acquired digital signal is more accurate.
[0059] In a feasible implementation manner, before executing the echo signal acquisition method disclosed in this application, at least one of the following preparatory steps may be performed:
[0060] The first step is to check the hardware connection to ensure that the digital audio interface pins (such as CLK, SYNC, DOUT, and DIN) are properly connected to external devices (such as a codec). These pins transmit clock signals, synchronization signals, data output, and data input. Check that the power and ground wires are properly connected to provide a stable power supply for the digital audio interface.
[0061] The second type: clock configuration, which is used to configure the operating clock of the digital audio interface. This typically involves setting the processor's internal clock divider or clock source to generate a clock frequency suitable for the digital audio interface. For example, in some processors, the clock control register can be set to select the clock source of the digital audio interface (such as an internal oscillator or an external clock input) and divide the clock as needed. Assuming that a 48kHz sampling rate clock is required for the first digital audio interface, the appropriate division factor is calculated based on the specific clock tree structure and clock source frequency, and the divided clock signal is then provided to the first digital audio interface.
[0062] The third method involves register configuration (digital audio interfaces A and B, corresponding to the first and second digital audio interfaces) to enable the interfaces. In the processor's digital audio interface control registers, locate the enable bits corresponding to digital audio interfaces A and B and set them to enabled. For example, for digital audio interface A, set the "ENABLE_A" bit in its control register to 1; for digital audio interface B, set the "ENABLE_B" bit to 1.
[0063] The fourth type: format configuration, which is used to set the data format of the digital audio interface, including data width (such as 16-bit, 24-bit, etc.), data format (such as I2S format, left-aligned format, etc.), sampling rate, etc.
[0064] Fifth: Interrupt and DMA configuration. If you need to use interrupts or DMA (direct memory access) to handle audio data transmission, you also need to configure the corresponding interrupt enable bit or DMA request signal. This can improve data transmission efficiency and reduce the burden on the CPU.
[0065] The sixth method is to write or configure a software driver to operate the digital audio interface. In the driver, data is sent and received by reading and writing the digital audio interface's registers. For transmission, audio data is written to the digital audio interface's transmit data register; for reception, audio data is read from the receive data register. A data buffer is configured to temporarily store transmit and receive data. Properly setting the buffer size and number can prevent data overflow or loss.
[0066] Seventh: Debugging and verification. Use debugging tools (such as logic analyzers and oscilloscopes) to check the signal integrity of the digital audio interface, including whether the waveforms of the clock and data signals are normal. Verify the proper function of the digital audio interface by sending and receiving known audio test signals. For example, send a sine wave audio signal of a specific frequency and check whether the signal can be correctly decoded and restored at the receiving end.
[0067] See also Figure 3 , Figure 3 This is a schematic diagram of the structure of an echo signal acquisition system provided in an embodiment of the present application, the system comprising:
[0068] The sound pickup module is used to obtain the input voice signal transmitted from the microphone to the codec during the sound pickup stage;
[0069] a playback module configured to, during a playback phase, when the modem outputs the voice communication signal and the input voice signal, transmit the audio signal via the first digital audio interface of the digital signal processor to the second digital audio interface before transmitting the audio signal to the codec via the first digital audio interface of the digital signal processor;
[0070] The echo signal acquisition module is used to acquire the echo reference signal returned by the second digital audio interface.
[0071] The present application also provides an embodiment corresponding to a computer-readable storage medium. The computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of the method described in the above method embodiment.
[0072] The present application also provides a corresponding embodiment of a computer program product. The computer program product includes a computer program, which, when executed by a processor, implements the steps of the method described in the above method embodiment.
[0073] It is understandable that if the method in the above embodiment is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium and executes all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, and other media that can store program code.
[0074] The computer-readable storage medium provided in this embodiment includes the above-mentioned method, and the effect is the same as above.
[0075] This application also provides an electronic device, see Figure 4 , a structural diagram of an electronic device provided in an embodiment of the present application, such as Figure 4 As shown, a processor 1410 and a memory 1420 may be included.
[0076] The processor 1410 may include one or more processing cores, such as a 4-core processor, an 8-core processor, etc. The processor 1410 may be implemented in at least one hardware form of DSP (Digital Signal Processing), FPGA (Field-Programmable Gate Array), or PLA (Programmable Logic Array). The processor 1410 may also include a main processor and a coprocessor. The main processor is a processor for processing data in the awake state, also known as a CPU (Central Processing Unit); the coprocessor is a low-power processor for processing data in the standby state. In some embodiments, the processor 1410 may be integrated with a GPU (Graphics Processing Unit), which is responsible for rendering and drawing the content to be displayed on the display screen. In some embodiments, the processor 1410 may also include an AI (Artificial Intelligence) processor, which is used to process computing operations related to machine learning.
[0077] The memory 1420 may include one or more computer-readable storage media, which may be non-transitory. The memory 1420 may also include a high-speed random access memory, and a non-volatile memory, such as one or more disk storage devices, flash memory storage devices. In this embodiment, the memory 1420 is at least used to store the following computer program 1421, wherein, after the computer program is loaded and executed by the processor 1410, it can implement the relevant steps in the method performed by the electronic device side disclosed in any of the aforementioned embodiments. In addition, the resources stored in the memory 1420 may also include an operating system 1422 and data 1423, etc., and the storage method may be temporary storage or permanent storage. Among them, the operating system 1422 may include Windows, Linux, Android, etc.
[0078] In some embodiments, the electronic device may further include a display screen 1430 , an input / output interface 1440 , a communication interface 1450 , a sensor 1460 , a power supply 1470 , and a communication bus 1480 .
[0079] certainly, Figure 4 The structure of the electronic device shown does not constitute a limitation on the electronic device in the embodiment of the present application. In actual applications, the electronic device may include Figure 4 More or fewer components than shown, or combinations of certain components.
[0080] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Reference can be made to the common and similar parts between the various embodiments. For the systems provided in the embodiments, since they correspond to the methods provided in the embodiments, the description is relatively simple, and the relevant parts can be referred to the method description.
[0081] This document uses specific examples to illustrate the principles and implementation methods of this application. The description of the above examples is only intended to help understand the method and core ideas of this application. It should be noted that for those skilled in the art, without departing from the principles of this application, various improvements and modifications can be made to this application, and such improvements and modifications also fall within the scope of protection of this application.
[0082] It should also be noted that, in this specification, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variants thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus comprising the element.
Claims
1. A method for acquiring an echo signal, characterized in that: include: In the sound pickup phase, the input speech signal transmitted from the microphone to the codec is obtained; During the playback phase, when the modem outputs the voice communication signal and the input voice signal, the audio signal is transmitted to the second digital audio interface via the first digital audio interface of the digital signal processor before being transmitted to the codec via the first digital audio interface of the digital signal processor; Acquire an echo reference signal returned by the second digital audio interface.
2. The echo signal acquisition method according to claim 1, wherein: After obtaining the echo reference signal returned by the second digital audio interface, the method further includes: In the digital signal processor, a preset echo cancellation algorithm and the input voice signal are applied to perform echo cancellation on the voice communication signal to obtain an echo-free voice communication signal.
3. The echo signal acquisition method according to claim 2, characterized in that: After obtaining the echo-free voice communication signal, the method further includes: The echo-free voice communication signal is transmitted to the codec via the first digital audio interface, and the codec drives the speaker to play the sound after performing digital-to-analog signal conversion.
4. The echo signal acquisition method according to claim 1, wherein: Also includes: During voice communication, a first digital audio interface and a second digital audio interface on the digital signal processor are enabled.
5. The echo signal acquisition method according to claim 4, characterized in that: The enabling of the first digital audio interface and the second digital audio interface on the digital signal processor during voice communication includes: During voice communication, a first enable bit corresponding to the first digital audio interface and a second enable bit corresponding to the second digital audio interface included in a control register in the digital signal processor are set to an enabled state.
6. The echo signal acquisition method according to claim 5, characterized in that: Also includes: Setting a first clock signal pin of the first digital audio interface to be connected to a second clock signal pin of the second digital audio interface; Setting the data output signal pin of the first digital audio interface to be connected to the second data input signal pin of the second digital audio interface; the first data output signal pin of the first digital audio interface is connected to the codec; It is set that the synchronization signal pins of the first digital audio interface and the second digital audio interface are connected, and the synchronization signal pins are used to synchronize the clock signal between the first digital audio interface and the second digital audio interface.
7. An echo signal acquisition system, characterized in that: include: The sound pickup module is used to obtain the input voice signal transmitted from the microphone to the codec during the sound pickup stage; a playback module configured to, during a playback phase, when the modem outputs the voice communication signal and the input voice signal, transmit the audio signal via the first digital audio interface of the digital signal processor to the second digital audio interface before transmitting the audio signal to the codec via the first digital audio interface of the digital signal processor; The echo signal acquisition module is used to acquire the echo reference signal returned by the second digital audio interface.
8. An electronic device, characterized in that: include: Memory for storing computer programs; A processor, configured to implement the steps of the echo signal acquisition method according to any one of claims 1 to 6 when executing the computer program.
9. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, which implements the steps of the method according to any one of claims 1 to 6 when executed.
10. A computer program product, characterized in that The method comprises a computer program, which implements the steps of the echo signal acquisition method according to any one of claims 1 to 6 when the computer program is executed.