CN113179468A

CN113179468A - Audio synchronous playing method, device, equipment and storage medium

Info

Publication number: CN113179468A
Application number: CN202110468174.0A
Authority: CN
Inventors: 严可
Original assignee: Shenzhen Goodix Technology Co Ltd
Current assignee: Shenzhen Goodix Technology Co Ltd
Priority date: 2020-11-05
Filing date: 2020-11-05
Publication date: 2021-07-27
Anticipated expiration: 2040-11-05
Also published as: CN112039623B; CN113179468B; CN112039623A

Abstract

The embodiment of the application provides an audio synchronous playing method, device, equipment and storage medium, and relates to the field of data processing. The method is applied to a first audio playing device, and comprises the following steps: acquiring state information of a Bluetooth controller in the first audio playing device and Bluetooth time of the Bluetooth controller, and determining local Bluetooth time of the first audio playing device according to the state information and the Bluetooth time acquired from the Bluetooth controller; estimating the absolute time of the second audio playing device or the audio providing device based on the local Bluetooth time of the first audio playing device and the offset time of the local Bluetooth time of the first audio playing device relative to the local Bluetooth time of the second audio playing device or the local Bluetooth time of the audio providing device; and synchronously playing the audio signal provided by the audio providing equipment with the second audio playing equipment based on the estimated absolute time. By the embodiment of the application, the synchronous precision of audio playing can be effectively improved.

Description

Audio synchronous playing method, device, equipment and storage medium

Technical Field

The embodiment of the application relates to the field of data processing, and in particular relates to an audio synchronous playing method and device, an electronic device and a computer readable storage medium.

Background

With the development of multimedia technology, in more and more application scenes, a plurality of devices are required to form a synchronous playing system to perform audio synchronous playing, so that the plurality of devices can synchronously make sound, and functions and effects which are difficult to realize by a single device can be realized. For example, a True Wireless Stereo (TWS) bluetooth headset performs audio synchronous playback, and can achieve the effect of two-channel surround sound. In addition, the winding and pulling of the earphone wire and the stethoscope effect can be avoided, so that the experience of the user in using the earphone is effectively improved. For another example, two bluetooth speakers can play audio synchronously, so that the effect of two-channel surround sound can be achieved.

The TWS Bluetooth headset comprises two Bluetooth headsets which are not physically connected and are a Bluetooth master headset and a Bluetooth slave headset respectively, so that wired troubles are completely eliminated, and convenience is brought to life of people. Because the bluetooth master earphone and the bluetooth slave earphone operate independently, the audio playing synchronization can not be realized through wired connection, and therefore, how to realize the audio synchronous playing of the bluetooth master earphone and the bluetooth slave earphone becomes a technical problem which needs to be solved urgently. In the prior art, software compensation is mostly adopted to realize synchronous audio playing of a bluetooth master earphone and a bluetooth slave earphone. However, software compensation lacks hardware support, and audio playing synchronization delay is large, so that the accuracy of audio playing synchronization cannot be effectively improved. Similar to the TWS bluetooth headset, the bluetooth speaker also has a technical problem that the precision of audio synchronous playing cannot be effectively improved. Therefore, how to effectively improve the precision of audio playing synchronization becomes a technical problem which needs to be solved urgently at present.

Disclosure of Invention

In view of the above, an objective of the present invention is to provide an audio synchronous playing method, device and chip, so as to solve at least the above technical problems.

According to a first aspect of the embodiments of the present application, there is provided an audio synchronous playing method applied to a first audio playing device, the method including: acquiring state information of a Bluetooth controller in the first audio playing device and Bluetooth time of the Bluetooth controller in the first audio playing device, and determining local Bluetooth time of the first audio playing device according to the state information and the Bluetooth time acquired from the Bluetooth controller in the first audio playing device, wherein the state information is information for indicating the state of the Bluetooth controller in the first audio playing device; estimating the absolute time of a second audio playing device based on the local Bluetooth time of the first audio playing device and the offset time of the local Bluetooth time of the first audio playing device relative to the local Bluetooth time of the second audio playing device, and synchronously playing an audio signal provided by an audio providing device with the second audio playing device based on the estimated absolute time; or estimating the absolute time of the audio providing equipment based on the local Bluetooth time of the first audio playing equipment and the offset time of the local Bluetooth time of the first audio playing equipment relative to the local Bluetooth time of the audio providing equipment, and synchronously playing the audio signal provided by the audio providing equipment with the second audio playing equipment based on the estimated absolute time; the second audio playing device is paired with the first audio playing device and connected with the audio providing device through common Bluetooth.

According to a second aspect of the embodiments of the present application, there is provided an audio synchronized playback apparatus, the apparatus including: the device comprises a timer in communication connection with a Bluetooth controller and a first audio playing module in communication connection with the timer, wherein the timer is used for determining the local Bluetooth time of the first audio playing module based on state information of the Bluetooth controller and the Bluetooth time acquired from the Bluetooth controller, the state information is information used for indicating the state of the Bluetooth controller, and the absolute time of a second audio playing module is estimated based on the local Bluetooth time of the first audio playing module and the offset time of the local Bluetooth time of the first audio playing module relative to the local Bluetooth time of the second audio playing module; or estimating the absolute time of the audio providing device based on the local bluetooth time of the first audio playing module and the offset time of the local bluetooth time of the first audio playing module relative to the local bluetooth time of the audio providing device, wherein the first audio playing module and the second audio playing module share the same bluetooth to connect the audio providing device; the first audio playing module is configured to play the audio signal provided by the audio providing device synchronously with the second audio playing module based on the estimated absolute time.

According to a third aspect of the embodiments of the present application, there is provided an audio synchronized playback apparatus, the apparatus including: the device comprises a timer in communication connection with a Bluetooth controller and a first audio playing module in communication connection with the timer, wherein the timer is used for determining local Bluetooth time of the first audio playing module based on state information of the Bluetooth controller and Bluetooth time acquired from the Bluetooth controller, the state information is information used for indicating the state of the Bluetooth controller, absolute time of a second audio playing module is estimated based on the local Bluetooth time of the first audio playing module and offset time of the local Bluetooth time of the first audio playing module relative to the local Bluetooth time of the second audio playing module, and an audio playing synchronization signal is generated based on the estimated absolute time; or the audio playing synchronization signal is generated based on the estimated absolute time and the local bluetooth time of the first audio playing module and the offset time of the local bluetooth time of the first audio playing module relative to the local bluetooth time of the audio providing device, wherein the first audio playing module and the second audio playing module share the same bluetooth to connect the audio providing device; the first audio playing module is configured to play the audio signal provided by the audio providing device synchronously with the second audio playing module based on the audio playing synchronization signal.

According to a fourth aspect of embodiments of the present application, a computer-readable storage medium has stored thereon a computer program, which when executed by a processor implements the audio synchronized playback method according to the first aspect of embodiments of the present application.

According to a fifth aspect of the embodiments of the present application, there is provided an electronic device, which includes the audio synchronous playing apparatus according to the second aspect or the third aspect of the embodiments of the present application.

In the embodiment of the application, the local bluetooth time of the first audio playing device is used for predicting the absolute time of the second audio playing device or the audio providing device paired with the first audio playing device, so that the first audio playing device can obtain the absolute time of the second audio playing device or the audio providing device, and further synchronously play the audio signal provided by the audio providing device with the second audio playing device based on the predicted absolute time, in addition, the local bluetooth time of the first audio playing device is obtained based on the bluetooth time of the bluetooth controller in the first audio playing device, and the inside of the bluetooth controller is provided with a clock accurate to microsecond, therefore, the precision of audio synchronous playing of the first audio playing device and the second audio playing device can be effectively improved, and the antenna is not required to be additionally occupied for receiving and sending the audio playing synchronization signal.

Drawings

Some specific embodiments of the present application will be described in detail hereinafter by way of illustration and not limitation with reference to the accompanying drawings. The same reference numbers in the drawings identify the same or similar elements or components. Those skilled in the art will appreciate that the drawings are not necessarily drawn to scale. In the drawings:

fig. 1A is a flowchart of an audio synchronous playing method according to an embodiment of the present application;

fig. 1B is a first schematic diagram of a first audio playing device and a second audio playing device in a forwarding mode of a classic bluetooth protocol according to an embodiment of the present application;

fig. 1C is a second schematic diagram of a first audio playing device and a second audio playing device in a forwarding mode of a classic bluetooth protocol according to an embodiment of the present application;

fig. 2A is a flowchart of an audio synchronous playing method according to a second embodiment of the present application;

fig. 2B is a schematic diagram of a second audio playback device and a first audio playback device in a listening mode of a classic bluetooth protocol according to a second embodiment of the present application;

fig. 3A is a flowchart of an audio synchronous playing method according to a third embodiment of the present application;

fig. 3B is a connection timing diagram of a synchronous connection stream communication link according to a third embodiment of the present application;

fig. 3C is a schematic diagram of synchronization point alignment of a synchronous connection stream communication link according to a third embodiment of the present application;

fig. 3D is a schematic diagram of a synchronous connection streaming communication link of an audio playing device according to a third embodiment of the present application;

fig. 3E is a schematic diagram of the first audio playing device and the second audio playing device in a synchronization mode of the bluetooth low energy protocol according to the third embodiment of the present application;

fig. 3F is a schematic diagram of interaction event counting parameters of the first audio playing device and the second audio playing device according to the third embodiment of the present application;

fig. 4 is a schematic structural diagram of an audio synchronous playback device according to a fourth embodiment of the present application;

fig. 5 is a schematic structural diagram of an audio synchronous playback device according to a fifth embodiment of the present application;

fig. 6 is a schematic structural diagram of an electronic device according to a sixth embodiment of the present application.

Detailed Description

The following further describes a specific implementation manner of the embodiment of the invention with reference to the drawings of the embodiment of the invention.

Referring to fig. 1A, a flowchart of an audio synchronous playing method according to an embodiment of the present application is shown.

The audio synchronous playing method provided by the embodiment can be applied to a forwarding mode and a listening mode of a classic bluetooth protocol and a synchronous mode of a low-power-consumption bluetooth protocol. The present embodiment describes the audio synchronous playing method provided by the present embodiment in detail from the perspective of the first audio playing device. Specifically, the audio synchronous playing method provided by this embodiment includes the following steps:

in step S101, state information of a bluetooth controller in the first audio playing device and bluetooth time of the bluetooth controller in the first audio playing device are obtained, and local bluetooth time of the first audio playing device is determined according to the state information and the bluetooth time obtained from the bluetooth controller in the first audio playing device.

In this embodiment, the bluetooth controller may be understood as a chip for controlling bluetooth communication or data transmission of the first audio playback device. The state information may be understood as information indicating a state in which the bluetooth controller is located, for example, information indicating that the bluetooth controller is in an operating state, information indicating that the bluetooth controller is in a sleep state, and the like. The local bluetooth time of the first audio playback device may be understood as the bluetooth communication duration of the first audio playback device that is locally timed by the first audio playback device after the first audio playback device accesses the bluetooth link. Specifically, the timer of the first audio playing device obtains the state information of the bluetooth controller in the first audio playing device and the bluetooth time of the bluetooth controller in the first audio playing device from the bluetooth controller of the first audio playing device, and determines the local bluetooth time of the first audio playing device according to the state information and the bluetooth time obtained from the bluetooth controller in the first audio playing device.

In some optional embodiments, when the local bluetooth time of the first audio playing device is determined according to the state information and the bluetooth time acquired from the bluetooth controller in the first audio playing device, if the state information is information indicating that the bluetooth controller is in an operating state, it is determined that the local bluetooth time of the first audio playing device is the bluetooth time sampled by the timer of the first audio playing device from the bluetooth controller. The bluetooth time can be understood as the bluetooth communication duration of the first audio playing device timed by the bluetooth controller of the first audio playing device. Therefore, when the Bluetooth controller in the first audio playing device is in an operating state, the local Bluetooth time of the first audio playing device can be accurately determined by sampling the Bluetooth time from the Bluetooth controller.

In some optional embodiments, when the local bluetooth time of the first audio playing device is determined according to the state information and the bluetooth time acquired from the bluetooth controller in the first audio playing device, if the state information is information indicating that the bluetooth controller is in a sleep state, the local bluetooth time of the first audio playing device is determined based on the time of low power consumption of the first audio playing device and the bluetooth time sampled from the bluetooth controller at the last time. The low power consumption time is the duration of the Bluetooth controller in a dormant state. Therefore, when the Bluetooth controller in the first audio playing device is in a dormant state, the local Bluetooth time of the first audio playing device can be accurately determined through the low power consumption time of the first audio playing device and the Bluetooth time sampled from the Bluetooth controller at the last time.

In a specific example, when the local bluetooth time of the first audio playback device is determined based on the time-to-low power of the first audio playback device and the bluetooth time sampled from the bluetooth controller at the latest time, the time-to-low power of the first audio playback device is added to the bluetooth time sampled from the bluetooth controller at the latest time to obtain an addition result, and the addition result is determined to be the local bluetooth time of the first audio playback device.

In a specific example, the bluetooth communication adopts a time division multiplexing communication mechanism, and a bluetooth clock accurate to microsecond is provided inside a bluetooth controller. In addition, because the bluetooth controller can be in a sleep state after receiving the expected bluetooth data, and when the bluetooth controller is in the sleep state, the timer of the first audio playing device cannot sample the bluetooth time of the bluetooth controller, a low power consumption clock is designed inside the first audio playing device for timing the time length of the bluetooth controller in the sleep state. Specifically, when the bluetooth controller starts to sleep, the low power consumption clock starts to count from zero (e.g., 1 is added every 0.5 us), and then the low power consumption time of the first audio playing device can be obtained, and the bluetooth time of the bluetooth controller stops being sampled. And after the Bluetooth controller finishes dormancy, the low-power-consumption clock stops counting, and the timer of the first audio playing device continues to sample the Bluetooth time of the Bluetooth controller.

In step S102, the absolute time of the second audio playing device is estimated based on the local bluetooth time of the first audio playing device and the offset time of the local bluetooth time of the first audio playing device relative to the local bluetooth time of the second audio playing device, or the absolute time of the audio providing device is estimated based on the local bluetooth time of the first audio playing device and the offset time of the local bluetooth time of the first audio playing device relative to the local bluetooth time of the audio providing device.

In this embodiment, the audio providing device is a provider of an audio source, and the audio providing device may be any device having an arithmetic processing capability. The audio providing device includes a bluetooth controller supporting a bluetooth protocol, which may be, but is not limited to, a single-mode bluetooth controller supporting a classic bluetooth protocol or a bluetooth low energy protocol, or a dual-mode bluetooth controller also supporting a bluetooth low energy protocol, as long as it is compatible with bluetooth communication with the audio playing device. The audio providing apparatus may also have a voice communication function. For example, the audio providing device may be a mobile phone terminal, a tablet computer, an in-vehicle device, an industrial device, and the like. The second audio playing device is paired with the first audio playing device and connected with the audio providing device through common Bluetooth. Pairing the second audio playback device with the first audio playback device may be understood as the second audio playback device being paired with and matching the first audio playback device. For example, a user listens to music played in a mobile phone terminal through a TWS bluetooth headset, the mobile phone terminal is connected with two of the TWS bluetooth headsets in a bluetooth manner, the first audio playing device may be a master headset in the TWS bluetooth headset, the second audio playing device may be a slave headset in the TWS bluetooth headset, and the audio providing device is the mobile phone terminal. For another example, when the first audio playback device is a bluetooth slave in a TWS bluetooth headset bluetooth-connected to the mobile terminal, the second audio playback device may be a bluetooth master in a TWS bluetooth headset bluetooth-connected to the mobile terminal. For another example, when the first audio playing device is a bluetooth master speaker connected to the mobile phone terminal via bluetooth, the second audio playing device may be a bluetooth slave speaker connected to the mobile phone terminal via bluetooth.

In some optional embodiments, the first audio playback device and the second audio playback device are in a forwarding mode of a classic bluetooth protocol. When the absolute time of the second audio playing device is estimated based on the local Bluetooth time of the first audio playing device and the offset time of the local Bluetooth time of the first audio playing device relative to the local Bluetooth time of the second audio playing device, estimating the local Bluetooth time of the second audio playing device based on the local Bluetooth time of the first audio playing device and the offset time of the local Bluetooth time of the first audio playing device relative to the local Bluetooth time of the second audio playing device, and determining the estimated local Bluetooth time of the second audio playing device as the estimated absolute time. Therefore, the estimated local Bluetooth time of the second audio playing device can be determined to be the estimated absolute time through the local Bluetooth time of the first audio playing device and the offset time of the local Bluetooth time of the first audio playing device relative to the local Bluetooth time of the second audio playing device.

In a specific example, since the first audio playing device and the second audio playing device are in a forwarding mode of a classic bluetooth protocol, the first audio playing device may be a bluetooth slave earphone or a bluetooth slave speaker, and the second audio playing device may be a bluetooth master earphone or a bluetooth master speaker. Considering that the bluetooth communication device has frequency deviation, the bluetooth protocol specification requires that the slave device in bluetooth communication calculates the offset time of the local bluetooth time of the slave device relative to the local bluetooth time of the master device when receiving expected bluetooth data, and estimates the local bluetooth time of the master device according to the calculated offset time so as to ensure that the bluetooth time difference between the master device and the slave device does not exceed 1us at the time of receiving data. The offset time of the local bluetooth time of the first audio playback device relative to the local bluetooth time of the second audio playback device may be obtained from bluetooth controller firmware. The bluetooth controller firmware may be understood as an application installed in the bluetooth controller for calculating an offset time of the local bluetooth time of the first audio playback device relative to the local bluetooth time of the second audio playback device. Specifically, each time the bluetooth controller of the first audio playback device receives expected bluetooth data (e.g., an audio signal) from the second audio playback device, the bluetooth controller firmware may determine an expected arrival time of the expected bluetooth data from the second audio playback device to the first audio playback device according to a bluetooth protocol specification; and comparing the expected arrival time with the actual arrival time of the expected Bluetooth data from the second audio playing device to the first audio playing device to obtain the offset time of the local Bluetooth time of the first audio playing device relative to the local Bluetooth time of the second audio playing device. More specifically, the bluetooth controller firmware may precisely calculate a local bluetooth time at which the expected bluetooth data is expected to arrive according to a bluetooth protocol specification, calculate a difference between the local bluetooth time at which the expected bluetooth data is expected to arrive and the local bluetooth time at which the expected bluetooth data is actually arrived, and determine the difference as an offset time of the local bluetooth time of the first audio playback device relative to the local bluetooth time of the second audio playback device. Therefore, by comparing the local Bluetooth time of the expected Bluetooth data expected to arrive with the local Bluetooth time of the expected Bluetooth data actually arriving, the offset time of the local Bluetooth time of the first audio playing device relative to the local Bluetooth time of the second audio playing device can be accurately obtained.

In a specific example, when estimating the local bluetooth time of the second audio playing device, the local bluetooth time of the first audio playing device and the offset time of the local bluetooth time of the first audio playing device relative to the local bluetooth time of the second audio playing device may be added to obtain the estimated local bluetooth time of the second audio playing device.

In step S103, based on the estimated absolute time, the audio signal provided by the audio providing device is played synchronously with the second audio playing device.

In some optional embodiments, when the audio signal provided by the audio providing device is played synchronously with the second audio playing device based on the estimated absolute time, performing a modulo operation on the estimated local bluetooth time of the second audio playing device to obtain the synchronous playing time of the audio signals of the first audio playing device and the second audio playing device; and synchronously playing the audio signal provided by the audio providing equipment with the second audio playing equipment based on the synchronous playing time. Therefore, the synchronous playing time of the audio signals of the first audio playing device and the second audio playing device is obtained by performing the modulus operation on the estimated local Bluetooth time of the second audio playing device, and the audio playing module in the first audio playing device can conveniently read the audio signals at one time.

In a specific example, the first audio playing device may perform a modulo operation on the estimated local bluetooth time of the second audio playing device by 2^32, and store the obtained synchronous playing time of the audio signals of the first audio playing device and the second audio playing device by using a 32-bit register, so as to facilitate the audio playing module in the first audio playing device to read at one time. Similarly, the second audio playing device may also perform modulo operation on the local bluetooth time of the second audio playing device by 2^32, and store the synchronous playing time of the audio signals of the first audio playing device and the second audio playing device obtained by the second audio playing device by using a 32-bit register, so as to facilitate the audio playing module in the second audio playing device to read at one time. According to the bluetooth protocol specification, an error between the local bluetooth time of the second audio playing device estimated by the first audio playing device and the actual local bluetooth time of the second audio playing device is not more than 1us, that is, an error between the audio synchronous playing time determined by the first audio playing device and the audio synchronous playing time determined by the second audio playing device is not more than 1 us. That is to say, the synchronous playing time determined by the first audio playing device is very close to the synchronous playing time determined by the second audio playing device, and the error is in the order of microseconds, so that the audio playing synchronization precision of the first audio playing device and the second audio playing device can be effectively improved.

In some optional embodiments, when the audio signal provided by the audio providing device is played synchronously with the second audio playing device based on the synchronous playing time, the first audio playing device sends an audio synchronous playing request to the second audio playing device based on the synchronous playing time, where the audio synchronous playing request is used to enable the second audio playing device to determine a playing start time and a playing period of the audio signal, and generate an audio synchronous playing response sent to the first audio playing device based on the playing start time and the playing period of the audio signal. Then, the first audio playing device receives the start playing time and the playing period of the audio signal carried in the audio synchronous playing response from the second audio playing device, and generates a periodic level signal or a periodic pulse signal for synchronously playing the audio signal. Finally, the first audio playing device synchronously plays the audio signal provided by the audio providing device with the second audio playing device based on the periodic level signal or the periodic pulse signal. Therefore, the synchronous audio playing of the first audio playing device and the second audio playing device can be effectively realized through the periodic level signal or the periodic pulse signal generated by the starting playing time and the playing period of the audio signal.

In a specific example, when the second audio playing device determines the start playing time and the playing period of the audio signal based on the audio synchronous playing request, the second audio playing device obtains the local bluetooth time of the second audio playing device based on the audio synchronous playing request; determining the synchronous playing time of the audio signals of the first audio playing device and the second audio playing device based on the local Bluetooth time of the second audio playing device; and determining the starting playing time and the playing period of the audio signal based on the local synchronous playing time.

In a specific example, as shown in fig. 1B, the first audio playing device is a bluetooth slave earphone, and the second audio playing device is a bluetooth master earphone. Specifically, when the status information of the bluetooth controller is information indicating that the bluetooth controller is in an operating state, the audio synchronization playing device of the bluetooth slave earphone determines that the bluetooth time currently sampled from the bluetooth controller is the local bluetooth time of the bluetooth slave earphone. And when the state information of the Bluetooth controller is information indicating that the Bluetooth controller is in a dormant state, the audio synchronous playing device of the Bluetooth slave earphone determines that the addition result of the low power consumption time collected from the low power consumption clock and the Bluetooth time sampled from the Bluetooth controller at the latest time at present is the local Bluetooth time of the Bluetooth slave earphone. After obtaining the local bluetooth time of the bluetooth slave earphone, the audio synchronous playing device of the bluetooth slave earphone obtains the offset time of the local bluetooth time of the bluetooth slave earphone relative to the local bluetooth time of the bluetooth master earphone from the firmware of the bluetooth controller, and adds the offset time with the local bluetooth time of the bluetooth slave earphone to obtain the estimated local bluetooth time of the bluetooth master earphone. After the estimated local Bluetooth time of the Bluetooth master earphone is obtained, the audio synchronous playing device of the Bluetooth slave earphone synchronously plays the audio signal provided by the mobile phone terminal with the Bluetooth master earphone based on the estimated local Bluetooth time of the Bluetooth master earphone.

In a specific example, as shown in fig. 1C, the first audio playing device is a bluetooth slave earphone, the second audio playing device is a bluetooth master earphone, and the audio providing device is a mobile phone terminal. The Bluetooth master earphone is connected with the mobile phone terminal through a Bluetooth link 1, and the Bluetooth master earphone is connected with the Bluetooth slave earphone through a Bluetooth link 2. The bluetooth master earphone is responsible for forwarding the audio signal sent by the mobile phone terminal to the bluetooth slave earphone, that is, the bluetooth master earphone and the bluetooth slave earphone are in a forwarding mode of a classic bluetooth protocol. The audio playing synchronization process of the bluetooth master earphone and the bluetooth slave earphone is similar to the audio playing synchronization process of the bluetooth master earphone and the bluetooth slave earphone described with reference to fig. 1B in this embodiment, and is not described herein again. According to the Bluetooth protocol specification, the error between the local Bluetooth time of the Bluetooth master earphone estimated by the Bluetooth slave earphone and the actual local Bluetooth time of the Bluetooth master earphone is not more than 1us, that is, the error between the audio synchronous playing time determined by the Bluetooth slave earphone and the audio synchronous playing time determined by the Bluetooth master earphone is not more than 1 us. If the mobile phone terminal sends one frame of audio signal every 10ms, and the clock precision of the bluetooth slave earphone is 20ppm (parts per million), the deviation of the synchronous playing time of the bluetooth master earphone and the bluetooth slave earphone does not exceed 10ms by 20ppm being 0.2 us. Therefore, in the forwarding mode of the classic bluetooth, the deviation of the audio synchronous playing method provided by the embodiment is in the microsecond level.

In this embodiment, the local bluetooth time of the second audio playing device is estimated by the local bluetooth time of the first audio playing device and the offset time of the local bluetooth time of the first audio playing device relative to the local bluetooth time of the second audio playing device, so that the first audio playing device can obtain the absolute time of the second audio playing device, and further, based on the estimated local bluetooth time of the second audio playing device, the audio signal provided by the audio providing device is played synchronously with the second audio playing device, and in addition, the local bluetooth time of the first audio playing device and the offset time of the local bluetooth time of the first audio playing device relative to the local bluetooth time of the second audio playing device are both obtained based on the bluetooth time of the bluetooth controller in the first audio playing device, and the inside of bluetooth controller possesses the clock that realizes accurate to the microsecond, consequently, can effectively improve the synchronous precision of audio playback of first audio playback equipment and second audio playback equipment, and need not additionally to occupy the antenna and carry out the receipt and the transmission of audio playback synchronization signal.

Referring to fig. 2A, a flowchart of an audio synchronous playing method in the second embodiment of the present application is shown.

The audio synchronous playing method provided by the embodiment can be applied to the listening mode of the classic bluetooth protocol. Before describing the audio synchronous playing method provided by the embodiment in detail, the listening mode of the classic bluetooth protocol is described in detail. Suppose that a communication system comprises an audio providing device, a first audio playing device connected with the audio providing device through Bluetooth, and a second audio playing device connected with the first audio playing device in communication, wherein the first audio playing device can transmit related communication parameters to the second audio playing device, such as: the Bluetooth system comprises bottom layer Bluetooth protocol parameters such as Bluetooth time, Bluetooth addresses, 3BIT logical addresses, frequency hopping sequences, connection keys and coding keys, upper layer Bluetooth protocol parameters such as L2CAP, RFCOMM, Handfree and A2DP and the like. And the second audio playing device enters the Bluetooth network between the audio providing device and the first audio playing device in a monitoring mode according to the related communication parameters, so as to complete networking. If the audio providing device sends an audio signal to the first audio playing device, the second audio playing device can also receive the audio signal sent by the audio providing device to the first audio playing device by monitoring the Bluetooth connection between the audio providing device and the first audio playing device.

The present embodiment describes the audio synchronous playing method provided by the present embodiment in detail from the perspective of the first audio playing device. Specifically, the audio synchronous playing method provided by this embodiment includes the following steps:

in step S201, state information of a bluetooth controller in the first audio playing device and bluetooth time of the bluetooth controller in the first audio playing device are obtained, and local bluetooth time of the first audio playing device is determined according to the state information and the bluetooth time obtained from the bluetooth controller in the first audio playing device.

Since the specific implementation of step S201 is similar to the specific implementation of step S101 in the first embodiment, it is not repeated herein.

In step S202, the local bluetooth time of the audio providing device is estimated based on the local bluetooth time of the first audio playing device and the offset time of the local bluetooth time of the first audio playing device relative to the local bluetooth time of the audio providing device, and the estimated local bluetooth time of the audio providing device is determined as the estimated absolute time.

In this embodiment, the second audio playing device is paired with the first audio playing device and connected to the audio providing device through bluetooth. For an example that the second audio playing device is paired with the first audio playing device and the audio providing device is connected to the first audio playing device through bluetooth, refer to step S102 in the first embodiment, which is not described herein again.

In a specific example, since the first audio playback device and the second audio playback device are in a listening mode of a classic bluetooth protocol, the first audio playback device includes a bluetooth master earphone or a bluetooth slave earphone, and the second audio playback device includes a bluetooth master earphone or a bluetooth slave earphone. The offset time of the local bluetooth time of the first audio playback device relative to the local bluetooth time of the audio providing device may be obtained from bluetooth controller firmware.

In a specific example, when estimating the local bluetooth time of the audio providing device, the local bluetooth time of the first audio playing device and an offset time of the local bluetooth time of the first audio playing device relative to the local bluetooth time of the audio providing device may be added to obtain the estimated local bluetooth time of the audio providing device.

In step S203, the audio signal provided by the audio providing device is played synchronously with the second audio playing device based on the estimated absolute time.

In some optional embodiments, when the audio signal provided by the audio providing device is played synchronously with the second audio playing device based on the estimated absolute time, performing a modulo operation on the estimated local bluetooth time of the audio providing device to obtain the synchronous playing time of the audio signals of the first audio playing device and the second audio playing device; and synchronously playing the audio signal provided by the audio providing equipment with the second audio playing equipment based on the synchronous playing time. Therefore, the synchronous playing time of the audio signals of the first audio playing device and the second audio playing device, which is obtained by performing the modulus operation on the estimated local Bluetooth time of the audio providing device, can be conveniently read by the audio playing module in the first audio playing device at one time.

In some optional embodiments, when the audio signal provided by the audio providing device is played synchronously with the second audio playing device based on the synchronous playing time, an audio synchronous playing request is sent to the second audio playing device based on the synchronous playing time, where the audio synchronous playing request is used for the second audio playing device to determine a starting playing time and a playing period of the audio signal, and to generate an audio synchronous playing response sent to the first audio playing device based on the starting playing time and the playing period of the audio signal; receiving the starting playing time and the playing period of the audio signal carried in the audio synchronous playing response from a second audio playing device, and generating a periodic level signal or a periodic pulse signal for synchronously playing the audio signals of the first audio playing device and the second audio playing device; and based on the periodic level signal or the periodic pulse signal, synchronously playing the audio signal provided by the audio providing equipment with the second audio playing equipment. Therefore, the synchronous audio playing of the first audio playing device and the second audio playing device can be effectively realized through the periodic level signal or the periodic pulse signal generated by the starting playing time and the playing period of the audio signal.

In a specific example, when the second audio playing device determines the start playing time and the playing period of the audio signal based on the audio synchronous playing request, the second audio playing device obtains the estimated local bluetooth time of the audio providing device based on the audio synchronous playing request; based on the estimated local Bluetooth time of the audio providing equipment, determining the synchronous playing time of the audio signals of the first audio playing equipment and the second audio playing equipment; and determining the starting playing time and the playing period of the audio signal based on the local synchronous playing time. The specific implementation of the second audio playing device for determining the local synchronous playing time is similar to the specific implementation of the first audio playing device for determining the local synchronous playing time, and the specific implementation of the local bluetooth time of the audio providing device is also similar to the prediction, the synchronous playing time determined by the second audio playing device is very close to the determined synchronous playing time, and the error is in the microsecond level, so that the audio playing synchronization precision of the first audio playing device and the second audio playing device can be effectively improved.

In a specific example, as shown in fig. 2B, the first audio playing device is a bluetooth slave earphone, the second audio playing device is a bluetooth master earphone, and the audio providing device is a mobile phone terminal. The Bluetooth master earphone is connected with the mobile phone terminal in a Bluetooth mode, and the Bluetooth master earphone is in communication connection with the Bluetooth slave earphone. The audio synchronous playing process of the Bluetooth master earphone and the Bluetooth slave earphone is as follows: and when the state information of the Bluetooth controller is information indicating that the Bluetooth controller is in a working state, the audio synchronous playing device of the Bluetooth slave earphone determines the Bluetooth time sampled from the Bluetooth controller as the local Bluetooth time of the Bluetooth slave earphone. And when the state information of the Bluetooth controller is information indicating that the Bluetooth controller is in a dormant state, the audio synchronous playing device of the Bluetooth slave earphone determines that the addition result of the low power consumption time sampled from the low power consumption clock and the Bluetooth time sampled from the Bluetooth controller at the latest time at present is the local Bluetooth time of the Bluetooth slave earphone. After the local Bluetooth time of the Bluetooth slave earphone is obtained, the audio synchronous playing device of the Bluetooth slave earphone obtains the offset time of the local Bluetooth time of the Bluetooth slave earphone relative to the local Bluetooth time of the mobile phone terminal from the Bluetooth controller firmware, and adds the offset time with the local Bluetooth time of the Bluetooth slave earphone to obtain the estimated local Bluetooth time of the mobile phone terminal. After the estimated local Bluetooth time of the mobile phone terminal is obtained, the Bluetooth slave earphone performs a modular operation on the estimated local Bluetooth time of the mobile phone terminal by using an audio synchronous playing device of the Bluetooth slave earphone so as to obtain the synchronous playing time of the audio signal. Similarly, the bluetooth master earpiece obtains a synchronized playback time of the audio signal in the same manner as the bluetooth slave earpiece. Then, the bluetooth slave earphone generates a periodic level signal or a periodic pulse signal for synchronously playing the audio signal based on the synchronous playing time, and finally, the bluetooth slave earphone synchronously plays the audio signal provided by the mobile phone terminal with the bluetooth master earphone based on the periodic level signal or the periodic pulse signal.

According to the Bluetooth protocol specification, the error between the local Bluetooth time of the mobile phone terminal estimated by the Bluetooth slave earphone and the actual local Bluetooth time of the mobile phone terminal does not exceed 1us, and the error between the local Bluetooth time of the mobile phone terminal estimated by the Bluetooth master earphone and the actual local Bluetooth time of the mobile phone terminal does not exceed 1us, so that the error between the local Bluetooth time of the mobile phone terminal estimated by the Bluetooth master earphone and the local Bluetooth time of the mobile phone terminal estimated by the Bluetooth slave earphone does not exceed 2 us. That is, the error between the synchronized playback time determined by the bluetooth slave earphone and the synchronized playback time determined by the bluetooth master earphone does not exceed 2 us. If the mobile phone terminal sends one frame of audio signal every 10ms, and the time accuracies of the bluetooth master earphone and the bluetooth slave earphone are both 20ppm (parts per million), the time deviation between the bluetooth master earphone or the bluetooth slave earphone and the mobile phone terminal is not more than 10ms × 20ppm — 0.2us, that is, the deviation of the synchronous playing time between the bluetooth master earphone and the bluetooth slave earphone is usually not more than 2.4 us. Therefore, in the listening mode of the classic bluetooth, the deviation of the audio synchronous playing method provided by the embodiment is in the microsecond level.

In this embodiment, the local bluetooth time of the audio providing device is estimated by the local bluetooth time of the first audio playing device and the offset time of the local bluetooth time of the first audio playing device relative to the local bluetooth time of the audio providing device, so that the first audio playing device obtains the absolute time of the audio providing device, and further, the audio signal provided by the audio providing device is played synchronously with the second audio playing device based on the estimated local bluetooth time of the audio providing device, and in addition, the local bluetooth time of the first audio playing device and the offset time of the local bluetooth time of the first audio playing device relative to the local bluetooth time of the audio providing device are both obtained based on the bluetooth time of the bluetooth controller in the first audio playing device, and the inside of the Bluetooth controller is provided with a clock accurate to microsecond, so that the audio synchronous playing precision of the first audio playing device and the second audio playing device can be effectively improved, and an antenna is not required to be additionally occupied for receiving and sending audio playing synchronous signals.

Referring to fig. 3A, a flowchart of an audio synchronous playing method in the third embodiment of the present application is shown.

The audio synchronous playing method provided by the embodiment can be applied to a synchronous mode of a low-power Bluetooth protocol. Before describing the audio synchronous playing method provided by the embodiment in detail, a synchronous mode of the bluetooth low energy protocol is described in detail. A Connected Isochronous Stream (CIS) in the synchronization mode of the bluetooth low energy protocol is a protocol that is newly proposed by the bluetooth low energy protocol and is suitable for connection-oriented multichannel synchronous data transceiving of a TWS bluetooth headset, as shown in fig. 3B, and its main features are as follows: within a synchronous time slot (e.g. 10ms), the master device (e.g. handset terminal) and the slave device (e.g. bluetooth master in TWS bluetooth headset) will complete the current data interaction, and the data interaction has real-time performance. Specifically, if the master device does not receive the acknowledgement message from the slave device after 150us, it will consider that the slave device has not received the data, and the master device will automatically retransmit the data. If the slave device does not receive the data within the specified time, a timeout will result and the master device will not retransmit the data that has timed out. And the parameters such as the synchronous time slot, the overtime information and the like are issued to the slave equipment by the master equipment. Furthermore, as shown in fig. 3C, the expected bluetooth data transmitted by the multiple isochronous connection stream communication links may be aligned, and the alignment point is a synchronization point (usually, the end time of the last isochronous connection stream communication link), that is, the bluetooth controller in the slave device in the multiple isochronous connection stream communication links uploads the received expected bluetooth data (e.g., audio signal) to the upper layer (e.g., audio playback module) of the slave device at the alignment point (at the same time). The waiting uploading time of the expected Bluetooth data received by the Bluetooth controllers in different slave devices is controlled by the synchronous delay parameter in the synchronous connection streaming communication link of each slave device, and the synchronous delay parameter is issued to the slave devices by the master device. Wherein the plurality of synchronous connection stream communication links form a synchronous connection string Group (CIG). In a specific application scenario, as shown in fig. 3D, a synchronous connection streaming communication link is respectively established between the mobile phone terminal and a bluetooth master earphone and between the mobile phone terminal and a bluetooth slave earphone in the TWS bluetooth earphone, where the synchronous connection streaming communication link established between the mobile phone terminal and the bluetooth master earphone is a synchronous connection streaming 1, and the synchronous connection streaming communication link established between the mobile phone terminal and the bluetooth slave earphone is a synchronous connection streaming 2. Meanwhile, the mobile phone terminal distributes time parameters of the synchronous connection stream 1 and the synchronous connection stream 2, such as a synchronous time slot, a data transmission delay, a synchronous delay (a time difference between the synchronous connection stream 1 and the synchronous connection stream 2 with respect to a synchronous point), and the like, to the bluetooth master earphone and the bluetooth slave earphone, respectively. After receiving the audio signals, the Bluetooth master earphone and the Bluetooth slave earphone synchronously send the received audio signals to the audio playing modules of the Bluetooth master earphone and the Bluetooth slave earphone according to respective time parameters. Then, the audio playing modules of the Bluetooth master earphone and the Bluetooth slave earphone respectively decode and play the received audio signals.

in step S301, state information of a bluetooth controller in the first audio playing device and bluetooth time of the bluetooth controller in the first audio playing device are obtained, and local bluetooth time of the first audio playing device is determined according to the state information and the bluetooth time obtained from the bluetooth controller in the first audio playing device.

In some optional embodiments, the first audio playback device is bluetooth connected with the audio providing device via a first isochronous connection streaming communication link, and the second audio playback device is bluetooth connected with the audio providing device via a second isochronous connection streaming communication link. When the local Bluetooth time of the first audio playing device is determined according to the state information and the Bluetooth time acquired from the Bluetooth controller in the first audio playing device, when the first synchronous connection streaming communication link is at the nth synchronous point, the local Bluetooth time of the first audio playing device is determined based on the state information of the Bluetooth controller in the first audio playing device and the Bluetooth time acquired from the Bluetooth controller in the first audio playing device, wherein n is an integer equal to or greater than 2. Therefore, the local Bluetooth time of the first audio playing device when the first synchronous connection streaming communication link is at the nth synchronous point can be accurately determined through the state information of the Bluetooth controller in the first audio playing device and the Bluetooth time acquired from the Bluetooth controller in the first audio playing device.

In a specific example, the first audio playing device may be a bluetooth master speaker, a bluetooth slave speaker, a bluetooth master earphone or a bluetooth slave earphone in a TWS bluetooth headset, or the like. The second audio playing device can be a Bluetooth master speaker, a Bluetooth slave speaker, a Bluetooth master earphone or a Bluetooth slave earphone in a TWS Bluetooth earphone, and the like. The synchronization point may be understood as a time point when the bluetooth controller in the first audio playing device accessing the first synchronization connection streaming communication link synchronously uploads the received audio signal to the audio playing module of the first audio playing device. The bluetooth controller may be understood as a chip that controls bluetooth communication or data transmission of the first audio playback device. The state information may be understood as information indicating a state in which the bluetooth controller is located, for example, information indicating that the bluetooth controller is in an operating state, information indicating that the bluetooth controller is in a sleep state, and the like. Since the specific implementation manner of determining the local bluetooth time of the first audio playing device according to the state information and the bluetooth time obtained from the bluetooth controller in the first audio playing device in this embodiment is similar to the specific implementation manner of step S101 in the first embodiment, details are not repeated here.

In step S302, an elapsed time of the first local bluetooth time with respect to the second local bluetooth time is determined based on a first local bluetooth time of the first audio playing device, a second local bluetooth time of the first audio playing device, and an offset time of the local bluetooth time of the first audio playing device with respect to a local bluetooth time of the audio providing device, and the elapsed time is determined as the estimated absolute time.

In this embodiment, the first local bluetooth time is a local bluetooth time of the first audio playing device when the first synchronization link is at an nth synchronization point, and the second local bluetooth time is a local bluetooth time of the first audio playing device when the first synchronization link is at a first synchronization point. The second audio playing device is paired with the first audio playing device and connected with the audio providing device through common Bluetooth. For an example that the second audio playing device is paired with the first audio playing device and the audio providing device is connected to the first audio playing device through bluetooth, refer to step S102 in the first embodiment, which is not described herein again.

In one specific example, since a master device (e.g., an audio providing device) does not transmit a local bluetooth time of the master device (e.g., an audio providing device) to a slave device (e.g., a first audio playing device) in the bluetooth low energy protocol specification, the first audio playing device cannot determine an absolute time of the audio providing device by estimating the local bluetooth time of the audio providing device. Therefore, the absolute time of the second audio playback device can be determined by using the synchronization characteristics of the first and second synchronization connection stream communication links, and taking the local bluetooth time of the first audio playback device when the first synchronization connection stream communication link is at the first synchronization point as the reference time, and taking the local bluetooth time of the second audio playback device when the second synchronization connection stream communication link is at the first synchronization point as the reference time. Furthermore, considering the frequency deviation of the bluetooth communication device, the bluetooth low energy protocol specification requires that the slave device in the bluetooth communication calculates the offset time of the local bluetooth time of the slave device relative to the local bluetooth time of the master device when receiving the expected bluetooth data, and performs calibration according to the calculated offset time to ensure that the time difference between the master device and the slave device does not exceed 1us at the synchronization point. Specifically, when the bluetooth controller of the first audio playing device receives the expected bluetooth data from the audio providing device each time, the expected arrival time of the expected bluetooth data may be accurately calculated according to the synchronization time slot, the event count parameter, and the like, and a difference between the expected arrival time of the expected bluetooth data and the actual arrival time of the expected bluetooth data may be calculated, and then the difference may be determined as an offset time of the local bluetooth time of the first audio playing relative to the local bluetooth time of the audio providing device.

In a specific example, when determining an elapsed time of a first local bluetooth time of the first audio playing device relative to a second local bluetooth time of the first audio playing device, the first local bluetooth time is subtracted by the second local bluetooth time to obtain a time subtraction result, and the time subtraction result is added to an offset time of the local bluetooth time of the first audio playing device relative to the local bluetooth time of the audio providing device to obtain the elapsed time of the first local bluetooth time of the first audio playing device relative to the second local bluetooth time of the first audio playing device.

In step S303, based on the estimated absolute time, the audio signal provided by the audio providing device is played synchronously with the second audio playing device.

In some optional embodiments, when the audio signal provided by the audio providing device is played synchronously with the second audio playing device based on the estimated absolute time, if the synchronization point at which the second sync link streaming communication link is located is aligned with the nth synchronization point at which the first sync link streaming communication link is located, the sync playing time of the audio signal of the first audio playing device and the second audio playing device is determined based on the elapsed time, and the audio signal provided by the audio providing device is played synchronously with the second audio playing device based on the sync playing time. Thereby, by the elapsed time, the synchronized playback time of the audio signals of the first audio playback device and the second audio playback device can be accurately determined.

In some optional embodiments, when determining the synchronized playing time of the audio signals of the first audio playing device and the second audio playing device based on the elapsed time, the synchronized playing time of the audio signals of the first audio playing device and the second audio playing device is determined based on the elapsed time and a preconfigured maximum audio decoding duration. Wherein the preconfigured maximum audio decoding duration may be 5 ms. Therefore, the synchronous playing time of the audio signals of the first audio playing device and the second audio playing device can be accurately determined through the elapsed time and the preset maximum audio decoding time.

In a specific example, the audio providing device is a mobile phone terminal, the first audio playing device is a bluetooth master earphone in a TWS bluetooth earphone, the second audio playing device is a bluetooth slave earphone in the TWS bluetooth earphone, and the bluetooth master earphone and the bluetooth slave earphone are bluetooth-connected to the mobile phone terminal through a first synchronous connection streaming communication link and a second synchronous connection streaming communication link, respectively. If the first isochronous link stream communication link is currently at the nth isochronous point and the m (m is an integer equal to or greater than 1) th isochronous point at which the second isochronous link stream communication link is currently located is aligned with the nth isochronous point at which the first isochronous link stream communication link is currently located, the bluetooth master may obtain an elapsed time of the local bluetooth time of the first isochronous link stream communication link at the nth isochronous point relative to the local bluetooth time of the first isochronous link stream communication link at the first isochronous point plus the preconfigured maximum audio decoding duration, and may obtain the synchronized playback time of the audio signals of the bluetooth master and the bluetooth slave locally to the bluetooth master, and similarly, the bluetooth slave may obtain the local bluetooth time of the second isochronous link stream communication link at the mth isochronous point relative to the second isochronous link stream communication link The elapsed time of the local Bluetooth time when the communication link is at the first synchronization point plus the preconfigured maximum audio decoding duration can obtain the synchronous playing time of the audio signals of the Bluetooth master earphone and the Bluetooth slave earphone local to the Bluetooth slave earphone. Since the mth synchronization point at which the second synchronous connection streaming communication link is currently located is aligned with the nth synchronization point at which the first synchronous connection streaming communication link is currently located, the time for the bluetooth slave earphone to upload the received audio signal to the audio playing module of the bluetooth slave earphone is the same as the time for the bluetooth master earphone to upload the received audio signal to the audio playing module of the bluetooth master earphone, and therefore, the decoding duration of the audio signal by the audio playing module of the bluetooth slave earphone and the decoding duration of the audio signal by the audio playing module of the bluetooth master earphone need only be considered. Because the audio signals received by the Bluetooth master earphone and the Bluetooth slave earphone are different, the decoding time of the audio playing module of the Bluetooth slave earphone on the audio signals is different from the decoding time of the audio playing module of the Bluetooth master earphone on the audio signals, therefore, the maximum audio decoding time can be configured in advance to obtain the synchronous playing time of the audio signals of the Bluetooth master earphone and the Bluetooth slave earphone local to the Bluetooth master earphone and the synchronous playing time of the audio signals of the Bluetooth master earphone and the Bluetooth slave earphone local to the Bluetooth slave earphone, thereby realizing the synchronous playing of the audio signals of the Bluetooth master earphone and the Bluetooth slave earphone. Wherein the duration may be a maximum decoding duration of the audio signal frame, e.g. 5 ms.

In some optional embodiments, when determining the synchronized playing time of the audio signals of the first audio playing device and the second audio playing device based on the elapsed time, determining the synchronized playing time of the audio signals of the first audio playing device and the second audio playing device based on the elapsed time and a received second event count parameter sent by the second audio playing device, wherein the second event count parameter is used for counting the number of the synchronized time slots of the second audio playing device accessing the second synchronized connection streaming communication link. Therefore, the synchronous playing time of the audio signals of the first audio playing device and the second audio playing device can be accurately determined through the elapsed time and the received second event counting parameter sent by the second audio playing device.

In a specific example, according to the bluetooth low energy protocol, when the second audio playback device establishes the second synchronous connection streaming communication link with the audio providing device, the second event count parameter of the second audio playback device is zero, and is incremented by one at each time interval of the synchronous time slot. That is, the second event count parameter is used to count the number of synchronization slots for the second audio playback device to access the second synchronous connection stream communication link. The second audio playing device may send the second event count parameter to the first audio playing device in a broadcast manner or a communication connection establishment manner.

In some optional embodiments, when determining the synchronous playing time of the audio signals of the first audio playing device and the second audio playing device based on the elapsed time and the received second event count parameter sent by the second audio playing device, based on the elapsed time, a first event count parameter of the first audio playback device, a second event count parameter of the second audio playback device, and the first audio playing device accesses the synchronous time slot of the first synchronous connection streaming communication link to determine the synchronous playing time of the audio signals of the first audio playing device and the second audio playing device, wherein the first event count parameter of the first audio playback device is configured to count the number of synchronization slots when the first audio playback device accesses the first synchronization connection streaming communication link. Therefore, the synchronous playing time of the audio signals of the first audio playing device and the second audio playing device can be accurately determined through the elapsed time, the first event counting parameter of the first audio playing device, the second event counting parameter of the second audio playing device and the synchronous time slot of the first audio playing device accessing the first synchronous connection streaming communication link.

In a specific example, when determining a synchronous playing time of audio signals of the first audio playing device and the second audio playing device based on the elapsed time, the first event count parameter of the first audio playing device, the second event count parameter of the second audio playing device, and a synchronization time slot of the first audio playing device accessing the first synchronous connection streaming communication link, the first event count parameter of the first audio playing device is subtracted from the second event count parameter of the second audio playing device to obtain a subtraction result; multiplying the subtraction result by the synchronous time slot to obtain a multiplication result; adding the multiplication result and the elapsed time of the first audio playing device to obtain the synchronous playing time of the audio signals of the first audio playing device and the second audio playing device.

In a specific example, the audio providing device is a mobile phone terminal, the first audio playing device is a bluetooth master earphone in a TWS bluetooth earphone, the second audio playing device is a bluetooth slave earphone in the TWS bluetooth earphone, the bluetooth master earphone is bluetooth connected to the mobile phone terminal through the first synchronous connection streaming communication link, and the bluetooth slave earphone is bluetooth connected to the mobile phone terminal through the second synchronous connection streaming communication link. Since the time when the bluetooth master earphone and the handset terminal access the first synchronous connection stream communication link is different from the time when the bluetooth slave earphone and the handset terminal access the second synchronous connection stream communication link, and after the bluetooth master earphone and the handset terminal access the first synchronous connection stream communication link and the bluetooth slave earphone and the handset terminal access the second synchronous connection stream communication link, the synchronization point where the first synchronous connection stream communication link is located is aligned with the synchronization point where the second synchronous connection stream communication link is located, in a case where the mth synchronization point where the second synchronous connection stream communication link is currently located is aligned with the nth synchronization point where the first synchronous connection stream communication link is currently located, a first difference between a first elapsed time and a second elapsed time is equal to a multiple of a time interval between two adjacent synchronization points, wherein the first elapsed time is an elapsed time of a local bluetooth time of the bluetooth slave headset when the second synchronous connection stream communication link is currently at an m-th synchronization point relative to a local bluetooth time of the bluetooth slave headset when the second synchronous connection stream communication link is at a first synchronization point, the second elapsed time is an elapsed time of a local bluetooth time of the bluetooth master headset when the first synchronous connection stream communication link is currently at an n-th synchronization point relative to a local bluetooth time of the bluetooth master headset when the first synchronous connection stream communication link is at a first synchronization point, and a time interval of two adjacent synchronization points is a multiple of a synchronization slot, the first difference value can be presumed to be equal to a multiple of a synchronization slot, and an event count parameter of the bluetooth slave headset is used to count synchronization slots of the bluetooth slave headset accessing the second synchronous connection stream communication link, the event counting parameter of the bluetooth master earphone is used for counting the synchronous time slot of the bluetooth master earphone accessing the first synchronous connection streaming communication link, so that a second difference value of the event counting parameter of the bluetooth slave earphone and the event counting parameter of the bluetooth master earphone can be obtained according to the characteristic of a synchronous mode of a low power consumption bluetooth protocol. Thereby, it is obtained that the first difference is equal to the product of the second difference and the synchronization time slot, and further it is obtained that the first elapsed time is equal to the second elapsed time plus the product of the second difference and the synchronization time slot. Therefore, for the bluetooth slave earphone, the synchronous playing time of the audio signals of the bluetooth master earphone and the bluetooth slave earphone can be determined according to the first elapsed time, and for the bluetooth master earphone, the event counting parameter of the bluetooth slave earphone transmitted by the bluetooth slave earphone can be received, the second difference value can be calculated according to the event counting parameter of the bluetooth slave earphone, the product of the second difference value and the synchronous time slot is calculated, the product of the second difference value and the synchronous time slot is added with the second elapsed time, and finally the synchronous playing time of the audio signals of the bluetooth master earphone and the bluetooth slave earphone is determined according to the addition result.

In some optional embodiments, the specific implementation manner of playing the audio signal provided by the audio providing device synchronously with the second audio playing device based on the synchronous playing time is similar to the specific implementation manner of playing the audio signal provided by the audio providing device synchronously with the second audio playing device based on the synchronous playing time in step S203 of the second embodiment, and is not repeated here.

In a specific example, when the second audio playing device determines the start playing time and the playing period of the audio signal based on the audio synchronous playing request, the second audio playing device obtains the elapsed time of the second audio playing device based on the audio synchronous playing request; determining the synchronous playing time of the audio signals of the first audio playing device and the second audio playing device which are local based on the elapsed time of the second audio playing device; and determining the starting playing time and the playing period of the audio signal based on the local synchronous playing time. Wherein the elapsed time of the second audio playing device is an elapsed time of a local bluetooth time of the second audio playing device when the second synchronous connection streaming communication link is currently at the mth synchronization point, relative to a local bluetooth time of the second audio playing device when the second synchronous connection streaming communication link is at the first synchronization point, when the mth synchronization point at which the second synchronous connection streaming communication link is currently at is aligned with the nth synchronization point at which the first synchronous connection streaming communication link is currently at.

In a specific example, as shown in fig. 3E, the audio providing device is a mobile phone terminal, the first audio playing device is a bluetooth master earphone in a TWS bluetooth earphone, the second audio playing device is a bluetooth slave earphone in the TWS bluetooth earphone, and the mobile phone terminal establishes a synchronous connection streaming communication link with the bluetooth master earphone and the bluetooth slave earphone respectively, where the synchronous connection streaming communication link established between the mobile phone terminal and the bluetooth master earphone is a synchronous connection streaming 1 communication link, and the synchronous connection streaming communication link established between the mobile phone terminal and the bluetooth slave earphone is a synchronous connection streaming 2 communication link. The audio playing synchronization process of the bluetooth master earphone and the bluetooth slave earphone is similar to the audio playing synchronization process of the bluetooth master earphone and the bluetooth slave earphone described for step S303 in this embodiment, and is not described herein again.

In a specific example, as shown in fig. 3F, the audio providing device is a mobile phone terminal, the first audio playing device is a bluetooth master earphone in a TWS bluetooth headset, the second audio playing device is a bluetooth slave earphone in the TWS bluetooth headset, and the bluetooth master earphone is bluetooth connected to the mobile phone terminal through the first synchronous connection streaming communication link, and the bluetooth slave earphone is bluetooth connected to the mobile phone terminal through the second synchronous connection streaming communication link. If the second synchronous connection stream communication link is currently located at the mth synchronous point and the first synchronous connection stream communication link is currently located at the nth synchronous point, for the bluetooth slave earphone, the synchronous playing time of the audio signals of the bluetooth master earphone and the bluetooth slave earphone can be determined according to the first elapsed time, and for the bluetooth master earphone, the event counting parameter of the bluetooth slave earphone sent by the bluetooth slave earphone can be received, and the synchronous playing time can be determined according to the event counting parameter of the bluetooth slave earphone and the second elapsed time. Wherein the first elapsed time is an elapsed time of a local Bluetooth time of the Bluetooth slave headset when the second synchronous connection stream communication link is currently at the mth synchronization point relative to a local Bluetooth time of the Bluetooth slave headset when the second synchronous connection stream communication link is at the first synchronization point, and the second elapsed time is an elapsed time of a local Bluetooth time of the Bluetooth master headset when the first synchronous connection stream communication link is currently at the nth synchronization point relative to a local Bluetooth time of the Bluetooth master headset when the first synchronous connection stream communication link is at the first synchronization point. After the synchronous playing time is obtained, the Bluetooth master earphone and the Bluetooth slave earphone both generate a periodic level signal or a periodic pulse signal for synchronously playing the audio signals of the Bluetooth master earphone and the Bluetooth slave earphone based on the determined synchronous playing time, and synchronously play the audio signals based on the periodic level signal or the periodic pulse signal.

In this embodiment, by determining the elapsed time of the local bluetooth time of the first audio playing device when the first synchronous connection streaming communication link is at the nth synchronous point relative to the local bluetooth time of the first audio playing device when the first synchronous connection streaming communication link is at the first synchronous point, the first audio playing device can obtain the absolute time of the second audio playing device by using the synchronous characteristic of the synchronous connection streaming communication link, and then determine the synchronous playing time of the audio signals of the first audio playing device and the second audio playing device based on the absolute time of the second audio playing device, in addition, the local bluetooth time of the first synchronous connection streaming communication link at the nth synchronous point and the local bluetooth time of the first synchronous connection streaming communication link at the first synchronous point are both based on the bluetooth controller in the first audio playing device The Bluetooth time is obtained, and the inside of the Bluetooth controller is provided with a clock accurate to microsecond, so that the audio playing synchronization precision of the first audio playing device and the second audio playing device can be effectively improved, and an antenna is not required to be additionally occupied for receiving and sending audio playing synchronization signals.

The fourth embodiment of the present application provides an audio synchronous playing device, the device includes: the device comprises a timer in communication connection with a Bluetooth controller and a first audio playing module in communication connection with the timer, wherein the timer is used for determining the local Bluetooth time of the first audio playing module based on state information of the Bluetooth controller and the Bluetooth time acquired from the Bluetooth controller, the state information is information used for indicating the state of the Bluetooth controller, and the absolute time of a second audio playing module is estimated based on the local Bluetooth time of the first audio playing module and the offset time of the local Bluetooth time of the first audio playing module relative to the local Bluetooth time of the second audio playing module; or estimating the absolute time of the audio providing device based on the local bluetooth time of the first audio playing module and the offset time of the local bluetooth time of the first audio playing module relative to the local bluetooth time of the audio providing device, wherein the first audio playing module and the second audio playing module share the same bluetooth to connect the audio providing device; the first audio playing module is configured to play the audio signal provided by the audio providing device synchronously with the second audio playing module based on the estimated absolute time. Wherein the device further comprises the Bluetooth controller in communication connection with the timer. Therefore, the absolute time of the second audio playing module or the audio providing equipment is estimated by the timer according to the local Bluetooth time of the first audio playing module, so that the first audio playing module can obtain the absolute time of the second audio playing module or the audio providing equipment, and further enabling the first audio playing module to play the audio signal provided by the audio providing device synchronously with the second audio playing module based on the estimated absolute time, and furthermore, the local bluetooth time of the first audio playback module is derived based on the bluetooth time of the bluetooth controller, and the inside of bluetooth controller possesses the clock that realizes accurate to the microsecond, consequently, can effectively improve the audio frequency synchronous broadcast's of first audio playback module and second audio playback module precision to need not additionally to occupy the antenna and carry out the receipt and the transmission of audio frequency broadcast synchronizing signal.

In a specific example, as shown in fig. 4, the audio playing device where the first audio playing module is located is connected with the audio playing device where the second audio playing module is located through bluetooth. And an audio synchronous playing device is arranged in the audio playing equipment. The audio synchronous playing device comprises a Bluetooth controller, a timer in communication connection with the Bluetooth controller, and a first audio playing module in communication connection with the timer. And when the state information of the Bluetooth controller is the information indicating that the Bluetooth controller is in the working state, the timer determines that the Bluetooth time sampled from the Bluetooth controller is the local Bluetooth time of the first audio playing module. When the state information of the Bluetooth controller is information indicating that the Bluetooth controller is in a dormant state, the timer determines that the addition result of the low power consumption time sampled from the low power consumption clock and the Bluetooth time sampled from the Bluetooth controller at the current latest time is the local Bluetooth time of the first audio playing module. After the local Bluetooth time of the first audio playing module is obtained, the timer obtains the offset time of the local Bluetooth time of the first audio playing module relative to the local Bluetooth time of the second audio playing module from Bluetooth controller firmware, adds the offset time and the local Bluetooth time of the first audio playing module, and estimates the local Bluetooth time of the second audio playing module. After the local Bluetooth time of the second audio playing module is estimated, the timer determines that the estimated absolute time of the second audio playing module is the estimated local Bluetooth time of the second audio playing module, and sends the estimated local Bluetooth time of the second audio playing module to the first audio playing module. The first audio playing module performs a modulus operation on the estimated local Bluetooth time of the second audio playing module to obtain the synchronous playing time of the audio signals of the first audio playing module and the second audio playing module, generates a periodic level signal or a periodic pulse signal for synchronously playing the audio signals of the first audio playing module and the second audio playing module based on the synchronous playing time, and finally synchronously plays the audio signals provided by the audio providing equipment with the second audio playing module based on the periodic level signal or the periodic pulse signal.

An embodiment of the present application provides an audio synchronous playing device, the device includes: the device comprises a timer in communication connection with a Bluetooth controller and a first audio playing module in communication connection with the timer, wherein the timer is used for determining local Bluetooth time of the first audio playing module based on state information of the Bluetooth controller and Bluetooth time acquired from the Bluetooth controller, the state information is information used for indicating the state of the Bluetooth controller, absolute time of a second audio playing module is estimated based on the local Bluetooth time of the first audio playing module and offset time of the local Bluetooth time of the first audio playing module relative to the local Bluetooth time of the second audio playing module, and an audio playing synchronization signal is generated based on the estimated absolute time; or the audio playing synchronization signal is generated based on the estimated absolute time and the local bluetooth time of the first audio playing module and the offset time of the local bluetooth time of the first audio playing module relative to the local bluetooth time of the audio providing device, wherein the first audio playing module and the second audio playing module share the same bluetooth to connect the audio providing device; the first audio playing module is configured to play the audio signal provided by the audio providing device synchronously with the second audio playing module based on the audio playing synchronization signal. The audio playing synchronization signal can be a periodic level signal or a periodic pulse signal, and the device further comprises the Bluetooth controller in communication connection with the timer. Therefore, the timer can predict the absolute time of the second audio playing module or the audio providing equipment according to the local Bluetooth time of the first audio playing module, so that the timer can obtain the audio playing synchronous signals of the first audio playing module and the second audio playing module based on the absolute time, and further enable the first audio playing module to play the audio signal provided by the audio providing device synchronously with the second audio playing module based on the audio playing synchronization signal, and furthermore, the local bluetooth time of the first audio playback module is derived based on the bluetooth time of the bluetooth controller, and the inside of bluetooth controller possesses the clock that realizes accurate to the microsecond, consequently, can effectively improve the audio frequency synchronous broadcast's of first audio playback module and second audio playback module precision to need not additionally to occupy the antenna and carry out the receipt and the transmission of audio frequency broadcast synchronizing signal.

In a specific example, as shown in fig. 5, the audio playing device where the first audio playing module is located is connected with the audio playing device where the second audio playing module is located through bluetooth. Different from the flow shown in fig. 4, the timer does not send the estimated local bluetooth time of the second audio playing module to the first audio playing module, but performs a module extraction operation on the estimated local bluetooth time of the second audio playing module to obtain the synchronous playing time of the audio signals of the first audio playing module and the second audio playing module, generates a periodic level signal or a periodic pulse signal for synchronously playing the audio signals of the first audio playing module and the second audio playing module based on the synchronous playing time, and finally sends the periodic level signal or the periodic pulse signal to the first audio playing module. The first audio playing module and the second audio playing module synchronously play the audio signals provided by the audio providing equipment based on the periodic level signals or the periodic pulse signals.

Based on the audio synchronous playing method described in the foregoing embodiment, a sixth embodiment of the present application provides an electronic device, configured to execute the audio synchronous playing method described in the foregoing embodiment, as shown in fig. 6, where the electronic device 600 includes: at least one processor (processor)602, memory (memory)604, bus 606, and communication Interface (communication Interface) 608.

Wherein:

the processor 602, communication interface 608, and memory 604 communicate with one another via a communication bus 606.

A communication interface 608 for communicating with other devices.

The processor 602 is configured to execute the program 610, and may specifically perform relevant steps in the audio synchronous playing method described in the first to third embodiments.

In particular, program 610 may include program code comprising computer operating instructions.

The processor 602 may be a central processing unit CPU, or an application Specific Integrated circuit asic, or one or more Integrated circuits configured to implement embodiments of the present application. The electronic device comprises one or more processors, which can be the same type of processor, such as one or more CPUs; or may be different types of processors such as one or more CPUs and one or more ASICs.

And a memory 604 for storing a program 610. Memory 604 may comprise high-speed RAM memory and may also include non-volatile memory (non-volatile memory), such as at least one disk memory.

Based on the audio synchronous playing method described in the first to third embodiments, an embodiment of the present application provides a computer-readable storage medium, on which a computer program is stored, and the computer program, when executed by a processor, implements the audio synchronous playing method described in the first to third embodiments.

The computing device and the electronic apparatus of the embodiments of the present application exist in various forms, including but not limited to:

(1) a mobile communication device: such devices are characterized by mobile communications capabilities and are primarily targeted at providing voice, data communications. Such terminals include: smart phones (e.g., iphones), multimedia phones, functional phones, and low-end phones, among others.

(2) Ultra mobile personal computer device: the equipment belongs to the category of personal computers, has calculation and processing functions and generally has the characteristic of mobile internet access. Such terminals include: PDA, MID, and UMPC devices, etc., such as ipads.

(3) A portable entertainment device: such devices can display and play multimedia content. This type of device comprises: audio, video players (e.g., ipods), handheld game consoles, electronic books, and smart toys and portable car navigation devices.

(4) And other electronic equipment with data interaction function.

Thus, particular embodiments of the present subject matter have been described. Other embodiments are within the scope of the following claims. In some cases, the actions recited in the claims can be performed in a different order and still achieve desirable results. In addition, the processes depicted in the accompanying figures do not necessarily require the particular order shown, or sequential order, to achieve desirable results. In some embodiments, multitasking and parallel processing may be advantageous.

The controller may be implemented in any suitable manner, for example, the controller may take the form of, for example, a microprocessor or processor and a computer-readable medium storing computer-readable program code (e.g., software or firmware) executable by the (micro) processor, logic gates, switches, an Application Specific Integrated Circuit (ASIC), a programmable logic controller, and an embedded microcontroller, examples of which include, but are not limited to, the following microcontrollers: ARC 625D, Atmel AT91SAM, Microchip PIC18F26K20, and Silicone Labs C8051F320, the memory controller may also be implemented as part of the control logic for the memory. Those skilled in the art will also appreciate that, in addition to implementing the controller as pure computer readable program code, the same functionality can be implemented by logically programming method steps such that the controller is in the form of logic gates, switches, application specific integrated circuits, programmable logic controllers, embedded microcontrollers and the like. Such a controller may thus be considered a hardware component, and the means included therein for performing the various functions may also be considered as a structure within the hardware component. Or even means for performing the functions may be regarded as being both a software module for performing the method and a structure within a hardware component.

The systems, devices, modules or units illustrated in the above embodiments may be implemented by a computer chip or an entity, or by a product with certain functions. One typical implementation device is a computer. In particular, the computer may be, for example, a personal computer, a laptop computer, a cellular telephone, a camera phone, a smartphone, a personal digital assistant, a media player, a navigation device, an email device, a game console, a tablet computer, a wearable device, or a combination of any of these devices.

For convenience of description, the above devices are described as being divided into various units by function, and are described separately. Of course, the functionality of the units may be implemented in one or more software and/or hardware when implementing the present application.

As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

In a typical configuration, a computing device includes one or more processors (CPUs), input/output interfaces, network interfaces, and memory.

The memory may include forms of volatile memory in a computer readable medium, Random Access Memory (RAM) and/or non-volatile memory, such as Read Only Memory (ROM) or flash memory (flash RAM). Memory is an example of a computer-readable medium.

Computer-readable media, including both non-transitory and non-transitory, removable and non-removable media, may implement information storage by any method or technology. The information may be computer readable instructions, data structures, modules of a program, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), Static Random Access Memory (SRAM), Dynamic Random Access Memory (DRAM), other types of Random Access Memory (RAM), Read Only Memory (ROM), Electrically Erasable Programmable Read Only Memory (EEPROM), flash memory or other memory technology, compact disc read only memory (CD-ROM), Digital Versatile Discs (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices, or any other non-transmission medium that can be used to store information that can be accessed by a computing device. As defined herein, a computer readable medium does not include a transitory computer readable medium such as a modulated data signal and a carrier wave.

It should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

The application may be described in the general context of computer-executable instructions, such as program modules, being executed by a computer. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular transactions or implement particular abstract data types. The application may also be practiced in distributed computing environments where transactions are performed by remote processing devices that are linked through a communications network. In a distributed computing environment, program modules may be located in both local and remote computer storage media including memory storage devices.

The embodiments in the present specification are described in a progressive manner, and the same and similar parts among the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments. In particular, for the system embodiment, since it is substantially similar to the method embodiment, the description is simple, and for the relevant points, reference may be made to the partial description of the method embodiment.

The above description is only an example of the present application and is not intended to limit the present application. Various modifications and changes may occur to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. An audio synchronous playing method is applied to a first audio playing device, and comprises the following steps:

acquiring state information of a Bluetooth controller in the first audio playing device and Bluetooth time of the Bluetooth controller in the first audio playing device, and determining local Bluetooth time of the first audio playing device according to the state information and the Bluetooth time acquired from the Bluetooth controller in the first audio playing device, wherein the state information is information for indicating the state of the Bluetooth controller in the first audio playing device;

estimating the absolute time of a second audio playing device based on the local Bluetooth time of the first audio playing device and the offset time of the local Bluetooth time of the first audio playing device relative to the local Bluetooth time of the second audio playing device, and synchronously playing an audio signal provided by an audio providing device with the second audio playing device based on the estimated absolute time; or

Estimating the absolute time of the audio providing equipment based on the local Bluetooth time of the first audio playing equipment and the offset time of the local Bluetooth time of the first audio playing equipment relative to the local Bluetooth time of the audio providing equipment, and synchronously playing the audio signal provided by the audio providing equipment with the second audio playing equipment based on the estimated absolute time;

the second audio playing device is paired with the first audio playing device and connected with the audio providing device through common Bluetooth.

2. The method of claim 1, wherein the determining the local bluetooth time of the first audio playback device according to the status information and the bluetooth time obtained from the bluetooth controller in the first audio playback device comprises:

if the state information is information indicating that the Bluetooth controller is in a working state, determining that the local Bluetooth time of the first audio playing device is the Bluetooth time sampled from the Bluetooth controller;

and if the state information is information indicating that the Bluetooth controller is in a dormant state, determining local Bluetooth time of the first audio playing device based on the low power consumption time of the first audio playing device and the Bluetooth time sampled from the Bluetooth controller at the latest time, wherein the low power consumption time is the duration of the Bluetooth controller in the dormant state.

3. The method of claim 1, wherein the first audio playback device and the second audio playback device are in a forwarding mode of a classic Bluetooth protocol,

the estimating the absolute time of the second audio playing device based on the local bluetooth time of the first audio playing device and the offset time of the local bluetooth time of the first audio playing device relative to the local bluetooth time of the second audio playing device includes:

estimating the local Bluetooth time of the second audio playing device based on the local Bluetooth time of the first audio playing device and the offset time of the local Bluetooth time of the first audio playing device relative to the local Bluetooth time of the second audio playing device, and determining the estimated local Bluetooth time of the second audio playing device as the estimated absolute time.

4. The method of claim 3, wherein the playing the audio signal provided by the audio providing device synchronously with the second audio playing device based on the estimated absolute time comprises:

performing a modulus operation on the estimated local Bluetooth time of the second audio playing device to obtain the synchronous playing time of the audio signals of the first audio playing device and the second audio playing device;

and synchronously playing the audio signal provided by the audio providing equipment with the second audio playing equipment based on the synchronous playing time.

5. The method of claim 4, wherein the playing the audio signal provided by the audio providing device synchronously with the second audio playing device based on the synchronized playing time comprises:

based on the synchronous playing time, sending an audio synchronous playing request to the second audio playing device, where the audio synchronous playing request is used for enabling the second audio playing device to determine the starting playing time and the playing period of the audio signal, and based on the starting playing time and the playing period of the audio signal, generating an audio synchronous playing response sent to the first audio playing device;

receiving the starting playing time and the playing period of the audio signal carried in the audio synchronous playing response from a second audio playing device, and generating a periodic level signal or a periodic pulse signal for synchronously playing the audio signals of the first audio playing device and the second audio playing device;

and based on the periodic level signal or the periodic pulse signal, synchronously playing the audio signal provided by the audio providing equipment with the second audio playing equipment.

6. The method of claim 3, wherein said predicting the local Bluetooth time of the second audio playback device is preceded by:

determining an expected arrival time of the expected Bluetooth data from the second audio playing device to the first audio playing device;

determining a difference between the expected arrival time and an actual arrival time of the expected Bluetooth data from the second audio playing device to the first audio playing device;

and determining the difference value as the offset time of the local Bluetooth time of the first audio playing device relative to the local Bluetooth time of the second audio playing device.

7. The method of any of claims 3-6, wherein the first audio playback device is a Bluetooth slave and/or the second audio playback device is a Bluetooth master.

8. The method of claim 1, wherein the first audio playback device and the second audio playback device are in a listening mode of a classic Bluetooth protocol,

the estimating the absolute time of the audio providing device based on the local bluetooth time of the first audio playing device and the offset time of the local bluetooth time of the first audio playing device relative to the local bluetooth time of the audio providing device includes:

estimating the local Bluetooth time of the audio providing equipment based on the local Bluetooth time of the first audio playing equipment and the offset time of the local Bluetooth time of the first audio playing equipment relative to the local Bluetooth time of the audio providing equipment, and determining the estimated local Bluetooth time of the audio providing equipment as the estimated absolute time.

9. The method of claim 8, wherein the playing the audio signal provided by the audio providing device synchronously with the second audio playing device based on the estimated absolute time comprises:

performing a modulus operation on the estimated local Bluetooth time of the audio providing equipment to obtain the synchronous playing time of the audio signals of the first audio playing equipment and the second audio playing equipment;

10. The method of claim 9, wherein said playing the audio signal provided by the audio providing device synchronously with the second audio playing device based on the synchronized playing time comprises:

11. The method according to any one of claims 8 to 10, wherein the first audio playback device and the second audio playback device are both bluetooth headsets and/or the audio providing device is a mobile phone terminal.

12. The method of claim 1, wherein the first audio playback device is Bluetooth connected with the audio providing device via a first synchronous connection streaming communication link and the second audio playback device is Bluetooth connected with the audio providing device via a second synchronous connection streaming communication link,

the determining the local bluetooth time of the first audio playing device according to the state information and the bluetooth time acquired from the bluetooth controller in the first audio playing device includes:

when the first synchronous connection streaming communication link is at an nth synchronous point, determining the local Bluetooth time of the first audio playing device based on the state information of the Bluetooth controller in the first audio playing device and the Bluetooth time acquired from the Bluetooth controller in the first audio playing device, wherein n is an integer equal to or greater than 2.

13. The method of claim 12, wherein the estimating the absolute time of the audio providing device based on the local bluetooth time of the first audio playback device and an offset time of the local bluetooth time of the first audio playback device relative to the local bluetooth time of the audio providing device comprises:

determining an elapsed time of the first local bluetooth time relative to the second local bluetooth time based on a first local bluetooth time of the first audio playing device, a second local bluetooth time of the first audio playing device, and an offset time of the local bluetooth time of the first audio playing device relative to a local bluetooth time of the audio providing device, and determining the elapsed time as the estimated absolute time, wherein the first local bluetooth time is the local bluetooth time of the first audio playing device when the first synchronization connection stream communication link is at the nth synchronization point, and the second local bluetooth time is the local bluetooth time of the first audio playing device when the first synchronization connection stream communication link is at the first synchronization point.

14. The method of claim 13, wherein the playing the audio signal provided by the audio providing device synchronously with the second audio playing device based on the estimated absolute time comprises:

if the synchronization point of the second synchronous connection streaming communication link is aligned with the nth synchronization point of the first synchronous connection streaming communication link, determining the synchronous playing time of the audio signals of the first audio playing device and the second audio playing device based on the elapsed time, and synchronously playing the audio signals provided by the audio providing device with the second audio playing device based on the synchronous playing time.

15. The method of claim 14, wherein said determining a synchronized playback time of audio signals of the first audio playback device and the second audio playback device based on the elapsed time comprises:

and determining the synchronous playing time of the audio signals of the first audio playing device and the second audio playing device based on the elapsed time and the preset maximum audio decoding time.

16. The method of claim 14, wherein said determining a synchronized playback time of audio signals of the first audio playback device and the second audio playback device based on the elapsed time comprises:

and determining the synchronous playing time of the audio signals of the first audio playing device and the second audio playing device based on the elapsed time and a received second event counting parameter sent by the second audio playing device, wherein the second event counting parameter is used for counting the number of synchronous time slots of the second audio playing device accessing the second synchronous connection streaming communication link.

17. The method of claim 16, wherein the determining a synchronized playback time of audio signals of the first audio playback device and the second audio playback device based on the elapsed time and the received second event count parameter transmitted by the second audio playback device comprises:

determining the synchronous playing time of the audio signals of the first audio playing device and the second audio playing device based on the elapsed time, a first event counting parameter of the first audio playing device, a second event counting parameter of the second audio playing device, and a synchronous time slot of the first audio playing device accessing the first synchronous connection streaming communication link, wherein the first event counting parameter is used for counting the number of the synchronous time slots of the first audio playing device accessing the first synchronous connection streaming communication link.

18. An audio synchronized playback device, the device comprising:

a timer in communication connection with the Bluetooth controller, and a first audio playing module in communication connection with the timer,

the timer is used for determining the local Bluetooth time of the first audio playing module based on the state information of the Bluetooth controller and the Bluetooth time acquired from the Bluetooth controller, wherein the state information is used for indicating the state of the Bluetooth controller, and the absolute time of the second audio playing module is estimated based on the local Bluetooth time of the first audio playing module and the offset time of the local Bluetooth time of the first audio playing module relative to the local Bluetooth time of the second audio playing module; or estimating the absolute time of the audio providing device based on the local bluetooth time of the first audio playing module and the offset time of the local bluetooth time of the first audio playing module relative to the local bluetooth time of the audio providing device, wherein the first audio playing module and the second audio playing module share the same bluetooth to connect the audio providing device;

the first audio playing module is configured to play the audio signal provided by the audio providing device synchronously with the second audio playing module based on the estimated absolute time.

19. The apparatus of claim 18, wherein the apparatus further comprises the bluetooth controller in communicative connection with the timer.

20. An audio synchronized playback device, the device comprising:

the timer is used for determining the local Bluetooth time of the first audio playing module based on the state information of the Bluetooth controller and the Bluetooth time acquired from the Bluetooth controller, wherein the state information is used for indicating the state of the Bluetooth controller, estimating the absolute time of the second audio playing module based on the local Bluetooth time of the first audio playing module and the offset time of the local Bluetooth time of the first audio playing module relative to the local Bluetooth time of the second audio playing module, and generating an audio playing synchronization signal based on the estimated absolute time; or the audio playing synchronization signal is generated based on the estimated absolute time and the local bluetooth time of the first audio playing module and the offset time of the local bluetooth time of the first audio playing module relative to the local bluetooth time of the audio providing device, wherein the first audio playing module and the second audio playing module share the same bluetooth to connect the audio providing device;

the first audio playing module is configured to play the audio signal provided by the audio providing device synchronously with the second audio playing module based on the audio playing synchronization signal.

21. The apparatus of claim 20, wherein the apparatus further comprises the bluetooth controller in communicative connection with the timer.

22. A computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, implements the audio synchronized playback method as claimed in any one of claims 1 to 17.

23. An electronic device comprising the audio synchronous playback apparatus of claim 18 or 20.