CN104320843B - Audio synchronization method of Bluetooth sound production device - Google Patents

Abstract

An audio synchronization method for a Bluetooth sound device, wherein the Bluetooth sound device includes a first Bluetooth sound device and a second Bluetooth sound device, and the first Bluetooth sound device and the second Bluetooth sound device are connected and transmit digital audio packets via Bluetooth. The audio synchronization method described in the present invention includes the following steps: capturing the number of samples converted by the first Bluetooth sound device and the second Bluetooth sound device at a first time point; and adjusting the sample rate converted by the second Bluetooth sound device according to the number of samples converted by the first Bluetooth sound device and the second Bluetooth sound device. Through the audio synchronization method described in the present invention, the number of samples converted by multiple Bluetooth sound devices can be detected and adjusted regularly, so that the multiple Bluetooth sound devices can be kept in a synchronized state at all times.

Description

Audio synchronization method of bluetooth sounding device

technical field

The invention relates to an audio synchronization method of a bluetooth sounding device, which can regularly detect and adjust a plurality of bluetooth sounding devices, so that the plurality of bluetooth sounding devices are kept in a synchronized state at any time.

Background technique

Bluetooth (bluetooth) is a common wireless transmission technology, which is widely used in short-distance data transmission. During data transmission through Bluetooth, one of the two electronic devices can be defined as a master device (Master), and the other electronic device can be defined as a slave device (Slave). The master device and the slave device are paired, and personal area networks are constructed, so that the master device and the slave device can transmit data wirelessly. Generally speaking, the master device can be a mobile phone, and the slave device is a Bluetooth headset or speaker. The mobile phone can transmit digital sound data to the Bluetooth headset or speaker through Bluetooth for playback, and the Bluetooth headset can also transmit digital sound data to the mobile phone. .

SUMMARY OF THE INVENTION

The main purpose of the present invention is to provide an audio synchronization method of a Bluetooth sounding device, which can detect and adjust a plurality of Bluetooth sounding devices regularly, so that the plurality of Bluetooth sounding devices are kept in a synchronized state at any time.

The present invention provides an audio synchronization method of a Bluetooth sounding device, wherein one Bluetooth sounding device among a plurality of Bluetooth sounding devices transmits digital audio packets to other Bluetooth sounding devices through Bluetooth. The sample counts (sample count) converted by each Bluetooth sounding device are captured and compared at the same time point, so as to know whether each Bluetooth sounding device is synchronized.

The present invention provides an audio synchronization method of a Bluetooth sounding device, wherein one Bluetooth sounding device among a plurality of Bluetooth sounding devices transmits digital audio packets to other Bluetooth sounding devices through Bluetooth. Capture and compare the sample counts converted by each Bluetooth sound device at the same time point, and adjust the rate at which at least one Bluetooth sound device converts samples according to the respective sample counts, for example, adjust the rate at which the Bluetooth sound device of the slave device converts the samples , so that each Bluetooth sounding device can be synchronized.

The present invention provides an audio synchronization method of a Bluetooth sounding device, wherein one Bluetooth sounding device among a plurality of Bluetooth sounding devices transmits digital audio packets to other Bluetooth sounding devices through Bluetooth. Corresponding sequence numbers are mainly added to a plurality of digital audio packets, and the sequence numbers are used to represent the number of samples accumulated before each packet, so as to avoid errors in the process of retrieving the number of samples.

In order to achieve the above object, the present invention provides an audio synchronization method of a Bluetooth sounding device, wherein the Bluetooth sounding device includes a first Bluetooth sounding device and a second Bluetooth sounding device, and the first Bluetooth sounding device and the second Bluetooth sounding device are connected through Bluetooth and transmitting digital audio packets, including the following steps: retrieving the number of samples converted by the first bluetooth sounding device and the second bluetooth sounding device at a first time point; and according to the samples converted by the first bluetooth sounding device and the second bluetooth sounding device Quantity, adjusts the rate at which the second Bluetooth sounding device converts samples.

The present invention provides another audio synchronization method of a bluetooth sounding device, wherein the bluetooth sounding device comprises a first bluetooth sounding device and a second bluetooth sounding device, and the first bluetooth sounding device and the second bluetooth sounding device are connected through bluetooth and transmit digital audio packet, and includes the following steps: retrieving the number of samples converted by the first bluetooth sounding device at a first time point, and generating a first number of samples; transmitting the first time point and the first number of samples from the first bluetooth sounding device to the second bluetooth sounding device; acquiring the number of samples converted by the second bluetooth sounding device at the first time point, and generating a second number of samples; and adjusting the second bluetooth sounding device according to the first number of samples and the second number of samples The rate at which samples are converted.

In an embodiment of the audio synchronization method of the present invention, the method includes the following steps: comparing the number of samples converted by the first bluetooth sounding device and the second bluetooth sounding device at a first time point.

In an embodiment of the audio synchronization method of the present invention, the first Bluetooth sounding device is a master device, and the second Bluetooth sounding device is a slave device.

In an embodiment of the audio synchronization method of the present invention, the method includes the following method: capturing the number of samples converted by the first Bluetooth sounding device and the second Bluetooth sounding device at the same time point.

In an embodiment of the audio synchronization method of the present invention, the method includes the following steps: synchronizing the clocks of the first bluetooth sounding device and the second bluetooth sounding device.

An embodiment of the audio synchronization method of the present invention includes the following steps: pairing the first Bluetooth sounding device with the second Bluetooth sounding device, so that the first Bluetooth sounding device and the second Bluetooth sounding device use the same clock.

In an embodiment of the audio synchronization method of the present invention, the method includes the following steps: the first Bluetooth sounding device and the second Bluetooth sounding device define a first time point through a clock.

In an embodiment of the audio synchronization method of the present invention, the first bluetooth sounding device and the second bluetooth sounding device include: a buffer unit, which temporarily stores digital audio packets; a decoding unit, which is connected to the buffer unit and decodes samples of the digital audio packets; A sample conversion rate adjustment unit, connected to the decoding unit, and adjusting the sampling rate; and a digital-to-analog conversion unit, connected to the sample conversion rate adjustment unit, and converting the samples into analog audio signals.

In an embodiment of the audio synchronization method of the present invention, it includes the following steps: capturing the number of samples converted by the digital-to-analog conversion units of the first Bluetooth sounding device and the second Bluetooth sounding device at a first time point; and according to the first Bluetooth sounding device and The number of samples converted by the second bluetooth sounding device is adjusted, and the sampling rate of the sample conversion rate adjustment unit of the second bluetooth sounding device is adjusted.

In an embodiment of the audio synchronization method of the present invention, the method includes the following steps: comparing the number of samples converted by the digital-to-analog conversion units of the first bluetooth sounding device and the second bluetooth sounding device at a first time point.

In an embodiment of the audio synchronization method of the present invention, it includes a plurality of digital audio packets, and each digital audio packet includes a corresponding serial number, and each serial number is used to indicate the number of samples accumulated before each digital audio packet.

The present invention is described in detail below with reference to the accompanying drawings and specific embodiments, but is not intended to limit the present invention.

Description of drawings

FIG. 1 is a schematic structural diagram of an embodiment of the Bluetooth transmission system according to the present invention;

FIG. 2 is a schematic block diagram of an embodiment of the Bluetooth sound generating device according to the present invention;

3 is a flow chart of steps of an embodiment of an audio synchronization method for a Bluetooth sounding device according to the present invention;

4 is a flow chart of steps of another embodiment of the audio synchronization method of the Bluetooth sounding device according to the present invention;

5 is a schematic diagram of an embodiment of a digital audio packet according to the present invention;

6 is a schematic diagram of another embodiment of the digital audio packet according to the present invention;

FIG. 7 is a schematic diagram of another embodiment of the digital audio packet according to the present invention.

where the reference number

10 Bluetooth transmission system 11 Electronic device

12 Digital Audio Packets 121 First Packet

123 Second packet 124 Blank packet

125 The third packet 13 Bluetooth sound device

131 The first bluetooth sounding device 1311 Buffer unit

1313 Decoding unit 1315 Sample conversion rate adjustment unit

1317 Digital-to-analog conversion unit 133 Second Bluetooth sound device

1331 Buffer unit 1333 Decoding unit

1335 Sample Conversion Rate Adjustment Unit 1337 Digital-to-Analog Conversion Unit

14 Analog audio signal 161 First serial number

163 Second serial number 165 Third serial number

Detailed ways

Below in conjunction with accompanying drawing, structure principle and working principle of the present invention are described in detail:

Within the scope of the specification and the following claims, the term coupled or connected is used herein to include any means of direct and indirect electrical connection. Therefore, if a first device is described as being coupled to a second device, it means that the first device can be directly electrically connected to the second device, or indirectly electrically connected to the second device through other devices or connecting means.

FIG. 1 is a schematic structural diagram of an embodiment of the Bluetooth transmission system 10 according to the present invention, and FIG. 2 is a schematic block diagram of an embodiment of the Bluetooth sounding device 13 according to the present invention. In an embodiment of the present invention, the Bluetooth transmission system 10 mainly includes an electronic device 11 and a plurality of Bluetooth sounding devices 13 , wherein the electronic device 11 is not an essential structure. For the convenience of description, the Bluetooth sounding device 13 of the present invention includes a first Bluetooth sounding device 131 and a second Bluetooth sounding device 133 , wherein the first Bluetooth sounding device 131 and the second Bluetooth sounding device 133 can communicate via Bluetooth Make connections and transmit digital audio packets 12 . However, in different embodiments, the number of the Bluetooth sounding devices 13 may be more than two, and the plurality of Bluetooth sounding devices 13 can also be synchronized by the audio synchronization method of the present invention.

In an embodiment of the present invention, the first bluetooth sounding device 131 and the second bluetooth sounding device 133 can form a sound system, wherein the first bluetooth sounding device 131 can be the left channel, and the second bluetooth sounding device 133 can be the right channel sound. For a general two-channel sound system, it is usually necessary to synchronize the first Bluetooth sound device 131 and the second Bluetooth sound device 133 as much as possible, so that the sound system can be constructed with correct channels and achieve good audio-visual effects. If the number of the Bluetooth sounding devices 13 is more than two, each Bluetooth sounding device 13 also needs to be synchronized, so that a multi-channel sound system can be constructed.

In the embodiment of the present invention, the digital audio package 12 is originally stored in the electronic device 11, and the electronic device 11 can transmit the digital audio package 12 to the first Bluetooth sound device 131 through Bluetooth, and the first Bluetooth sound device 131 receives the digital audio package 12. After the audio packets 12 are received, the received digital audio packets 12 are transmitted to the second Bluetooth sounding device 133 through Bluetooth. Of course, the electronic device 11 is not an essential component of the present invention. The present invention is mainly applied to multiple Bluetooth sounding devices 13 and used to synchronize the audio of the multiple Bluetooth sounding devices 13. For example, the digital audio package 12 can be stored in the first Bluetooth sounding device 131. Inside, the first bluetooth sounding device 131 can transmit the digital audio packet 12 to the second bluetooth sounding device 133 through bluetooth.

In an embodiment of the present invention, the first Bluetooth sounding device 131 may be defined as a master device (Master), and the second Bluetooth sounding device 133 may be defined as a slave device (Slave). Before the first bluetooth sounding device 131 transmits the digital audio packet 12 to the second bluetooth sounding device 133 via bluetooth, a bluetooth connection between the first bluetooth sounding device 131 and the second bluetooth sounding device 133 must be established first.

First, pair the first Bluetooth sounding device 131 and the second Bluetooth sounding device 133 to synchronize the clocks of the first Bluetooth sounding device 131 and the second Bluetooth sounding device 133, and make them use the same clock. 's clock. During the pairing process, the first Bluetooth sounding device 131 will continue to send out inquiry packets. When the second Bluetooth sounding device 133 in the adjacent area receives the inquiry packet, for example, the nearby area is the wireless transmission range of Bluetooth, the second Bluetooth sounding device 133 A response packet is sent to the first Bluetooth sound device 131 , wherein the response packet includes the Bluetooth device address (BD_ADDR, bluetooth address) of the second Bluetooth sound device 133 .

After the first bluetooth sounding device 131 receives the response packet sent by the second bluetooth sounding device 133, it will send out a connection packet (page) according to the bluetooth device address of the response packet. Since the connection packet includes the Bluetooth device address, only the second Bluetooth sounding device 133 can receive the connection packet transmitted by the first Bluetooth sounding device 131 .

After the second bluetooth sounding device 133 receives the connection packet, the clock of the first bluetooth sounding device 131 can be known from the content of the connection packet, so that the second bluetooth sounding device 133 can communicate with the clock of the first bluetooth sounding device 131 For synchronization, for example, the first Bluetooth sounding device 131 and the second Bluetooth sounding device 133 use the same clock. Through the above steps, the bluetooth connection between the first bluetooth sounding device 131 and the second bluetooth sounding device 133 can be completed, so that the digital audio packet 12 can be transmitted between the first bluetooth sounding device 131 and the second bluetooth sounding device 133 through bluetooth .

The digital audio packet 12 is first transmitted to the first Bluetooth sound device 131 via the electronic device 11, and then the first Bluetooth sound device 131 transmits the received digital audio packet 12 to the second Bluetooth sound device 133. Therefore, the first Bluetooth sound device 133 131 and the second Bluetooth sounding device 133 receive the digital audio packet 12 at different times. After the first bluetooth sounding device 131 receives the digital audio packet 12, it will not immediately convert and play the audio packet 12, but will determine that after the second bluetooth sounding device 133 also receives the digital audio packet 12, the first bluetooth sounding device 131 and the second bluetooth sounding device 133 play sound signals at the same time, so that the sound signals played by the first bluetooth sounding device 131 and the second bluetooth sounding device 133 are synchronized in the initial stage.

As shown in FIG. 2 , the first Bluetooth sounding device 131 and the second Bluetooth sounding device 133 include a buffer unit (buffer) 1311/1331, a decoding unit (decode) 1313/1333, and a sample rate conversion unit (sample rate conversion) 1315/ 1335 and digital-to-analog conversion unit (DAC) 1317/1337, wherein the decoding unit 1313/1333 is connected to the buffer unit 1311/1331, and the sample conversion rate adjustment unit 1315/1335 is connected to the decoding unit 1313/1333 and the digital-to-analog conversion unit 1317 /1337.

Of course, in practical application, the first bluetooth sounding device 131 and the second bluetooth sounding device 133 may also require different structures such as a bluetooth transmission interface, a speaker, an amplifier unit, a microprocessor and/or a power supply, etc., in order to make the first bluetooth sounding device 131 and the second Bluetooth sounding device 133 operate. However, the above-mentioned structure has nothing to do with the content of the main description of this case, and has been disclosed in the prior art, so it is not shown in FIG. 2 for the convenience of description.

The buffer units 1311/1331 according to the embodiment of the present invention can be used to temporarily store the digital audio packets 12; the decoding units 1313/1333 can be used to decode the samples of the digital audio packets 12; the sample conversion rate adjustment units 1315/1335 can be used to adjust the sampling and digital to analog conversion units 1317/1337 may be used to convert samples of digital audio packets 12 into analog audio signals 14.

After receiving the digital audio packet 12, the first Bluetooth sounding device 131 temporarily stores the digital audio packet 12 in the buffer unit 1311, and transmits the digital audio packet 12 to the second Bluetooth sounding device 133 through Bluetooth.

After receiving the digital audio packet 12 sent by the first Bluetooth sounding device 131 , the second Bluetooth sounding device 133 also temporarily stores the digital audio packet 12 in the buffer unit 1331 . After both the first Bluetooth sounding device 131 and the second Bluetooth sounding device 133 have received the digital audio packets 12 , they can simultaneously process and play the digital audio packets 12 . For example, the first Bluetooth sound device 131 and the second Bluetooth sound device 133 have the same clock, so the first Bluetooth sound device 131 and the second Bluetooth sound device 133 can be set to process the digital audio packets 12 at the same clock point.

The digital audio packet 12 includes a plurality of samples, and the first Bluetooth sound device 131 and the second Bluetooth sound device 133 transmit the samples of the digital audio packet 12 to the decoding unit 1313/1333 for decoding. Then, the decoded samples are sent to the digital-to-analog conversion units 1317/1337 through the sample conversion rate adjustment unit 1315/1335, and the digital samples are converted into analog signals by the digital-to-analog conversion units 1317/1337, so that the first Bluetooth sounding device 131 and the second Bluetooth sounding device 133 play the analog audio signal 14 synchronously.

However, after a period of playback, the first Bluetooth sound device 131 and the second Bluetooth sound device 133 may play the audio due to the different speeds of the first Bluetooth sound device 131 and the second Bluetooth sound device 133 to process the digital audio packets 12 . The analog audio signal 14 is out of sync and affects the sound quality of the first Bluetooth sounding device 131 and the second Bluetooth sounding device 133 .

3 is a flow chart of steps of an embodiment of the audio synchronization method of the Bluetooth sounding device according to the present invention. Please refer to FIG. 1 and FIG. 2 in conjunction. An audio synchronization method is proposed. First, the sample count converted by each sounding unit 13 at the same time point is acquired, as shown in step 21 . Taking the first bluetooth sounding device sound unit 131 and the second bluetooth sounding device sound unit 133 as an example, the number of samples converted by the first bluetooth sounding device 131 and the second bluetooth sounding device 133 at the first time point can be captured. Get the number of samples converted by the digital-to-analog conversion units 1317/1337 of the first Bluetooth sounding device 131 and the second Bluetooth sounding device 133 at the first time point. In the embodiment of the present invention, the number of converted samples at the same time point is mainly captured. It should be noted that the same time point refers to non-simultaneity. In application, multiple sound generating units 13 can simultaneously capture the number of converted samples, and also The number of converted samples may not be captured at the same time.

Then, the number of samples converted by each Bluetooth sounding device 13 at the same time point can be further compared, as shown in step 23 . Taking the first bluetooth sounding device sound unit 131 and the second bluetooth sounding device sound unit 133 as an example, the number of samples converted by the first bluetooth sounding device 131 and the second bluetooth sounding device 133 at the first time point can be compared. The number of samples converted by the digital-to-analog conversion units 1317/1337 of the Bluetooth sounding device 131 and the second Bluetooth sounding device 133 at the first time point. If the number of samples converted by the first bluetooth sounding device 131 and the second bluetooth sounding device 133 are different at the first time point, it means that the first bluetooth sounding device 131 and the second bluetooth sounding device 133 are not synchronized.

According to the number of samples converted by the bluetooth sounding device 13 , the rate at which the bluetooth sounding device 13 converts samples is adjusted, as shown in step 25 . Taking the first bluetooth sounding device sound unit 131 and the second bluetooth sounding device sound unit 133 as an example, when the number of samples converted by the first bluetooth sounding device 131 and the second bluetooth sounding device 133 is different, it means that the two are not synchronized. The rate at which the first bluetooth sounding device 131 and/or the second bluetooth sounding device 133 converts samples can be adjusted.

In an embodiment of the present invention, if the first bluetooth sounding device 131 is the master device and the second bluetooth sounding device 133 is the slave device, the number of samples converted by the first bluetooth sounding device 131 and the second bluetooth sounding device 133 may be used. Or as a result of the comparison, adjust the rate at which the second bluetooth sounding device 133 converts samples, for example, the sampling rate of the sample conversion rate adjustment unit 1335 of the second bluetooth sounding device 133 can be adjusted so that the second bluetooth sounding device 133 and the first bluetooth sounding device The number of samples converted by 131 at the same time point is the same, so as to achieve the purpose of synchronizing the first Bluetooth sounding device 131 and the second Bluetooth sounding device 133 . Of course, in different embodiments, the rate at which the first bluetooth sounding device 131 converts samples can also be adjusted, or the rate at which the first bluetooth sounding device 131 and the second bluetooth sounding device 133 convert samples at the same time can make the first bluetooth sound. The device 131 and the second Bluetooth sounding device 133 are synchronized.

In addition, in an embodiment of the present invention, the above-mentioned step 23 can also be omitted, and the conversion rate of the bluetooth sounding device 13 can be directly adjusted by the number of converted samples, which can also achieve the purpose of synchronizing each bluetooth sounding device 13 .

Before performing step 21 in the embodiment of the present invention, the clocks of the first Bluetooth sounding device 131 and the second Bluetooth sounding device 133 can be synchronized, as in the embodiments described in FIG. 1 and FIG. 2 of the present invention. Repeat. In addition, since the first Bluetooth sounding device 131 and the second Bluetooth sounding device 133 use the same clock, the first time point can be defined by the clock, and the first and second Bluetooth sounding devices 131 and 133 can be captured at The number of samples transformed at the first time point.

FIG. 4 is a flow chart of steps of still another embodiment of the audio synchronization method of the Bluetooth sound generating device according to the present invention. Please refer to FIG. 1 and FIG. 2 together. For the convenience of description, the embodiment of the present invention is mainly described with two sounding units 13, but the number of sounding units 13 is not a limitation of the present invention, and can also be used in practical applications. The method of the present invention is applied to more than two sounding units 13 .

In the embodiment of the present invention, the first Bluetooth sounding device 131 is defined as a master device (Master), and the second Bluetooth sounding device 133 is defined as a slave device (Slave). The first bluetooth sounding device 131 and the second bluetooth sounding device 133 are paired and connected via bluetooth, so that the clocks of the first bluetooth sounding device 131 and the second bluetooth sounding device 133 are synchronized, wherein the first bluetooth sounding device 131 and the second bluetooth sound The pairing and connection methods between the sounding devices 133 have been described in the above-mentioned embodiments, and will not be repeated here.

Capture the number of samples converted by the first Bluetooth sound device 131 at the first time point, for example, capture the number of samples converted by the digital-to-analog conversion unit 1317 of the first Bluetooth sound device 131 at the first time point T1, and generate the first sample Quantity SC1, as shown in step 31. The first Bluetooth sound device 131 can transmit the first time point T1 and the first sample number SC1 to the second Bluetooth sound device 133 , as shown in step 33 .

After receiving the first time point T1 and the first number of samples SC1, the second Bluetooth sounding device 133 will capture the number of samples converted at the first time point T1, for example, the number of the second Bluetooth sounding device 133 The analog conversion unit 1337 converts the number of samples at the first time point T1 and generates a second number of samples SC2 , as shown in step 35 . Then, the first sample quantity SC1 and the second sample quantity SC2 also captured at the first time point T1 can be further compared, as shown in step 37 .

According to the first sample quantity SC1 and the second sample quantity SC2, or the comparison result of the first sample quantity SC1 and the second sample quantity SC2, the relationship between the first Bluetooth sounding device 131 and the second Bluetooth sounding device 133 can be known. whether to synchronize. If the two are not synchronized, the rate at which the second bluetooth sounding device 133 converts samples can be adjusted according to the number of converted samples or the comparison result of the number of samples, for example, adjusting the sampling rate of the sample conversion rate adjustment unit 1335 of the second bluetooth sounding device 133, So that the second bluetooth sounding device 133 and the first bluetooth sounding device 131 are synchronized, as shown in step 39 .

In addition, in an embodiment of the present invention, the above-mentioned step 37 can also be omitted, and the rate at which the bluetooth sounding device 13 converts samples is directly adjusted by the number of converted samples, which can also achieve the purpose of synchronizing each bluetooth sounding device 13 .

In the above-mentioned embodiments of the present invention, it is mentioned that the plurality of Bluetooth sound generating devices 13 capture the number of converted samples at the same time point and/or at the first time point. Since a plurality of Bluetooth sounding devices 13 have completed the clock synchronization during the process of Bluetooth connection, the clocks used by each Bluetooth sounding device 13 are the same. In an embodiment of the present invention, the clock of the Bluetooth sounding device 13 can be directly used as the calculation standard for the same time point and/or the first time point.

For example, each Bluetooth sounding device 13 can be set so that each Bluetooth sounding device 13 captures the number of converted samples when the number of clocks is one hundred or a multiple of one hundred, and depends on the number of converted samples or the number of samples. The results are compared, and the sampling rate of one or more Bluetooth sounding devices 13 is adjusted. In this way, in the process of using the bluetooth sounding device 13, the audio synchronization of each bluetooth sounding device 13 can be continuously performed.

In order to facilitate the description of the content of the present invention, in the following embodiments, the digital audio packets 12 and the samples are further quantified, as shown in Figures 5-7, of course, the defined quantity is only for the convenience of describing the content of the present invention, the quantity itself It is not a limitation of the present invention.

Please refer to FIG. 5 , the first bluetooth sounding device 131 and the second bluetooth sounding device 133 receive and convert the same digital audio packet 12 , wherein the digital audio packet 12 includes the first packet 121 , the second packet 123 and the third packet 125, and it is assumed that each packet 121/123/125 includes 100 samples. The converted number of samples captured by the first Bluetooth sounding device 131 at the first time point T1 is the sum of the first packet 121 , the second packet 123 and part of the third packet 125 . For example, the first Bluetooth sounding device 131 only converts the third packet 121 . If the number of samples in the packet 125 is 50, the number of samples converted by the first Bluetooth sound generating device 131 at the first time point T1 will be 250 samples.

In an ideal situation, the digital audio packets 12 converted by the first Bluetooth sound device 131 and the second Bluetooth sound device 133 should be identical, so the first Bluetooth sound device 131 and the second Bluetooth sound device 133 at the first point in time The number of samples for T1 upconversion should also be the same. In other words, if the second bluetooth sounding device 133 is synchronized with the first bluetooth sounding device 133, the number of samples converted by the second bluetooth sounding device 133 at the first time point T1 will also be 250 samples.

Therefore, if the number of samples converted by the second bluetooth sounding device 133 at the first time point T1 is greater than 250 samples, it means that the rate of the second bluetooth sounding device 133 converting samples is too fast, and it is necessary to reduce the conversion rate of the second bluetooth sounding device 133 The rate of samples so that the second bluetooth sounding device 133 is synchronized with the first bluetooth sounding device 131.

On the contrary, if the conversion number of samples captured by the second Bluetooth sound device 133 at the first time point T1 is less than 250 samples, it means that the rate of sample conversion by the second Bluetooth sound device 133 is too slow, and it is necessary to increase the second Bluetooth sound output Means 133 convert the rate of the samples. For example, the rate of converting samples can be adjusted by the sample conversion rate adjusting unit 1335 in the second Bluetooth sound emitting device 133 .

In the above-mentioned embodiments of the present invention, the rate at which the plurality of bluetooth sounding devices 13 convert samples is adjusted based on capturing and/or comparing the number of samples accumulated by the plurality of bluetooth sounding devices 13 at the same time point. Generally speaking, when the connection quality between each Bluetooth sounding device 13 is good, the above synchronization method will not cause any problems.

However, when the connection quality between the Bluetooth sounding devices 13 is poor, the transmitted digital audio packets 12 may be lost or delayed, and the accumulated number of samples may lose the function of judging whether the multiple Bluetooth sounding devices 13 are synchronized.

Please refer to FIG. 6 , when the transmission quality between the first Bluetooth sounding device 131 and the second Bluetooth sounding device 133 is poor, it may cause a time delay for the second Bluetooth sounding device 133 to receive the third packet 125 . Generally speaking, when a packet transmission delay occurs, the second Bluetooth audio device 133 usually fills up the blank packet 124 to fill the time when the second Bluetooth audio device 133 does not receive or process the third packet 125 . However, in this way, the number of samples converted by the second bluetooth sounding device 133 at the first time point T1 will include the blank packet 124 , which causes the first bluetooth sounding device 131 and the second bluetooth sounding device 133 to actually convert the digital audio packets 12 The number of samples is different, so that the accumulated number of samples loses the function of judging whether the plurality of Bluetooth sound-emitting devices 13 are synchronized.

Specifically, the digital audio packets 12 received and converted by the first Bluetooth sounding device 131 and the second Bluetooth sounding device 133 include the first packet 121 , the second packet 123 and part of the third packet 125 , and it is assumed that the first packet 121 , the first Both the second packet 123 and the third packet 125 include 100 samples, and the blank packet 124 includes 40 samples. If the number of sample conversions accumulated by the first Bluetooth sound device 131 at the first time point T1 is 250 samples, and the number of sample conversions accumulated by the second Bluetooth sound device 133 at the first time point T1 is also 250 samples, It should represent that the first Bluetooth sounding device 131 and the second Bluetooth sounding device 133 are synchronized at the first time point T1. However, in fact, the 250 samples converted by the second Bluetooth sound device 133 also include 40 samples of the blank packet 124, so the actual number of samples of the digital audio packet 12 converted by the second Bluetooth sound device 133 should be 210 Number of samples. In other words, when the transmission quality of the first bluetooth sounding device 131 and the second bluetooth sounding device 133 is poor, or there is an error in the number of accumulated samples, for example, the number of samples accumulated by the second bluetooth sounding device 133 additionally includes samples of the blank packet 124 If the number is too large, the audio synchronization method of the present invention will be ineffective.

In order to solve the above problems, each digital audio packet 12 of the present invention may include a corresponding sequence number, wherein the sequence number may be used to indicate the number of samples accumulated before each digital audio packet 12, for example, in the first packet 121, the first The second packet 123 and the third packet 125 are marked with a first sequence number 161, a second sequence number 163 and a third sequence number 165, respectively. The first sequence number 161 , the second sequence number 163 and the third sequence number 165 can be used to indicate the number of samples accumulated before the first packet 121 , the second packet 123 and the third packet 125 .

As shown in FIG. 7 , if the first packet 121 , the second packet 123 and the third packet 125 all include 100 samples, since there is no accumulated sample before the first packet 121 , the first sequence number 161 can be marked is 0. The second packet 123 has previously accumulated 100 samples of the first packet 121 , so the second sequence number 163 of the second packet 123 can be marked as 100. The third packet 125 has accumulated 200 samples of the first packet 121 and the second packet 123 before, so the third sequence number 165 of the third packet 125 can be marked as 200. When the number of samples converted by the second Bluetooth sound device 133 at the first time point T1 is captured, the number of samples converted by the second Bluetooth sound device 133 in the third packet 125 can be directly obtained from the third sequence number 165 on the third packet 125 Previously, 200 samples have been converted, such as the sum of the first packet 121 and the second packet 123, and the number of samples of the blank packet 124 is not calculated. In this way, even if there is a blank packet 124 between the second packet 123 and the third packet 125 , the number of samples for capturing the converted digital audio packet 12 by the second Bluetooth sound device 133 will not be affected.

Of course, as long as the above serial number can indicate the number of samples of the processed packets 12, it can solve the problem that the accumulated number of samples loses the function of judging whether the plurality of Bluetooth sounding devices 13 are synchronized. Therefore, how the serial number should indicate the number of samples of the packet 12 is not in the present invention. , as long as the serial number can indicate the correct number of samples.

Of course, the present invention can also have other various embodiments, without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding Changes and deformations should belong to the protection scope of the appended claims of the present invention.

Claims (11)

1. An audio synchronization method of a bluetooth sounding device, wherein the bluetooth sounding device comprises a first bluetooth sounding device and a second bluetooth sounding device, and the first bluetooth sounding device and the second bluetooth sounding device transmit a plurality of digital audio packets by bluetooth, which It is characterized in that it includes the following steps: The first bluetooth sounding device transmits the digital audio packets to the second bluetooth sounding device through bluetooth, wherein each digital audio packet includes a corresponding serial number, and each serial number is respectively used to indicate the number of samples accumulated before each digital audio packet; capturing the number of samples converted by the digital-to-analog conversion unit of the first Bluetooth sounding device at the first time point; When capturing the number of samples converted by the second bluetooth sounding device at the first time point, capture the serial number of the digital audio packet converted by the second bluetooth sounding device at the first time point, and know from the captured serial number that the digital audio packet is converted at the first time point. the number of samples that have been converted before the number of samples of the audio packet, wherein the second Bluetooth sound device determines the number of samples converted at the first point in time according to the number of samples that have been converted before the number of samples of the digital audio packet; and According to the number of samples converted by the first bluetooth sounding device and the second bluetooth sounding device at the first time point, the rate at which the second bluetooth sounding device converts samples is adjusted. 2 . The audio synchronization method according to claim 1 , further comprising the step of: comparing the number of samples converted by the first bluetooth sounding device and the second bluetooth sounding device at the first time point. 3 . 3 . The audio synchronization method of claim 1 , wherein the first Bluetooth sounding device is a master device, and the second Bluetooth sounding device is a slave device. 4 . 4. audio frequency synchronization method as claimed in claim 1, is characterized in that, comprises the following method: Capture the number of samples converted by the first Bluetooth sounding device and the second Bluetooth sounding device at the same time point. 5 . The audio synchronization method of claim 1 , comprising the following steps: synchronizing the clocks of the first Bluetooth sounding device and the second Bluetooth sounding device. 6 . 6. The audio synchronization method of claim 5, further comprising the steps of: pairing the first bluetooth sounding device with the second bluetooth sounding device, so that the first bluetooth sounding device and the second bluetooth sounding device use the same time pulse. 7 . The audio synchronization method of claim 6 , comprising the following steps: the first Bluetooth sounding device and the second Bluetooth sounding device define the first time point through a clock. 8 . 8. An audio synchronization method of a bluetooth sounding device, wherein the bluetooth sounding device comprises a first bluetooth sounding device and a second bluetooth sounding device, and the first bluetooth sounding device and the second bluetooth sounding device are connected by bluetooth and transmit a plurality of digital audio Packet, is characterized in that, comprises the following steps: The first bluetooth sounding device transmits the digital audio packets to the second bluetooth sounding device through bluetooth, wherein each digital audio packet includes a corresponding serial number, and each serial number is respectively used to indicate the number of samples accumulated before each digital audio packet; capturing the number of samples converted by the digital-to-analog conversion unit of the first bluetooth sounding device at the first time point, and generating the first number of samples; transmitting the first time point and the first sample quantity from the first Bluetooth sounding device to the second Bluetooth sounding device; Retrieve the number of samples converted by the second bluetooth sounding device at the first time point, and when the second number of samples is generated, extract the serial number of the digital audio packet converted by the second bluetooth sounding device at the first time point, and use the extracted serial number Knowing the number of samples that the second Bluetooth sound generator has converted before converting the number of samples of the digital audio packet, and determining the number of samples converted at the first time point according to the number of samples that have been converted before converting the number of samples of the digital audio packet ;and According to the first number of samples and the second number of samples, the rate at which the second bluetooth sounding device converts samples is adjusted. 9 . The audio synchronization method of claim 8 , further comprising the step of: comparing the number of samples converted by the first Bluetooth sounding device and the second Bluetooth sounding device at the first time point. 10 . 10 . The audio synchronization method of claim 8 , comprising the following steps: synchronizing the clocks of the first Bluetooth sounding device and the second Bluetooth sounding device. 11 . 11 . The audio synchronization method of claim 10 , comprising the following steps: the first Bluetooth sounding device and the second Bluetooth sounding device define the first time point through a clock. 12 .

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