A multi-channel audio transmission method based on power line carrier and network line

Abstract

The present invention discloses a multi-channel audio transmission method based on power line carrier and network line, which includes: establishing a communication connection with a sound source receiving end through a power line and a network line. If the network line is faulty, audio data is transmitted to the sound source receiving end through the power line; otherwise, audio data is transmitted to the sound source receiving end through the network line. The power line transmits audio data to one or more sound source receiving ends. The audio data packets of the audio data transmitted by the power line include a channel number and valid audio data representing the audio. Each sound source receiving end receives the audio data of the corresponding channel through its respective corresponding channel number. Compare the time differences brought by the audio data with the same packet sequence number to eliminate the phenomenon of sound loss caused by the lack of playing some audio data packets due to the transmission delays of the two lines, namely the power line and the network line. The present invention has low cost and can realize the transmission by switching different lines for audio transmission, avoiding the occurrence of sound loss.

Description

Technical Field

[0001] The present invention relates to the technical field of audio transmission, and specifically to a multi-channel audio transmission method based on power line carrier and network line. Background Art

[0002] For certain scenarios, such as the college entrance examination English listening test, currently an IP broadcast system is used to play English listening content, that is, the network transmission line is used to transmit the English listening content, and at the same time, an analog transmission line is set as a backup transmission line so that in the case of problems with the network transmission line, it can be transmitted through the analog transmission line to avoid affecting the examination. However, the existing analog transmission line can only transmit one signal, and it cannot meet the environment of more and more small languages taking the exam simultaneously. In addition, there are also problems of sound loss or repeated playback when using the network transmission line and the analog transmission line, that is, during the process of switching from one line to another, due to being out of sync, some audio data packets are not played or some audio data packets are repeatedly played, resulting in some sound loss or repeated playback. Generally speaking, the probability of missing some audio data packets and causing sound loss is greater. Summary of the Invention

[0003] Aiming at the deficiencies of the prior art, the purpose of the present invention is to provide a multi-channel audio transmission method based on power line carrier and network line, which can solve the problems described in the background art.

[0004] The technical solution for achieving the purpose of the present invention is: a multi-channel audio transmission method based on power line carrier and network line, including the following steps:

[0005] Step 1: Establish a communication connection with the sound source receiving end using the power line and the network line. If the network line is faulty, transmit audio data to the sound source receiving end using the power line; otherwise, transmit audio data to the sound source receiving end using the network line.

[0006] Step 2: Transmit audio data from the power line to one or more sound source receiving ends. The audio data packets of the audio data transmitted by the power line include a channel number and valid audio data representing the audio. Each sound source receiving end receives the audio data of the corresponding channel through its respective corresponding channel number.

[0007] Further, after step 2, it further includes step 3:

[0008] Step 3: Also include adding a packet sequence number to the audio data packets transmitted by the power line, and the audio data packets and the packet sequence numbers correspond one by one.

[0009] The audio source receiving end adjusts the buffer size of the audio data by comparing the audio data received from the network line transmission before switching and the audio data received from the power line transmission after switching, and comparing the time difference A between the audio data packets in the audio data transmitted by the network line and the audio data packets in the audio data transmitted by the power line with the same packet sequence number, so as to eliminate the phenomenon of sound loss caused by the lack of playing some audio data packets due to the transmission delays of the two lines of the power line and the network line by adjusting the buffer size.

[0010] Furthermore, the time difference A between the audio data packets in the audio data transmitted by the network line and the audio data packets in the audio data transmitted by the power line with the same packet sequence number is compared to adjust the buffer size of the audio data, so as to eliminate the phenomenon of sound loss caused by the lack of playing some audio data packets due to the transmission delays of the two lines of the power line and the network line by adjusting the buffer size. The specific implementation process includes the following steps:

[0011] The buffer quantity HC calculated according to formula ① is used to adjust the buffer size of the audio data of the audio source receiving end, and after buffering the audio data of size HC, start playing:

[0012]

[0013] In the formula, A represents the time difference A between the audio data packets in the audio data transmitted by the network line and the audio data packets in the audio data transmitted by the power line with the same packet sequence number, T2 represents that the audio source receiving end receives the audio data packet with packet sequence number x from the power line, T1 represents that the audio source receiving end receives the audio data packet with packet sequence number x from the network line, α represents the weight value, represents rounding up, SA′ and SA are intermediate variables, where SA′ i represents the intermediate variable for calculating the audio data packet corresponding to the i-th packet sequence number, SA′ i represents the intermediate variable for calculating the audio data packet corresponding to the (i - 1)-th packet sequence number, CY represents the sampling rate, TD represents the number of channels, WL refers to the bit rate,

[0014] After the audio source receiving terminal buffers the audio data of size HC, that is, buffers a number of audio data packets, and starts playing the received audio data packets after the total data volume of the buffered audio data packets reaches HC.

[0015] Furthermore, α = 0.8.

[0016] Furthermore, in step 1, the audio data is transmitted using the power line or the network line by switching between the power line and the network line.

[0017] Further, the specific implementation of transmitting audio data using a power line or a network line by switching between the power line and the network line includes the following steps:

[0018] A control switch and a line status detection module are set at the sound source receiving end. The line status detection module is used to detect the line status of the power line and the network line. If the line status of the network line is normal, the control switch automatically switches to the network line, so that the sound source sending end establishes a communication connection with the sound source receiving end through the network line, and thus sends audio data to the sound source receiving end through the network line; if the line status of the network line is abnormal, the control switch automatically switches to the power line, so that the sound source sending end establishes a communication connection with the sound source receiving end through the power line, and thus sends audio data to the sound source receiving end through the power line.

[0019] Further, detecting the line status of the network line means detecting whether the network line can perform network communication normally, that is, detecting whether the network is disconnected. If the network is disconnected, it is considered that the network line is faulty.

[0020] Further, play the audio data packet in the cached audio data packets that has the same packet sequence number as the last audio data packet received from the network line before switching or the packet sequence number of the packet after the last audio packet.

[0021] Further, starting from the audio data corresponding to the first packet sequence number, calculate SA′ by calculating the time difference A between the two lines, and then calculate the time difference A between the two lines for the current next packet sequence number and the previous SA′ to obtain the intermediate variable SA′ corresponding to the next packet sequence number, so as to adjust the cache size according to the real-time time difference between the lines, so that the first audio data packet in the cache size is the audio data packet with the same packet sequence number or the next packet sequence number as the last audio data packet received from the network line before switching, and play the first audio data packet in the cache after switching.

[0022] The beneficial effects of the present invention are as follows: The present invention can realize multi-channel audio transmission based on the existing network line and power line resources, without the need to transform the original line, with less construction and low cost, and can realize audio transmission by switching different lines. And it can also calculate the time difference caused by the delay of the two lines, and avoid the occurrence of sound loss by adjusting the cache size to ensure stable audio output, with better effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic flow chart of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0024] Next, in combination with the drawings and specific implementation schemes, the present invention will be further described:

[0025] As Figure 1 shown, a multi-channel audio transmission method based on power line carrier and network line includes the following steps:

[0026] Step 1: Set a control switch and a line status detection module at the sound source receiving end. The line status detection module is used to detect the line status of the power line and the network line. If the line status of the network line is normal, the control switch automatically switches to the network line, so that the sound source receiving end receives the audio data sent from the sound source sending end through the network line, that is, the sound source sending end sends the audio data to the sound source receiving end through the network line. If the line status of the network line is abnormal, that is, a fault occurs, the control switch automatically switches to the power line, so that the sound source sending end establishes a communication connection with the sound source receiving end through the power line, and thus sends the audio data to the sound source receiving end through the power line.

[0027] Among them, detecting the line status of the network line is mainly to detect whether the network line can perform network communication normally, that is, to detect whether the network is disconnected. Once it is detected that the network of the network line is disconnected, it directly switches to the power line, and the power line is used to transmit the audio. The power line can transmit multiple channels of audio simultaneously through power line carrier technology, so that audio signals of multiple languages can be transmitted simultaneously, meeting the multi-language test requirements such as college entrance examination or other languages.

[0028] Step 2: The audio data packet in the audio data transmitted to the sound source receiving end through the power line includes a channel number and valid audio data representing the audio. The sound source receiving end only receives the audio data of the channel where the current sound source receiving end is located. That is, the sound source sending end is connected to multiple sound source receiving ends through the power line, and a channel number is set on the audio data packet of the audio data. Different sound source receiving ends correspond to a channel number, so that the sound source receiving end can receive the corresponding audio data, so that the sound source sending end can transmit multiple channels of audio data simultaneously through a power line, realizing the transmission of multi-language audio data. For example, the sound source receiving end in the English listening test classroom only receives the English audio data through the channel number, and the sound source receiving end in the Japanese listening test classroom only receives the Japanese audio data through the channel number.

[0029] Among them, the sound source receiving end parses the received audio data and parses out the packet header. The channel number can be obtained from the packet header. If it is the audio data required by the current sound source receiving end, it is decoded and played, otherwise it can be directly discarded.

[0030] By transmitting audio on the power line, while supplying power to the device (such as the sound source sending end and the sound source receiving end), the sound source receiving end can also play the audio, preventing the device from suddenly crashing and unable to continue providing the audio playback function.

[0031] Step 3: During the process of switching from the network line to the power line, due to possible delay phenomena, there may be a phenomenon of sound loss during this line switching process. To avoid the situation of sound loss due to out-of-sync sound when switching from network line transmission to power line transmission, it also includes adding packet sequence numbers to the audio data packets transmitted over the power line. Different audio data packets use different packet sequence numbers. Different packet sequence numbers mean different audio data packets. Each audio data packet corresponds to a unique packet sequence number, and a packet sequence number also uniquely corresponds to an audio data packet. The sound source receiving end compares the audio data received from the network line transmission with the audio data received from the power line transmission, and compares the time difference A between the audio data packets in the audio data transmitted over the network line and the audio data packets in the audio data transmitted over the power line with the same packet sequence number. And the buffer quantity HC calculated according to formula ① is used to adjust the buffer size of the audio data at the sound source receiving end, and after buffering the audio data of size HC, the playback starts:

[0032]

[0033] In the formula, T2 represents the audio data packet with packet sequence number x received by the sound source receiving end from the power line, T1 represents the audio data packet with packet sequence number x received by the sound source receiving end from the network line. The x in the packet sequence number is not specifically limited, and only represents the time difference of the audio data packets that need to be compared with the same packet sequence number. α represents the weight value, and in this embodiment, it takes 0.8. represents rounding up, that is, taking the smallest integer greater than inside, for example, then take the integer 5. SA′ and SA are intermediate variables. Among them, SA′ i represents the intermediate variable for calculating the audio data packet corresponding to the i-th packet sequence number, SA′ i represents the intermediate variable for calculating the audio data packet corresponding to the (i - 1)-th packet sequence number. CY represents the sampling rate, that is, the sampling rate of the audio data. TD represents the number of channels, that is, the number of channels for transmitting audio over the power line. WL refers to the bit rate, that is, the code rate, which is the amount of audio data transmitted by a single channel per unit time.

[0034] That is, after the sound source receiving terminal buffers the audio data of size HC, that is, buffers a number of audio data packets, and after the total data volume of these buffered audio data packets reaches HC, it starts to play the received audio data packets. Thus, the buffer size can be dynamically adjusted according to the delay situation of the two lines in the actual situation to achieve sound synchronization and avoid sound loss.

[0035] In an alternative embodiment, the audio data packet in the cache with the same packet sequence number as the last audio data packet received from the network line before the handover or the packet sequence number of the packet after the last audio packet is played, so as to achieve seamless handover playback and avoid sound loss.

[0036] In another alternative embodiment, since SA′ is continuously updated in Formula 1, that is, the current SA′ is obtained based on the previously obtained SA′, therefore, starting from the audio data corresponding to the first packet sequence number, SA′ is calculated by comparing the time difference A between the two lines, and then the intermediate variable SA′ corresponding to the next packet sequence number can be calculated by comparing the time difference A between the two current lines and the previous SA′, so that the cache size can be adjusted according to the real-time time difference between the lines, making the first audio data packet in the cache almost the audio data packet with the same packet sequence number or the next packet sequence number as the last audio data packet received from the network line before the handover. Therefore, without comparing the packet sequence numbers of the audio data packets, the first audio data packet in the cache can be directly played after the handover, and seamless handover playback can also be achieved to avoid sound loss.

[0037] The present invention can realize multi-channel audio transmission based on existing network lines and power line resources, without the need to transform the original lines, with less construction work and low cost, and can also realize audio transmission by switching different lines. Moreover, it can calculate the time difference caused by the delay of the two lines, and avoid sound loss by adjusting the cache size to ensure stable audio output, with better effects.

[0038] The embodiments disclosed in this specification are only an illustration of the unilateral features of the present invention. The protection scope of the present invention is not limited to these embodiments, and any other functionally equivalent embodiments fall within the protection scope of the present invention. For those skilled in the art, various corresponding changes and deformations can be made according to the technical solutions and concepts described above, and all these changes and deformations should fall within the protection scope of the claims of the present invention.

Claims

1. A multi-channel audio transmission method based on power line carrier and network lines, characterized in that, It includes the following steps: Step 1: Establish a communication connection with the sound source receiving end using the power line and the network line. If the network line is faulty, transmit the audio data to the sound source receiving end using the power line; otherwise, transmit the audio data to the sound source receiving end using the network line. Step 2: The power line transmits the audio data to one or more sound source receiving ends. The audio data packets of the audio data transmitted by the power line include the channel number and the valid audio data representing the audio. Each sound source receiving end receives the audio data of the corresponding channel through its respective corresponding channel number. After Step 2, it further includes Step 3: Step 3: It also includes adding a packet sequence number to the audio data packets transmitted by the power line. The audio data packets and the packet sequence numbers correspond one by one. The sound source receiving end adjusts the buffer size of the audio data by comparing the audio data packets received from the network line transmission and the audio data packets received from the power line transmission, and comparing the time difference A between the audio data packets in the audio data transmitted by the network line and the audio data packets in the audio data transmitted by the power line with the same packet sequence number. Thus, by adjusting the buffer size, the phenomenon of sound loss caused by the lack of playing some audio data packets due to the transmission delays of the power line and the network line is eliminated. The process of comparing the time difference A between the audio data packets in the audio data transmitted by the network line and the audio data packets in the audio data transmitted by the power line with the same packet sequence number to adjust the buffer size of the audio data, and thus eliminating the phenomenon of sound loss caused by the lack of playing some audio data packets due to the transmission delays of the power line and the network line, its specific implementation process includes the following steps: The buffer quantity HC calculated according to Formula ① adjusts the buffer size of the audio data of the sound source receiving end, and starts playing after buffering the audio data of size HC: ------① Wherein, A represents the time difference A between the audio data packets transmitted via the network line with the same packet sequence number and the audio data packets transmitted via the power line, represents that the audio data packet with packet sequence number x is received by the sound source receiving end from the power line, represents that the audio data packet with packet sequence number x is also received by the sound source receiving end from the network line, represents the weight value, represents rounding up, and SA is an intermediate variable, where, represents the intermediate variable for calculating the audio data packet corresponding to the i-th packet sequence number, represents the intermediate variable for calculating the audio data packet corresponding to the (i - 1)-th packet sequence number, CY represents the sampling rate, TD represents the number of channels, and WL refers to the bit rate, After the sound source receiving terminal buffers the audio data of size HC, that is, it buffers a number of audio data packets, and starts playing the received audio data packets after the total data volume of these buffered audio data packets reaches HC.

2. The multi-channel audio transmission method based on power line carrier and network line according to claim 1, characterized in that, =0.8。 3. The multi-channel audio transmission method based on power line carrier and network line according to any one of claims 1-2, characterized in that, In Step 1, the power line or the network line is used to transmit the audio data by switching between the power line and the network line.

4. The multi-channel audio transmission method based on power line carrier and network line according to any one of claims 1-2, characterized in that, The specific implementation of using the power line or the network line to transmit the audio data by switching between the power line and the network line includes the following steps: A control switch and a line status detection module are set at the sound source receiving end. The line status detection module is used to detect the line status of the power line and the network line. If the line status of the network line is normal, the control switch automatically switches to the network line, so that the sound source sending end establishes a communication connection with the sound source receiving end through the network line, and thus transmits the audio data to the sound source receiving end through the network line; if the line status of the network line is abnormal, the control switch automatically switches to the power line, so that the sound source sending end establishes a communication connection with the sound source receiving end through the power line, and thus transmits the audio data to the sound source receiving end through the power line.

5. The multi-channel audio transmission method based on power line carrier and network line according to claim 4, characterized in that, Detecting the line status of the network line means detecting whether the network line can perform network communication normally, that is, detecting whether the network is disconnected. If the network is disconnected, it is regarded that the network line is faulty.

6. The multi-channel audio transmission method based on power line carrier and network line according to claim 5, wherein Play the audio data packet in the cached audio data packets that has the same packet sequence number as the last audio data packet received from the network line before handover or the packet sequence number of the packet after the last audio packet.

7. The multi-channel audio transmission method based on power line carrier and network line according to claim 6, characterized in that Starting from the audio data corresponding to the first packet sequence number, it is calculated by comparing the time difference A between two lines. , and then calculate the time difference A between the two lines of the current next packet sequence number and the previous one to obtain the intermediate variable corresponding to the next packet sequence number , so as to adjust the cache size according to the real-time time difference between the lines, so that the first audio data packet in the cache size is the audio data packet with the same packet sequence number or the next packet sequence number of the last audio data packet received from the network line before the switch, and play the first audio data packet in the cache after the switch.

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