CN103514922A - Audio playing method, media controller, media player and media server - Google Patents

Abstract

The present invention discloses an audio playing method, a media controller, a media player and a media server. The digital media player comprises a digital video media player and at least one digital audio media player. The method comprises: detecting an audio playing time difference between the digital video media player and the at least one digital audio media player; and controlling the audio playing of the at least one digital audio media player according to the audio playing time difference, so that the audio playing of the at least one digital audio media player is synchronized with the audio playing of the digital video media player.

Description

Method for playing audio, media controller, media player and media server

technical field

The present invention relates to audio playback technology, and in particular to a method for synchronizing audio playback of a plurality of digital media renderers (DMR) and related digital media controllers, digital media servers and digital audio media players.

Background technique

The goal of the Digital Living Network Alliance (DLNA) is to establish a set of industrial standards that can make the products of various manufacturers interconnect and adapt to each other, so as to realize digital life for consumers, and the specifications of the Digital Living Network Alliance are also applied. In the home digital audio-visual media playback system, it includes a digital media controller (digital media controller, DMC), a digital media server (digital media server, DMS) and a plurality of digital media players (digital media render, DMR). However, when the plurality of digital media players are wirelessly connected to the digital media server and the digital media controller, the plurality of digital media players receive audio data from the digital media server in a wireless manner. The advantage of audio playback is to reduce the configuration of the line and increase the flexibility of equipment changes in the future. However, the disadvantage is that the stability of wireless transmission is not as stable as that of wired transmission. , there may be obvious out-of-synchronization among the plurality of digital media players. Even under a stable connection, the slight difference between the oscillator frequency of each digital media player will gradually cause the audio playback to become out of sync due to long-term playback. Therefore, how to control and synchronize the multiple digital media players has become an urgent problem in this field.

Traditionally, the concept of an absolute time is used for synchronizing multiple digital media players. Further, each digital media player will obtain an absolute time information and follow it. However, many systems, including the DLNA, do not provide absolute time information for the sake of simplification, which would hinder traditional approaches here. Therefore, an innovative synchronization design is needed to solve the synchronization problem among multiple digital media players.

Contents of the invention

One of the objectives of the present invention is to provide a method for synchronizing audio playback of multiple digital media players and related devices to solve the above problems.

According to a first embodiment of the present invention, a method for synchronizing audio playback of multiple digital media players is disclosed. The plurality of digital media players include a digital audio-visual media player and at least one digital audio media player. The method includes detecting an audio playback time difference between the digital audio-visual media player and the at least one digital audio media player; and controlling the audio playback of the at least one digital audio media player according to the audio playback time difference, so as to The audio playback of the at least one digital audio media player is synchronized with the audio playback of the digital video audio media player.

According to a second embodiment of the present invention, a digital media controller for synchronizing a plurality of digital media players is disclosed. The plurality of digital media players include a digital audio-visual media player and at least one digital audio media player. The digital media controller includes a detection circuit and a control circuit. The detection circuit is used for detecting an audio playing time difference between the digital audio-visual media player and the at least one digital audio media player. The control circuit is coupled to the detection circuit, and is used to control the audio playback of the at least one digital audio media player according to the audio playback time difference, so that the audio playback of the at least one digital audio media player is synchronized with the digital audio-visual Audio playback for media players.

According to a third embodiment of the present invention, a digital audio media player is disclosed, including an audio playback adjustment circuit and a control circuit. The control circuit is used to receive a mismatched relative time position from a digital media controller, and control the audio playback adjustment circuit according to the mismatched relative time position, so that the audio playback of the digital audio media player is synchronized with a digital audio media player. The audio playback of the audio-visual media player, wherein the mismatch relative time position corresponds to an audio playback time difference between the digital audio-visual media player and the digital audio-visual media player.

According to a fourth embodiment of the present invention, a digital media server is disclosed, including a packet processing circuit and an audio playback adjustment circuit. The packet processing circuit is used for generating audio packets. The audio playback adjustment circuit is used for receiving a control signal from at least one digital media controller to adjust the audio package provided to the at least one digital media player.

In a digital media playback system, especially in a wireless digital media playback system, due to the instability of the transmission or the initial state, the method proposed by the present invention can be applied to this digital media playback system, so that the digital audio media playback Audio playback between devices is synchronized.

Description of drawings

FIG. 1 is a schematic diagram of an embodiment of a digital media playing system of the present invention.

FIG. 2 is a flow chart of an embodiment of a method for synchronizing audio playback of a digital audio-visual media player and at least one digital audio media player according to the present invention.

FIG. 3 is a flow chart of an embodiment of the steps of detecting an audio playback time difference between the digital audio-visual media player and the digital audio media player shown in FIG. 2 .

Fig. 4 controls the audio playback of the digital audio media player according to the audio playback time difference shown in Fig. 2, so that the audio playback of the digital audio media player is synchronized with an embodiment of the steps of the audio playback of the digital audio-visual media player flow chart.

FIG. 5 is a schematic diagram of an embodiment of the digital media controller shown in FIG. 1 .

FIG. 6 is a flow chart of an embodiment of the step of generating a mismatch relative time position according to the audio playback time difference shown in FIG. 4 .

FIG. 7 is a flow chart of an embodiment of a method for controlling audio playback of a digital audio media player according to mismatched relative time positions of the present invention.

FIG. 8 is a schematic diagram of a first embodiment of the digital audio media player shown in FIG. 1 .

FIG. 9 is a schematic diagram of an embodiment of the digital media server shown in FIG. 1 .

FIG. 10 is a flowchart of a first embodiment of a method for controlling audio playback of a digital audio media player according to the number of digital audio packets and the number of digital audio bits of the present invention.

FIG. 11 is a schematic diagram of a second embodiment of the digital audio media player shown in FIG. 1 .

FIG. 12 is a flow chart of a second embodiment of the method for controlling audio playback of a digital audio media player according to the number of digital audio packets and the number of digital audio bits of the present invention.

FIG. 13 is a schematic diagram of a third embodiment of the digital audio media player shown in FIG. 1 .

Wherein, the reference signs are explained as follows:

100: Digital media playback system

102, 900: digital media server

104, 500: digital media controller

106: Multiple Digital Media Players

108, 1100: digital audio-visual media player

110, 800, 1300: Digital Audio Media Player

202, 204, 302, 304, 306, 402, 404, 602, 604, 606, 608, 702, 704, 1002, 1004, 1202, 1204: steps

502: Detection circuit

504, 808, 1302: control circuit

512: judgment unit

514: PLL unit

516: switch unit

802: Audio Packet Analyzer

804: Audio Packet Decoder

806, 904, 1102: audio playback adjustment circuit

810: relative time position storage

902: Packet processing circuit

1112: the first audio playback adjustment unit

1114: Second audio playback adjustment unit

Detailed ways

Certain terms are used in the specification and subsequent claims to refer to particular elements. It should be understood by those skilled in the art that manufacturers may refer to the same element by different terms. This description and subsequent patent applications do not use the difference in name as a way to distinguish components, but use the difference in function of components as a criterion for distinguishing. The "comprising" mentioned throughout the specification and subsequent claims is an open term, so it should be interpreted as "including but not limited to". In addition, the term "coupled" herein includes any direct and indirect means of electrical connection. Therefore, if it is described that a first device is coupled to a second device, it means that the first device may be directly electrically connected to the second device, or indirectly electrically connected to the second device through other devices or connection means.

In a digital media playback system, multiple digital media players may include a digital audio-visual media player (such as a DVD player) and at least one digital audio media player (such as a home theater or 5.1-channel stereo speakers) In general applications, there is usually only one video playback, but there are often more than one sound playback. In some newer applications, not only for the integration of multiple audio playback devices, but even in a wireless transmission environment. The digital media controller controls to transmit a digital audio data or a digital audio-visual data from a digital media server to the at least one digital audio media player and the digital audio-visual media player for real-time playback. Due to the instability of the transmission or the initial state, it is often impossible to guarantee that the audio playback between the digital audio-visual media player and the at least one digital audio media player in the digital media playback system will always be synchronized, and must be directly or indirectly Time-related information can be used to monitor and be corrected at any time.

Please refer to FIG. 1 , which is a schematic diagram of an embodiment of a digital media playing system of the present invention. In this embodiment, the digital media playback system 100 includes a digital media server 102, a digital media controller 104, and a plurality of digital media players 106 (for example, a digital audio-visual media player 108 and at least one digital audio media player 110) Please note that the digital audio-visual media player 108 (such as a DVD player) has the functions of video playback and audio playback, while the digital audio media player 110 (such as a home theater or 5.1-channel stereo speaker) only has the function of audio playback . Because the operation of synchronizing the audio playback of a digital audio-visual media player and a digital audio media player can be easily extended to the operation of synchronizing the audio playback of a digital audio-visual media player and a plurality of digital audio media players, therefore, without affecting Under the technical disclosure of the present invention, for the sake of brevity, only one digital audio media player is shown in FIG. 1 . Actually, the digital media playback system 100 may also be provided with multiple digital audio media players.

The digital media server 104 will respectively provide the digital audio-visual data M _AV and the digital audio data _MA to the digital audio-visual media player 108 and the digital audio media player 110, therefore, the digital audio-visual media player 108 and the digital audio media player 110 will be based on Digital audio-visual data M _AV and digital audio data M _A are used for audio playback respectively. As mentioned above, due to the instability of transmission or initial state, it is often impossible to ensure that the digital audio-visual media player 108 in the digital media playback system 100 And the audio playback between the digital audio media player 110 is always synchronized, therefore, in this embodiment, the digital media server 104 will control the communication between the digital audio-visual media player 108 and the digital audio media player 110 through appropriate design Synchronization of audio playback.

Please refer to FIG. 2 , which is a flowchart of an embodiment of a method for synchronizing audio playback of a digital audio-visual media player and at least one digital audio media player according to the present invention. If generally the same result can be achieved, it is not necessary to follow the sequence of steps in the process shown in Figure 2, and the steps shown in Figure 2 do not have to be performed continuously, that is, other steps can also be inserted therein, In addition, some steps in FIG. 2 may also be omitted according to different embodiments or design requirements. For example (but the present invention is not limited thereto), the digital media server 104 can use this method to synchronize the audio playback of the digital audio-visual media player 108 and the digital audio media player 110, and the method includes the following steps:

Step 202: detect an audio playback time difference dRT _1AV between the digital audio-visual media player 108 and the digital audio media player 110; and

Step 204: Control the audio playback of the digital audio media player 110 according to the audio playback time difference dRT _1AV , so that the audio playback of the digital audio media player 110 is synchronized with the audio playback of the digital audio-visual media player 108 .

According to the embodiment shown in Fig. 2 of the present invention, in step 202, the audio playback time difference dRT _1AV is when playing digital audio-visual data M _AV and digital audio data _MA , due to some factors, the difference between digital audio-visual media player 108 and A relative time difference between the digital audio media players 110, i.e. the asynchronous playback, for example (but the present invention is not limited to this example), if the digital media server 102 is wirelessly connected to the digital audio media players 110 respectively and digital audio-visual media player 108 to link, each link will have different distances, different interferences and different channel models respectively, that is to say, digital audio data M _A and digital audio-visual data M _AV from digital media server 102 The arrival time of the digital audio media player 110 and the digital audio-visual media player 108 may be inconsistent, and another example (the present invention is not limited to this example), when a plurality of digital media players 106 for wireless transmission or When adding other special active functions, it is necessary to have independent digital circuits to process digital audio-visual data M _AV or digital audio data M _A and convert it to analog audio data. In other words, multiple digital media players 106 The multiple digital circuits respectively set in have their own clock sources, and there is no guarantee that the respective clock sources are exactly the same, that is, there will be a frequency error between the respective clock sources. Once accumulated for a period of time , the frequency error may create a noticeable out-of-sync problem that needs to be compensated. In addition, the digital media controller 108 can adopt any feasible way to obtain the audio playback time difference dRT1AV, for example (but the present invention is not limited thereto), it can be processed by the digital audio media player 108 and the digital audio-visual media player 110 transmits information implicitly containing time clues to obtain the audio playback time difference dRT _1AV , and the detailed implementation method will be described in later embodiments.

Normally, in order to maintain the most correct relationship between the picture and the image, the image and sound played by the digital audio-visual media player 108 will be used as the main reference object in the digital media playback system 100 (in other words, the digital audio-visual media player 108 108 will be used as a reference for other digital media players), therefore, according to the audio playback time difference dRT _1AV , the audio playback of the digital audio media player 110 is controlled to follow the digital audio-visual media player 108, so that the digital audio media player The audio playback of 110 is synchronized with the audio playback of the digital audio-visual media player 108 , as shown in step 204 . In this way, through the audio playback time difference dRT _1AV , it can be known that the audio playback between the digital audio-visual media player 108 and the digital audio media player 110 is not synchronized, so the digital audio media can be accelerated or slowed down according to the audio playback time difference dRT _1AV The audio playback speed of the player 110 is two.

Please refer to FIG. 3 , which is a flowchart of an embodiment of step 202 shown in FIG. 2 . If substantially the same result can be achieved, it is not necessary to follow the order of the steps in the process shown in Figure 3, and the steps shown in Figure 3 do not have to be performed continuously, that is, other steps can also be inserted therein, in addition , some steps in FIG. 3 may also be omitted according to different embodiments or design requirements. In this embodiment, the detailed operations of step 202 may include the following steps:

Step 302: Receive a video playback relative time position RT _AV from the digital video media player 108;

Step 304: Receive an audio playback relative time position _RT1 from the digital audio media player 110; and

Step 306 : Calculate the time difference between the video playback relative time position RT _AV and the audio playback relative time position RT ₁ as the audio playback time difference dRT _1AV .

Please note that the relative time position (relative time position) RT _AV of video playback in step 302 is transmitted from the digital video media player 108 to the digital media controller 104, and the timing of transmission can be that the digital media controller 104 actively controls the digital video video. After the media player 108 requests the REQ _AV , the digital audio-visual media player 108 may actively send out the REQ AV at regular intervals. However, this is for illustration purposes, and the provided embodiments are not intended to limit the scope of the present invention. In addition, the relative time position RT _AV of video and audio playback may contain information such as the length of the digital audio data _MA and the time position currently being played at the current time point. Similarly, the same is true for the relative time position _RT1 of audio playback in step 304 . Therefore, the digital audio-visual media player 108 will output the relative time position _RT1 of audio playback in response to the request REQ ₁ or actively send it out regularly. The time difference between the relative time position RT _AV of video playback and the relative time position RT ₁ of audio playback can also be regarded as the time difference dRT _1AV of audio playback, and the action of synchronizing audio playback is to make the relative time position RT _AV of video playback and the relative time position of audio playback relative to The time difference of the time position _RT1 is reduced to zero, that is, it is desired to reduce the audio playback time difference to zero.

Please refer to FIG. 4 , which is a flowchart of an embodiment of step 204 shown in FIG. 2 . If substantially the same result can be achieved, it is not necessary to follow the order of the steps in the process shown in FIG. 4 , and the steps shown in FIG. 4 do not have to be performed consecutively, that is, other steps can also be inserted therein. In addition, some steps in FIG. 4 may also be omitted according to different embodiments or design requirements. The detailed operation of step 204 may include the following steps:

Step 402: Generate a mismatching relative time position (mismatching relative time position) MRTP ₁ according to the audio playback time difference dRT _1AV ; and

Step 404: Control the audio playback of the digital audio media player 110 according to the mismatch relative time position MRTP ₁ .

In an embodiment of the present invention, the digital media controller 104 will generate a mismatch relative time position MRTP ₁ according to the audio playback time difference dRT _1AV as a control output for controlling the audio playback of the digital audio media player 110. Therefore, step 402 The mismatched relative time position MRTP ₁ in is obtained by performing a correlation operation on the audio playback time difference dRT _1AV , and the detailed implementation method will be described in later embodiments. In addition, the digital media controller 104 will directly or indirectly control the audio playback of the digital audio media player 110 to follow the reference object according to the mismatch relative time position MRTP ₁ , so that the audio playback of the digital audio media player 110 is synchronized with the digital audio-visual media The audio playback by the player 108 is shown in step 404 .

Please refer to FIG. 5 , which is a schematic diagram of an embodiment of the digital media controller 104 shown in FIG. 1 . The digital media controller 104 can be implemented by the digital media controller 500 . The digital media controller 500 is used to synchronize the audio playback of multiple digital media players. As shown in the figure, the digital media controller 500 includes a detection circuit 502 and a control circuit 504 coupled to the detection circuit 502, wherein the detection The detection circuit 502 is used to perform the operation of the above-mentioned step 202, and the control circuit 504 is used to perform the operation of the above-mentioned step 204. In other words, the detection circuit 502 is used to detect the relative time position RTAV and the audio-visual position of the digital audio-visual media player 108 The audio playback time difference dRT _1AV between the audio relative time positions RT1 of the digital audio media player 110, and the control circuit 504 is used to output the mismatch relative time position MRTP ₁ according to the audio playback time difference dRT _1AV to directly or indirectly control the digital audio media The audio playback of the player 110 is to synchronize the audio playback of the digital audio media player 110 with the audio playback of the digital audio-visual media player 108 . In this embodiment, the control circuit 504 includes a judging unit 512, a phase-locked loop unit 514, and a switching unit 516, wherein the detection circuit 502 is respectively coupled to the judging unit 512, the phase-locked loop unit 514, and the switching unit 516. The unit 512 is coupled to the PLL unit 514 and the switching unit 516 respectively. The control circuit 504 can use the method shown in FIG. 6 to obtain the mismatch relative time position MRTP ₁ .

Please refer to FIG. 5 and FIG. 6 together. FIG. 6 is a flowchart of an embodiment of step 402 shown in FIG. 4 . If basically the same result can be achieved, it is not necessary to follow the order of the steps in the process shown in FIG. 6 , and the steps shown in FIG. 6 do not have to be performed consecutively, that is, other steps can also be inserted therein. In addition, some steps in FIG. 6 may also be omitted according to different embodiments or design requirements. The detailed operation of step 402 may include the following steps:

Step 602: compare the audio playing time difference dRT _1AV with a critical value dRT _TH ;

Step 604: Determine whether the audio playback synchronization between the digital audio-visual media player 108 and the digital audio media player 110 is in a stable state? When the audio playback time difference dRT _1AV is less than the critical value dRT _TH , it is judged that the audio playback synchronization is in a stable state, and then step 606 is executed; and when the audio playback time difference dRT _1AV is not less than the critical value dRT _TH , it is judged that the audio playback synchronization is not stable state, then execute step 608;

Step 606: use at least one PLL unit 514 to generate a mismatch relative time position MRTP ₁ according to the audio playback time difference dRT _1AV ; and

Step 608 : Directly output the audio playback time difference dRT _1AV as the mismatch relative time position MRTP ₁ , and reset the phase locked loop unit PLL.

The judging unit 512 will execute steps 602 and 604 to judge whether the audio playback synchronization between the digital audio-visual media player 108 and the digital audio media player 110 is in a stable state, and the switching unit 516 selectively switches according to the output of the judging unit 1202 The output of the PLL unit 514 (step 606 ) or the output of the detection circuit 502 (step 608 ) is used as the mismatch relative time position MRTP ₁ . It should be noted that the synchronization stable state detected in steps 602 and 604 is used as a method for distinguishing between the following two ways of dealing with the audio playback time difference dRT _1AV . Generally speaking, at the beginning of the connection or due to poor signal The reconnection caused by the connection interruption caused by the situation will cause a large audio playback time difference dRT _1AV between the digital audio-visual media player 108 and the digital audio media player 110. In the case of normal connection and continuous transmission In this case, the audio playback time difference dRT _1AV usually changes little. Then, according to the above-mentioned judging mechanism, if it is in a stable synchronous state, the cause of the audio playback time difference dRT _1AV is mainly caused by the digital audio-visual media player 108 and the digital audio-visual media player 108 and the digital The frequency errors existing between the respective clock sources of the audio media player 110 will increase at a regular speed through the continuous accumulation of the audio playback time difference dRT _1AV . Although the speed is quite slow, it will still accumulate to the user over time. the degree to which it can be felt. Since the audio playback time difference dRT _1AV changes little under stable synchronization conditions, and irregular small changes caused by clock jitter and random noise or regular changes caused by frequency errors cannot be distinguished within a short period of time, it is necessary to The audio playback time difference dRT _1AV must be processed before it can be used, so as not to cause system instability. In this embodiment, the audio playback time difference dRT _1AV will be used as a phase error and input to the phase-locked loop unit 514 to track and lock digital audio-visual media playback The clock pulse of the device 108, that is, step 606. Conversely, if the synchronization is in an unsteady state, the audio playback time difference dRT _1AV is usually unpredictable and larger than that in a stable state, so immediate compensation is required. Therefore, in an unsteady state, the audio playback time difference dRT _1AV is directly output As a mismatch relative time position MRTP ₁ , and reset the PLL unit 514 , ie step 608 .

It should be noted that the technique for judging whether the audio playback synchronization of the digital audio-visual media player 108 and the digital audio media player 110 is in a steady state is not limited to the steps shown in FIG. 6 , and the critical value dRT _TH in step 602 can be It is set according to different environments or applications, and even the threshold value dRT _TH can be an adaptive variable value. And above-mentioned other designs also belong to the category of the present invention.

In addition, the single control circuit 504 can only handle a single audio playback time difference to control audio playback. Therefore, for the digital media controller 500 shown in FIG. 5, it is suitable for controlling a single digital audio-visual media player and a single digital audio media player. However, if there are M digital audio media players, the digital media controller 500 needs to be appropriately modified and simultaneously equipped with M corresponding control circuits to control the individual audio playback time differences dRT _1AV , dRT _2AV , . . . , dRT _MAV to correspondingly output mismatch relative time positions MRTP ₁ , MRTP ₂ , _.

In this embodiment, the digital media controller 104/500 will output the mismatch relative time position MRTP1 to the digital audio media player 110 to control the audio playback of the digital audio media player 110, in other words, based on the mismatch relative time position _MRTP1 , the audio playback of the digital audio media player 110 will be adjusted. Please refer to FIG. 7 . FIG. 7 is a flowchart of an embodiment of a method for controlling audio playback of the digital audio media player 110 according to the mismatch relative time position MRTP ₁ of the present invention. If basically the same result can be achieved, it is not necessary to follow the order of the steps in the flow shown in FIG. 7 , and the steps shown in FIG. 7 do not have to be performed consecutively, that is, other steps can also be inserted therein. In addition, some steps in FIG. 7 may be omitted according to different embodiments or design requirements. The operation of controlling the audio playback of the digital audio media player 110 may include the following steps:

Step 702: Convert the mismatched relative time position MRTP ₁ according to an audio packet length into a digital audio packet quantity V _P that needs to be adjusted and a remaining digital audio bit quantity V _B that is less than the audio packet length; and

Step 704: Control the audio playback of the digital audio media player 110 according to the number of digital audio packets V _P and the number of digital audio bits V _B.

Synchronizing the audio playback of the digital audio-visual media player 108 and the digital audio media player 110 is to make the two play the same audio position in the digital audio-visual data M _AV and digital audio data _MA at the same moment, in other words, in a stable playback And in a well-synchronized state, it must be ensured as much as possible that the two play the same bit in the same audio packet at every moment. Therefore, step 702 will first convert the mismatched relative time position MRTP ₁ into the number of digital audio packets V _P that needs to be adjusted and the remaining number of digital audio bits V _B that is less than the length of the audio packet, so as to facilitate processing according to two different units Synchronization control of digital audio media player 110. If the numerical values of the number of digital audio packets V _P and the number of digital audio bits V _B are not zero, then the number of digital audio packets V _P will affect the audio playback of the digital audio media player 110 in units of packets, and at the same time, the digital audio bits Quantity V _B can affect the audio frequency broadcasting of digital audio media player 110 with bit as unit; If the numerical value of digital audio packet quantity V _P is not zero, and the numerical value of digital audio bit quantity V _B is zero, then the numerical value of digital audio packet quantity _VP will affect the audio playback of the digital audio media player ₁₁₀ in units of packets _; V _B affects the audio playback of the digital audio media player 110 in units of bits.

In an implementation mode, the digital audio media player 110 will be responsible for generating the digital audio packet quantity VP and the digital audio bit quantity V _B (step 702), and the audio playback control of the digital audio media player 110 is through the digital audio media player 110 and the internal components of the digital media server 102 (step 704), in addition, in another implementation, the digital audio media player 110 will be responsible for generating the number of digital audio packets V _P and the number of digital audio bits V _B ( Step 702), and the audio playback control of the digital audio media player 110 is only realized through the internal components of the digital audio media player 110 itself (step 704). Further details will be detailed below.

Please refer to FIG. 8 and FIG. 9, FIG. 8 is a schematic diagram of a first embodiment of the digital audio media player 110 shown in FIG. 1, and FIG. 9 is a schematic diagram of an embodiment of the digital media server 102 shown in FIG. . Digital audio media player 110 can be implemented by digital audio media player 800, and digital media server 102 can be implemented by digital media server 900. In this embodiment, digital audio media player 800 includes an audio packet parser ( audio packet parser) 802, an audio packet decoder (audio packet PCM decoder) 804, an audio playback adjustment circuit (such as block PCM data shift controller (block PCM data shift controller)) 806, a control circuit 808 and a Relative to the time location storage (eg, memory) 810 , the digital media server 900 includes a packet processing circuit 902 and an audio playback adjustment circuit (eg, a packet skip module) 904 . The audio packet parser 802 receives a digital audio data input (such as digital audio data M _A provided by the digital media server 900), and sends the parsed packet to the audio packet decoder 804 to convert the packet into raw data (also That is, PCM data) is output to the audio playback adjustment circuit 806. On the other hand, the audio playback adjustment circuit 806 is controlled by the control circuit 808 so that the audio playback of the digital audio media player 800 is synchronized with the audio playback of the digital audio-visual media player 108. , wherein the control circuit 808 receives the mismatched relative time position MRTP ₁ from the digital media controller 104, and converts the mismatched relative time position MRTP ₁ into a digital audio packet quantity V _P that needs to be adjusted and the remaining deficiency according to an audio packet length A digital audio bit quantity V _B of the audio packet length, in this embodiment, the digital audio bit quantity V _B is input to the audio playback adjustment circuit 806, and the digital audio packet quantity VP is then input to the digital media server 900 to adjust it The audio package provided to the digital audio media player 800. In addition, the control circuit 808 also updates the audio playback relative time position RT ₁ of the digital audio media player 800 according to the mismatch relative time position MRTP ₁ .

For the digital media server 900, it can be used to provide a digital audio-visual data M _AV and a digital audio data _MA , wherein the packet processing circuit 902 is coupled to the audio playback adjustment circuit 904, and processes a digital audio-visual data D_IN into all After the required packet format, a data about digital audio is sent to the audio playback adjustment circuit 904, and the audio playback adjustment circuit 904 controls the digital audio data M according to the digital audio packet quantity VP output by the digital audio media player 800. _A , while the other digital audio-visual data M _AV can be directly output without adjustment. It should be noted that the audio playback adjustment circuit 904 can only control the output of digital audio data supplied to a digital audio media player, so the digital media server 900 shown in FIG. An example of an audio media player, if there are M digital audio media players, then the digital media server 900 needs to be properly modified to simultaneously match M corresponding audio playback adjustment circuits to separately control the M digital audio players. M digital audio data outputs for the media player.

In this embodiment, the audio playback adjustment circuit 904 located in the digital media server 900 can affect the audio playback of the digital audio media player 800 by skipping (skip) the audio packet (that is, speeding up the playback speed). The audio playback adjustment circuit 806 of the audio media player 800 can skip the audio data bits decoded by the audio packet decoder 804 (that is, speed up the playback) or add audio data bits with a value of 0 to the audio packet according to requirements. The decoder 804 decodes the resulting audio data bits (ie, slows down the playback speed) to affect the audio playback of the digital audio media player 800 .

As mentioned earlier, the mismatched relative time position MRTP ₁ is converted into the number of digital audio packets V _P and the number of digital audio bits V _B , i.e. using two components with different unit progressions to adjust the digital audio media player The 800 achieves two characteristics of fast synchronization and stable synchronization, in other words, uses a cores tune component and a fine tune component to control the audio playback of the digital audio media player 800 . The coarse adjustment component (i.e. the number of digital audio packets V _P ) is input to the digital media server 900 to adjust the playback position in units of packets, and the fine adjustment component (i.e. the number of digital audio bits V _B ) is input to the digital audio media player 800 to adjust the playback position in bits. However, when the digital media server 900 processes synchronization by skipping audio packets, the digital audio media player 800 can be temporarily in a silent state to avoid the user's awareness and feeling abrupt due to the change is more severe, and in a stable state, the digital audio media player 800 When the audio media player 800 adjusts the playback position in units of bits, it is usually not noticed by the user, so it is not necessary to put the digital audio media player 800 into a mute state.

Please refer to FIG. 10 . FIG. 10 is a flowchart of a first embodiment of a method for controlling audio playback of a digital audio media player according to the number of digital audio packets and the number of digital audio bits of the present invention. If basically the same result can be achieved, it is not necessary to follow the order of the steps in the flow shown in FIG. 10 , and the steps shown in FIG. 10 do not have to be performed consecutively, that is, other steps can also be inserted therein. In addition, some steps in FIG. 10 may also be omitted according to different embodiments or design requirements. The method for controlling the audio playback of a digital audio media player includes the following steps:

Step 1002: Control the digital media server according to the number of digital audio packets, so as to adjust the audio packets provided by the digital media server to the digital audio media player; and

Step 1004: Control at least one digital audio media player according to the number of digital audio bits, so as to adjust the audio data bits decoded by the digital audio media player.

Since those skilled in the art should easily understand the operation of each step in FIG. 10 after reading the above paragraphs, further descriptions are omitted here for brevity.

Please refer to FIG. 11 , which is a schematic diagram of a second embodiment of the digital audio media player 104 shown in FIG. 1 . The digital audio media player 104 can be implemented by the digital audio media player 1100 . In this embodiment, the digital audio media player 1100 includes the above-mentioned audio packet parser 802, audio packet decoder 804, control circuit 808 and relative time position storage 810, and also includes an audio adjustment circuit 1102, which includes There is a first audio playback adjustment unit (such as an audio packet skip controller) 1112 and a second audio playback adjustment unit (such as a block PCM data shift controller (block PCM data shift controller)) 1114. The number of digital audio packets VP and the number of digital audio bits VB converted by the control circuit 808 are used to respectively control the first audio playback adjustment unit 1112 and the second audio playback adjustment unit 1114 in the audio adjustment circuit 1102, so that the digital audio media player The audio playback of 1100 is synchronized with the audio playback of digital audiovisual media player 108 .

Please refer to FIG. 12 . FIG. 12 is a flow chart of a second embodiment of the method for controlling audio playback of a digital audio media player according to the number of digital audio packets and the number of digital audio bits of the present invention. If basically the same result can be achieved, it is not necessary to follow the order of the steps in the flow shown in FIG. 12 , and the steps shown in FIG. 12 do not have to be performed consecutively, that is, other steps can also be inserted therein. In addition, some steps in FIG. 12 may also be omitted according to different embodiments or design requirements. The method for controlling the audio playback of a digital audio media player includes the following steps:

Step 1202: Control the digital audio media player according to the number of audio packets _V to adjust the audio packets to be decoded in the digital audio media player; and

Step 1204: Control the digital audio media player according to the number of audio bits V _B to adjust the audio data bits decoded by the digital audio media player.

Since those skilled in the art can easily understand the operation of each step in FIG. 12 after reading the above paragraphs, further descriptions are omitted here for brevity.

Please note that the conversion of the mismatch relative time position MRTP ₁ into the number of digital audio packets V _P and the number of digital audio bits V _B is just one implementation of synchronization control and is not necessary. For example, when the mismatch When the value of the relative time position MRTP ₁ is not large, the mismatched relative time position MRTP ₁ can be directly used to control the audio playback of the digital audio media player. Please refer to FIG. 13 , which is a schematic diagram of a third embodiment of the digital audio media player 104 shown in FIG. 1 . The digital audio media player 104 can be implemented by the digital audio media player 1300 . In this embodiment, the digital audio media player 1300 includes the above-mentioned audio packet parser 802 , audio packet decoder 804 , audio playback adjustment circuit 806 and relative time position storage 810 , and also includes a control circuit 1302 . The control circuit 1302 directly outputs the mismatch relative time position MRTP1 to control the audio playback adjustment circuit 806 so that the audio playback of the digital audio media player 1300 is synchronized with the audio playback of the digital audio-visual media player 108 . This design change also belongs to the category of the present invention.

In the digital audio media player shown in Figures 8, 11, and 13, the control circuit 808/1302 will update the audio playback relative time position RT ₁ recorded in the relative time position storage 810 according to the mismatch relative time position MRTP ₁ , where the audio playback relative time position RT ₁ is the basis for calculating the audio playback time difference dRT _1AV , and the audio playback time difference dRT _1AV is the basis for calculating the mismatch relative time position MRTP ₁ , in other words, the audio playback relative time position RT ₁ is the basis for calculating No basis for matching relative time position MRTP ₁ . Therefore, when adjusting the digital audio media player according to the calculated mismatch relative time position MRTP ₁ , at the same time, the audio playback relative time position RT ₁ needs to be updated according to the adjusted amount, so as to avoid repeated compensation question.

The above descriptions are only preferred embodiments of the present invention, and all equivalent changes and modifications made according to the scope of the patent application of the present invention shall fall within the scope of the present invention.

Claims (24)

1. the method that the audio frequency of synchronous a plurality of digital media players is play, the plurality of digital media player comprises a digital audio-video media player and at least one digital audio players, and the method includes:

An audio frequency reproduction time of detecting between this digital audio-video media player and this at least one digital audio players is poor; And

According to the poor audio frequency of controlling this at least one digital audio players of this audio frequency reproduction time, play, so that the audio frequency of this at least one digital audio players is play the audio frequency broadcasting that is synchronized with this digital audio-video media player.

2. the method for claim 1, wherein the plurality of digital media player is from digital media server audio reception data, to carry out audio frequency broadcasting with wireless mode.

3. the method for claim 1, the poor step of this audio frequency reproduction time of wherein detecting between this digital audio-video media player and this at least one digital audio players comprises:

From this digital audio-video media player, receive an audio-visual broadcasting relative time position;

From this at least one digital audio players, receive an audio frequency and play relative time position; And

Calculating this audio-visual broadcasting relative time position and this audio frequency plays the mistiming of relative time position to be used as this audio frequency reproduction time poor.

4. the method for claim 1, the step of wherein playing according to the poor audio frequency of controlling this at least one digital audio players of this audio frequency reproduction time comprises:

According to this audio frequency reproduction time is poor, produces one and do not mate relative time position; And

According to this, not mating the audio frequency of controlling this at least one digital audio players in relative time position plays.

5. method as claimed in claim 4, wherein comprises according to poor this step of not mating relative time position that produces of this audio frequency reproduction time:

An audio frequency that judges this digital audio-video media player and this at least one digital audio players plays whether synchronize be steady state (SS);

If it is steady state (SS) that this audio frequency is play synchronously, at least with a phase-locked loop unit, according to the poor generation of this audio frequency reproduction time, this does not mate relative time position; And

If this audio frequency is play synchronous and unsteady state, directly export that this audio frequency reproduction time is poor to be used as this and not to mate relative time position, and this phase-locked loop unit of resetting.

6. method as claimed in claim 5, this audio frequency that wherein judges this digital audio-video media player and this at least one digital audio players is play and is synchronizeed that to be whether the step of steady state (SS) comprise:

Relatively this audio frequency reproduction time poor with a critical value;

When this audio frequency reproduction time is poor while being less than this critical value, judge that it is steady state (SS) that this audio frequency is play synchronous; And

When poor this critical value that is not less than of this audio frequency reproduction time, judge that it is not steady state (SS) that this audio frequency is play synchronous.

7. method as claimed in claim 4, wherein according to this, do not mate the step that the audio frequency of controlling this at least one digital audio players in relative time position plays and include:

According to an audio frequency package length, this is not mated to relative time position and be converted to a DAB package quantity of needs adjustment and a DAB amount of bits of this audio frequency package length of remaining deficiency; And

According to this DAB package quantity and this DAB amount of bits, controlling the audio frequency of this at least one digital audio players plays.

8. method as claimed in claim 7, wherein according to this DAB package quantity and this DAB amount of bits, control the step that the audio frequency of this at least one digital audio players plays and include:

According to this DAB package quantity, control a digital media server, to adjust this digital media server, provided the audio frequency package that gives this at least one digital audio players; And

According to this DAB amount of bits, control this at least one digital audio players, the voice data bit of being decoded and producing to adjust this at least one digital audio players.

9. method as claimed in claim 7, wherein according to this DAB package quantity and this DAB amount of bits, control the step that the audio frequency of this digital audio players plays and include:

According to this DAB package quantity, control this at least one digital audio players, to adjust audio frequency package to be decoded in this at least one digital audio players; And

According to this DAB amount of bits, control this at least one digital audio players, the voice data bit of being decoded and producing to adjust this at least one digital audio players.

10. method as claimed in claim 4, wherein according to this, do not mate the step that the audio frequency of controlling this at least one digital audio players in relative time position plays and include:

According to this, do not mate relative time position and control this at least one digital audio players, the voice data bit of being decoded and producing to adjust this at least one digital audio players.

11. methods as claimed in claim 4, the step of wherein not mating according to this audio frequency broadcasting of controlling this at least one digital audio players in relative time position also includes:

According to this, do not mate an audio frequency that upgrades this at least one digital audio players in relative time position and play relative time position.

12. 1 kinds of Digital Media controllers in order to synchronous a plurality of digital media players, the plurality of digital media player comprises a digital audio-video media player and at least one digital audio players ，Gai Digital Media controller includes:

One circuit for detecting, poor in order to an audio frequency reproduction time of detecting between this digital audio-video media player and this at least one digital audio players; And

One control circuit, be coupled to this circuit for detecting, in order to play according to the poor audio frequency of controlling this at least one digital audio players of this audio frequency reproduction time, so that the audio frequency of this at least one digital audio players is play the audio frequency broadcasting that is synchronized with this digital audio-video media player.

13. Digital Media as claimed in claim 12 controllers, wherein this circuit for detecting receives one first audio frequency from this digital audio-video media player and plays relative time position, from this at least one digital audio players, receive one second audio frequency and play relative time position, and calculating mistiming that this first, second audio frequency plays relative time position, to be used as this audio frequency reproduction time poor.

14. Digital Media as claimed in claim 12 controllers, wherein this control circuit produces one and does not mate relative time position according to this audio frequency reproduction time is poor, and according to this, does not mate the audio frequency of controlling this at least one digital audio players in relative time position and play.

15. Digital Media as claimed in claim 14 controllers, wherein this control circuit includes:

Whether one judging unit is steady state (SS) in order to judge that an audio frequency broadcasting of this digital audio-video media player and this at least one digital audio players is synchronizeed;

One phase-locked loop unit, in order to produce this and do not mate relative time position according to this audio frequency reproduction time is poor, wherein plays synchronously during not for steady state (SS) when this judging unit judges this audio frequency, and this phase-locked loop unit can be reset; And

One switch unit, be coupled to this judging unit and this phase-locked loop unit, being used to this judging unit judges when this audio frequency is play synchronously for steady state (SS), this that export that this phase-locked loop unit produces do not mate relative time position, and judge that in this judging unit this audio frequency plays synchronously during not for steady state (SS), directly export that this audio frequency reproduction time is poor to be used as this and not to mate relative time position.

16. Digital Media as claimed in claim 15 controllers, wherein this judging unit relatively this audio frequency reproduction time poor with a critical value; When this audio frequency reproduction time is poor while being less than this critical value, this judging unit judges that it is steady state (SS) that this audio frequency is play synchronous; And when poor this critical value that is not less than of this audio frequency reproduction time, this judging unit judges that it is not steady state (SS) that this audio frequency is play synchronous.

17. 1 kinds of digital audio players, include:

One audio frequency is play Circuit tuning; And

One control circuit, in order to Zi Yi Digital Media controller, receive one and do not mate relative time position, and according to this, do not mate relative time position and control this audio frequency and play Circuit tuning, so that the audio frequency of this digital audio players is play the audio frequency be synchronized with a digital audio-video media player, play, wherein this not mate relative time position be poor corresponding to the audio frequency reproduction time between this digital audio players and this digital audio-video media player.

18. digital audio players as claimed in claim 17, wherein this digital audio players is from digital media server audio reception data, to carry out audio frequency broadcasting with wireless mode.

19. digital audio players as claimed in claim 17, wherein this control circuit does not mate relative time position according to an audio frequency package length by this and is converted to a DAB package quantity that needs adjust and a DAB amount of bits of this audio frequency package length of remaining deficiency, and the audio frequency broadcasting of controlling this at least one digital audio players according to this DAB package quantity and this DAB amount of bits.

20. digital audio players as claimed in claim 19, wherein this control circuit is exported this DAB package quantity to one digital media server and is adjusted this digital media server the audio frequency package that gives this digital audio players is provided, and exports this DAB amount of bits to this audio frequency and play Circuit tuning; And this audio frequency broadcasting Circuit tuning adjusts according to this DAB amount of bits the voice data bit that this digital audio players is decoded and produced.

21. digital audio players as claimed in claim 19, wherein this control circuit is exported this DAB package quantity and this DAB amount of bits to this audio frequency and is play Circuit tuning; And this audio frequency plays Circuit tuning and adjust audio frequency package to be decoded in this digital audio players according to this DAB package quantity, and adjust the decode voice data bit of generation of this digital audio players according to this DAB amount of bits.

22. digital audio players as claimed in claim 17, wherein this control circuit does not mate relative time position according to this and controls this audio frequency and play Circuit tuning, to adjust audio frequency package to be decoded in this digital audio players and to adjust the decoded voice data bit of generation of this digital audio players.

23. digital audio players as claimed in claim 17, wherein this control circuit does not mate relative time position according to this and controls this audio frequency and play Circuit tuning, to adjust the decoded voice data bit of generation of this digital audio players.

24. digital audio players as claimed in claim 17, wherein this control circuit does not separately mate according to this audio frequency broadcasting relative time position that this digital audio players is upgraded in relative time position.

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