EP3220660A1

EP3220660A1 - Method adapted to be performed in a master device of a sound system, corresponding configuring methods for an audio rendering device, corresponding devices, system, computer readable program products, computer readable storage media and signal

Info

Publication number: EP3220660A1
Application number: EP16305287.1A
Authority: EP
Inventors: Ludovic Jeanne; Jean-Pierre Bertin; Anne Peaudouye
Original assignee: Thomson Licensing SAS
Current assignee: Thomson Licensing SAS
Priority date: 2016-03-16
Filing date: 2016-03-16
Publication date: 2017-09-20

Abstract

The present disclosure relates to a method, adapted to be performed at a master device of a distributed sound system belonging to a communication network, the master device being adapted to output at least one audio channel to at least one audio rendering device of said sound system.

According to an embodiment of the present disclosure, the method comprises:
- obtaining one information representative of a connection, to said sound system, of an audio rendering device being of a first type of audio rendering devices;
- sending to one audio rendering device of said sound system an indication of presence of a connected audio rendering device of the first type in said sound system.

The present disclosure also relates to corresponding configuring methods, adapted to be performed in an audio rendering device, and to the corresponding master device, audio rendering devices, system, computer readable program products, computer readable storage media and signal.

Description

1. Technical field

The present disclosure relates to the field of audio rendering in a distributed system including at least one audio rendering device.
A method adapted to be performed in a master device of a sound system, corresponding configuring methods for an audio rendering device, corresponding devices, system, computer readable program products, computer readable storage media and signal are described.

2. Background art

Communication end-devices, for instance set-top-box (STB), smartphones, tablets, personal computers or peripherals like printers, speakers (or audio renderers), microphone have become widely used nowadays. They can exchange data with other communication devices inside a communication network, for instance a local area network (LAN) thanks to wired communication interfaces (like Ethernet interface) or wireless communication interfaces, like WIFI® or Bluetooth® interfaces. More and more LAN services, notably WLAN services, are deployed in a home environment and used for day-to-day life. The use of wireless devices in a network prevents the need, for a user, from cabling or physically interconnecting devices. However, configuration can still be necessary. Notably, a system (like an audio and/or video system of a home network) comprising several communication devices can have multiple configurations, depending upon the number and the kind of devices present in the system. Notably, an audio surround system can comprise different kind of audio renderers. Indeed, a kind of audio renderer (also called subwoofer) can be dedicated to the rendering of low frequency part of an audio signal (like part of the audio signal having a frequency between 16 to 256 Hz). Another kind of audio renderers, like medium speaker or satellite speaker, can be configured in at least two audio rendering mode: one audio rendering mode is a high pass filter mode, another audio rendering mode is a bass booster mode. In the high pass filter mode, a satellite speaker only renders the high frequency part of an audio signal received. This mode is particularly adapted to configurations of audio system also comprising a subwoofer that renders the bass component of a received audio signal.
In the bass booster mode, a satellite speaker further renders the bass part of the audio signal received. This mode is particularly adapted to configurations of audio system without any subwoofer.
some solutions of the prior art have tried to prevent a user from defining manually the audio rendering mode of its satellite speaker by providing an audio master device that outputs to the speaker only the adequate part of the audio signal, depending on the presence or not of a subwoofer.

3. Summary

The present principles enable at least one of the above disadvantages to be resolved by proposing a method adapted to be performed at a master device of a distributed sound system belonging to a communication network, said master device being adapted to output at least one audio channel to at least one audio rendering device of said sound system. According to an embodiment of the present disclosure, the method comprises:

obtaining at least one information representative of a connection, to said sound system, of an audio rendering device being of a first type of audio rendering devices;
sending to at least one audio rendering device of said sound system an indication of presence of a connected audio rendering device of said first type in said sound system.

It is to be noted that, in at least some embodiment, the received representative information can be not only adapted to inform the master device of the connection to the sound system of a device (which can be a first type or not) but can be adapted to inform the master device that at least one audio rendering device being of the first type has been connected to the sound system. For instance, in some embodiments where the first type represents subwoofer audio rendering devices, the received representative information can be not only adapted to inform the master device of the connection to the sound system of a device (which can be a subwoofer or not) but can be adapted to inform the master device that at least one subwoofer has been connected to the sound system. In some embodiments, the representative information is further adapted to inform the master device that the sender of the representative information is itself an audio rendering device of a first type (for instance a subwoofer) or to identity the newly connected audio rendering device of the first type.
According to an embodiment of the present disclosure, said sending is performed for each obtaining.
According to an embodiment of the present disclosure, said sending to at least one audio rendering device of said sound system is performed to each audio rendering device of said first type and/or of a second type connected to said sound system.
According to an embodiment of the present disclosure, said sending to at least one audio rendering device of said sound system is performed when no audio rendering device of said first type was connected to said sound system before said obtaining.
According to an embodiment of the present disclosure, said first and/or said second type of audio rendering device represents a rendering device belonging to a group comprising:

a subwoofer;
a medium speaker;
a tweeter speaker;
a satellite speaker;
a combination thereof.

According to an embodiment of the present disclosure, said obtaining comprises receiving said representative information from said communication network.
According to an embodiment of the present disclosure, said method comprises:

detecting a disconnection of an audio rendering device of said first type to said sound system;
sending to at least one audio rendering device of said sound system an indication of absence of a connected audio rendering device of said first type in said sound system.

According to an embodiment of the present disclosure, said sending of said indicating of absence is performed for each detected disconnection.
According to an embodiment of the present disclosure, said sending to at least one audio rendering device of said sound system is performed to each audio rendering device of said first type and/or of a second type connected to said sound system.
According to an embodiment of the present disclosure, said sending is performed only when no audio rendering device of said first type is connected to said sound system after said disconnection.
According to an embodiment of the present disclosure, said method comprises, at a time of a connection of an audio rendering device to said sound system, sending to said newly connected audio rendering device an indication of presence and/or absence, before said connection, of at least one already connected audio rendering device of said first type in said sound system.
According to an embodiment of the present disclosure, said obtaining and/or said detecting comprises storing at least one datum indicative of said connection and/or disconnection of an audio rendering device of said first type, and said sending at the time of said connection of said newly connected audio rendering device comprises accessing said stored datum.
According to another aspect, the present disclosure relates to a master device of a distributed sound system belonging to a communication network, said master device being adapted to output at least one audio channel to at least one audio rendering device of said sound system and comprising at least one processor.
According to an embodiment of the present disclosure, said processor is configured for:

According to another aspect, the present disclosure relates to a master device of a distributed sound system belonging to a communication network, said master device being adapted to output at least one audio channel to at least one audio rendering device of said sound system.
According to an embodiment of the present disclosure, said master device comprises at least one memory and at least one processing circuitry configured to perform:

While not explicitly described, a master device of the present disclosure can be adapted to perform the corresponding method of the present disclosure in any of its embodiments.
According to another aspect, the present disclosure relates to a configuring method, adapted to be performed at an audio rendering device at a time of a connection of said audio rendering device to a distributed sound system belonging to a communication network.
According to an embodiment of the present disclosure, said method comprises sending to a master device of said sound system an information representative of a type of audio rendering devices to which said audio rendering device belongs to.
According to an embodiment of the present disclosure, said first and/or said second type of audio rendering devices represents a rendering device belonging to a group comprising:

According to another aspect, the present disclosure relates to an audio rendering device adapted to be connected to a distributed sound system belonging to a communication network, said audio rendering device comprising at least one processor.
According to an embodiment of the present disclosure, said processor is configured for sending to a master device of said sound system, at a time of a connection of said audio rendering device to said distributed sound system, an information representative of a type of audio rendering devices to which said audio rendering device belongs to.
According to another aspect, the present disclosure relates to an audio rendering device adapted to be connected to a distributed sound system belonging to a communication network.
According to an embodiment of the present disclosure, said audio rendering device comprises at least one memory and at least one processing circuitry configured to perform sending to a master device of said sound system, at a time of a connection of said audio rendering device to said distributed sound system, an information representative of a type of audio rendering devices to which said audio rendering device belongs to.
According to another aspect, the present disclosure relates to a configuring method, adapted to be performed at an audio rendering device of a distributed sound system belonging to a communication network, for setting an audio rendering mode of said audio rendering device.
According to an embodiment of the present disclosure, said setting is performed according to at least one information received from a master device of said distributed sound system.
According to an embodiment of the present disclosure, said information is representative of a presence and/or an absence of a connected audio rendering device of a first type in said distributed sound system.
According to an embodiment of the present disclosure, said method is adapted to be performed at an audio rendering device of a second type.
According to an embodiment of the present disclosure, said audio rendering mode belongs to a group comprising:

a high pass filter mode;
a bass booster mode;
an "offset phase" mode, where an offset is applied to the phase of an audio signal to be rendered;
an "no phase offset" mode, where no offset need to be applied to the phase of an audio signal to be rendered;
a "limited volume" mode, where the audio rendering device limits the volume of an rendered audio signal to a given value;
a "no volume limitation" mode, where no limitation of the volume of an rendered audio signal is needed;
a "frequency range adaptation" mode, where the audio rendering device adapts the low and/or high frequency cut for an audio signal to be rendered;
a "unchanged frequency range mode, where the audio rendering device keep its own low and high frequency cut for an audio signal to be rendered;
a combination thereof.

According to another aspect, the present disclosure relates to an audio rendering device adapted to be connected to a distributed sound system belonging to a communication network, said audio rendering device comprising at least one processor.
According to an embodiment of the present disclosure, said processor is configured for setting an audio rendering mode of said audio rendering device, wherein said setting is performed according to at least one information received from a master device of said sound system.
According to another aspect, the present disclosure relates to an audio rendering device adapted to be connected to a distributed sound system belonging to a communication network.
According to an embodiment of the present disclosure, said audio rendering device comprises at least one memory and at least one processing circuitry configured to perform setting an audio rendering mode of said audio rendering device, wherein said setting is performed according to at least one information received from a master device of said sound system.
According to an embodiment of the present disclosure, said information is representative of a presence and/or an absence of an audio rendering device of a first type in said distributed sound system.
According to an embodiment of the present disclosure, said audio rendering device comprises a digital processing unit.
According to an embodiment of the present disclosure, said audio rendering device comprises a power amplifier.
While not explicitly described, an audio rendering device of the present disclosure can be adapted to perform the corresponding configuring method of the present disclosure in any of its embodiments.
According to another aspect, the present disclosure relates to a distributed sound system belonging to a communication network and comprising a least one master device, said master device being adapted to output at least one audio channel to at least one audio rendering device of said sound system.
According to an embodiment of the present disclosure, said master device comprises at least one processor configured for:

obtaining at least one information representative of a connection, to said sound system, of a first audio rendering device, said first audio rendering device being of a first type of audio rendering devices;
sending to at least one second audio rendering device of said sound system an indication of presence of a connected audio rendering device of said first type in said sound system; and

According to an embodiment of the present disclosure, said master device comprises at least one memory and at least one processing circuitry configured to perform:

obtaining at least one information representative of a connection, to said sound system, of an audio rendering device being of a first type of audio rendering devices;
sending to at least one audio rendering device of said sound system an indication of presence of a connected audio rendering device of said first type in said sound system; and said audio rendering device comprises at least one memory and at least one processing circuitry configured to perform a setting of an audio rendering mode of said second audio rendering device, said setting being performed according to said indication sent by said master device.

While not explicitly described, the at least one audio rendering device and the master device of the system of the present disclosure can be adapted to perform the corresponding methods of the present disclosure in any of theirs embodiments.
While not explicitly described, the present embodiments related to a method or to the corresponding master device, audio rendering device or system can be employed in any combination or sub-combination. For example, some embodiments of a method, adapted to be performed in a master device of a distributed sound system belonging to a communication network, can involve:

obtaining at least one information representative of a connection, to said sound system, of an audio rendering device being of subwoofer type;
sending to at least one audio satellite speaker of said sound system an indication of presence of a connected audio rendering device of subwoofer type in said sound system, said sending being performed when no audio rendering device of subwoofer type was connected to said sound system before said obtaining.

According to another aspect, the present disclosure relates to a non-transitory program storage product, readable by a computer.
According to an embodiment of the present disclosure, said non-transitory computer readable program product tangibly embodies a program of instructions executable by a computer to perform at least one of the methods of the present disclosure in any of its embodiments.
According to an embodiment of the present disclosure, said non-transitory computer readable program product tangibly embodies a program of instructions executable by a computer for performing, when said non-transitory software program is executed by a computer, a method adapted to be performed at a master device of a distributed sound system belonging to a communication network comprising:

According to an embodiment of the present disclosure, said non-transitory computer readable program product tangibly embodies a program of instructions executable by a computer for performing, when said non-transitory software program is executed by a computer, a configuring method, adapted to be performed at an audio rendering device at a time of a connection of said audio rendering device to a distributed sound system belonging to a communication network, said method comprising sending to a master device of said sound system an information representative of a type of audio rendering devices to which said audio rendering device belongs to.
According to an embodiment of the present disclosure, said non-transitory computer readable program product tangibly embodies a program of instructions executable by a computer for performing, when said non-transitory software program is executed by a computer, a configuring method, adapted to be performed at an audio rendering device of a distributed sound system belonging to a communication network, for setting an audio rendering mode of said audio rendering device, wherein said setting is performed according to at least one information received from a master device of said distributed sound system.
According to another aspect, the present disclosure relates to a computer readable storage medium carrying a software program comprising program code instructions for performing at least one of the methods of the present disclosure, in any of its embodiments, when said non transitory software program is executed by a computer.
According to an embodiment of the present disclosure, said computer readable storage medium tangibly embodies a program of instructions executable by a computer for performing, when said non-transitory software program is executed by a computer, a method, adapted to be performed at a master device of a distributed sound system belonging to a communication network comprising:

According to an embodiment of the present disclosure, said computer readable storage medium tangibly embodies a program of instructions executable by a computer for performing, when said non-transitory software program is executed by a computer, a configuring method, adapted to be performed at an audio rendering device at a time of a connection of said audio rendering device to a distributed sound system belonging to a communication network, said method comprising sending to a master device of said sound system an information representative of a type of audio rendering devices to which said audio rendering device belongs to.
According to an embodiment of the present disclosure, said computer readable storage medium tangibly embodies a program of instructions executable by a computer for performing, when said non-transitory software program is executed by a computer, a configuring method, adapted to be performed at an audio rendering device of a distributed sound system belonging to a communication network, for setting an audio rendering mode of said audio rendering device, wherein said setting is performed according to at least one information received from a master device of said distributed sound system.
According to another aspect, the present disclosure relates to an electronic signal exchanged between a master device and at least one audio rendering device of a distributed sound system belonging to a communication network.
According to an embodiment of the present disclosure, said electronic signal comprises an information representative of a presence of a connected audio rendering device of a first type to said sound system.

4. List of drawings.

The present disclosure can be better understood, and other specific features and advantages can emerge upon reading the following description, the description making reference to the annexed drawings wherein:

Figure 1 shows an example of a sound system belonging to a wireless communication network according to a particular embodiment of the present disclosure;
Figures 2A and 2B show exemplary configurations of the sound system of figure 1;
Figure 3 illustrates an exemplary structure of an audio renderer of the sound system of figure 1;
Figure 4 illustrates an embodiment of the method of the present disclosure performed in a master device of the sound system of figure 1;
Figure 5 illustrates an exemplary structure of the master device of the sound system of figure 1;
Figure 6 illustrates an embodiment of the method of the present disclosure performed in an audio rendering of the sound system of figure 1.

It is to be noted that the drawings have only an illustration purpose and that the embodiments of the present disclosure are not limited to the illustrated embodiments.

5. Detailed description of the embodiments.

At least one embodiment of the present disclosure offers a new way of setting up an audio configuration of at least one audio rendering device (like an audio renderer of type subwoofer or satellite speaker) of a sound system comprising a master device (for instance a STB, a TV, a tablet, a smartphone or a PC) and belonging to a communication network (like a local area network).
Indeed, at least some embodiments of the present disclosure allow to have an at least partially automatic setup of the audio rendering mode of an audio rendering device (for instance a satellite speaker, a medium speaker, a tweeter speaker or a subwoofer) while reducing the complexity and/or the hardware manufacturing cost of the audio rendering device. This is achieved thanks to an at least partially automatic audio configuration of an audio rendering device (like a satellite speaker, a medium speaker, a tweeter speaker or a subwoofer) thanks to an exchange with the master device.
More precisely, at least one embodiment of the present disclosure proposes a configuration process of an audio rendering device that adapts (at least partially) automatically the audio rendering mode of this rendering device according to the capabilities of the others audio rendering device present and enabled in the system.
At least one embodiment of the present disclosure can thus permit to suppress, or at least limit, the need of dedicated user switches (like mechanical switches) on the audio rendering devices or an implementation of a complicated method in a firmware of a master device and permits a dynamic audio rendering adaptation that follows the network changes (typically when a subwoofer is connected or not to the sound system).
At least some embodiments of the present disclosure can be adapted to a configuration of a wireless system comprising a variable number of devices.
Moreover, in at least some embodiments, a single firmware of an audio rendering device can be developed, that can be embedded in different kinds of renderer devices (like in a satellite speaker and in a subwoofer).
In the detailed embodiment illustrated in figure 1, a sound system 100 is described. The sound system can further comprise video processing capabilities.
The sound system 100 belongs to a communication network 110, for instance a wireless communication network. The system 100 is a distributed sound system (for instance a surround sound system) that notably includes a master device 120, acting as a routing device, adapted to output at least an audio signal. Depending upon embodiments, the master device can be a Set Top Box, a tablet, a PC, a smartphone, a Blue-ray player, a TV, or any kind of wireless device that can output audio channels. In the illustrated embodiment, this master device is a Set Top Box (STB) 120 which can receive an audiovisual signal (for instance from another communication network, like an internet network) and can output a video component of the audiovisual signal (that can be rendered by a display 130 for instance) and at least one audio component of the audiovisual signal (that can be rendered by an audio renderer 140, 142, 144, 146, 150 of the system 100 for instance). In the particular embodiment of figure 1, the STB 120 is equipped with a peripheral device 122, for instance a dongle connected to one of the USB port of the STB, comprising wireless transmitting means adapted for output the audio channels. The dongle 122 can optionally comprise wireless receiving means.
The system 100 also include audio renderers 140, 142, 144, 146, 150, acting as slave devices of the master device 120. In the illustrated embodiment, the audio renderers are either satellite loudspeakers 140, 142, 144, 146 or a subwoofer 150. A subwoofer is a specialized audio renderer, in charge of the rendering of the low frequency part of an audio signal thanks to a low pass filter.
At least one of the audio renderers 140, 142, 144, 146, 150 of the system implements a configuring method 600 of the present disclosure. In the illustrated embodiment of figure 1, every renderer of the system implements the method of the present disclosure. However, in other embodiments, the method 400 and the configuring method 600 of the present disclosure can be implemented respectively in a master device and in an audio renderer being part of a system also comprising other devices not implementing the configuring methods of the present disclosure, or a different embodiment of the configuring methods of the present disclosure.
In some other embodiment, other types of audio rendering devices (like a medium speaker or a tweeter speaker) working in different frequency ranges can be present in the sound system. For instance a medium speaker can work in frequencies between 100 to 4000 Hz, a tweeter speaker can work in frequencies above 4000 Hz. A satellite speaker can comprise a combination of at least one medium speaker and at least one tweeter speaker.
In the embodiment illustrated, all the devices are wireless devices. Of course, the present disclosure is not limited to wireless system. In other embodiments, the communication network can be an Internet Protocol (IP) based network and the system can also comprise wired devices, like devices connected via an Ethernet connection. Other types of wired connections can be used, if they are adapted to permit the respect of audio synchronization constraints between the wireless and wired part of the distributed sound system. For instance, the display or the subwoofer can be connected by an Ethernet wired connection to the STB.
In this illustrated embodiment, the protocol to be used to exchange data between the renderer devices and the master device 120 is a specific protocol, for instance a protocol used by the product TI CC85xx developed by Texas Instrument ®). Different types of protocols can be used, depending upon embodiments.
Figure 7 illustrates an exemplary structure of a message exchanged inside the sound system of figure 1 between an audio renderer device, acting as a slave device, and the master device. In the illustrated embodiment, a message can be transmitted from a slave to the master, or from the master to a slave. As illustrated a message can comprise the following fields:

a field "Destination" 710 (coded on 4 bytes in the detailed embodiment), representing an address of a destination device (DevID) of the message. A specific value (like "0xFFFFFFFF" can be used for a broadcast of a message). If a unicast address is used, the message is to be sent to the device which address is comprised in the field "Dest add"). In the case of a message originating from a slave device, a value "0xFFFFFFFF" of the destination field can be interpreted by the master device as a message to be forwarded by broadcast by the master device. Similarly, a unicast address, different from the master device, of the destination field can be interpreted by the master device as a message to be forwarded to this unicast address by the master device;
a field "Source" 720 (coded on 4 bytes in the detailed embodiment), representing an address of a source device (DevID) of the message, or in other word the device from which the message is originating;
a field "Command" 730 , that can be used for identification of a command (coded on 1 byte in the detailed embodiment), or a transmission of a given information;
a data field 740 (coded on 0 to 23 bytes in the detailed embodiment) that can be used to transmit any type of data or can be left empty.

The data field can be used for instance for the transmission of an identifier of an audio rendering device, of an indication related to a type of an audio rendering device and/or to an audio rendering characteristic of the audio rendering device. For instance, in embodiments where the system can comprise at least two subwoofers, the data field can comprise an indication about the phasing of the audio signals rendered by a subwoofer. In another embodiment, it can comprise an indication related to a frequency range and/or a volume range of an audio rendering device. Of course, in some embodiments, the data field can comprise several indications.
In a variant, in embodiments where several indications are to be transmitted, they can be transmit in several messages by the audio rendering device.
Depending upon embodiments, the renderers can have different or similar acoustic characteristics. In a simplification purpose, in the illustrated embodiment of figure 1, all the satellite speakers have the same acoustic characteristics, and the same firmware. Of course, in other embodiments, the system can comprise a heterogeneous set of satellite speakers, with different firmware, or different kinds of speakers.
In the system 100, the audio renderers present at a given moment in the system can vary. For instance, a renderer can be either on or off. An audio renderer can also be added or removed from the system by a user.
Figures 2A and 2B illustrate different wireless audio configurations of the system 100.
In the example illustrated by figure 2A, the configuration is of type "2.1". The system 100 can comprise the display (herein a TV set) 130, the STB 120, and two mono channel satellite speakers (a front left satellite speaker with high pass filter and a front right satellite speaker with high pass filter) and a subwoofer comprising a front left and a front right audio output with a low pass filter. The wireless subwoofer is present and enabled.
In the example illustrated by figure 2B, the configuration is of type "2.0". The system can comprise the same devices as in the example of figure 2A, except that the subwoofer is either absent or disabled.
Some speakers, like the satellite speaker of figure 1, can be configured in at least two audio rendering modes: one audio rendering mode is a high pass filter mode, another one audio rendering mode is a bass booster mode.
In high pass filter mode, the speaker can only render the high frequency part of an audio signal received. In bass booster mode, the speaker can also render the bass part of the audio signal received.
In the illustrated embodiment, each satellite speaker has to select an appropriate rendering mode:

a "high pass filter" rendering mode when a subwoofer 150 is connected to the sound system 100;
a "bass booster" rendering mode when the subwoofer is not present or disabled.

Indeed, when the low frequency rendering is already taken in charge by the subwoofer, the satellite speaker should eliminate the low frequency part of the received audio signal. At the opposite, when no subwoofer is present, the speaker should also consider the low frequency part of the received audio signal.
In other embodiment, an audio rendering device can be configured in different audio rendering modes, being for instance a mode being a combination of a "frequency range adaptation" mode and a "limited volume" mode, with a modified low and/or high frequency cut of the audio rendering device and a limitation of a volume of a rendered audio signal to a given value.
In other embodiment where several subwoofers are present in a sound system, one subwoofer can be configured (in an "offset phase" mode) to offset the phase of an audio signal to be rendered, in order to render an audio signal having a phase being different to a phase of an audio signal rendered by the other subwoofer. For example, in embodiments where two subwoofers are present, a subwoofer can be configured to work in an opposite phase, compared to the other subwoofer.
Figure 3 describes the structure of a wireless audio renderer adapted to implement the method 600 of the present disclosure. It can be for instance a wireless renderer illustrated by figure 1, like a satellite speaker 140, 142, 144, 146 or a subwoofer 150.
In the particular embodiment of figure 3, the audio renderer can include different devices, linked together via a data and address bus 300, which can also carry a timer signal. For instance, it can include a micro-processor 31 (or CPU), at least one Input/ Output module 34, (like a tactile display, a switch, a led, a button, and so on), a ROM (or « Read Only Memory ») 35, a RAM (or « Random Access Memory ») 36, communication interfaces 371, 372 configured for the reception and/or transmission of data via a wireless connection, wired communication interfaces 38 (optional), a power supply 39.
The audio renderer can also include diverse audio rendering means. For instance, it can include at least one audio amplifier, at least one high pass filter, at least one bass booster, at least one low pass filter, at least one equalizer, at least one generator of psycho-acoustic effects, at least one audio compressor, or/and at least one mixer.
In the illustrated embodiment, the audio renderer 140, 142, 144, 146, 150 can communicate with the master device 120 (linked to a display 130 as illustrated by figure 1) thanks to a wireless interface.
Each of the mentioned memories can include at least one register, that is to say a memory zone of low capacity (a few binary data) or high capacity (with a capability of storage of a whole program or of all or part of data representative of data to be calculated or displayed).
When the audio renderer is powered on, the microprocessor 31 loads the program instructions 360 in a register of the RAM 36, notably the processes needed for performing at least one embodiment of the configuring method described herein, and executes the program instructions.
According to a variant, the audio renderer includes several microprocessors.
According to another variant, the power supply 39 is external to the audio renderer.
The audio renderer can notably belong to a sound system further comprising at least one master device. The sound system can also comprise at least another audio renderer, as illustrated by figures 1 and 2A to 2B.
In the particular embodiment illustrated in figure 3A, the microprocessor 31 can be configured for:

sending to a master device of the sound system, at a time of a connection of the audio rendering device to the distributed sound system, an information representative of a type of audio rendering devices to which the audio rendering device belongs to; and/or
setting an audio rendering mode of the audio rendering device, wherein the setting is performed according to at least one information received from a master device of the sound system.

Figure 5 describes a master device, like a STB equipped or not with a dedicated dongle as the master device 120 illustrated by figure 1.
In the particular embodiment of figure 5, the master device can include different devices, linked together via an USB protocol or via a data and address bus 500 which can also carry a timer signal. For instance, it can include a micro-processor 51 (or CPU), at least one Input/ Output module 54, (like a tactile display, a switch, a led, a button, and so on), a ROM (or « Read Only Memory ») 55, a RAM (or « Random Access Memory ») 56, communication interfaces 571, 572 configured for the reception and/or transmission of data via a wireless connection, wired communication interfaces 58 (optional), a power supply 59. The master device can also comprise other wireless connections, like WIFI or Bluetooth® connections (optional).
In some embodiments, the master device can also include, or be connected to, a display module 504, for instance a screen or the TV set 130, directly connected to a graphics card 52 by a dedicated bus 50. This elements are optional.
In the illustrated embodiment, the master device is adapted to output at least one audio channel to at least one audio rendering device 140, 142, 144, 146, 150 of the sound system 100 thanks to a wireless interface.
Each of the mentioned memories can include at least one register, that is to say a memory zone of low capacity (a few binary data) or high capacity (with a capability of storage of a whole program or of all or part of data representative of data to be calculated or displayed).
When the master device is powered on, the microprocessor 51 loads program instructions 560 in a register of the RAM 56, notably the processes needed for performing at least one embodiment of the method performed in a master device described herein, and executes the program instructions.
In the particular embodiment illustrated in figure 5, the microprocessor 51 can be configured for:

obtaining at least one information representative of a connection, to the sound system, of an audio rendering device being of a first type of audio rendering devices;
sending to at least one audio rendering device of the sound system an indication of presence of a connected audio rendering device of the first type in the sound system. According to a variant, the master device includes several microprocessors. According to another variant, the power supply 59 is external to the master device.

Figure 4 shows a particular embodiment of the method 400 of the present disclosure, implemented in a master device. For instance, the master device can be a STB 120, or a specific dongle 122 connected to a legacy STB 120 and embedding a microcontroller implementing the method of the present disclosure, as illustrated by figure 1.
According to the embodiment described by figure 4, where the devices can communicate with a protocol requiring a pairing between a master device and a slave device, the user of the system of figure 1 has already switched on the master device (herein a STB).
According to the embodiment illustrated, the method 400 can comprise tracking 410 the presence (or absence) of a subwoofer in the audio wireless network.
It is to be noted that in other embodiments, the tracking 400 can relate to at least one other type of audio rendering devices of the sound system.
After a subwoofer is switched on, the method 400 can comprise obtaining 411 an information, from the subwoofer, representative of its connection to the audio wireless network. In the embodiment described, where the master device and the subwoofer are wireless devices implementing the methods of the present disclosure, the obtaining 411 can comprise receiving the information, from the subwoofer, thanks to the communication network. In other embodiments, where the master device and the subwoofer are linked by a wired connection, or where the subwoofer do not implement the configuring methods of the present disclosure, the obtaining can be performed thanks to a user interface (for instance a dedicated switch).
With the exemplary structure of message illustrated by Figure 7, the master device can for instance receive a message with:

field "Destination" 710 having the value "0xFFFFFFFF" (for broadcast) or the address of the master device;
field "Source" 720 having the value of the subwoofer device address in the communication network;
field "Command" 730 having the value "0xF1" representative of a subwoofer presence
No data field included.

In embodiments where the system can comprise at least two subwoofers, the data field can comprise an indication about the phasing of the audio signals rendered by the subwoofer.
In an embodiment where the destination field of the received message has the value dedicated to "broadcast", the master device can retransmit the received message to all slaves present without having knowledge of the content of the field "command".
In a variant, the master device can analyze the "command" field of a message and retransmit the message when it contains a value representative of a presence of a subwoofer.
Such embodiments can thus be adapted to a use of a legacy set top box, equipped with a specific peripheral device, for instance as specific dongle taking in charge the acoustic configuration of the system, with audio renderers implemented the configuring method 600 illustrated by figure 6 of the present disclosure.
In the illustrated embodiment, the method can comprise 412 storing at least one datum related to the presence of a subwoofer in a memory (for instance a flash memory) of the master device.
The method can also comprise sending 413 to all the satellite speakers present in the system a message indicative of the presence of the subwoofer. Depending upon embodiments, the sending can be performed by means of unicast messages (to each satellite speakers present) of by means of a multicast message broadcasted in the sound system. Depending embodiments, the sending can comprise sending the message to all audio rendering devices of the system, or to least a type of audio rendering device. For instance, in embodiments adapted to sound system that can comprise at least two subwoofers, the sending can comprise sending the message to at least one audio rendering device of subwoofer type (for instance, a subwoofer different from the one just being connected to the system).
With the exemplary structure of message illustrated by Figure 7, the master device can for instance send a message with:

field "Destination" 710 having the value "0xFFFFFFFF" (for broadcast);
field "Source" 720 having the value of the master device address in the communication network;
field "Command" 730 having the value "0xF1" representative of a subwoofer presence
No data field included.

In embodiments where the system can comprise at least two subwoofers, the data field can comprise an indication about the phasing of the audio signals rendered by the subwoofer.
In a variant, in embodiments where a received message contains several indications, the master device can transmit several messages (one per indication for instance) to the audio rendering devices.
In the illustrated embodiment, if the subwoofer is disconnected from the network, the method further can comprise detecting 414 the disconnection of the subwoofer (using its transport protocol for instance), updating 415 the at least one datum related to the presence of the subwoofer in the memory of the master device, in order to reflect the absence of the subwoofer, and transmitting 416 a message indicative of an absence of subwoofer to all the connected speakers. Depending upon embodiments, the transmitting 416 can be performed by means of unicast messages (to each satellite speakers present) of by means of a multicast message broadcasted in the sound system.
With the exemplary structure of message illustrated by Figure xx, the master device can for instance send a message with:

field "Destination" 710 having the value "0xFFFFFFFF" (for broadcast);
field "Source" 720 having the value of the master device address in the communication network;
field "Command" 730 having the value "0xF0" representative of a subwoofer absence
No data field included, or a data field comprising an identifier of the disconnected subwoofer.

According to the illustrated embodiment, in parallel to the tracking of the subwoofer presence, if a satellite speaker connects to the audio network, the method can further comprise detecting 420 the connection of a satellite speaker, accessing 430 the stored presence datum in order to determine the presence or the absence of a subwoofer, and sending 440 a message indicative of the presence or absence of a subwoofer to the newly connected satellite speaker.
In some embodiments where the default rendering mode of a newly connected speaker is known by the master device, the sending 440 can be optional, depending upon the presence or absence of a subwoofer. Indeed, in embodiments where the default audio rendering mode of a newly connected speaker is "high pass filter" mode, the sending of a message indicative of a presence of a subwoofer can be omitted, while the sending of a message indicative of the absence of a subwoofer can be mandatory. At the opposite, in embodiments where the default audio rendering mode of the newly connected speaker is "bass booster mode" the sending of a message indicative of a presence of a subwoofer can be mandatory, while the sending of a message indicative of the absence of a subwoofer can be omitted.
In a variant, the method can be performed in a master device of a sound system comprising a subwoofer that do not implement the method of the present disclosure. In such a case, the master device can obtain a connection information thanks to a user interface.
Figure 6 show a particular embodiment of the method 600 of the present disclosure, implemented in the illustrated embodiment in a satellite speaker or in a subwoofer. For instance, it can be one of the satellite speakers 140, 142, 144, 146 illustrated by figure 1 or the subwoofer 150 illustrated by figure 1. Of course, in other embodiments, the method can be embedded in other kinds of speaker.
In the particular embodiment described, the same firmware can be implemented in each audio renderer. The method can comprise, once the device is connected to the communication network, testing 610 (by reading of a variable located in a configuration file of a read only memory for instance) if the audio renderer is a satellite speaker or a subwoofer. If the audio renderer is a subwoofer, the method can comprise sending 670 a message representative of a presence of a subwoofer in the audio wireless network to the master device (as already explained in link with figure 4).
With the exemplary structure of message illustrated by Figure 7, the subwoofer device can for instance send a message with:

field "Destination" having the value the value "0xFFFFFFFF" (for broadcast) or the address of the master device in the communication network ;
field "Source" having the value of the subwoofer device address in the communication network;
field "Command" having the value "0xF1" representative of a subwoofer presence
No data field included.

In embodiments where the system can comprise at least two subwoofers, the data field can comprise an indication about the phasing of the audio signals rendered by the subwoofer or an identifier of the subwoofer.
A message where the destination field of the received message has the value dedicated to "broadcast", can be a way of asking the master device to retransmit the received message to all slaves present (even if the master device has no knowledge of the content of the field "command").
In the illustrated embodiment, the method can comprise setting 620 the audio rendering mode of the audio rendering device to a default value. This setting is optional. In some embodiments, the default value can be a static value configured by a manufacturer or retailer of the audio rendering device and stored in a Read Only Memory of the speaker. In such an embodiment, the value can be the same for each start-up of the speaker. In some embodiments, the default value can be a value previously set during a former powering on of the audio rendering device and memorized in a persistent memory of the speaker. In some embodiments, as detailed hereinafter, the default value can be read in a flash memory of the audio rendering device.
In the illustrated embodiment, the audio rendering mode can be for instance the high pass filter mode for a satellite speaker, or an "offset phase" mode in case of a subwoofer.
According to figure 6, the method can also comprise loading 630 an acoustic configuration (for instance a bass booster configuration), according to the default value assigned to the audio rendering mode of the audio rendering device. This loading 630 can be optional in some embodiments where the audio rendering device wait the message from the master device to configure its audio rendering mode.
The method can comprise receiving 640 a message from the master device. This message can for instance be indicative of a presence or an absence of a subwoofer in the network.
When the received message is indicative of a presence of a subwoofer (other than the audio rendering device where the method is implemented itself), there is no need of boosting bass if the audio rendering device that implements the method 600 is a satellite speaker. There is a need to offset the phase of the audio signal rendered if the audio rendering device that implements the method 600 is a subwoofer, in order to work in opposite phase, compared to the subwoofer newly present in the sound system. If an update of the audio rendering mode is needed 650, the method can comprise updating 660 the audio rendering mode of the audio rendering device (to a "high pass filter" mode or "offset phase" mode in the above example) and loading 670 an acoustic configuration adapted to this mode.
When the received message is indicative of an absence of a subwoofer (except eventually the audio rendering device where the method is implemented itself), there's a need of boosting bass 650 for a better audio rendering if the audio rendering device that implements the method 600 is a satellite speaker. If the audio rendering device that implements the method 600 is a subwoofer, no offset of the phase of the rendered audio signal is needed. If an update of the audio rendering mode is needed 650, the method can comprise updating 660 the audio rendering mode of the audio rendering device (to a "bass booster" mode or to a "no offset phase" mode in the above example) and loading 630 an acoustic configuration adapted to this mode.
In the particular embodiment described, the updating 620 can comprise storing 622 an information representative of the audio rendering mode in a FLASH memory of the audio rendering device. Depending upon embodiments, the storing 622 can be performed during, just before or just after the updating.
In such an embodiment, the method further can comprise accessing the stored information at the time of a booting of the audio rendering device (for instance after a pressure of a switch on/off button) and setting the audio rendering mode of the audio rendering device according to the stored value read.
It is to be noted that in some embodiments, different firmware can be embedded in a satellite speaker and in a subwoofer and/or only a subwoofer can be present in the system. In such a case, steps 610 and 670 can be optional for a satellite speaker and steps 610 to 660 can be optional for a subwoofer.
In a variant of the illustrated embodiment, at the booting of the audio renderer, when no message representative of the presence of a subwoofer has been received during a given duration (thanks a timer for instance), the audio renderer can assume that no subwoofer (except eventually the audio rendering device where the method is implemented itself) is present in the sound system, and can set its audio rendering mode accordingly. Similarly, in another variant, when no message representative of the absence of a subwoofer has been received during a given duration (thanks a timer for instance) at the booting of the audio renderer, the audio renderer can assume that a subwoofer (different eventually from the audio rendering device where the method is implemented) is present in the sound system and can set its audio rendering mode accordingly.
In a variant of the illustrated embodiments, the test 610 of being a subwoofer can be optional and the sending 670 can be performed for other kind of audio rendering devices.
For instance, in some embodiments when the audio rendering device is a satellite speaker, a medium speaker or a tweeter speaker, the method can comprise sending a message comprising its type of audio rendering device and/or its frequency range. With the exemplary structure of message illustrated by Figure 7, the speaker can for instance send a message with:

field "Destination" having the value the value "0xFFFFFFFF" (for broadcast) or the address of the master device in the communication network ;
field "Source" having the value of the speaker address in the communication network;
field "Command" having a value (like "0xF2") representative of a presence of a speaker being of its speaker type;
a data field comprising its frequency range.

Such a message can then be broadcasted by the master device (similarly to the particular embodiment illustrated by figure 4 but with a tracking of a presence and/or absence of the speaker).
In some embodiment, an audio rendering mode of an audio rendering device can be a "frequency range adaptation" mode (where the audio rendering device adapts the low and/or high frequency cut for an audio signal to be rendered) or an "unchanged frequency range" mode (where the audio rendering device keeps its own low and high frequency cut for an audio signal to be rendered) or a combination of one of those two modes with other modes. In such an embodiment, when a message is received (at 640) by an audio rendering device (for instance a subwoofer), the method can comprise comparing the frequency range received with the own frequency range of the audio rendering device. If the frequency ranges are different, then a change of the audio rendering mode is needed 650. The method can then comprise updating 660 the audio rendering mode of the audio rendering device with the value "frequency range adaptation" mode and, loading 630 an acoustic configuration of the audio rendering device accordingly. In such an embodiment, the loading 630 can comprise modifying the frequency range of the audio rendering device according to the type of audio rendering device and to the frequency range comprised in the received message.
For instance, if the audio rendering device implementing the method 600 is a subwoofer, and the received message concerns an audio rendering device of type "satellite speaker" or a "medium speaker", the method can comprise setting the high frequency cut of the subwoofer device to the low frequency cut received (or in other words, to the lowest value of the frequency range received).
if the audio rendering device implementing the method 600 is a tweeter speaker, and the received message concerns an audio rendering device of type "satellite speaker" or a "medium speaker", the method can comprise setting the low frequency cut of the tweeter speaker to the high frequency cut received (or in other words, to the highest value of the frequency range received).
Such an embodiment may permit to avoid an overlap of the frequencies of the audio signals rendered by different kind (or types) of audio rendering devices, or a frequency "hole" between audio signals rendered by the different kind (or types) of audio rendering devices.
In some embodiment, adapted to sound system comprising different types of audio rendering devices, the setting can be performed according to the highest of the low frequency cut and/or the lowest of the high frequency cut received and elated to a connected audio rendering device.
In another variant of the illustrated embodiments, the method 600 implemented in a first audio rendering device can comprise sending a message comprising the volume range of the first audio rendering device to the master device, which can track the presence and /or absence of the first audio rendering device and in turn broadcast the message to at least a second rendering device (similarly to the illustrated embodiment of figure 4). In some embodiment, the audio rendering mode of the second audio rendering device can be set to a "limited volume" mode (where the second audio rendering device adapts the volume range for an audio signal to be rendered according to the received message) or an "unchanged frequency range" mode (where the audio rendering device keep its own volume range for an audio signal to be rendered) or a combination of one of those two modes with other modes. In such an embodiment, the method 600 implemented in the second audio rendering device can comprise when a message is received (at 640), comparing the volume range received with the own volume range of the second audio rendering device. If the volume ranges are different, then a change of the audio rendering mode is needed 650. The method can then comprise updating 660 the audio rendering mode of the audio rendering device with the value "limited volume" mode and, loading 630 an acoustic configuration of the audio rendering device accordingly. In such an embodiment, the loading 630 can comprise modifying the volume range of the audio rendering device according to the volume range comprised in the received message.
For instance, if the second audio rendering device implementing the method 600 can work in a volume range from 0 to 100 dB, for instance, but the received message concerns an audio rendering device than can only work in a volume range from 0 to 30 dB, the method can comprise limiting the maximum volume rendered by the second audio rendering device to the highest value of the received volume range (that is to say the 30 dB value).
Such an embodiment can permit to get a better balancing of signal rendered by different kind (or types) of audio rendering devices.
In some embodiment, adapted to sound system comprising different types of audio rendering devices, the setting can be performed according to the lowest value of a higher limit of the volume range received and related to a connected audio rendering device.
The present disclosure has been described in relation with a particular protocol. Of course, as it can be understandable for a person skilled in the art, the present disclosure may also been applied in a communication system using other wireless network protocols.
As can be appreciated by one skilled in the art, aspects of the present principles can be embodied as a system, method, or computer readable medium. Accordingly, aspects of the present disclosure can take the form of an hardware embodiment, a software embodiment (including firmware, resident software, micro-code, and so forth), or an embodiment combining software and hardware aspects that can all generally be referred to herein as a "circuit", module" or "system". Furthermore, aspects of the present principles can take the form of a computer readable storage medium. Any combination of one or more computer readable storage medium may be utilized.
A computer readable storage medium can take the form of a computer readable program product embodied in one or more computer readable medium and having computer readable program code embodied thereon that is executable by a computer. A computer readable storage medium as used herein is considered a non-transitory storage medium given the inherent capability to store the information therein as well as the inherent capability to provide retrieval of the information therefrom. A computer readable storage medium can be, for example, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing.
It is to be appreciated that the following, while providing more specific examples of computer readable storage media to which the present principles can be applied, is merely an illustrative and not exhaustive listing as is readily appreciated by one of ordinary skill in the art: a portable computer diskette, a hard disk, a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.
Thus, for example, it can be appreciated by those skilled in the art that the block diagrams presented herein represent conceptual views of illustrative system components and/or circuitry of some embodiments of the present principles. Similarly, it can be appreciated that any flow charts, flow diagrams, state transition diagrams, pseudo code, and the like represent various processes which may be substantially represented in computer readable storage media and so executed by a computer or processor, whether or not such computer or processor is explicitly shown.

Claims

A method, adapted to be performed at a master device of a distributed sound system belonging to a communication network, said master device being adapted to output at least one audio channel to at least one audio rendering device of said sound system, said method comprising:
- obtaining at least one information representative of a connection, to said sound system, of an audio rendering device being of a first type of audio rendering devices;

- sending to at least one audio rendering device of said sound system an indication of presence of a connected audio rendering device of said first type in said sound system.
A method according to claim 1 wherein said sending is performed when no audio rendering device of said first type was connected to said sound system before said obtaining.
The method according to claim 1 or 2 comprising :
- detecting a disconnection of an audio rendering device of said first type to said sound system;

- sending to at least one audio rendering device of said sound system an indication of absence of a connected audio rendering device of said first type in said sound system.
The method according to any of claims 1 to 3 comprising, at a time of a connection of an audio rendering device to said sound system, sending an indication of presence or absence of an already connected audio rendering device of said first type in said sound system to said newly connected audio rendering device.
A master device of a distributed sound system belonging to a communication network, said master device being adapted to output at least one audio channel to at least one audio rendering device of said sound system and comprising at least one processor configured for:
- obtaining at least one information representative of a connection, to said sound system, of an audio rendering device being of a first type of audio rendering devices;

- sending to at least one audio rendering device of said sound system an indication of presence of a connected audio rendering device of said first type in said sound system.
A configuring method, adapted to be performed at an audio rendering device at a time of a connection of said audio rendering device to a distributed sound system belonging to a communication network, said method comprising sending to a master device of said sound system an information representative of a type of audio rendering devices to which said audio rendering device belongs to.
An audio rendering device adapted to be connected to a distributed sound system belonging to a communication network, said audio rendering device comprising at least one processor configured for sending to a master device of said sound system, at a time of a connection of said audio rendering device to said distributed sound system, an information representative of a type of audio rendering devices to which said audio rendering device belongs to.
A configuring method, adapted to be performed at an audio rendering device of a distributed sound system belonging to a communication network, for setting an audio rendering mode of said audio rendering device, wherein said setting is performed according to at least one information received from a master device of said distributed sound system.
The configuring method of claim 9 wherein said information is representative of a presence and/or an absence of a connected audio rendering device of a first type in said distributed sound system.
The configuring method of claim 10 wherein said method is adapted to be performed at an audio rendering device of a second type.
An audio rendering device adapted to be connected to a distributed sound system belonging to a communication network, said audio rendering device comprising at least one processor configured for setting an audio rendering mode of said audio rendering device, wherein said setting is performed according to at least one information received from a master device of said sound system.
A distributed sound system belonging to a communication network and comprising a least one master device, said master device being adapted to output at least one audio channel to at least one audio rendering device of said sound system, wherein:
- said master device comprises at least one processor configured for:
• obtaining at least one information representative of a connection, to said sound system, of a first audio rendering device, said first audio rendering device being of a first type of audio rendering devices;

• sending to at least one second audio rendering device of said sound system an indication of presence of a connected audio rendering device of said first type in said sound system;

- said second audio rendering device comprises at least one processor configured for setting an audio rendering mode of said second audio rendering device, said setting being performed according to said indication sent by said master device.
A non-transitory computer readable program product comprising program code instructions for performing the method according to at least one of claims 1 to 4, 6 to 7, 9 to 10, when said non-transitory software program is executed by a computer.
Computer readable storage medium carrying a software program comprising program code instructions for performing the method according to at least one of claims 1 to 4, 6 to 7, 9 to 10, when said non-transitory software program is executed by a computer.
Electronic signal exchanged between a master device and at least one audio rendering device of a distributed sound system belonging to a communication network, said electronic signal comprising an information representative of a presence of a connected audio rendering device of a first type to said sound system.