Patent Publication Number: US-2023164273-A1

Title: Systems and methods to automatically join conference

Description:
BACKGROUND 
     This disclosure is directed to enabling a device of a user to automatically join an on-going conference, where the device is not currently joined to the conference. In particular, such a device is enabled to join the conference based on whether an audio signature associated with a plurality of voices of users already in the conference matches an audio signature generated based on an audio signal captured by a device associated with the user. 
     SUMMARY 
     Advancements in communication technology have improved the ability of users to communicate (e.g., such as via video conferencing) with colleagues, family and friends located in a different physical location than the user. For example, conferencing systems (e.g., Microsoft Teams™, Zoom™, etc.) are often used to enable colleagues in separate, geographically distributed physical locations to have a face-to-face conversation via a video conference. In some circumstances, multiple devices in a single location may be joined to a conference (e.g., in a physical conference room at an office), and other users in different geographical locations may also be participating in the conference over a network. However, having multiple devices joined to a conference in the same physical location may cause several issues. For example, audio feedback (e.g., a high-pitched screech or squeal) may be created if a signal received by a microphone of one of the devices is fed to a speaker, and such signal is output by the speaker and again received by the microphone. Such audio feedback can be distracting and irritating to users participating in the conference. In addition, although a user may be present at the conference, it may be the case that the user is in a conference room with multiple users participating in the conference via a single device joined to the conference. In this situation, other conference participants may be unaware the user is participating in the conference (e.g., if an icon associated with the user is not presented on a display associated with the conference call). Moreover, there may no record of the user having participated in the conference. 
     In one approach, a user may manually select an option to join a conference and select a mute option presented on a display of his or her device, in order to avoid audio feedback. However, this may be burdensome for the user. In particular, the user may not know a conference ID that may be required to join the conference. Additionally, there may be a delay between joining the conference and the audio being muted. In this circumstance, other users may be subjected to undesirable audio feedback while the user is attempting to mute his or her device. Alternatively, the user may decide not to bring his or her device to the conference room, and thus other users joined to the conference (e.g., over the network and not present in the conference room) may not recognize that the user is participating in the conference. 
     To overcome these problems, systems and methods are provided herein for automatically joining a device associated with a first user to a conference of a plurality of users when the user is proximate to another device already joined to the conference. A conferencing server may generate (and store) a first audio signature based on voices of the plurality of users already in the conference. Later, a new device that is not joined to the conference attempts to join the conference and may capture a sample of ambient sounds using a microphone. In some embodiments, the new device locally generates a second audio signature based on the ambient sample and transmits the second audio signature to the server. In some embodiments, the new device sends the ambient sounds to the conferencing server, allowing the server to generate the second signature. In response to determining that first audio signature matches the second audio signature, the device associated with the first user is joined to the conference. 
     In some aspects of the disclosure, the audio signal captured by the microphone of the device associated with the first user comprises at least one of the voices of the plurality of users in the conference. For example, a conferencing application may determine whether the device associated with the first user is in a same physical location as a device associated with at least one user of the plurality of users in the conference, and the audio signal captured by the microphone of the device associated with the first user may be captured in response to determining that the device associated with the first user is in a same physical location as the device associated with the at least one user. In some embodiments, the device may attempt to join in response to a request (e.g., via a user interface) to join a conference. For example, the user may say “Join current conference,” or click or touch a button labeled “Join current conference.” 
     The joining of the device associated with the first user to the conference may comprise generating for presentation an icon indicating to each user joined to the conference that the first user is joined to the conference. In this way, other users participating in the conference (e.g., over the network and not present in a conference room with the first user) may be made aware that the user is participating in the conference. In addition, after the device associated with the first user is joined to the conference, the conferencing application may cause the microphone and a speaker of the device associated with the first user to be automatically muted without receiving a user command to mute the microphone and the speaker. Accordingly, audio feedback that may be distracting and irritating to users in the conference can be avoided. 
     In some aspects of the disclosure, the conferencing server may assign a conference identifier to the conference, and associate a first audio signature with the conference identifier, and joining the device associated with the first user to the conference may comprise transmitting the conference identifier to the device associated with the first user. 
     In some embodiments, the first audio signature and the second audio signature are generated by sampling the voices of the plurality of users in the conference and the audio signal captured by the microphone, respectively, at regular intervals. The first audio signature and the second audio signature may also be generated by transcribing the voices of the plurality of users in the conference and the audio signal captured by the microphone, respectively, into text. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other objects and advantages of the present disclosure will be apparent upon consideration of the following detailed description, taken in conjunction with the accompanying drawings, in which like reference characters refer to like parts throughout, and in which: 
         FIG.  1    shows an example of joining a device associated with a user to a conference, in accordance with some embodiments of this disclosure; 
         FIG.  2    shows an example of generating an audio signature, in accordance with some embodiments of this disclosure; 
         FIG.  3    shows an example of a user entering a conference room in which users are participating in a conference, in accordance with some embodiments of this disclosure; 
         FIG.  4    is a diagram of illustrative conferencing devices, in accordance with some embodiments of this disclosure; 
         FIG.  5    is a diagram of an illustrative conferencing system, in accordance with some embodiments of this disclosure; 
         FIG.  6    is a flowchart of a detailed illustrative process for joining a device associated with a user to a conference, in accordance with some embodiments of this disclosure; and 
         FIG.  7    is a flowchart of a detailed illustrative process for joining a device associated with a user to a conference, in accordance with some embodiments of this disclosure. 
     
    
    
     DETAILED DESCRIPTION 
       FIG.  1    shows an example  100  of joining a device associated with user  106  to conference  105 . In some embodiments, a conferencing application joins users to a video and/or audio conference to enable communication with other users over a network. For example, the conferencing application joins a device associated with user  102 , and a device associated with user  104 , to conference  105 ), and users  102  and  104  may be located in different geographical locations (e.g., user  102  may be present in conference room  101  located in New York, while user  104  may be present in conference room  103  located in California). Once users  102  and  104  join the conference, the conferencing application may enable the users to communicate with one another (e.g., via audio, video and/or text message) using one or more digital devices. The voices  107  of users  102  and  104  may be detected (e.g., by respective microphones of conferencing devices located in conference rooms  101  and  103 ), and the conferencing application may generate (e.g., locally or at a conferencing server) an audio signature based on such detected voices. The generated audio signatures may be stored at the conferencing server (e.g., server  508  in  FIG.  5   ) in association with a conference ID. The signature may be generated using a suitable voice processing technique (e.g., as described in  FIG.  2   ). 
     The conferencing application may then determine that user  106  (whose device is not yet joined to the conference), associated with device  110  (e.g., a mobile device held by the user  106 , and running the conferencing application), has physically entered conference room  103  (or otherwise became proximate to conference Room  103 ), in which user  104  is already participating in conference  105 . Such determination may be performed in any suitable manner (e.g., as discussed in more detail in  FIG.  3   ). Once the conferencing application determines that user  106  has entered conference room  103 , microphone  113  of device  110  associated with user  106  may be triggered to begin detecting ambient audio. For example, the microphone  113  may detect the voices of user  102  (e.g., over the network) and user  104  (e.g., in person in conference room  103 ) participating in the conference, and sample the detected voices of user  102  and user  104 . The conferencing application may generate (e.g., locally or at a conferencing server) an audio signature  116  based on the detected ambient audio signal  114 . The conferencing server may receive the generated audio signature  116 , and the conferencing application may compare audio signature  116  to the generated audio signature  108 . If the conferencing application determines that audio signature  116  matches audio signature  108 , device  110  of user  106  may be joined to conference  105 , to enable the user  106  to communicate over the network with user  102 , located in a different physical location from user  106 . In some embodiments, the microphone of device  110  may be automatically muted (e.g., without receiving further user input), after device  110  of user  106  is joined to conference  105 , thereby minimizing or avoiding audio feedback. If the conferencing application determines that audio signature  116  does not match audio signature  108 , the conferencing application may determine that user  106  should not be joined to conference  105 . This may be advantageous for various reasons (e.g., to avoid joining a device of a user to the conference in a circumstance where the user may have happened to walk by a conference room but did not intend to (or was not invited to) join the conference, thereby conserving network and/or device resources). 
     In some embodiments, the microphone  113  of the device  110  may be triggered in response to the conferencing application receiving a request to join from the user (e.g., via a selectable option on a user interface of the device, via voice command, etc.). For example, the conferencing application may detect that a new device (e.g., device  110 ) is attempting to join the conference  105 , and the conferencing application may trigger a microphone of a device (e.g., a device associated with user  102 ) of a user known to be joined to the conference, as well as the microphone of the device attempting to join the conference. The conferencing application may generate audio signatures based on the captured audio of the microphone  113  of the device  110  and the captured audio of the device associated with user  102 , and join the device  110  to the conference  105  upon determining the audio signatures match. 
       FIG.  2    shows an exemplary process of generating an audio signature. As referred to herein, the term “audio signature” or “audio fingerprint” may refer to any kind of a digital or analog representation of a sound. The audio signature may be a digital measure of certain acoustic properties that is deterministically generated from an audio signal and may be used to identify an audio sample and/or quickly locate similar items in an audio database. For example, an audio signature may be a file, data, or data structure that stores time-domain sampling of an audio input. In another example, an audio signature may be a file, data, or data structure that stores a frequency-domain representation (e.g., a spectrogram) of an audio input. Exemplary generation of audio signatures is described in greater detail in Blake et al., U.S. Patent Application Publication No. 2019/0391788 A1, filed Jun. 26, 2018; Sanchez et al., U.S. Patent Application Publication No. 2020/0186893 A1, filed Feb. 12, 2020; Khan et al., U.S. Pat. No. 7,853,344, issued Dec. 14, 2010; and Bogdanov, U.S. Pat. No. 7,451,078, issued Nov. 11, 2008, which are hereby incorporated by reference herein in their entireties. 
     As shown in  FIG.  2   , microphone  204  may receive audio input  202  (e.g., a voice of a user in the conference, background noise, music, recorded audio, and/or other suitable audio signals), and convert audio input  202  into an electrical signal. The detected audio input  202  may include frequencies in a range of 20 Hz to 20 kHz (e.g., the sound wave frequency that may be heard by the human ear). In some embodiments, audio input  202  may be sampled at regular intervals (e.g., periods of 1-2 seconds with samples taken every few milliseconds during the period). For example, audio input  202  may be various segments of the audio of the conference. The electrical signal output by the microphone  204  may be an analog output, and may be digitized at digital signal processor  206  to facilitate further processing. In some embodiments, the microphone  204  may be a MEMS microphone with a digital output. 
     The digital signal processor  206  (e.g., included in a general-purpose microprocessor or a specialized digital signal processor) may perform various operations on the received digital signal. In some embodiments, the digital signal processor  206  may perform a fast Fourier transform operation on time-domain samples of the audio to produce a frequency-domain representation of the audio. In some embodiments, the digital signal processor  206  may employ audio compression techniques, to reduce network resources and/or computing power to process the signal. In some embodiments, noise reduction techniques may be employed (e.g., in a pre-processing stage) to filter out unwanted signals. 
     The generated audio signature  208  may comprise a time-domain and/or frequency-domain representation (e.g., a spectrogram) of the signal. In some embodiments, the device (e.g., device  110  of  FIG.  1   ) associated with the user (e.g., user  106  of  FIG.  1   ) may transmit an encoded time-domain representation of the signal to a server and receive and decode a frequency-domain representation of the signal. In some embodiments, digital signal processing including frequency analysis, peak volume detecting, audio hashing, waveform matching, and/or any other digital signal processing method known to those skilled in the art may be used to generate an audio signature. As another example, the audio signature may comprise an audio signature or hash calculation deterministically generated from a predefined portion of the audio signal. 
     In some embodiments, the conferencing application may generate a features vector based on the output of the digital signal processor  206 , and audio signature  208  may correspond to such features vector. For example, the features vector may comprise a sequence of values representing various audio or acoustic features or characteristics (e.g., amplitude, modulation, tone, frequency, volume, speed, etc.) of the signal. Audio processing circuitry may analyze audio characteristics of the signal to identify audio signatures using any suitable audio analysis technique (e.g., frequency analysis to determine a base frequency and unique harmonic pattern of a particular voice, phoneme analysis to determine an accent of a particular voice, etc.). For example, the wave amplitude of the audio signal may be used to determine the volume of the voice of user  202  and/or analyze frequency data to determine the pitch and tone of the voice search query. The audio processing circuitry may also identify non-vocal audio such as music, sound effects, and the like using similar frequency analysis techniques or any other suitable method of audio analysis. The identified audio characteristics may be stored in association with a timestamp of when the audio signal was received. Audio signal processing is discussed in more detail in U.S. patent application Ser. No. 16/553,410, filed Aug. 28, 2019, which is hereby incorporated by reference herein in its entirety. 
     In some embodiments, the audio signal may be converted to transcribed text, and such text may be used to generate audio signature  208 . For example, the conferencing application may transcribe the audio response into a string of text (e.g., by any suitable automatic speech recognition technique), or transcription of the audio signal may be achieved by external transcription services (e.g., Amazon Transcribe by Amazon, Inc. of Seattle, Wash. and Google Speech-to-Text by Google, Inc. of Mountain View, Calif.). The transcription of audio is discussed in more detail in U.S. patent application Ser. No. 16/397,004, filed Apr. 29, 2019, which is hereby incorporated by reference herein in its entirety. 
       FIG.  3    shows an example of joining a user  310  to an ongoing conference  301 . Users  306 ,  308  are depicted as physically present in conference room  300 , and each of users  306  and  308  are already joined to the conference and communicating via conferencing device  302  with other conference participants located in different physical locations. The conferencing device  302  may include a camera and a microphone to facilitate communication between the users present in conference room  300  and users located in other physical locations (e.g., users  314 ,  316 ,  318 ). In some embodiments, the conferencing application may display a video feed of such users  314 ,  316 ,  318  at projector screen  304 , and/or icons  312  for each user, to indicate which users are participating in the conference. The conferencing application may also display a video feed of the conference room  300  to users  314 ,  316  and  318  in their respective locations via their respective devices, and the video feed of the users  314 ,  316  and  318  (and the conference room  300 ) may also be presented on projector screen  304 . 
     When the user  310  enters conference room  300 , the conferencing application (e.g., running at least in part on device  311  associated with the user  310 ) may activate the microphone of device  311  to capture sound in the conference room  300 . For example, in order to optimally utilize network and/or device resources, it may be desirable for the conferencing application to be activated (e.g., begin sampling ambient audio) only upon determining the user has entered a physical conference room where devices associated with the conference are located. The conferencing application may determine that the user  310  has entered the conference room  300  using any suitable method. 
     In some embodiments, the conferencing application may determine that the user has entered the conference room  300  based on GPS data retrieved from device  311 , or based on an IP address associated with device  311 , to determine the user&#39;s geographic location. For example, the conferencing application may compare GPS coordinates associated with device  311  to GPS coordinates or IP address information associated with devices currently joined to the conference (e.g., stored at a conferencing server). If the comparison indicates that the user  310  is in the same location as device  302  (e.g., within a predetermined threshold distance, such as 10-20 feet), the conferencing application may determine that the user  310  has entered conference room  300 . As another example, the conferencing application may determine whether device  311  is within a threshold distance of device  302  based on a wireless signal strength between the devices (e.g., polling nearby devices). For example, the conferencing application may determine a relative received signal strength indicator (RSSI) of a wireless signal between device  311  and the conferencing device  302 , and based on the RSSI, an estimated distance between device  311  and device  302  (e.g., using a lookup table that returns distance as a function of RSSI). In another example, the conferencing application may measure received radio frequency (RF) power over a shared wireless signal to estimate a location of the user. As another example, the conferencing application may employ any suitable computer vision or facial recognition techniques (e.g., on an image or video feed of a camera of a device already joined to an ongoing conference or of a device not yet joined to the conference) to recognize a user to be added to an ongoing conference. 
     In some embodiments, the conferencing application may determine that the user has entered the conference room  300  by polling other devices joined to the conference, to determine whether the user  310  and device  311  are in the vicinity of a threshold number of devices (e.g., five devices) joined to the conference. As another example, the conferencing application may monitor a smart lock or an RFID chip in the user&#39;s mobile phone to determine whether the user has entered a conference room or physical location where conference participants are located. In some embodiments, the conferencing system may monitor the location of device  311  during the conference, and upon determining that device  311  has left the conference room  300 , may automatically remove the user  310  from the conference (and remove any indicators that the user is still participating in the conference). In some embodiments, a selectable option on the device  311  may be selected by the user  310  to attempt to join the current conference (e.g., conference  301 ). The conferencing application may then confirm that the device  311  is within a predetermined proximity to other devices participating in the conference (e.g., prior to triggering microphones of the devices to capture audio, and generating audio signatures based on the captured audio). 
     When the conferencing application determines that device  311  associated with user  310  has entered the conference room  300 , the microphone of device  311  may be activated to sample ambient audio in the conference room  300 . It should be noted that the determination may be based on proximity to other devices joined to the conference, and may not be room related or based on entering a particular room. In some embodiments, the microphone may be configured to capture audio of only the users within the conference room  300  where device  311  is located, or alternatively capture audio of both the conference room  300  and audio over the network (e.g., received from one or more devices associated with users  314 ,  316 ,  318 ). As discussed in connection with  FIG.  1   , and as discussed in more detail below, the conferencing application (e.g., at device  311  or at a conferencing server) may generate an audio signature based on the ambient audio detected by device  311 , and may join the user to the conference upon determining that such generated audio signature matches audio signatures stored at the conferencing server (e.g., and which are associated with a conference ID of the conference). In some embodiments, when the user  310  is joined to the conference, the conferencing application may cause the microphone, camera and/or speaker of device  311  to be automatically muted and/or disabled, to avoid subjecting other conference participant&#39;s to audio feedback, and may cause the display of an icon on projector  304  indicating to all conference participants that the user  310  is now participating in the conference. 
       FIG.  4    shows generalized embodiments of illustrative conferencing devices  400  and  401 . Any of the devices discussed in connection with  FIGS.  1 - 3    may be implemented as conferencing devices  400  or  401 . The conferencing application may be executed on any combination of conferencing device  400  and/or device  401  (e.g., locally) and/or conferencing server  508  (e.g., remotely) of  FIG.  5   , and the steps illustrated in  FIGS.  1 - 3    may be performed by the conferencing application locally or remotely. As depicted, conferencing device  400  may be a smartphone or tablet, whereas conferencing device  401  may be a conferencing system that includes equipment device  416  (e.g., a PC, set-top box, CPU, video-game console, etc.). Conferencing devices  400  and  401  may receive content and data via input/output (hereinafter “I/O”) path  402  (e.g., I/O circuitry). I/O path  402  may provide content (e.g., Internet content, content available over a local area network (LAN) or wide area network (WAN), and/or other content) and data to control circuitry  404 , which includes processing circuitry  406  and storage  408 . Control circuitry  404  may be used to send and receive commands, requests, and other suitable data using I/O path  402 . I/O path  402  may connect control circuitry  404  (and specifically processing circuitry  406 ) to one or more communications paths (described below). I/O path  402  may additionally provide circuitry to control user interface  410 . I/O functions may be provided by one or more of these communications paths but are shown as a single path in  FIG.  4    to avoid overcomplicating the drawing. 
     Control circuitry  404  may be based on any suitable processing circuitry such as processing circuitry  406 . As referred to herein, processing circuitry should be understood to mean circuitry based on one or more microprocessors, microcontrollers, digital signal processors, programmable logic devices, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), etc., and may include a multi-core processor (e.g., dual-core, quad-core, hexa-core, or any suitable number of cores) or supercomputer. In some embodiments, processing circuitry may be distributed across multiple separate processors or processing units, for example, multiple of the same type of processing units (e.g., two Intel Core i7 processors) or multiple different processors (e.g., an Intel Core i5 processor and an Intel Core i7 processor). In some embodiments, control circuitry  404  executes instructions for a conferencing system stored in memory (e.g., storage  408 ). Specifically, control circuitry  404  may be instructed by the conferencing system to perform the functions discussed above and below. 
     In client-server-based embodiments, control circuitry  404  may include communications circuitry suitable for communicating with a conferencing system server (e.g., server  508  of  FIG.  5   ) or other networks or servers. The instructions for carrying out the above-mentioned functionality may be stored on a server. Communications circuitry may include a cable modem, an integrated service digital network (ISDN) modem, a digital subscriber line (DSL) modem, a telephone modem, Ethernet card, or a wireless modem for communications with other equipment, or any other suitable communications circuitry. Such communications may involve the Internet or any other suitable communications networks or paths. In addition, communications circuitry may include circuitry that enables peer-to-peer communication of conferencing devices, or communication of conferencing devices in locations remote from each other. 
     As referred to herein, the phrase “conferencing device” and “user device” should be understood to mean any device for accessing the content described above, such as a television, a Smart TV, a set-top box, an integrated receiver decoder (IRD) for handling satellite television, a digital storage device, a digital media receiver (DMR), a digital media adapter (DMA), a streaming media device, a personal computer (PC), a laptop computer, a tablet, a WebTV box, a smart phone, or any other television equipment, computing equipment, or wireless device, and/or combination of the same. 
     Memory may be an electronic storage device provided as storage  408  that is part of control circuitry  404 . As referred to herein, the phrase “electronic storage device” or “storage device” should be understood to mean any device for storing electronic data, computer software, or firmware, such as random-access memory, read-only memory, hard drives, optical drives, digital video disc (DVD) recorders, compact disc (CD) recorders, BLU-RAY disc (BD) recorders, BLU-RAY 3D disc recorders, digital video recorders (DVRs, sometimes called personal video recorders, or PVRs), solid state devices, quantum storage devices, gaming consoles, gaming media, or any other suitable fixed or removable storage devices, and/or any combination of the same. Nonvolatile memory may also be used (e.g., to launch a boot-up routine and other instructions). Cloud-based storage, described in relation to  FIG.  5   , may be used to supplement storage  408  or instead of storage  408 . 
     Control circuitry  404  may include audio circuitry, video circuitry, and tuning circuitry, such as one or more analog tuners, one or more MP4 decoders or other digital decoding circuitry, or any other suitable tuning or audio circuits or combinations of such circuits. Encoding circuitry (e.g., for converting over-the-air, analog, or digital signals to audio signals for storage) may also be provided. Control circuitry  404  may also include scaler circuitry for upconverting and downconverting content into the preferred output format of the conferencing device  400 . Circuitry  404  may also include digital-to-analog converter circuitry and analog-to-digital converter circuitry for converting between digital and analog signals. The tuning and encoding circuitry may be used by the conferencing device to receive and to display, to play, or to record content. The tuning and encoding circuitry may also be used to receive guidance data. The circuitry described herein, including, for example, the tuning, audio-generating, encoding, decoding, encrypting, decrypting, scaler, and analog/digital circuitry, may be implemented using software running on one or more general purpose or specialized processors. Multiple tuners may be provided to handle simultaneous tuning functions. If storage  408  is provided as a separate device from user device  400 , the tuning and encoding circuitry (including multiple tuners) may be associated with storage  408 . 
     A user may send instructions to control circuitry  404  using user input interface  410 . User input interface  410  may be any suitable user interface, such as a remote control, mouse, trackball, keypad, keyboard, touchscreen, touchpad, stylus input, joystick, voice recognition interface, or other user input interfaces. Display  412  may be a touchscreen or touch-sensitive display. In such circumstances, user input interface  410  may be integrated with or combined with display  412 . Display  412  may be provided as a stand-alone device or integrated with other elements of each one of conferencing device  400  and device  401 . Speakers  414  may be provided as integrated with other elements of each of conferencing device  400  and device  401 . In the case of conferencing device  401 , speakers  414  may be stand-alone units (e.g., smart speakers). The audio component of videos and other content displayed on display  412  may be played through speakers  414 . In some embodiments, the audio may be distributed to a receiver (not shown), which processes and outputs the audio via speakers  414 . 
     The conferencing application may be implemented using any suitable architecture. For example, it may be a stand-alone application wholly implemented on conferencing device  400  and/or  401 . In such an approach, instructions of the application are stored locally (e.g., in storage  408 ), and data for use by the application is downloaded on a periodic basis (e.g., from an out-of-band feed, from an Internet resource, or using another suitable approach). Control circuitry  404  may retrieve instructions of the application from storage  408  and process the instructions to generate any of the displays discussed herein. Based on the processed instructions, control circuitry  404  may determine what action to perform when input is received from input interface  410 . For example, movement of a cursor on a display up/down may be indicated by the processed instructions when input interface  410  indicates that an up/down button was selected. 
     In some embodiments, the conferencing application is a client/server-based application. Data for use by a thick or thin client implemented on device  400  or device  401  may be retrieved on-demand by issuing requests to a server (e.g., conferencing server  508  of  FIG.  5   ) remote to the device  400  or device  301 . In one example of a client/server-based conferencing application, control circuitry  404  runs a web browser that interprets web pages provided by a remote server (e.g., conferencing server  508 ). For example, the remote server may store the instructions for the application in a storage device. The remote server may process the stored instructions using circuitry (e.g., control circuitry  404 ) and generate the displays discussed above and below. The user device may receive the displays generated by the remote server and may display the content of the displays locally on device  400  or device  401 . This way, the processing of the instructions is performed remotely by the server while the resulting displays are provided locally on device  400  or device  401 . Device  400  or device  401 may receive inputs from the user via input interface  410  and transmit those inputs to the remote server for processing and generating the corresponding displays. For example, on device  400  or device  401  may transmit a communication to the remote server indicating that an up/down button was selected via input interface  410 . The remote server may process instructions in accordance with that input and generate a display of the application corresponding to the input (e.g., a display that moves a cursor up/down). The generated display is then transmitted to device  400  or device  401  for presentation to the user. 
     In some embodiments, the conferencing application is downloaded and interpreted or otherwise run by an interpreter or virtual machine (run by control circuitry  404 ). In some embodiments, the application may be encoded in the ETV Binary Interchange Format (EBIF), received by control circuitry  404  as part of a suitable feed, and interpreted by a user agent running on control circuitry  404 . For example, the application may be an EBIF application. In some embodiments, the guidance application may be defined by a series of JAVA-based files that are received and run by a local virtual machine or other suitable middleware executed by control circuitry  404 . In some of such embodiments (e.g., those employing MPEG-2 or other digital media encoding schemes), the application may be, for example, encoded and transmitted in an MPEG-2 object carousel with the MPEG audio and video packets of a program. 
     Conferencing device  400  and conferencing device  401  of  FIG.  4    can be implemented in system  500  of  FIG.  5    as any combination of conferencing device  502 , conferencing device  505 , or conferencing device  506 . Conferencing devices, on which a conferencing system may be implemented, may function as stand-alone devices or may be part of a network of devices. Conferencing server  508  may have a similar configuration to conferencing device  401 , although conferencing server  508  may not include certain elements (e.g., a display, a user interface, speakers, etc.). Various network configurations of devices may be implemented and are discussed in more detail below. 
     In system  500 , there may be multiple conferencing devices, but only three are shown in  FIG.  5    to avoid overcomplicating the drawing. In addition, each user may utilize more than one type of conferencing device and also more than one of each type of conferencing device. 
     Conferencing devices  502 ,  505 ,  506  may be coupled to communication network  504 . Communication network  504  may be one or more networks including the Internet, a mobile phone network, mobile voice or data network (e.g., a 4G or LTE network), cable network, public switched telephone network, or other types of communications network or combinations of communications networks. Conferencing server  508 , and conferencing devices  502 ,  505 ,  506  may be coupled to communications path  504  via one or more communications paths, such as a satellite path, a fiber-optic path, a cable path, a path that supports Internet communications (e.g., IPTV), free-space connections (e.g., for broadcast or other wireless signals), or any other suitable wired or wireless communications path or combination of such paths. 
     Although communications paths are not drawn between conferencing devices  502 ,  505 ,  506 , and conferencing server  508 , these devices may communicate directly with each other via communications paths, such as short-range point-to-point communications paths, such as USB cables, IEEE 1394 cables, wireless paths (e.g., Bluetooth, infrared, IEEE 802-11x, etc.), or other short-range communication via wired or wireless paths. BLUETOOTH is a certification mark owned by Bluetooth SIG, INC. The conferencing devices may also communicate with each other through an indirect path via communication network  504 . 
     Conferencing applications may be, for example, stand-alone applications implemented on conferencing devices. For example, the conferencing application may be implemented as software or a set of executable instructions, which may be stored in storage  408  and executed by control circuitry  404  of a conferencing device  502 ,  505 ,  506 . In some embodiments, conferencing systems may be client-server applications where only a client application resides on the conferencing device, and a server application resides on conferencing server  508 . For example, conferencing systems may be implemented partially as a client application on control circuitry  404  of conferencing devices  502 ,  505 ,  506  and partially on conferencing server  508  as a server application running on control circuitry of conferencing server  508 . When executed by control circuitry of conferencing server  508 , the conferencing application may instruct the control circuitry to capture audio, generate audio signatures (e.g., based on captured audio), join a device to the conference, and generate the conferencing system output (e.g., a video feed of the conference, audio feed of the conference, text chat or other functionalities for the conference, etc.) and transmit a conference ID (e.g., to a device newly joined to a conference) and the generated output to conferencing devices  502 ,  505 ,  506 . The client application may instruct control circuitry of the receiving conferencing devices  502 ,  505 ,  506  to generate the conferencing system output. 
     Conferencing devices  502 ,  505 ,  506  may operate in a cloud computing environment to access cloud services. In a cloud computing environment, various types of computing services for content sharing, storage or distribution (e.g., video sharing sites or social networking sites) are provided by a collection of network-accessible computing and storage resources, referred to as “the cloud.” Cloud resources may be accessed by conferencing device  502 ,  505 ,  506  using, for example, a web browser, a conferencing system, a desktop application, a mobile application, and/or any combination of access applications of the same. Conferencing devices  502 ,  505 ,  506  may be a cloud client that relies on cloud computing for application delivery, or the conferencing device may have some functionality without access to cloud resources. For example, some applications running on conferencing device  502 ,  505 ,  506  may be cloud applications, i.e., applications delivered as a service over the Internet, while other applications may be stored and run on the conferencing device. In some embodiments, a user device may receive content from multiple cloud resources simultaneously. For example, a user device can stream audio from one cloud resource while downloading content from a second cloud resource. Or a user device can download content from multiple cloud resources for more efficient downloading. In some embodiments, conferencing devices can use cloud resources for processing operations such as the processing operations performed by processing circuitry described in relation to  FIG.  4   . 
       FIG.  6    shows a processing flow  600  for joining device  601  to a conference, in accordance with some embodiments of this disclosure. It should be noted that process  600  or any step thereof could be performed on, or provided by, any of the devices shown in  FIGS.  4 - 5   . For example, process  600  may be executed by devices  502 ,  505 ,  506  (e.g., via control circuitry  404 ) and/or control circuitry of conferencing server  508 , as instructed by a conferencing application that may be implemented on conferencing device  502 , and/or conferencing device  505  and/or conferencing device  506  and/or conferencing server  508 , such as to distribute control of database management application operations for a target device among multiple devices. In addition, one or more steps of process  600  may be incorporated into or combined with one or more steps of any other process or embodiment (e.g., process  700  of  FIG.  7   ). 
     At  602 , control circuitry of a conferencing server  603  (e.g., server  508  of  FIG.  5   ) may establish a conference (e.g., conference  105  of  FIG.  1   , conference  301  of  FIG.  3   ) via a communication network (e.g., network  504  of  FIG.  5   ). For example, conferencing server  603  may communicate with users via one or more devices  605  (e.g., devices  502 ,  505 ,  506  of  FIG.  5   ) to set up the conference. In some embodiments, at least one of such users may be physically present in a conference room (e.g., conference room  300  of  FIG.  3   ). The conference may include multiple participants from several different physical locations, and at any of such locations there may be a single user or multiple users present (e.g., communicating via a single device, such as device  302  of  FIG.  3   , in a conference room, or communicating via multiple devices). The conference may be associated with a unique conference ID stored at conferencing server  603 , and such conference ID may be communicated to each of devices  605  to enable the devices  605  to join the conference. 
     At  604 , a microphone of each of one or more devices (e.g., devices  502 ,  505 ,  506  of  FIG.  5   ) joined to the conference may capture audio signals of voices of users in the conference. The captured audio signals (e.g., audio input  202  of  FIG.  2   ) may be sampled at regular intervals (e.g., periods of 1-2 seconds with samples taken every few milliseconds during the period). In some embodiments, the microphone may pick up ambient sounds (e.g., voices of users in the same physical location as the microphone, voices of users joined to the conference in a different physical location, background noise, music, etc.) and certain frequencies or noise may be filtered from the signal (e.g., using digital signal processor  206  of  FIG.  2    and/or control circuitry of the devices  605  or conferencing server  603 ). For example, noise or other background sounds may be removed from the signal, and/or only voices of users in the same room as the microphone may be included in the signal (e.g., only voices above a threshold amplitude may be included in the signal, since volume of the voice may be louder in the same physical location than over a network). An analog filter (e.g., to block signals not within a frequency of the human voice) or digital filter (e.g., by applying an algorithm to a sequence of digital samples) may be employed. 
     At  606 , the captured audio signals may be transmitted to conferencing server  603 . In some embodiments, the captured audio signal may be transmitted from each of the devices  605  joined to the conference at the same time, or at various predetermined times. The captured audio signals may be transmitted to conferencing server  603  each time the audio is sampled by the respective devices. 
     At  608 , control circuitry of conferencing server  603  (and/or digital signal processor  206  of  FIG.  2   ) may generate audio signatures based on the audio signals (e.g., received via I/O path  402  of  FIG.  4   ), such as in accordance with the techniques discussed in connection with  FIG.  2   . For example, audio modulations of the received signals may be compressed into audio signatures. Various digital signal processing algorithms may be used (e.g., fast Fourier transform) in generating the audio signatures. In some embodiments, the audio can be converted to transcribed text (e.g., using ASR and/or speech-to-text circuitry) and such transcribed text may be used as an audio signature. The audio signature may be generated for each audio signal received by conferencing server  603  from the devices  605  joined to the conference, and audio signals may be transmitted to the server (e.g., at predetermined times, for the purposes of generating audio signatures) until the conclusion of the conference. 
     At  610 , control circuitry of conferencing server  603  (e.g., server  508  of  FIG.  5   ) may store (e.g., in storage  408  of  FIG.  4   ) the generated audio signatures in connection with the conference ID associated with the conference. In addition to the conference ID, the generated signatures may be associated and/or tabulated with device IDs respectively associated with devices  605  joined to the conference, and a timestamp associated with each audio signature. In some embodiments, conferencing server  603  maintains this tabulated data (e.g., in cache or buffer memory) such that the control circuitry of conferencing server  603  can retrieve the recently generated audio signatures more quickly than audio signatures generated at an earlier time. It should be noted that conferencing server  603  may store any number of conference IDs for various ongoing conferences (e.g., within particular organizations, across multiple organizations, etc.). 
     At  612 , control circuitry (e.g., control circuitry  404  of device  400  or  401  of  FIG.  4   ) may determine that a user (e.g., user  310  of  FIG.  3   ) associated with a device  601  (and not yet joined to the conference) has physically entered a conference room in which one or more devices (among devices  605 ) are joined to a conference established by the conferencing system. For example, techniques discussed in connection with  FIG.  3    may be employed to make such a determination. In some embodiments, the device (e.g., device  311  of  FIG.  3   ) may periodically transmit (e.g., as a push notification or a pull notification) its current location (e.g., GPS coordinates) to conferencing server  603 . The control circuitry of conferencing server  603  may compare such location to the locations and/or IP addresses of one or more devices  605  joined to the conference to determine whether device  601  not yet joined to the conference is in the same physical location (e.g., conference room) as another device (among devices  605 ) joined to the conference. 
     At  614 , upon the control circuitry of device  601  determining that such device is located in the same physical location as one or more devices  605  joined to a conference currently being hosted by conferencing server  603 , the conferencing application causes a microphone (e.g., microphone  113  of  FIG.  1   ) of device  601  to start capturing ambient sound. In some embodiments, the microphone may capture voices from participants in the same physical location as the user and voices of conference participants located in different locations. The microphone of device  601  may capture audio as described in  604  of  FIG.  6   . 
     At  616 , device  601  may transmit (e.g., via I/O path  402  of  FIG.  4   ) the captured ambient audio signal to conferencing server  603 . In some embodiments, device  601  may transmit multiple audio signals to the conferencing server at regular intervals. 
     At  618 , conferencing server  603  may generate an audio signature based on the audio signal received from device  601 . The audio signal may be generated in a similar manner to that of  608  of  FIG.  6   . 
     At  620 , control circuitry of conferencing server  603  may compare the audio signature, generated based on the audio signal received from device  601 , to the audio signatures stored at conferencing server  603 . In some embodiments, the comparison may be performed by control circuitry (e.g., control circuitry  404 ) at both conferencing server  603  and locally at device  601 . As another example, the audio signatures may be stored locally at device  601 , or retrieved via a network (e.g., network  504  of  FIG.  5   ) from the conferencing server for comparison at device  601 . In some embodiments, the conferencing server may retrieve the recently stored audio signatures for comparison at the outset of the comparison process, as such audio signatures may be stored in cache or buffer memory for fast retrieval (and may be more likely to have been generated in an ongoing conference). 
     In some embodiments, the control circuitry compares audio features or characteristics of the generated audio signature to audio features or characteristics of the stored audio signatures (e.g., a base or fundamental frequency of a voice, modulation, amplitude, or other audio characteristics). For example, conferencing server  603  (e.g., using digital signal processor  206  and/or control circuitry) may extract a first peak point with a first frequency and first average power from a first spectrogram of the generated audio signature, and extract a second peak point with a second frequency and second average power from a second spectrogram of a stored audio signature. Conferencing server  603  may determine a frequency difference value between the first frequency and the second frequency and a power difference value between the first average power and the second average power. Based on the comparing, conferencing server  603  may determine whether the generated audio signature matches any of the stored audio signatures. For example, the generated audio signature may be determined to match a stored audio signature if the frequency difference value is under a first threshold (e.g., 100 Hz) and the power difference value is under a second threshold (e.g., 20 dB). In some embodiments, conferencing server  603  may compare respective features vectors which may constitute the audio signature, and determine a match based on whether a similarity between such features vectors is within a certain threshold. 
     In some embodiments, the comparison between the generated audio signature received from device  601  and the stored audio signatures may include audio analysis techniques to determine whether there is match between voices of particular users (e.g., frequency analysis to determine a base frequency and unique harmonic pattern of a particular voice, phoneme analysis to determine an accent of a particular voice, etc.). For example, the control circuitry may determine that there is a match if a similarity score computed by the control circuitry exceeds a predetermined threshold. Phoneme analysis is described in greater detail in Mehra, U.S. Pat. No. 10,621,970, issued Apr. 14, 2020, and Venkataraman et al., U.S. Pat. No. 10,324,940, issued Jun. 18, 2019, which are hereby incorporated by reference herein in their entireties. 
     At  622 , the control circuitry (e.g., of conferencing server  508  of  FIG.  5   ) may determine that there is a match between the audio signature generated based on the audio signal transmitted by device  601  and one or more of the audio signatures transmitted at  606 . For example, certain audio characteristics between the audio signatures may be sufficiently similar (e.g., within a certain threshold, such as after weighting and normalizing is performed) to each other to determine that there is a match. In some embodiments, the control circuitry may determine that there is not a match with audio signatures related to other ongoing conferences prior to determining the matched conference (e.g., conference  105  of  FIG.  1   . Upon determining that there is a match, the control circuitry of conferencing server  603  may transmit the conference ID associated with the conference to device  601 . 
     At  624 , device  601  may be automatically joined to the ongoing conference using the conference ID received from conferencing server  603 . In some embodiments, the user may be automatically joined to the conference (e.g., without further user input). As another example, the control circuitry may generate for presentation a selectable prompt to join the conference, and the user may be joined to the conference when selection of the prompt is received. 
     At  626 , since there may be other devices in the same physical conference room as the user associated with device  601 , the microphone and/or speakers and/or video feed of device  601  may be automatically muted and/or disabled (e.g., without further user input) in order to avoid audio feedback. An icon (e.g., indicator  312  of  FIG.  3    or other indicia) associated with user  601  may be generated (e.g., by control circuitry  404  of  FIG.  4    of the device associated with the user or conferencing server  603 ) for presentation on a display (e.g., projector  304  of  FIG.  3   ) to indicate to other conference participants that the user is now participating in the conference (e.g., via devices  605  in the physical conference room already joined to the conference). Accordingly, irritating audio feedback can be minimized or avoided, and the user may conveniently join the ongoing conference, while the system makes the other participants aware that the user has joined the conference. In some embodiments, upon the user joining the conference, various supplemental features may be made available (e.g., screensharing capabilities, text or chat capabilities, etc.). 
       FIG.  7    shows a processing flow  700  for joining device  701  to a conference, in accordance with some embodiments of this disclosure. It should be noted that process  700  or any step thereof could be performed on, or provided by, any of the devices shown in  FIGS.  4 - 5   . For example, process  700  may be executed by devices  502 ,  505 ,  506  of  FIG.  5    (e.g., via control circuitry  404 ) and/or control circuitry of conferencing server  508 , as instructed by a conferencing application that may be implemented on conferencing device  502 , and/or conferencing device  505  and/or conferencing device  506  and/or conferencing server  508 , such as to distribute control of database management application operations for a target device among multiple devices. In addition, one or more steps of process  700  may be incorporated into or combined with one or more steps of any other process or embodiment (e.g., process  600  of  FIG.  6   ). 
     At  702 , conferencing server  703  may establish a conference via a communication network (e.g., communication network  504  of  FIG.  5   ) in a similar manner to that of  602  of  FIG.  6   . At  704 , a microphone of each of devices  705  joined to the conference may capture audio signals of voices of users in the conference, in a similar manner to  604  of  FIG.  6   . 
     At  706 , one or more devices  705  (e.g., devices  502 ,  505 ,  506  of  FIG.  5   ) joined to the conference may generate (e.g., via control circuitry  404  of  FIG.  4   ) respective audio signatures based on the audio signals captured at the respective devices  705 . Each of the devices  705  may generate the audio signatures in a similar manner to that of  608  of  FIG.  6   , and in accordance with the techniques discussed in connection with  FIG.  2   . 
     At  708 , each of devices  705  may transmit (e.g., via I/O path  402  of  FIG.  4   ) the generated audio signatures to conferencing server  703 . In some embodiments, the generated audio signatures may be transmitted from each of the devices  705  joined to the conference at the same time, or at staggered times. For example, the generated audio signatures may be transmitted to conferencing server  703  each time the audio is sampled by the respective devices  705  (e.g., upon completion of generation of the audio signatures). 
     At  710 , conferencing server  703  may receive (e.g., via I/O path  402  of  FIG.  4   ) the generated audio signatures, and control circuitry of the conferencing server (e.g., server  508  of  FIG.  5   ) may store (e.g., in storage  408  of  FIG.  4   ) the generated audio signatures in connection with the conference ID associated with the conference. In addition to the conference ID, the generated signatures may be associated and/or tabulated with device IDs respectively associated with devices  705  joined to the conference, and a timestamp associated with each audio signature. In some embodiments, conferencing server  703  maintains this tabulated data (e.g., in cache or buffer memory) such that the control circuitry of conferencing server  703  can retrieve the recently generated audio signatures more quickly than audio signatures generated at an earlier time. It should be noted that conferencing server  703  may store any number of conference IDs for various ongoing conferences (e.g., within particular organizations, across multiple organizations, etc.). 
     At  712 , control circuitry (e.g., control circuitry  404  of device  400  or  401  of  FIG.  4   ) may determine that a user (e.g., user  311  of  FIG.  3   ) associated with device  701  has physically entered a conference room in which one or more devices are joined to a conference established by the conferencing system. For example, techniques discussed in connection with  FIG.  3    may be employed to make such a determination, and in a similar manner to that of  612  of  FIG.  6   . 
     At  714 , upon control circuitry (e.g., control circuitry  404  of  FIG.  4   ) of the device  701  determining that such device is located in the same physical location as one or more devices joined to a conference currently being hosted by conferencing server  703 , the conferencing application causes a microphone (e.g., microphone  113  of  FIG.  1   ) of the device to start capturing ambient sound. In some embodiments, the microphone may capture voices from participants in the same physical location as the user and voices of conference participants located in different locations. The microphone of the device may capture audio as described in connection with  604  of  FIG.  6   . 
     At  716 , the device  701  may generate (e.g., via control circuitry  404  of  FIG.  4   ) one or more audio signatures based on the audio signals captured at the device. Such device may generate the audio signatures in a similar manner to  608  of  FIG.  6   , and such as in accordance with the techniques discussed in connection with  FIG.  2   . 
     At  718 , the device may transmit (e.g., via I/O path  402  of  FIG.  4   ) the generated audio signature to conferencing server  703 . In some embodiments, the device may transmit multiple audio signals to conferencing server  703  at regular intervals. 
     At  720 , control circuitry (e.g., of the conferencing server) may compare one or more audio signatures received from the device  701  to the audio signatures stored at the conferencing server. Such comparison may be performed in a similar manner to  620  of  FIG.  6   . 
     At  722 , the control circuitry (e.g., of conferencing server  508  of  FIG.  5   ) may determine that there is a match between the audio signature generated by the device  701  and the audio signatures generated by the devices already joined to the conference (e.g., conference  301  of  FIG.  3   ). Upon determining that there is a match, the control circuitry of conferencing server  703  may transmit the conference ID associated with the conference to the device  701 . 
     At  724 , the device  701  may be automatically joined to the ongoing conference using the conference ID received from conferencing server  703 . In some embodiments, the user may be automatically joined to the conference (e.g., without further user input). As another example, the control circuitry may generate for presentation a selectable prompt to join the conference, and the user may be joined to the conference when selection of the prompt is received. 
     At  726 , since there may be other devices (among devices  705 ) in the same physical conference room as the user associated with device  701  now joined to the conference, the microphone and/or speakers and/or video feed of such device may be automatically muted and/or disabled (e.g., without further user input) in order to avoid audio feedback. An icon (e.g., indicator  312  or other indicia) associated with the user may be generated (e.g., by control circuitry  404  of the device  701  or conferencing server  703 ) for presentation on a display (e.g., projector  304  of  FIG.  3   ) to indicate to other conference participants that the user is now participating in the conference (e.g., via a device in the physical conference room already joined to the conference). Accordingly, irritating audio feedback can be minimized or avoided, and the user may conveniently join the ongoing conference, while the system makes the other participants aware that the user has joined the conference. In some embodiments, upon the user joining the conference, various supplemental features may be made available (e.g., screenshare, meeting chat, etc.). 
     Those of skill in the art would appreciate that the various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the embodiments disclosed herein may be implemented with electronic hardware, computer software, or combinations of both. To illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software may depend upon the particular application and design constraints imposed on the overall system. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention. Moreover, method steps may be interchanged without departing from the scope of the invention. 
     The various illustrative logical blocks, modules, and circuits described in connection with the embodiments disclosed herein may be implemented or performed with a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in the alternative, the processor as described herein may be any conventional processor, controller, microcontroller, or state machine. A processor also may be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration. 
     The steps of a method or algorithm described in connection with the embodiments disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium may be coupled to the processor such that the processor reads information from, and writes information to, the storage medium. In the alternative, the storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC. The ASIC may reside in a user terminal. In the alternative, the processor and the storage medium may reside as discrete components in a user terminal. 
     Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein. Thus, one of ordinary skill in the art would understand that the invention is not to be limited by the foregoing illustrative details, but rather is to be defined by the appended claims.