Abstract:
A system to allow a conferee defined as a nuisance source to respond to an automatic nuisance decision of a Multipoint Control Unit is disclosed. For example, a conferee placing a conference on hold may generate on hold music, which may be identified by a nuisance detector. The nuisance detector sends an indication of the nuisance condition to a control unit in the MCU. The control unit mutes the signal coming from this conferee and sends an Interactive Voice Response (IVR) message to the conferee. The message may inform the conferee that he has been muted and requests the conferee for example to press one of a plurality of touch tone keys depending on his situation. For instance, the conferee can select particular keys if he is returning from the hold condition, if he is experiencing a noisy line/environment and needs to reduce the sensitivity of the nuisance detector algorithm, or if he wishes to disable the nuisance detector algorithm.

Description:
BACKGROUND 
   1. Field of Invention 
   The present invention relates to the field of multipoint audio/video conferences, and more particularly to improving the quality of the conference by reducing nuisance signals. 
   2. Description of Background Art 
   Multipoint conferences of audio, video, and/or multimedia involve communication between more than two participants. Commonly, conference calls may be established over a communications network, such as the Public Switched Telephone Network (“PSTN”), an Integrated Services Digital Network (ISDN), an Internet Protocol (IP) network, etc. The network contains Multipoint Control Units (MCU) and/or audio bridges that route and compose the communications of the participants in the call. The operation of MCUs and audio bridges are well known to those skilled in the art, and exemplary audio bridges are disclosed in U.S. patent application Ser. Nos. 10/072,081 and 10/144,561, the contents of which are incorporated herein by reference. It should be noted that the terms “MCU” and “audio bridge” may be used interchangeably herein. 
   A common MCU may receive audio signals from a plurality of conferees, analyze the signals and create control information such as, but not limited to, VAD (Voice Activity Detection), signal energy, and signal quality measures. Based on the control information, decisions may be made regarding whose signals will be mixed and distributed among the other conferees, or whose signal will be muted due to a conclusion that the signal is below acceptable quality. Un-Acceptable Signal (UAS) is an objective criteria and may depend on the type of the conference. Exemplary criteria may be non-voice signals such as: music, DTMF, background noise, etc. The terms “noisy signal,” “nuisance,” and “UAS” may be used interchangeably, and the term “nuisance” may denote all of these terms. 
   There are known methods for generating information regarding signal energy, VAD, and quality. Exemplary algorithms for creating such information are disclosed in G723.1 (used in Annex A for the same standard); G729.1 Annex B; and GSM AMR (GSM 06.71) using the VAD algorithm GSM 06.94. A simple algorithm for a Nuisance Detector (ND) may define a signal as “nuisance” when the signal energy (SE) is above a certain level, while the VAD indicates that the signal is not voice. 
   The quality of a conference depends on the automatic decisions made by such methods. For example, a sensitive ND algorithm may disconnect a valid participant, while a less sensitive algorithm may add a noisy connection to the conference mix, i.e., the composed audio signal of the selected conferees. The selection is based on the conference setup parameters and on the automatic decisions made from analyzing the signals of the current speakers. There are cases where an automatic decision may frequently reach an erroneous result. For example, in the case where a conferee places the conference call on hold and accepts another call, the private branch exchange (PBX) to which the conferee is connected may play “music on hold” over the conferee&#39;s connection, disturbing the rest of the conference&#39;s participants. “Music on hold” may be music, broadcast radio, advertising or other signals to the on-hold conferee. Generally “music on hold” may have the same properties as speech and therefore it may pass the criteria of common VAD and/or ND algorithms and therefore may erroneously be transmitted to the other parties in the conference. On the other hand, a sensitive ND that is not properly tuned to the connection quality of a certain conferee may harm/disconnect a valid conferee. Therefore, it is difficult to pre-tune the ND algorithm to different conferee&#39;s conditions. 
   Thus, it is evident that current technologies of automatic nuisance detection in audio/video conferencing may make wrong decisions that reduce the quality of the conference. Therefore, there is a need in the art for a new nuisance detection method to overcome these deficiencies. 
   SUMMARY OF THE INVENTION 
   Systems according to the present invention solve the above-described problem by providing a path to a conferee defined as a nuisance source by the MCU to respond to this determination and to correct or adjust/tune the ND according to his/her audio signal. 
   For example, in a telephone conference, in which at least one of the conferees may be connected to the conference via a PBX, the conferee may place the conference on hold, forcing a nuisance signal over the connection to the conference. The ND may then identify this connection as a nuisance connection and send this indication to an exemplary control unit in the MCU. The control unit upon receiving an indication that the conferee channel is a nuisance may mute the signal coming from this conferee. Then the exemplary controller may place an Interactive Voice Response (IVR) message over the audio signal to the conferee. An exemplary message may inform the conferee that he has been muted and request the conferee to press one of the touch tone keys, for instance, ‘1’ if he is returning from being on hold, ‘3’ if the conferee is using/within a noisy line/environment, or ‘5’ to disable the ND algorithm, etc., and as explained further below. 
   If a response is not received from the conferee, the message may continue for a certain period or for the rest of the conference. By contrast, if an appropriate key has been pressed, the system according to the present invention may act as follows. In an exemplary embodiment, if ‘1’ is pressed, muting of the conferee is canceled and the conferee can be heard. If ‘3’ is pressed, the sensitivity of the ND algorithm is reduced, allowing the control unit to enable the conferee to be heard in the conference while keeping a record of this adjustment. If ‘5’ is pressed, the ND algorithm may be disabled to allow the nuisance conferee to be connected without condition. 
   Other exemplary embodiments may request, using an IVR message, from another conferee, for example the chairman of the conference, to decide whether to mute the noisy conferee or not. 
   Other exemplary embodiments may place a noisy conferee in push to talk (PTT) operation, thereby instructing the noisy conferee, using an IVR message, to momentarily push any one of the keys each time he wishes to talk and to push again when he is finished speaking. 
   In general, systems according to the present invention may use means other than DTMF feedback to allow the conferee to respond, such as but not limited to, voice recognition, network control signals such as ISDN ‘D’ channel, control packets over IP communication, etc. 
   Thus, systems according to the present invention advantageously offer an improved algorithm that handles nuisances in conferences by requesting feedback from the nuisance conferees. The feedback from the noisy conferee may correct the automatic decision and therefore improve the quality of the conference. 
   Other features and advantages of the present invention will become apparent upon reading the following detailed description of the embodiments with the accompanying drawings and appended claims. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1A  is a block diagram showing an exemplary conference environment; 
       FIG. 1B  is a block diagram of an embodiment according to the invention, including a general description of an audio unit in an MCU; 
       FIG. 2A  is a block diagram of an ND that operates according to an exemplary embodiment of the present invention; and 
       FIG. 2B  is a flow diagram showing the steps of an exemplary method for handling of a nuisance participant. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Turning now to the figures in which like numerals represent like elements throughout the several views, exemplary embodiments of the present invention are described. For convenience, only some elements of the same group may be labeled with numerals. The purpose of the drawings is to describe exemplary embodiments and not for production. Therefore features shown in the figures are chosen for convenience and clarity of presentation only. 
     FIG. 1A  is an exemplary block diagram illustrating a general description of a conference environment  100 . The conference environment may have endpoints  1110   aa - nk , an operator  1115 , multimedia communications  1120   aa - nk  and  1122   a - k , networks  1130   a - k , and a Multimedia Conference Control Unit (MCCU)  1140 . In one exemplary embodiment, the MCCU  1140  may include at least one Network Interface (NI)  1142 , a Compressed Audio Common Interface (CACI)  110 , an audio unit  1160 , a Management and Control System (MCS)  1170 , control signals  1174 , a host  1200 , and a video unit  1300 . Other exemplary embodiments may not have a video section and may be used for audio conferences only. MCCU  1140  may handle a nuisance conferee by using embodiments according to the present invention. 
   The pluralities of endpoints  1110   aa - nk  are connected via the plurality of networks  1130   a - k  to the MCCU  1140 . The MCCU  1140  may be an MCU, or an audio only multipoint control unit (an audio bridge), for example. The MCCU  1140  and/or some or all of its components are logical units that may be implemented by hardware and/or software. The MCS  1170  may be a control module and may be a logical unit that controls the operation of the MCCU  1140 . 
   An endpoint is a terminal on a network capable of providing one-way or two-way audio and/or visual communication with other terminals or with the MCCU  1440 . The information communicated between the terminals and/or the MCCU  1440  may include control signals, indicators, audio information, video information, and data. A terminal may provide any combination of several different types of inputs and/or outputs, such as speech only, speech and data, a combination of speech and video, or a combination of speech, data, and video. In the case of audio conference, the endpoint may be a common telephone, cellular telephone, etc. 
   The NI  1142  receives multimedia communications  1122   a - k  via networks  1130   a - k  and multimedia communications  1120   aa - nk  from the endpoints  1110   aa - nk , and processes the media communication according to communication standards that are used by each type of network, such as, but not limited to, H.323, H.321, H.324, H.324M, H.320, SIP, ISDN, PSTN, etc. The NI  1142  then delivers compressed audio, compressed video, compressed data, and control streams to appropriate logical modules in the MCCU  1140 . Some communication standards require that the process of the NI  1142  include demultiplexing the incoming multimedia communication into compressed audio, compressed video, compressed data and control streams. In the opposite direction, the NI  1142  receives the separate streams from the various units (e.g., the MCS  1170 , audio unit  1160 , and/or video unit  1300 ) and processes the streams according to the appropriate communication standard. The NI  1142  then transmits the streams to the appropriate network  1130   a - k.    
   The audio unit  1160  receives the compressed audio streams of the plurality of endpoints  1110   aa - nk  via NI  1142  and CACI  110 , processes the audio streams, mixes the relevant audio streams, and sends the compressed mixed signal via the Compressed Audio Common Interface (CACI)  110  and the NI  1142  to the endpoints  1110   aa - nk . Audio unit  1160  may be a logical unit and is described below with respect to  FIG. 1B . 
   The video unit  1300  may be a logical unit that receives and sends compressed video streams. The video unit  1300  includes at least one video input module that handles an input portion of a video stream  1302  from a participating endpoint and at least one video output module that generates a composed compressed video output stream that is sent via Compressed Video Common Interface (CVCI)  1302  to NI  1142  and from there to the designated endpoints  1110   aa - nk . An exemplary operation of such a video unit is described in U.S. Pat. No. 6,300,973, which is incorporated herein by reference. The video unit is not mandatory for the operation of the present invention, as the present invention may be used by a MCCU that does not have a video unit, such as an audio bridge. 
   Preferably, the host  1200  communicates with the operator  1115  of the MCCU  1140 , where the operator  1115  may have an operator&#39;s station for communicating with the host  1200 . The host  1200  controls the MCCU  1140  via the MCS  1170  according to instructions from the operator  1115 . However, the operator  1115  is not mandatory, as the MCCU may operate automatically without an operator. 
     FIG. 1B  is an exemplary block diagram of an embodiment of a general audio unit  1160  using an embodiment of the present invention, as well as other structures related to the audio unit. As shown, the audio unit  1160  couples to a Compressed Audio Common Interface (CACI)  110 , and a control bus  135  in communication with the MCS  1170 . The audio unit  1160  has compressed signals  115  and  117  sent to and from it by the CACI  110 , a codec  120 , decoded information  126 , a mixed output  128 , a Decoded Audio Common Interface (DACI)  140 , and a bridge  150 . The codec  120  includes a decoder  122  and an encoder  124 , while the bridge  150  includes Analyze and Enhance (A&amp;E) units  152 , information signals  153 , a control unit  154 , an IVR unit  154   a , a switch  156 , control signals  157 , selected signals  159 , a mixer  160 , and mixed signals  161 . 
     FIG. 1B  describes the flow of audio streams in one example of the present invention. Compressed audio streams from all endpoints connected to the MCCU are transferred over the Compressed Audio Common Interface (CACI)  110 . The MCS  1170  may allocate a codec  120  to each one of the endpoints  1110   aa - nk  ( FIG. 1A ). The CACI  110  carries signals to and from endpoints  1110   aa - nk . For example, the compressed signal  115  from one of the endpoints  1110   aa - nk  is routed through the CACI  110  to the decoder  122  in the codec  120 , which was previously allocated to that endpoint by the MCS  1170  via control bus  135 . The decoder  122  may be a logical unit comprised of software and/or hardware, and may decode a compressed audio stream  115  in accordance with communication standards such as, but not limited to, G.711, G.723.1, G.728, G.729, MPEG or relay uncompressed audio. The decoder  122  then broadcasts the decoded signal  126  over the Decoded Audio Common Interface (DACI)  140 . The DACI  140  is a bus that may have broadcasting capabilities, and may be implemented for example by Time Division Multiplexing (TDM), Asynchronous Transmission Mode (ATM), Local Area Network (LAN), wireless technology, or shared memory, or any combination of these. An appropriate bridge  150  may then grab the decoded signal from the DACI  140  and may analyze, enhance, and/or mix the decoded signal and return the output  161  to the DACI  140 . 
   The encoder  124  may also be a logical unit, and generally the encoder  124  compresses the output  128  of the appropriate bridge  150  to form a compressed audio stream or signal  117  based on an appropriate communication standard such as, but not limited to, G.711, G.723.1, G.728, G.729, and/or Motion Picture Expert Group (MPEG). 
   The MCS  1170  may use a database that holds the connection parameters (e.g., codecs and bridges, etc.) and the connection status (e.g., normal, muted, etc.) of each endpoint (participant) that is currently connected to the MCCU, and for every conference that is currently managed by the MCCU. The Mute (M) connection status means that the participant cannot be heard in the conference. The Normal (N) connection status means that the participant can be heard and can listen to the conference, etc. According to the database, the MCS  1170  programs one or more bridges  150  to grab from the DACI  140  the decoded signals of all the participants associated with a conference assigned to those bridges  150 . 
   The decoded output  126  of any codec  120  can be grabbed by more than one bridge  150 , allowing the participants to be associated with more than one conference. The decoded streams from the decoders  122  on the DACI  140  may be grabbed by the bridge  150  and then analyzed and enhanced by the A&amp;E unit  152 . The A&amp;E unit  152  may be a logical unit, and may include a set of algorithms for analyzing an audio stream of a participant and/or enhancing its quality, such as, but not limited to, International Telecommunications Union (ITU) G.165 (echo canceling), Dual Tone Multi-Frequency (DTMF) detection, DTMF suppression, signal energy analysis, or nuisance signal analysis, and may include a Voice Activity Detector (VAD). 
   The bridge  150  may have one or more A&amp;E units  152 . Each A&amp;E unit  152  is assigned to a single participant and is programmed according to the connection status of that participant in the conference. The control unit  154  controls a conference, and receives all signals from the A&amp;E unit  152  to select the participants that will be routed via switch  156  to the mixer  160 . The control unit  154  may implement an exemplary method of the present invention, described in further detail below with respect to  FIGS. 2A &amp; 2B , by utilizing the analysis signals  153  coming from A&amp;E units  152  and controlling the IVR module  154   a  and switch  156  appropriately. A single bridge  150  may serve a conference, a group of conferees or a single conferee. In the last two cases, more than one bridge  150  may be involved in the conference. 
   The mixer  160  receives the enhanced streams from all of the selected participants and/or the signal from IVR  154   a , and supplies each participant with an uncompressed mixed audio stream of the selected participants and/or the signal IVR  154   a . Mixer  160  may supply more than one stream  161 , each stream having a different mix. 
   As just noted, signals  153  from the A&amp;E unit  152  are sent to the control unit  154  and the enhanced decoded audio signals  155  are sent from the A&amp;E units  152  to the switch unit  156 . The switch unit  156  is a selector that receives the decoded streams from all the participants in a conference as well as the IVR unit  154   a  and transfers the selected streams to mixer  160 . The selection is based on the decisions of the control unit  154 . The decisions of the control unit  154 , in turn, are based on received commands from the MCS  1170  (which define the connection status of the participants in the conference that are assigned to the bridge  150 ) and the information signal  153  from the A&amp;E unit  152 . The control unit  154  controls, via control signals  157 , the switch  156  and the mixer  160 . For example, in a case where a participant&#39;s connection status is Normal (N), the A&amp;E unit  152  associated with that participant may indicate that the voice signal meets a certain criteria such as set forth by VAD, for example, that the signal energy level is above a certain value. Then, the control unit  154  via switch  156  selects the output  155  of the A&amp;E unit  152  assigned to the participant as one of the inputs to the mixer  160 . 
   In another case, the A&amp;E unit  152  associated with a participant may indicate to the control unit  154  that the participant signal is nuisance, in which case the control unit  154  may initiate an exemplary embodiment of the present invention as illustrated in  FIGS. 2A &amp; 2B , discussed below. Generally, the control unit  154  may instruct the switch  156  to remove the audio signal  155  that belongs to this nuisance conferee from the mixer  160  of all the other participants, placing the nuisance conferee in Mute state. In parallel, the control unit  154  may instruct switch  156  to select the IVR  154   a  output as the input to the mixer of the nuisance participant. 
   In an alternate embodiment (not shown in the drawings) the output of the IVR unit may be delivered directly to the DACI, in which case the encoder of the nuisance conferee is instructed to grab the IVR&#39;s signal from the DACI instead of the output of the appropriate mixer. 
   The mixer  160  mixes the selected audio signals to form the mixed signals  161 , and broadcasts the mixed signals  161  over the DACI  140 . Some embodiments of the bridge  150  have the capability of eliminating the voice of a speaker from the mixed signal that is directed to the endpoint of that speaker. Control unit  154  may update the MCS  1170  with the new situation of the nuisance conferee. 
   The MCS  1170 , based on the connection status stored in the database, commands one or more codecs  120  to grab the mixed output  128  from the DACI  140 , after which the encoder  124  encodes the decoded signal from the appropriate bridge  150 , and sends the compressed signal  117  via the CACI  110  to the appropriate participant. 
   The codecs  120  and the bridges  150  may be implemented by Digital Signal Processors (DSPs) such as, but not limited to, Texas Instruments DSP TMS320C31. One DSP can include more than one unit, i.e., more than one codec and/or bridge. In the above example, the codec  120  handles a single participant&#39;s audio signal, and the bridge  150  handles one conference or part of a conference. 
   Referring now to  FIG. 2A , which is a block diagram of an exemplary embodiment, Nuisance Detector (ND)  2020  is an adjustable ND that may be part of the A&amp;E unit  152  of  FIG. 1B . In the exemplary embodiment, each ND  2020  unit is associated with a single conferee. The ND  2020  uses a nuisance algorithm with a current set up and a current parameters set. The ND  2020  sends indications to control unit  154  ( FIG. 1B ). The control unit  154 , based on these indications and existing control information, reaches decisions  2025 . According to those decisions, the control unit  154  sends control instructions  2030  that influence the audio stream to the appropriate conferee. The control instructions may be sent to the mixer  160  or to switch  156  ( FIG. 1B ). In parallel, an IVR message  2040  may be sent to the nuisance conferee requesting feedback. Upon receiving feedback from the conferee, the control unit  154  tunes/adjusts the ND by updating its parameters. 
     FIG. 2B  is a flowchart depicting an exemplary method  200  according to the present invention for handling a nuisance conferee by the exemplary control unit  154  ( FIG. 1B ). Upon receiving a ND indication from a certain A&amp;E unit  152 , control unit  154  starts the nuisance handling task ( 210 ). First, to eliminate the nuisance from the rest of the participants, control unit  154  places the nuisance participant into a Mute state ( 215 ). As part of this step, the control unit  154  instructs switch  156  to prevent the audio signals  155  that belong to this nuisance conferee from the appropriate mixer  160 . 
   The control unit then instructs the IVR  154   a  to send a “Mute” message to the nuisance conferee ( 224 ). In parallel, and for as long as the IVR message is active, the switch  156  is instructed to select the input of the IVR unit  154   a  as the only input to a mixer  160  that is associated with the nuisance conferee. An exemplary “Mute” message may be: “Please be aware that you have been muted. Please press ‘1’ upon returning from ‘Hold’. Please press ‘3’ if you were not in hold.” 
   Other exemplary embodiments may offer other or additional options. For example, an additional option may be added to allow the ND algorithm to be disabled, such as: “Please press ‘5’ to disable the ND algorithm,” etc. 
   At the end of the message the control unit may wait for a period ‘T 1 ’ ( 226 ). Period ‘T 1 ’ may be in the range of a few hundreds milliseconds to several seconds, and exemplary values of ‘T 1 ’ may be 800 milliseconds, 2 seconds, etc. At the end of the waiting period, the control unit verifies  230  whether a DTMF signal has been identified by the A&amp;E unit  152  that is associated with the nuisance conferee. If no DTMF signal has been received, which may reflect that the nuisance conferee is not listening to the conference, then the control unit returns to step  224  and continues the mute decision. Such a case may happen if the nuisance conferee has put the conference call on hold or has been disconnected, in which case there is no harm to either the nuisance conferee or to the rest of the participants. The loop comprising steps  224 ,  226  and  230  may continue until a DTMF signal is received. If no DTMF signal is received or a DTMF signal other than ‘1,’ ‘3,’ or ‘5’ has been received, the loop may continue until the end of the conference. Other embodiments may add a counter that counts the number of cycles and may disconnect the nuisance conferee after a certain number of cycles. 
   If a DTMF signal has been received such as a ‘1,’ indicating that the nuisance conferee has returned to the conference, then control unit  154  ( FIG. 1B ) instructs  234  the appropriate switch  156  to enable the audio signal  155  associated with the nuisance conferee and to disconnect the IVR unit  154   a  from the appropriate mixer. Then the task is terminated  236 . 
   If a DTMF signal has been received such as a ‘3,’ indicating that the nuisance conferee is listening to the conference, the received ND indication may be due to a noisy connection or noisy environment. Then, the level of the threshold of the ND  2020  is increased ( 238 ), which reduces the sensitivity to noise. Thus, the present invention may set the initial threshold level to a low level, but based on the feedback from a nuisance conferee, the setup can be adjusted to suit the current connection. 
   Different embodiments of the present invention may utilize different methods for increasing the threshold level. One exemplary method may increase the level by a certain percentage from the current level each time, 10%, 30%, and 50%, for example. Other methods may use a fixed value increase, or may change the values according to the value of a counter (“Cnt”), etc. In embodiments using a counter, the counter is reset during the initiation of the conference and the value of the counter is increased by one each time that the conferee has been identified as a nuisance, as specifically shown at step  238  in  FIG. 2B . 
   At step  240 , a decision is made whether the nuisance conferee is a disturbing one. If the nuisance conferee is defined as a disturbing conferee, the Mute state of the conferee will be kept for the rest of the conference. If not, the Mute state may be canceled. An exemplary embodiment may compare the new ND level to a predefined maximum level, “Max” ( 240 ). The Max value is a parameter that may be set during the set up of the conference or may be a default value above which noise is deemed disturbing, such that it is deemed better to permanently mute the nuisance conferee. Other embodiments may make a decision based on the value of the counter (Cnt), such that if the value of the counter has been increased a certain number of times, it indicates that the connection and the conferee are disturbing. 
   If the connection is not deemed a disturbing connection at step  240 , for example because the ND level is below Max, then the mute state is canceled  234 , and the task is terminated  236 . The task may be restarted if a new ND indication is received, and this time the value of the counter will be other than zero. 
   If the connection is deemed a disturbing connection at step  240 , for example because the ND level is above Max, then the exemplary embodiment of the present invention may retain the mute state of the nuisance conferee and allow the nuisance conferee to only listen to the conference. At step  242 , the IVR module  154   a  ( FIG. 1B ) is instructed to send a message indicating that the conferee has been deemed a disturbance, such as: “Please be aware that you have been muted. In case you want to speak, please dial in again.” 
   Other embodiments may offer the conferee the option to disconnect the current connection and re-try again, or may request human assistance to decide how to proceed with the nuisance conferee. 
   If a DTMF signal has been received such as a ‘5,’ this indicates that the nuisance conferee has requested to disable the ND  2020 . Such a request may be appropriate when the involvement of this conferee is crucial in this conference and he/she must be heard even though the connection is noisy. In such a case, the control unit disables the ND  2020  and cancels the mute condition of the nuisance conferee ( 232 ). 
   Alternate embodiments of the present invention may use feedback other than DTMF tones to allow the conferee to respond, such as but not limited to, voice recognition, network control signals such as ISDN ‘D’ channel signals, control packets over IP communication, etc. 
   The present invention may handle more that one nuisance conferee. For each nuisance conferee, a dedicated task such as that disclosed herein may be initiated. 
   In this application the words “unit” and “module” are used interchangeably. Anything designated as a unit or module may be a stand-alone unit or a specialized module. A unit or a module may be modular or have modular aspects allowing it to be easily removed and replaced with another similar unit or module. Each unit or module may comprise software, hardware, or firmware, and combinations of these. 
   Embodiments of this invention will improve the quality of a conference by handling a nuisance conferee automatically, and by allowing feedback from the nuisance conferee that improves the automatic decision. Moreover, the process is transparent to the rest of the conferees. 
   The present invention has been described using detailed descriptions of embodiments thereof that are provided by way of example and are not intended to limit the scope of the invention. The described embodiments comprise different features, not all of which are required in all embodiments of the invention. Some embodiments of the present invention utilize only some of the features or possible combinations of the features. Variations of embodiments of the present invention that are described and embodiments of the present invention comprising different combinations of features noted in the described embodiments will occur to persons of the art. The scope of the invention is limited only by the following claims.