Abstract:
A method and apparatus for identifying voice mail messages uses speaker identification to identify a voice mail message. The method preferably includes comparing the voice mail message to existing voice samples in order to determine a matching coefficient. If the matching coefficient is within an allowed range, the voice mail message is categorized as a matched voice mail message and a name indicator is coupled to the voice mail message. The apparatus includes a user interface, a processing unit, and a storage media. The user interface receives the voice mail message and allows access to the voice mail message by a voice mail recipient. The processing unit compares the voice mail message to the existing voice samples, determines the matching coefficient, and assigns the name indicator. The storage media stores the voice mail message.

Description:
FIELD OF THE INVENTION 
     This invention relates to the field of voice mail messaging. More particularly, this invention relates to the field of identifying voice mail messages. 
     BACKGROUND OF THE INVENTION 
     A voice mail system of the prior art is illustrated in FIG.  1 . The voice mail system  10  includes a PBX (Private Branch eXchange) telephone system  12 , a voice mail server  14 , and a LAN (Local Area Network)  16 . Incoming telephone lines  18  are coupled to the PBX telephone system  12 . The PBX telephone system  12  is coupled to the voice mail server. The voice mail server  14  is coupled to the LAN. 
     The PBX telephone system  12  includes a PBX  24  and first, second, third, and fourth telephones,  26 ,  28 ,  30 , and  32 . The first, second, third, and fourth telephones,  26 ,  28 ,  30 , and  32  are coupled to the PBX  24 . The PBX telephone system  12  can include more or less telephones than the first, second, third, and fourth telephones,  26 ,  28 ,  30 , and  32 . The PBX  24  is coupled to the voice mail server  14 . 
     The LAN  16  includes first and second file servers,  34  and  36 , and first, second, third, and fourth computers,  38 ,  40 ,  42 , and  44 . The first and second file servers,  34  and  36 , and the first, second, third, and fourth computers,  38 ,  40 ,  42 , and  44 , are coupled together by computer network cables. The LAN can include more or less file servers and more or less computers. 
     In operation, a telephone caller will place a telephone call. The PBX  24  routes the telephone call to an appropriate telephone, for example the first telephone  26 . If the telephone call is unanswered, the telephone caller will be prompted to leave a voice mail message for a voice mail recipient. The voice mail message is received by the voice mail server  14 . The voice mail server  14  routes the voice mail message to an appropriate file server, for example the first file server  34 , for storage. 
     The voice mail recipient retrieves the voice mail message by accessing the voice mail server  14  via the first, second, third, or fourth telephones,  26 ,  28 ,  30 , or  32 , via the external telephone, or via the first, second, third, or fourth computers,  38 ,  40 ,  42 , or  44 . When accessing the voice mail server  14  via the first, second, third, or fourth telephone,  26 ,  28 ,  30 , or  32 , or via the external telephone, the voice mail recipient will typically retrieve the voice mail message using touch-tone telephone keys and a voice prompted menu system. When accessing the voice mail message using the first, second, third, or fourth computers,  38 ,  40 ,  42 , or  44 , the voice mail recipient uses a voice mail GUI (Graphical User Interface), and a speaker coupled to the first, second, third, or fourth computer,  38 ,  40 ,  42 , or  44 . The speaker can be part of the first, second, third, or fourth telephone,  26 ,  28 ,  30 , or  32 , or can be a separate speaker. 
     The voice mail GUI of the prior art is illustrated in FIG.  2 . The voice mail GUI  46  includes a title bar  48 , a drop-down menu bar  50 , an icon menu bar  52 , a system control bar  54 , a folder list  56 , a voice mail message list  58 , and a message list status  60 . The title bar  48  indicates a software title, which in this case is “Voice Mail Software,” a generic title. The title bar  48  also indicates a voice mail recipient name, which in this case is “Chris Hunter,” and a telephone extension number, which in this case is “4327.” The drop-down menu bar  50 , the icon menu bar  52 , and the system control bar  54  are typical of GUI&#39;s in general. 
     The folder list  56  includes an inbox  64 , which indicates that there are six voice mail messages in the inbox  64 . Since the inbox  64  is highlighted, the voice mail message list  58  displays the six voice mail messages in the inbox  64 . The message list status  60  indicates that the six voice mail message are in the inbox  64  and that one voice mail message  66  is highlighted. The voice mail message list  58  of the prior art will identify a telephone caller name if the telephone caller is calling from an internal telephone, for example the second telephone  28 , using ANI (Automatic Number Identification). The ANI is integral to the voice mail server  14 . The voice mail server  14  is programmed with either the telephone caller name, a location, such as “library,” or a telephone extension number for the first, second, third, and fourth telephones,  26 ,  28 ,  30 , and  32 . 
     The voice mail message list  58  of the prior art will indicate a caller telephone number or the telephone caller name if ICLID (InComing Line IDentification) is present. The telephone caller name is indicated if the voice mail server  14  has been programmed to indicate the telephone caller name rather than the caller telephone number for the ICLID. 
     It would be advantageous to be able to identify the telephone caller name for the voice mail message when the ANI or the ICLID is not present. Further, it would be advantageous to be able to identify the voice mail message without relying on a specific telephone number or a specific telephone extension number for the telephone caller. 
     What is needed is a method of identifying the voice mail message when the ANI or the ICLID is not present. What is also needed is a method of identifying the voice mail message that identifies the telephone caller rather than the specific telephone number or the specific telephone extension that is being used by the telephone caller. 
     SUMMARY OF THE INVENTION 
     The present invention is a method and apparatus for identifying voice mail messages using speaker identification. The method preferably includes comparing a voice mail message to existing voice samples in order to determine a matching coefficient. If the matching coefficient is within an allowed range, the voice mail message is categorized as a matched voice mail message and a name indicator is coupled to the voice mail message. 
     The apparatus includes a user interface, a processing unit, and a storage media. The user interface is coupled to the processing unit and the processing unit is coupled to the storage media. The user interface receives the voice mail message and allows access to the voice mail message by a voice mail recipient. The processing unit compares the voice mail message to the existing voice samples, determines the matching coefficient, and assigns the name indicator. The storage media stores the voice mail message. 
     An embodiment of the invention includes a computer readable medium bearing computer program code. The computer program code includes means for identifying the voice mail message using the speaker identification. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 illustrates a voice mail system of the prior art. 
     FIG. 2 illustrates a voice mail GUI (Graphical User Interface) of the prior art. 
     FIG. 3 illustrates the preferred method of identifying voice mail messages of the present invention. 
     FIG. 4 illustrates the preferred speaker identification method of the present invention. 
     FIG. 5 illustrates the preferred apparatus for identifying voice mail messages of the present invention. 
     FIG. 6 illustrates the preferred method of generating speaker templates. 
     FIG. 7 illustrates a voice mail GUI of the present invention. 
     FIG. 8 illustrates an alternative method of identifying voice mail messages of the present invention. 
     FIG. 9 illustrates an alternative speaker identification method of the present invention. 
     FIG. 10 illustrates an alternative voice mail GUI of the present invention. 
     FIG. 11 illustrates a name indicator correction method of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The preferred voice mail identification method of the present invention is illustrated in FIG.  3 . The preferred voice mail identification method  100  includes first, second, and third steps,  102 ,  104 , and  106 . In the first step  102 , a voice mail message is received. In the second step  104 , an attempt is made to identify the voice mail message by telephone number identification. The telephone number identification is either ANI (Automatic Number Identification) or ICLID (InComing Line IDentification). In the third step  106 , the voice mail message is identified by the preferred speaker identification if the second step  104  is unsuccessful. The preferred voice mail identification  100  includes the telephone number identification in order to reduce processing time used for the preferred speaker identification method. 
     The preferred speaker identification method of the present invention is illustrated in FIG.  4 . The preferred speaker identification method  108  includes fourth, fifth, sixth, seventh, and eighth steps,  110 ,  112 ,  114 ,  116 , and  118 . In the fourth step  110 , voice characteristics of a telephone caller are compared to speaker templates. The speaker templates are representation of existing voice samples. In the fifth step  112 , a closest speaker template is determined. In the sixth step  114 , a matching coefficient is calculated. The matching coefficient is a measure of differences between the voice characteristics of the telephone caller and the closest speaker template. In the seventh step  116 , the voice mail message is marked with a name indicator associated with the closest speaker template if the matching coefficient is within an allowed range. In the eighth step  118 , the voice mail message is marked with an unknown indicator if the matching coefficient is outside the allowed range. Preferably, the unknown indicator is a word that indicates “unknown.” Alternatively, the unknown indicator is a blank. 
     Preferably, the speaker templates are VQ (Vector Quantization) codebooks, which are each formed by a small number of highly representative feature vectors. The feature vectors are preferably linear predictive coding cepstral coefficients. In order to compare the voice mail message to the VQ codebooks, the voice mail message is converted to voice mail message feature vectors, which are the linear predictive coding cepstral coefficients. Alternatively, the feature vectors are the linear predictive coding cepstral coefficients and first-order regression coefficients. The first-order regression coefficients are also known as delta values. 
     VQ (Vector Quantization), in general, is a digital compression technique. Preferably, the voice mail message is stored in a digital format. Alternatively, the voice mail message is stored in an analog format. If the voice mail message is stored in the digital format, the voice mail message is preferably not compressed. Alternatively, the voice mail message in the digital format is compressed using the VQ. 
     The matching coefficient is an average distortion, which is an average distance in phase space between the voice mail feature vectors and closest feature vectors of a closest VQ codebook. The allowed range is determined by a threshold distortion. If the average distortion is less than or equal to the threshold distortion, the matching coefficient is within the allowed range. If the average distortion is greater that the threshold distortion, the matching coefficient is outside the allowed range. 
     The preferred voice mail apparatus of the present invention is illustrated in FIG.  5 . The preferred voice mail apparatus  120  includes a user interface  122 , a processing unit  124 , and a storage media  126 . The user interface  122  is coupled to the processing unit  124 . The processing unit  124  is coupled to the storage media  126 . The user interface  122  is selected from a user interface group including an internal telephone, an external telephone, and a computer terminal. The processing unit  124  is selected from a processing unit group including a computer processing unit, first electrical circuitry associated with a specific voice mail system, and second electrical circuitry associated with a personal answering machine. The storage media  126  is selected from a storage media group including a magnetic storage media, an optical storage media, and a magneto-optical storage media. 
     In operation, a telephone caller leaves the voice mail message on the preferred voice mail apparatus  120  via the user interface  122 . The processing unit  124  performs the preferred voice mail identification method  100  and the preferred speaker identification method  108 . The processing unit  124  stores the voice mail message on the storage media  126 . A voice mail recipient retrieves the voice mail message via the user interface  122 . Preferably, the user interface  122  for voice mail recipient is the computer terminal used in conjunction with the internal telephone. Alternatively, the user interface is the internal telephone, used alone, or the external telephone. It will be readily apparent to one skilled in the art that the present invention can be implemented with computer software and an individual computer, including a speaker and microphone, with the individual computer coupled to a telephone system. 
     The voice mail recipient preferably uses the computer terminal in conjunction with the internal telephone and a voice mail GUI (Graphical User Interface) for the user interface  122 . 
     The voice mail GUI of the present invention is illustrated in FIG.  6 . The voice mail GUI  130  includes a title bar  48 , a drop-down menu bar  50 , an icon menu bar  52 , a system control bar  54 , a folder list  56 , a preferred voice mail message list  132 , and a message list status  60 . 
     The preferred voice mail message list  132  of the present invention will identify the name indicator determined by the preferred voice mail identification method  100  (FIG. 3) and the preferred speaker identification  108  (FIG.  4 ). In the preferred message list  132 , a first voice mail message  134 , with the name indicator of “McDermott, Gerald,” has been identified using the preferred speaker identification method  108 . A second voice mail message  136 , with the name indicator of “Smith, Sharon,” has been identified using the number identification. A third voice mail message  138 , with the unknown indicator, has been found to not have number identification and has been found to have the matching coefficient associated for the third voice mail message  138  to be outside the allowed range. 
     A fourth voice mail message  140 , with the name indicator of “Leblanc, Kelly,” has been identified using the preferred speaker identification method  108 . A fifth voice mail message  142 , with the name indicator of “Tucker, Daniel,” has been identified using the number identification. A sixth voice mail message  144 , having the name indicator of “408 555 7000,” has been identified using the number identification. 
     The preferred speaker template generation method of the present invention is ninth, tenth, eleventh, and twelfth steps,  152 ,  154 ,  156 , and  158 . In the ninth step  152 , an unidentified voice mail message is selected. In the tenth step  154 , a specific name indicator that is to be associated with the unidentified voice mail message is preferably input. Alternatively, a generic name indicator, such as a letter A, B, C, etc. is generated automatically. In the eleventh step  156 , a speaker template is created for the specific name indicator using the unidentified voice mail message. In the twelfth step  158 , the speaker template is preferably updated as additional voice mail messages are received and attributed to the specific name indicator using the additional voice mail messages. The unidentified voice mail message and the additional voice mail messages are training data for the speaker template. Alternatively, the twelfth step  158  is not performed. 
     An alternative voice mail identification method of the present invention is illustrated in FIG.  8 . The alternative voice mail identification method  160  includes thirteenth, fourteenth, and fifteenth steps,  162 ,  164 , and  166 . In the thirteenth step  162 , the voice mail message is received. In the fourteenth step  164 , the voice mail message is identified by the preferred speaker identification  108  (FIG. 4 ). In the fifteenth step  166 , the name indicator for the voice mail message is compared to the telephone identification if the telephone identification exists. If the telephone identification indicates a different name indicator than the name indicator, the voice mail message is also identified with the different name indicator. 
     An alternative speaker identification method of the present invention is illustrated in FIG.  9 . The alternative speaker identification method  170  includes sixteenth, seventeenth, eighteenth, nineteenth, twentieth, and twenty-first steps,  172 ,  174 ,  176 ,  178 , and  180 . In the sixteenth step  172 , the voice characteristics are compared to the speaker templates. In the seventeenth step  174 , the closest speaker template is determined. In the eighteenth step  176 , the matching coefficient is calculated. In the nineteenth step  178 , the voice mail message is marked with the name indicator associated with the closest speaker template provided that the matching coefficient is within the allowed range. In the twentieth step  180 , the voice mail message is marked with a questionable indicator if the matching coefficient is within a transition range that borders the allowed range. In the twenty-first step  182 , the voice mail message is marked with the unknown indicator if the matching coefficient is outside the allowed and transition ranges. 
     An alternative voice mail GUI of the present invention is illustrated in FIG.  10 . The first alternative voice mail GUI  190  incorporates the alternative voice mail identification method  160  and the alternative speaker identification method  170 . The alternative voice mail GUI  190  is identical to the voice mail GUI  130  of FIG. 6 with the exception that the preferred message list  132  of the voice mail GUI  130  has been replaced with an alternative message list  192  in the alternative voice mail GUI  190 . 
     In the alternative message list  192 , a seventh voice mail message  194 , with the name indicator of “McDermott, Gerald,” has been identified using the alternative speaker identification method  170 . An eighth voice mail message  196 , with the name indicator of “Smith, Sharon,” has been identified using the alternative speaker identification method  170 , which confirmed the name indicator using the number identification. A ninth voice mail message  198  is identified with the questionable indicator and is also identified with a possible caller named “Walters, Lisa,” since the matching coefficient is within the transition range. 
     A tenth voice mail message  200 , with the name indicator of “Leblanc, Kelly,” has been identified using the alternative speaker identification method  170 . An eleventh voice mail message  202 , with the name indicator of “Smith, Sharon,” has been identified using the alternative speaker identification method  170 . The eleventh voice mail message  202  has also been identified as having been placed from the telephone of “Tucker, Daniel,” using the number identification. A twelfth voice mail message  204 , with the name indicator of “Green, James,” has been identified by the alternative speaker identification method  170 . The twelfth voice mail message  204  has also been identified as having been placed from “408 555 7000” using the number identification. 
     The preferred speaker identification method  108 , in general, will correctly identify a particular message as being from a particular caller provided that a particular caller&#39;s speaker template is present. However, first, second, or third error scenarios could occur, especially if the training data is limited. 
     In the first error scenario, the particular caller&#39;s speaker template is present and the preferred speaker identification method  108  fails to identify the particular message as being from the particular caller so that a particular identification becomes a false negative identification. In the second error scenario, the particular caller&#39;s speaker template is not present and the preferred speaker identification method  108  misidentifies the particular message so that the particular identification becomes a false positive identification. In the third error scenario, the particular caller&#39;s speaker template is present and the preferred speaker identification method  108  both fails to identify the particular message as being from the particular caller and misidentifies the particular message so that the particular identification is both the false negative identification and the false positive identification. 
     A name indicator correction method of the present invention, for the first, second, and third error scenarios, is illustrated in FIG.  11 . The name indicator correction method  210  includes twenty-second, twenty-third, twenty-fourth, and twenty-fifth steps,  212 ,  214 ,  216 , and  218 . In the twenty-second step  212 , the particular message is selected for the name indicator correction method  210 . Next, the twenty-third step  214  is selected if the particular identification is the false negative identification only. The twenty-third step  214  updates the speaker template for the particular caller so that a future message from the particular caller will be identified. Alternatively, the twenty-fourth step  216  is selected if the particular identification is the false positive identification only. The twenty-fourth step  216  updates a false positive speaker template so that the future message from the particular caller will not be associated with the false positive speaker template. Further alternatively, the twenty-fifth step  218  is selected if the particular identification is both the false negative identification and the false positive identification. The twenty-fifth step  218  updates the speaker template for the particular caller and updates the false positive speaker template so that the future message from the particular caller will be identified correctly. 
     Testing was performed using the preferred speaker template generation method  150  (FIG. 7) and the preferred speaker identification method  108  (FIG.  4 ). Test data included twenty four sentences spoken by one hundred different speakers. The twenty four sentences for each of the one hundred different speakers were about two minutes in duration. Twelve of the twenty four sentences for each of the one hundred different speakers were used to generate the VQ codebooks using the preferred speaker template generation method  150 . Remaining twelve of the twenty four sentences for each speaker were used as sample voice mail messages. 
     The voice characteristics for each of the sample voice mail messages were compared to the VQ codebooks using the preferred speaker identification method  108 . A tuning parameter for the threshold distortion, referred to as delta, was used to adjust a success and a false acceptance. The delta, the success, and the false acceptance for the testing are listed in Table 1. Note that the voice characteristics were compared to all of the VQ codebooks and no attempt was made to distinguish between multiple matches of the voice characteristics of a single sample voice mail message with the VQ codebooks. So the test data indicate an increasing success and an increasing false acceptance with a larger delta or a larger threshold parameter, which is to be expected. 
     
       
         
               
               
               
             
           
               
                 TABLE 1 
               
               
                   
               
               
                   
                   
                 False 
               
               
                 Delta 
                 Success 
                 Acceptance 
               
               
                   
               
             
             
               
                 0.07 
                   72% 
                    0% 
               
               
                 0.08 
                 93 
                 1 
               
               
                 0.09 
                 98 
                 5 
               
               
                 0.10 
                 98 
                 11  
               
               
                   
               
             
          
         
       
     
     It will be readily apparent to one skilled in the art that other various modifications may be made to the preferred embodiment without departing from the spirit and scope of the invention as defined by the appended claims.