Abstract:
This invention ( 10, 50 ) uses an interface ( 12, 52 ) to receive a voice input from a user, and a speech recognition unit ( 18, 54 ) coupled to the interface ( 12, 52 ) to monitor the voice input and recognize a predetermined set of voice commands from the voice input. The speech recognition unit ( 18, 54 ) generates a command signal that corresponds to the recognized voice command, which is received by a controller unit ( 20, 58 ). The controller unit ( 20, 58 ) activates a speech acquisition unit ( 16, 56 ) coupled to the controller unit ( 20, 58 ) to collect and stop collecting the voice input in response to a control signal generated by the controller unit ( 20, 58 ). a memory ( 24, 56 ) is provided to store the collected voice input.

Description:
This applications claims benefit to U.S. provisional application Ser. No. 60/032,507 filed Dec. 3, 1996. 
    
    
     TECHNICAL FIELD OF THE INVENTION 
     This invention is related in general to the field of personal electronic systems. More particularly, the invention is related to a hands-free audio memo system and method for making the same. 
     BACKGROUND OF THE INVENTION 
     It is common knowledge that we are currently living in the Information Age. Data come to us in visual, audio, and written forms through a myriad of channels: radio, telecommunications, television, internet, world wide web, and just plain seeing, hearing, and feeling things as events occur around us. There are many instances when it is desirable to retain some of the information in a more reliable manner than the ability or inability to recall data we are born with, for example, that telephone number announced on the radio, the location of that specialty store, or that ingenious idea about a novel gadget to solve a stubborn problem. 
     The old standby to record data is the pen and paper. However, there are times when it is inconvenient to write, such as when one is operating an automobile, or when pen and paper are not accessible. 
     Dictaphones, which use audio tape cassettes, and some newer digital recorders, have been used to fill this void. However, they all require the use of at least one hand to hold the device, and to operate the many buttons on the device to turn on the device, record, retrieve, erase, and turn off the device. Further, because it has been shown that the use of one hand to handle a wireless telephone while operating an automobile can lead to unsafe driving and possibly higher incidents of traffic accidents, it is less than desirable to also require the driver to devote the use of one hand to operate the recording device. 
     SUMMARY OF THE INVENTION 
     Accordingly, there is a need for an audio memo system and method therefor which enable hands-free operations. 
     In accordance with the present invention, a hands-free audio memo system and method are provided which eliminate or substantially reduce the disadvantages associated with prior devices. 
     In one aspect of the invention, an hands-free audio memo system and method uses an interface to receive a voice input from a user, and a speech recognition unit coupled to the interface to monitor the voice input and recognize a predetermined set of voice commands from the voice input. The speech recognition unit generates a command signal that corresponds to the recognized voice command, which is received by a controller unit. The controller unit activates a speech acquisition unit coupled to the controller unit to collect and stop collecting the voice input in response to a control signal generated by the controller unit. A memory is provided to store the collected voice input. 
     In another aspect of the invention, an hands-free personal memo system includes an analog interface receiving a voice input from a user, a speech recognition unit coupled to the interface adapted for receiving the voice input therefrom, recognize a predetermined set of voice commands from the voice input, and generating a command signal in response thereto. A controller unit is coupled to the speech recognition unit which generates a control signal in response to receiving the command signal from the speech recognition unit. A digital telephone answering device is coupled to the controller unit and analog interface for collecting and storing the voice input. 
     In yet another aspect of the invention, a method for hands-free audio memo includes the steps of receiving a voice input from a user, recognizing a voice commands in the voice input indicative of the user&#39;s desire to record an audio memo, collecting subsequent voice input, and storing the subsequent voice input. 
     Hands-free audio memo system and method therefor of the present invention provide a way for users to record audio memos and perform other functions without the use of a hand for its operation. This is especially advantageous for persons who are operating an automobile or performing other tasks that require concentration and generally the use of both hands. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     For a better understanding of the present invention, reference may be made to the accompanying drawings, in which: 
     FIG. 1 is a simplified functional block diagram of an exemplary hands-free audio memo system constructed according to the teachings of the present invention; 
     FIG. 2 is a simplified block diagram of an alternative embodiment of the hands-free audio memo system of the present invention; 
     FIG. 3 is an exemplary flowchart of a simplified hands-free audio memo algorithm according to the teachings of the present invention; 
     FIG. 4 is an exemplary flowchart of an hands-free audio memo algorithm according to the teachings of the present invention; 
     FIG. 5 is an exemplary flowchart of voice playback and memo management functions of the hands-free audio memo algorithm according to the teachings of the present invention; and 
     FIG. 6 is an exemplary flowchart showing exemplary voice inputs to the system according to the teachings of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The preferred embodiment(s) of the present invention is (are) illustrated in FIGS. 1-6, like reference numerals being used to refer to like and corresponding parts of the various drawings. 
     Referring to FIG. 1, a functional block diagram of an exemplary hands-free audio memo system  10  constructed according to the teachings of the present invention is shown. System  10  includes an analog interface  12  which receives voice input of a user captured by a microphone  14 , and converts the analog voice input into a digital voice input signal. Analog interface  12  is further coupled to a speech acquisition unit  16 , which functions to collect the digital voice input signal. The collected digital voice input signal is then provided to a speech recognition unit  18 , which receives the digital voice input signal and searches for a set of predetermined voice commands and responses stored in a speaker-independent speech model memory  19  and/or an optional speaker-dependent speech model memory  21 . For example, the voice command may be “MEMO START” or “TAKE MEMO” to initiate memo recording, “MEMO TERMINATE” to stop memo recording, and other appropriate responses. Further, certain commands and responses may be only valid during certain times and ignored at other times. For example, when memo recording is taking place, speech recognition unit  16  may only listen for a smaller set of commands and/or responses from the user, such as “MEMO TERMINATE,” and not “YES” or “NO.” 
     Speech recognition unit  18  is further coupled to a controller unit or microcontroller unit (MCU)  20 . When speech recognition unit  16  recognizes a valid command or response, it generates a signal to inform controller unit  20  to take appropriate actions. Controller unit  20  is further coupled to a speech compression unit  22 , which is also coupled to speech acquisition unit  16 . Speech compression unit  22  compresses the digital voice input signals collected by speech acquisition unit  16  using known compression algorithms and stores the compressed signals into a memory  24 . 
     A speech decompression unit  26  and a speech synthesis unit  27  are further coupled between controller unit  20  and analog interface  12 . Controller unit  20  instructs speech compression unit  26  to decompress stored speech in memory  28  and provide to speech synthesis unit  27  to produce a speech prompt or response at appropriate times, which is then broadcast to the user by a speaker  30  coupled to analog interface  12 . 
     Optionally, a communications link  31  may be provided to download voice input signals stored in memory  24  to a personal computer (not shown). In addition, a dialer  32  and link  34  may be further provided to a personal communications system (not shown) to perform functions related to telecommunications, such as dialing a particular number or “CALL HOME.” 
     FIG. 2 is a simplified block diagram of an embodiment of hands-free audio memo system  50  according to the teachings of the present invention. System  50  includes an analog interface  52  coupled to a speech recognition unit  54  and a digital telephone answering device (DTAD)  56 . DTAD  56  typically includes speech acquisition and compression functions, and a memory. a microcontroller unit  58  is further coupled to speech recognition unit  54  and DTAD  56 . 
     System  50  may be implemented with commercially available components or devices. For example, interface  52  may be implemented with TCM320AC36 or TCM320AC37 Voice-Band Audio Processors (VBAP)™ manufactured by Texas Instruments Incorporated of Dallas, Tex.; speech recognition unit  54  may be implemented with TMS320C5X Digital Signal Processor (DSP) also manufactured by Texas Instruments Incorporated; DTAD  56  may be implemented with the MSP58C8X product line of Texas Instruments Incorporated; and microcontroller unit  58  may be implemented with TMS370 family products of Texas Instruments Incorporated. 
     A single chip implementation is also contemplated by the present invention. For example, components in Texas Instrument&#39;s cDSP™ product line may be incorporated and formed on a single silicon substrate to construct an integrated circuit. For example, a C54X core for performing the speech recognition and DTAD functions, an Advanced RISC (reduced instruction set computing) Machines (ARM™) 7TDMI core for performing the controller unit functions, and a Voice-Band Audio Processor core for performing analog interface functions may be combined into a single integrated circuit. It may be seen that the above are merely examples and other suitable substitutes may be used. 
     Referring to FIG. 3 as well as the block diagrams in FIGS. 1 and 2, an exemplary process flow  70  for hands-free audio memo systems  10  and  50  is provided. Speech acquisition  16  or DTAD  56  and recognition  16  or  54  is first activated in step  72 . The activation may be done at the time the automobile (not shown) is started, by the push of a button, or by leaving the key in the accessory position, for example. In steps  72  and  74 , speech recognition unit  18  or  54  searches for a valid command appropriate for the occasion, such as “MEMO START” to start the memo recording process. Once a valid command is recognized, as determined in step  76 , controller unit  20  or  58  is notified, such as by a signal generated by speech recognition unit  18  or  54 , as shown in step  78 . Controller unit  20  or  58  then activates the memo function, as shown in step  80 . Once the system is ready, an optional audio prompt or speech (e.g., “MEMO SYSTEM READY”) may be generated in step  82  to signal to the user that he/she may begin to speak. A timer or counter (not shown) set for a predetermined time period may be started when speech acquisition  16  begins to capture voice input in step  84 . The collected voice input is converted to digital signals, compressed and stored in memory  24 , as shown in step  86 . When the timer expires, speech acquisition is stopped, as shown in step  88 . Controller unit  20  or  58  is then notified that memo recording terminated, as shown in step  90 , and execution returns to step  74  to be ready for the next memo. 
     A second version of the method for hands-free audio memo  100  is shown in FIG.  4 . Speech acquisition  16  or DTAD  56  and speech recognition  18  or  54  are activated either by starting the automobile, leaving the key in the accessory position, or the push of a button (not shown), for example, as shown in step  102 . Speech recognition  18  or  54  monitors the speech uttered by the user(s) in the vicinity and searches for recognizable valid voice commands and/or responses, such as a command to start the memo process, as shown in step  104 . 
     When it is determined that the captured voice input is a valid command, such as “MEMO START,” controller unit  20  or  58  is notified, as shown in steps  106  and  108 . Controller unit  20  or  58  in turn activates the memo function, as shown in step  110 . In step  112 , an audio prompt or speech (e.g., “MEMO SYSTEM READY”) may be generated to signal to the user that he/she may begin to speak. The user&#39;s speech is then captured and compared with recognizable commands appropriate for the circumstances, such as “MEMO TERMINATE” to end the process, as shown in steps  114  and  116 . Speech recognition  18  or  54  may be running in a low resource mode at this time to look for only those commands that are valid during this time, such as only the command to terminate or pause the memo taking process. If the captured utterance is not a recognizable and valid command, then it is collected, compressed, and stored, as shown in step  118 . If in step  116 , it is determined that the captured speech is a recognizable and valid command to end the memo process, for example, then controller unit  20  or  58  is notified, as shown in block  120 . Controller unit  20  or  58  then pauses speech acquisition, as shown in step  122 , and instructs speech decompression  26  and speech synthesis  27  to issue an audible prompt for confirmation, such as “READY TO TERMINATE MEMO?” The subsequent voice input is then captured and monitored for a valid response to the prompt, such as “YES” or “NO,” as shown in steps  126  and  128 . If the received voice input is not a recognizable valid response to the confirmation, then an appropriate audio response may be generated to reconfirm, as shown in step  132 . If the voice input is recognized as a response indicative that the user is not ready to terminate the memo process, then execution returns to step  112 , to continue to record memo. If on the other hand the voice input is recognized as an affirmative response in step  130 , then the memo function is stopped in step  134 , and controller unit  20  or  58  is notified in step  136 . Execution then returns to step  104  to prepare for the next memo. 
     FIG. 5 is a flowchart of memo playback and memo management functions of system  10  and  50 . At step  76  shown in FIG. 3 or step  106  shown in FIG. 4, if the voice input is not a valid start command, it is also checked for whether it is a valid playback command, as shown in step  140 . If it is, controller unit  58  is notified in step  142  and the user is prompted for additional input, which is captured, as shown in step  144 . The captured speech input is then examined to determined whether it is a valid response to the prompt given in step  144 , if not, some appropriate action is taken in step  148 , such as issue an appropriate audio statement. If it is a valid response, then the memo playback function  150  is launched, where the user may play back one or more previously recorded memos, skip one or more memos, etc. At the end of the memo playback function, the algorithm may return to step  74  in FIG. 3 or step  114  shown in FIG.  4 . 
     If in step  140  it is determined that the speech input is not a valid playback command, then a determination is made as to whether it is a valid memo management command in step  152 . If not, then the process may return to step  74  in FIG. 3 or step  114  shown in FIG. 4 to continue to capture the speech input. Otherwise, controller unit  58  is notified in step  154  and the user is prompted for additional input, which is captured, as shown in step  156 . The captured speech input is then examined to determined whether it is a valid response to the prompt given in step  158 , if not, some appropriate action is taken in step  148 , such as issue an audio statement. If it is a valid response, then the memo management function  160  is launched, where the user may perform operations such as delete, save, and protect on previously recorded memos. At the end of the memo management function, the algorithm may return to step  74  in FIG. 3 or step  114  shown in FIG.  4 . 
     Referring to FIG. 6, a more detailed process flow is shown. As voice input is captured in step  170 , it is determined whether it matched any recognizable and valid command and response in step  172 . For example, one or more recognized key phrases may be used to initiate system  50  in a memo recording mode  180 , memo playback mode  182 , memo management mode  184 , dialer mode  186 , and voice mail mode  188 , where each mode is shown with exemplary valid phrases recognized when system  50  is in the respective modes. The key phrases to launch each mode may include “MEMO START” to launch the memo recording functions; “MEMO PLAYBACK” to launch the memo playback functions; “MEMO MANAGEMENT” to launch the memo management functions; “CALL X” to launch the dialer functions; and “GET MAIL” to launch the voice mail functions. Thus, speech recognition unit  54  need only to focus on a subset of possible valid utterances as to speed up search and processing time and to conserve resources. 
     Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made therein without departing from the spirit and scope of the invention as defined by the appended claims.