Abstract:
This disclosure relates to a terminal unit for processing voice information which is adopted in a network system for transmitting and receiving voice information. This disclosure also pertains to a group of such terminal units. In a case where a voice converter is not provided in the terminal unit or when the use of the voice converter is suppressed, the terminal unit converts received voice information into a medium other than voice, for example, into characters, and thereby conveys it to a receiver. In a case where the terminal unit which receives the voice information is not provided with the function of converting the received voice information into a medium other than voice, the terminal unit requests another terminal unit within the terminal unit group to convert the voice information into a medium other than voice and thereby conveys it to a receiver.

Description:
This application is a continuation of application Ser. No. 07/654,003 filed Feb. 12, 1991 now abandoned. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a network system which is capable of transmission and reception of voice information using communication means. 
     2. Description of the Prior Art 
     In recent years, voice mail has been used at a practical level. In this voice mail, a message is input in voice using a computer systems, and the input voice information is sent to a local or remote computer through a network. At the local or remote computer, reproduction of the message is performed. 
     Voice mail is an excellent information transmission media because it has the excellent recordability possessed by document-oriented electric mail, that is, because it is capable of transmission of a message even when an addressee is absent, and because it has the high speed of the information transmitted in voice. 
     Transmission and reception of voice mail are performed in the manner described below: an audio message is input from a terminal unit provided with a voice input unit generally consisting of a microphone, an A/D converter, and a data compression unit, when necessary. The message is transmitted to the terminal unit which is an addressee in accordance with the transmission procedure of the network in the form of a file. At the terminal unit, which is the addressee, reverse conversion of the transmitted voice mail file is conducted in accordance with the communication protocol between the addressee and the addressor. Thereafter, a D/A converted message passes through an amplifier and then drives a speaker which makes the message audible to a receiver. 
     Transmission and reception of voice mail require special hardware. For transmission of voice mail, at least a microphone and an A/D converter are necessary. At the reception side, a D/A converter, an amplifier, a speaker and so on are necessary. The fact that the special hardware is required for transmission and reception of voice mail gives rise to a problem in that a transmitted message cannot be conveyed when the reception side of the voice mail does not have a voice reproducing hardware, and in that the cost of the hardware is quite high. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to provide a voice information-oriented network system with a conversion function for converting transmitted voice mail into a medium other than voice when audio reproduction of the voice information is impossible. 
     According to the present invention, the foregoing object is attained by providing a network system for transmitting and receiving voice information which is connected with a plurality of terminal units capable of converting the received voice information into a medium other than voice and of outputting the converted information. 
     Another object of the present invention is to provide a voice information-oriented network system which can obtain the information of a voice main in cooperation with another network terminal unit capable of converting the received voice mail into a medium other than voice when voice reproduction and conversion of the received voice mail into a medium other than voice are impossible. 
     In accordance with the present invention as described above, in a case when the terminal unit which receives the voice information is not provided with the conversion means for converting the voice information into information corresponding to an output medium other than voice, the voice information is transferred for conversion to another terminal unit provided with the conversion means, and the converted information is transferred back again to the terminal unit which receives the voice information. Consequently, even when the terminal unit, which receives the voice information, is not provided with the means for converting the voice information into information corresponding to an output medium other than voice, the information can be received in the medium other than voice. 
     Another object of the present invention is to provide a terminal unit for voice information provided with a conversion function for converting a transmitted voice mail into a medium other than voice when voice reproduction is impossible. 
     According to the present invention, the foregoing object is attained by providing a terminal unit connected to a network system for transmitting and receiving voice information. The terminal unit includes reception means for receiving information through the network system, identification means for identifying that the information received by the reception means is voice information, storage means for storing the voice information received by the reception means and identified by the identifying means, conversion means for converting the voice information into information corresponding to an output medium other than voice, and output means for outputting the information converted by the conversion means. 
     The invention is particularly advantageous because the terminal unit which receives the voice information can convert the voice information into information corresponding to a medium other than voice and output the results of the conversion so as to inform the user the received information even when the terminal unit is not provided with the audio reproduction means. 
     Furthermore, in a case when the voice information is received by the terminal unit capable of suppressing audio output of the voice information when the audio output is suppressed, since the voice information can be converted into an output medium other than voice, the user can be informed of the content of the received information in the form other than voice. Such a terminal unit is suitable for the site where audio output is a nuisance to other people or for the case when the information is confidential. 
     Furthermore, even when the voice information is received by the terminal unit which is not provided with the means for converting the voice information into information corresponding to an output medium other than voice, since the voice information can be converted into information corresponding to an output medium other than voice in cooperation with another terminal unit provided with the conversion means, it is not necessary for all the terminal units to be provided with the conversion means. This results in decreasing the production cost. 
     Furthermore, since conversion of the voice information is executed at the reception site, it is not necessary for the transmission site terminal unit to check whether or not the reception side terminal unit has audio output means when it transmits voice information thereto. 
     Other features and advantages of the present invention will be apparent from the following description taken in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the figures thereof. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention, and together with the description, serve to explain the principles of the invention. 
     FIG. 1 is a block diagram illustrating a voice mail processing terminal unit which is a typical embodiment of the present invention; 
     FIG. 2 is an example of a network environment to which the voice mail processing terminal unit is applied; 
     FIG. 3 is a flowchart showing the operation of the voice mail processing terminal unit; 
     FIG. 4 is an example of a converted voice message displayed on a screen; 
     FIG. 5 is a block diagram illustrating a group of processing terminal units according to another embodiment of the present invention; 
     FIG. 6 is a block diagram illustrating a client type voice mail processing terminal unit according to another embodiment of the present invention; and 
     FIG. 7 is a flowchart showing the process of the voice/character code conversion service in a server/client system according to another embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Preferred embodiments of the present invention will now be described in detail in accordance with the accompanying drawings. 
     FIG. 1 is a block diagram illustrating a voice mail processing terminal unit used in a network system according to a typical embodiment of the present invention. The terminal unit includes a voice mail operation controller 1 for controlling the operation of a voice mail system, a communication controller 2 for performing communications with other terminal units, a voice mail file 3 for storing voice mails, a man-machine interface 4 for connecting a user to the voice mail system, a voice converter checker 5, a voice/character code converter 6, a display controller 7, and a display unit 8. 
     FIG. 2 shows an example of a network environment to which the above-described voice mail processing terminal unit is applied. In FIG. 2, a reference numeral 200 denotes a computer system installed at a certain site, and a reference numeral 205 denotes a computer system installed at another site. In such a network environment, when voice mail is transmitted from, for example, a terminal unit 201 which belongs to the computer system 200 at a certain site to a terminal unit which belongs to the computer system 205 at another site, the voice information is transmitted on the following channel. That is, the voice mail input from the terminal unit 201 at the site 200 passes through a LAN (local area network) transmission path 203, a GW (gate way) 202 and then a WAN (wide area network) transmission path 204, and then reaches the site 205. At the site 205, the voice mail passes through a GW (gate way) 206 and a LAN (local area network) transmission path 208 and then reaches an addressee terminal unit 207. 
     In the above-described network environment, the mail system which employs the conventional network technique is required for transmission and reception of mail. The communication protocol of such a mail system is described in, for example, &#34;Handbook on Information Processing&#34; (In Japanese), published by OHMSHA Ltd., 1989, pp 761-766. The voice mail processing terminal unit shown in FIG. 1 is effective when voice mail has reached terminal unit 207 and when terminal unit 207 is not provided with a voice converter. 
     The operation of the voice mail system in this embodiment will now be described with reference to FIG. 3. 
     Here, it is assumed that voice mail operation controller 1 has already received through communication controller 2 a voice mail message which is sent from another terminal unit through a network (not shown), and that it has stored the message in voice mail file 3. 
     First, the user activates the voice mail processing terminal unit through the operation of man-machine interface 4 in step S301. Next, the user operates voice mail operation controller 1 in order to listen to the voice mail message, and voice mail operation controller 1 then thereby checks through voice converter checker 5 whether or not audio output of the voice mail message is available in the terminal unit in step S302. If it is identified in step S302 that the voice converter is enabled, the process proceeds to step S305 where voice converter checker 5 returns ready status of voice converter to the voice mail operation controller 1, and the voice file is output from the voice converter. If it is identified in step S302 that the voice converter is disabled, the process proceeds to step S303 where voice converter checker 5 returns not ready status of the voice converter to voice mail operation controller 1, and voice mail operation controller 1 commands the voice/character code converter 6 to convert the voice mail file into character codes. In step S303, voice/character code converter 6 converts the voice mail file read out from the voice mail file by voice mail operation controller 1 into character codes according to the prior art. 
     Finally, in step S304, voice mail operation controller 1 displays the converted character codes through display controller 7 on a display 8, such as a CRT display device, in the form of characters. At this time, it is preferable that the information is given in a manner such that the message displayed is the one converted from the voice mail into characters, as is shown in FIG. 4. In this way, a difference in the expression between the document and the voice mail is clarified, and mixture of the errors of the addressor with those of conversion can thus be avoided in a case when errors occur in the conversion of voice information into characters. 
     FIG. 4 shows a typical example of the converted information displayed on a CRT screen 400. A window 401 for displaying the voice mail in characters consists of a header display area 402 and a converted data display area 403. In header area 402, a message, for example,`Voice Mail Message (Converted)` is displayed as header to clearly indicate that the data displayed below is data converted from the voice mail into characters by the voice mail processing terminal unit. 
     It has been described in the operation of the above voice mail system, particularly, as to the process of step S302, that the voice converter checker 5 detects whether or not the voice converter is enabled. However, the present invention is not limited to the above. For example, an addition of means for suppressing audio output enables the operator to control the audio output, depending on his decision, even though the voice converter is provided in the terminal unit. Hence, the determination made in step S302 may not only be the detection of the presence or absence of the voice converter but also be the determination as to whether or not voice output is suppressed. 
     Furthermore it has been described in the above embodiment that the received voice mail is converted into characters and the converted characters are displayed on the CRT display. However, the received voice mail may also be output to output media other than the CRT display, such as a printer. 
     According to this embodiment, in a case where the voice converter is disabled, the user can receive the information carried by the voice mail and avoid confusion caused by the omission of the information, even though the user cannot enjoy the speedy information transmission which characterizes the voice mail. 
     [Another Embodiment] 
     In the above-described embodiment, the voice mail system of the terminal unit which receives a voice mail message (which is an addressee) is provided with a voice/character code converter. However, carrying out voice/character code conversion through the use of hardware requires us to equip each terminal unit with expensive hardware, and is hence uneconomical. 
     To cope with such a problem, a server/client model is employed in this embodiment. Each of the plurality of terminal units in the computer system sites, described in the aforementioned embodiment, constitutes a group having a plurality of terminal units. That is, one terminal unit in each terminal unit group functions as a server so as to centralize the process of converting the voice file into character codes, and other terminal units in the terminal unit group function as client units that display the results of the conversion, so as to decentralize the voice information processing. 
     FIG. 5 is a block diagram illustrating a terminal unit group to which server/client model is applied. In the configuration shown in FIG. 5, communications with the terminal units in other terminal unit groups are carried out through GW (gate way) 504, while communications with other terminals within that terminal unit group are made through transmission path 503 using a LAN, as in the case of the aforementioned embodiment. In such a server/client system, since client type terminal unit 502 is not provided with the function of converting the voice file into character codes, it requests server type terminal unit 501 through transmission path 503 to convert the voice file into character codes. 
     FIG. 6 is a block diagram illustrating terminal unit 502 used as a client in this embodiment. Client type terminal unit 502 used in this embodiment has the same configuration as that of the terminal unit shown in FIG. 1, with the exception that it has no voice/character code converter. Therefore, the same reference numerals are used to denote components which are the same as those shown in FIG. 1, description thereof being omitted. Also, terminal unit 501 used as a server has the same configuration as the terminal unit shown in FIG. 1, and description of the configuration is omitted. 
     The voice/character code conversion service is offered by the server type terminal unit 501 to client type terminal unit 502 through transmission path 503 in the manner described below with reference to FIG. 7. 
     First, the user requests the voice/character code conversion from voice mail operation controller 1 of client type terminal unit 502 to server type terminal unit 501 through communication controller 2 and transmission path 503 in step S701. Next, server type terminal unit 501 receives the request from client type terminal unit 502 in step S702, then activates voice/character code converter 6, and thereby executes the voice/character code conversion process in step S703. Subsequently, server type terminal unit 501 returns the results of the conversion to client type terminal unit 502 through transmission path 503 in step S704. In step S705, client type terminal unit 502 receives the results of the conversion through communication controller 2. Finally, in step S706, client type terminal unit 502 displays results such as those shown in FIG. 4 on display 8, using display controller 7. 
     In this embodiment, the server type terminal unit is of the type which carries out the process of converting the voice file into character codes. However, the server type terminal unit may also be of the type which carries out voice information conversion and displays the results of the conversion in characters. 
     The functions described in the above-described embodiments may be selectively carried out in terms of either hardware or software. For example, voice mail operation controller 1 and display controller 7, shown in FIG. 1, may be structured as a single software module. Also, voice converter checker 5 may be in the form of a switching variable using software. 
     As many apparently widely different embodiments of the present invention can be made without departing from the spirit and scope thereof, it is to be understood that the invention is not limited to the specific embodiments thereof except as defined in the appended claims.