EP0660299B1 - Method and device for the transmission of dictations - Google Patents

Abstract

A method and a device for the transmission of dictations propose firstly to digitise the speech information of the dictation and to convert and to compress the digital information with the aid of a vocoder device. The conversion and compression can be carried out subsequent to the digitisation at a relatively low speed. Only after complete conversion and compression of the entire dictation is the latter then transmitted via a modem and a digital connection at high speed. On the receiver side, the storage and expansion takes place in the reversed sequence. As a result, telephone connection times can be shortened and the transmission costs can thus be reduced.

Description

Portable dictation machines are sometimes equipped with so-called acoustic couplers sold with which it is possible to have a pre-recorded Dictation to the mouthpiece of a telephone handset to couple. A dictation can then be made via the telephone line transferred to a recording device at the other end of the connection be where it's recorded. That way it is possible to transfer a dictation to an office while on the move, where it is then played and written by a playback device can be.

Playing during transmission over the telephone line happens at normal playback speed, as well recording on the receiving side.

It is also possible, of course, directly over the phone a dictation machine connected to the other party speak.

In both cases, depending on the underlying Fee structure of the postal authorities involved high costs surrender.

A data compressor system is already known (DE-31 29 155), in which the output signals of a Analog / digital converter immediately processed in real time and the processing results are stored digitally before they are broadcast. With this system must the processing of the digitized signals in real time take place, which means a corresponding effort.

Should the data compressor system for the transmission of data are used, the transmission also takes place in real time.

Also in another known method (US Pat. No. 4,841,299) the compression, coding and transmission takes place in real time.

An electronic mailbox system for telephone networks, that processes language information is in the AT&T font Technical Journal, Vol. 65, No. 5, September 1986, pages 23-33 disclosed. Here, digitization, compression and Transmission of voice information in real time carried out.

The invention has for its object a possibility create such dictations, i.e. Limited voice information Duration, at low cost, over the phone transfer to a place where the dictation is then written can be.

The first conceivable possibility of using the dictation machine on both Telephone connection ends at increased speed Letting it run will result in very little acceleration the transmission, as the frequency range changes the speed changes and phone connections only transmit a severely restricted frequency range. Therefore are at most increases in speed according to this method possible with a factor of 1.5.

The invention proposes instead to solve the above Task a method with the features of claim 1 and a device with the features of claim 11 and the Features of claim 12. Developments of the invention are the subject of the respective subclaims.

According to the invention, the dictation is ready edited that information into one for transmission be brought into a more suitable form. Then after complete a quick signal transmission via conversion a telephone connection, with the recording on the other End can be done in reverse.

Vocoder methods for voice transmission are known. In contrast to the present invention, their aim is however not, voice signals accelerate over a communication link to transmit, but instead, with a the lowest possible bit rate. The Speech can be converted immediately since the phone call is online to be led. Therefore, the well-known vocoder must be used work at high speed, which increases requirements the methods used and the hardware used.

In the method according to the invention, however, methods and compression devices are used which work slowly. The time that the compression process takes doesn't matter. Only the result is decisive of the compression process because the compressed Only transfer data after the compression has been carried out become.

With this method, a higher compression can be achieved the required transmission time than with faster playback.

It is particularly favorable if the invention is further developed it can be provided that a digital network for transmission is used, for example the one under construction ISDN.

The invention proposes converting the analog signals in digital data and its storage in real time perform.

According to the invention it can be provided that during speech pauses the digitization and / or the storage of the digitized Signals is interrupted. This leads to longer Language breaks can be shortened, for example to one Second, so that those that occur frequently when dictating Speech breaks do not lead to an extension of the transmission duration to lead.

According to the invention, the method can be applied to the Output signals of a dictation machine in playback mode to apply. Then the procedure in conventional Dictation machines can be used. According to the invention be provided, the dictation machine with an increased playback speed operate that to the limit of intelligibility is increased.

However, it is also possible to open the procedure directly Apply voice signals, for example to the output signals a microphone.

To receive the transmitted signals, according to the invention the features of claim 6 may be provided.

Even when transferring, the decompression after the The vocoder principle is slower than the transmission. It it is possible to decompress it already during the Let reception begin. Of course it is too possible to decompress or expand only after Let the transfer begin.

It can be provided that the reverse conversion of the expanded Signals into the analog voice signals in real time he follows. In particular, the speech signals can then be recorded on a conventional dictation machine from which then writing to tape can be done.

The device proposed by the invention with the Features of claim 10 is used for transmission while the Receiving device with the features of claim 11 the data transmitted according to the procedure. In particular it is of course possible and is proposed by the invention to use a single device for both processes. The digital memory and the modem can in this case work in both directions, i.e. both for receiving as also for sending the compressed data.

In particular, it can be provided that the entrance to the Device for connecting a dictation machine is formed.

It is also possible that the input goes directly to the connection a microphone can be formed, optionally also both options can be present at the same time. At the direct connection of a microphone can be provided that between the input and the analog / digital converter (A / D) a level control is provided which the voltage signals to a value suitable for the A / D converter.

In particular, it can be provided that the digital memory has a hard disk or is formed by a hard disk becomes. It is conceivable to cache the hard disk assign. Hard drives are currently available with large storage sizes and fast access time so that the Use of such a known element of the invention is preferred.

The invention proposes that the device be a processor on which the vocoder runs as a program. Since according to the invention the transfer and compression or decompression realized as staggered processes the program is not subject to a schedule Limitations so that in particular no special processors or particularly fast programs can be used have to.

In particular, can also be provided in the receiving device be that the expansion after completion of the transfer begins.

The invention proposes the device as an additional device to train for a computer, with only the im Computer not present, needed by the device Components are added, so that the digital memory of the computer and / or the processor of the computer and possibly including the modem built into the computer and its memory can be used.

In a further development, the invention proposes the device to assign a switchover device that causes the controller to the digitized uncompressed data via the D / A converter to create the playback device. It can here a very simple, purely software-implemented Act switching device. In this case it is possible the device also as a normal dictation machine use, i.e. with the possibility of direct playback.

According to the invention can be provided in a further development be that a switching device is provided which Vocoder causes the compressed stored signals after all the speech information has been compressed bypassing the modem as received data. It can then be done after compression and Expansion can be checked using the device like that Voice quality after compression and expansion is. This is particularly advantageous if the device has a possibility, the compression rate and thus the Change transmission speed.

According to the invention, provision can also be made for a device be that it offers the possibility of choosing whether a dictation at maximum speed or using multiple dictations reduced speed in one transmission process be transmitted.

Fig. 1

schematisch die Teile einer Vorrichtung zum Übertragen von Sprachinformation mit Hilfe eines erfindungsgemäßen Verfahrens;

Fig. 2

in gleicher Darstellung eine Vorrichtung zum Empfangen der übertragenen Sprachinformation;

Fig. 3

eine Vorrichtung, die zum Übertragen und Empfangen ausgebildet ist.

Further features, details and advantages emerge from the patent claims, the wording of which is made by reference to the content of the description, the following description of a preferred embodiment of the invention and with reference to the drawing. Here show:

Fig. 1

schematically the parts of a device for transmitting voice information using a method according to the invention;

Fig. 2

in the same representation, a device for receiving the transmitted speech information;

Fig. 3

a device which is designed for transmission and reception.

The device shown in Fig. 1 in overview an A / D converter 1, which is a known component acts. The A / D converter 1 converts at its input a line 2 incoming analog electrical signals in digital information to a line 3 to one Digital memory 4 are delivered. In the digital memory 4 the digital data are stored in a first area 5, in which the data is treated as a file.

The digital memory 4 contains a second area 6, which in the simplified diagram with the same size is, but does not have to be the same size.

Another data line 7 leads from the second area 6 to an output device 8, in which the data in a for the transfer be brought into a suitable form. The output device 8 stands over an output line 9 with a Modem 10 in connection. Modem 10 is on line 11 connected to a junction box for a telephone network. The actual dial-up connection to the telephone network can be made under program control respectively.

The device includes a controller 12 which is via control lines with the A / D converter 1, the output device 8 and connected to a device 13 for digital signal processing is. The device 13 for digital signal processing reads those contained in the first area 5 of the memory 4 digital data, it is converted using the vocoder method and stores the converted data in the second area 6 of the digital memory.

All of this is done under the control of the control device 12th

The device shown in Fig. 1 operates as follows. On the input line 2 is connected to a dictation machine 14, for example a standard dictation machine. In the A dictated device is inserted and played a discussed tape. Due to the finite length of the ribbon, the Voice information also limited. The dictation machine 14 is played at normal or increased playback speed and the initially available data will be analog converted into digital data in the A / D converter 1 in real time and in turn into the first memory area 5 saved. A speech pause occurs when the dictation is played on, the controller 12 interrupts the work of the A / D converter 1 until the speech pause has ended.

The memory area 5 is chosen so large that the one discussed Part of the dictation tape in digitized form in it fits in.

After complete digitization of the entire dictation, what the controller 12 determines, the compression now takes place of the data contained in the memory area 5 and their successive Storage in compressed form in the second memory area 6.

If necessary, you can start with the conversion right from the start the playback process can be started.

Once the entire dictation is in compressed form in the storage area 6 is included, the controller 12 now begins with the transmission using the modem 10. This runs in the usual way, which is therefore not explained in detail becomes. This voice transmission is now happening as fast as this is possible, the invention to achieve high Transmission speeds use the device preferred on an ISDN network.

Instead of creating a dictation machine 14, it could also be done directly a microphone can be connected.

The data transferred via the telephone connection arrive now on the receiving side into the device shown in FIG. 2, which a modem 10, an input device 15, a Digital memory 4, a digital / analog converter (D / A) 26 and a device 23 for digital signal processing and contains a control device 12. The device of the Fig. 2 is practically a mirror image of that of FIG. 1. Therefore, the individual functional units are not described again.

The operation of the device of Fig. 2 is as follows. After the connection has been established, the data to be transmitted Receive signals or data in the modem 10 and via the Input device 15 in a first area 16 of the digital memory 4 enrolled. This is how it is registered long how data is transferred. As soon as the last information the transfer is ended.

The contained in the first area 16 of the digital memory 4 compressed data get under control of the control unit 12 in the device for digital signal processing 13 and are there using the reverse vocoder method expands and in turn in a second area 17 of the Digital memory 4 written.

It can start processing right at the start of the transfer be started.

Only when the entire transmitted data expands and in Digital memory 4 are stored, so the expansion is completed digital data is converted back from the second area 17 of the digital memory 4 via the D / A converter 26, from which the restored one Voice information is output on a dictation machine 14. It changes depending on the degree of compression and expansion the quality of the language. The compression can do so be selected so that the dictation is still clearly understandable is.

Fig. 3 now shows the diagram of a device that the Transmission and reception summarized.

The device again contains a digital memory 4 which shown in two separate blocks for the sake of clarity but that can be realized as a unit can.

The device 13 for digital signal processing works with both blocks of the digital memory together. The mode of action the device is the same as in the figures 1 and 2. As can be seen, there is a single modem 10 that works as a send and receive modem. It can there is only one operation at a time, i.e. either sending as in the manner described in Fig. 1 or receiving as in the manner described in FIG. 2.

3 includes a level control 18, which is used in line 2 before the A / D converter 1 and enables the direct connection of a microphone 19. In the direct voice input using a microphone 19 is the 1 mentioned possibility to suppress speech pauses particularly important.

On the other hand, in the device of FIG. 3, the direct one Output via a speaker 20 possible, the left is indicated in Fig. 3.

The control device 12 of the device of FIG. 3, the individual control lines are not shown, still offers following possibility. It makes the facility possible 33 to control digital signal processing so that this after a dictation and its are fully compressed complete storage in the second area 6 of the digital memory 4 treats this area 6 as the area 16 and the compressed data contained there expands again and writes to memory area 17. Then they can go there contained expanded digital signals via the D / A converter 26 and the speaker 20 are output. It is so possible, not only the time required for the conversion measure, but also the quality of the voice information Check compression and expansion without the Information using the modem via the telephone connection is sent. Such a possibility of checking is in particular then of interest when using the device can set and change the compression level.

With the help of a switching device 21, the device makes it 3 also possible in real time in the first memory area 5 then stored dictation or also in every pause directly via the D / A converter 26 output the speaker 20. So can the device can be used as a digital dictation machine. Because the readout the memory area from the memory area 5 to the loudspeaker 20 5 does not delete, this can be done after the dictation are transmitted in the manner described.

If the device is designed as an additional part for a computer you only need level control, for example 18, the A / D converter 1 and the D / A converter 26 arrange a plug-in card and insert it into the computer. If necessary, a card with the Modem 10 can be used.

Claims (20)

1. Method for the transmission of speech of limited duration, particularly dictations, in which the speech signals are converted into analog electric signals, the analog electric signals are digitized, the digitized signals are compressed according to the vocoder principle, the compressed signals are stored and after the end of compression all the speech information to be transmitted is commenced with the transmission of the compressed signals over a telephone line, characterized in that the digitized, uncompressed signals are stored at least wordwise and that the compression takes place at a slower speed than the digitizing and storage of the uncompressed signals.
2. Method according to claim 1, wherein the method steps of conversion, digitizing and storing are performed in real time processing.
3. Method according to claim 1 or 2, wherein in the case of speech pauses digitization and/or storage of the digitized signals is interrupted.
4. Method according to one of the preceding claims, wherein the output signals of a playing back dictation machine are used as input signals for digitization.
5. Method according to according to one of the preceding claims, wherein the signals are transmitted over a digital network.
6. Method according to one of the preceding claims, wherein the received data are digitally stored at the receiver in the transmitted form, this is ended following complete transmission, the stored signals are expanded according to the vocoder principle, the expanded signals are digitally stored and the expanded signals are converted into analog electric signals.
7. Method according to claim 6, wherein expansion begins after the end of transmission.
8. Method according to claim 6 or 7, wherein the reconversion of the expanded signals takes place in real time processing.
9. Method according to one of the claims 6 to 8, wherein the analog electric signals are recorded on a dictation machine (14).
10. Apparatus for the transmission of speech of limited duration, particularly for performing the method according to one of the preceding claims, with an input for an analog speech signal, an A/D converter (1) connected to the input, a digital memory (4), a vocoder (13), which compresses the data and writs the compressed data in an area (6) of the digital memory (4), a modem (10), which is connected to the digital memory (4), and a control (12) which, following the complete storage of the compressed data of all the speech information to be transmitted, triggers the modem (10) for the transmission of said data from the memory area (6), characterized in that the digital memory (4) is connected to the output of the A/D converter (1), the vocoder (13) reads the uncompressed data from another area (5) of the digital memory (4), and that the vocoder operates at a slower speed than the A/D converter (1).
11. Apparatus for receiving transmitted speech of limited duration, particularly for performing the method according to one of the claims 1 to 9, with a modem (10), a digital memory (4), which is connected to the modem (10) and which stores the data received from the modem (10) in a first area (16), a vocoder (23), which is connected to the digital memory (4), reads data out of the first area (16) of the digital memory (4) and expands the data, as well as with a D/A converter (26), whose analog output is connected to a playback unit, characterized in that the vocoder (23) writes the expanded data in a second area (17) of the digital memory (4), the input of the D/A converter (26) is connected to the digital memory (4), and that the vocoder (23) operates at a slower speed than the A/D converter.
12. Apparatus according to claim 10 and claim 11, wherein the digital memory (4) and/or modem (10) operate in both directions.
13. Apparatus according to claim 10 or 12, wherein the input is constructed for the connection of a dictation machine (14) or a microphone (19).
14. Apparatus according to one of the claims 10 to 13, wherein the digital memory (4) has a hard disk.
15. Apparatus according to one of the claims 10 to 14, wherein the vocoder (13, 23, 33) is implemented as a program running on a processor.
16. Apparatus according to one of the claims 11 to 15, wherein expansion begins after the end of transmission.
17. Apparatus according to one of the claims 10 to 16, as an add-on unit for a computer, in which the digital memory (4) and/or the processor and/or the modem (10) of the computer are jointly used.
18. Apparatus according to one of the claims 11 to 17, with a switching device causing the control to apply the digitized, uncompressed data via the D/A converter (26) to the playback unit and/or which causes the vocoder (33) to treat the compressed, stored signals, following the end of the compression of all the speech information and whilst bypassing the modem (10), as received data.
19. Apparatus according to one of the claims 11 to 18, with a device for changing the compression rate and transmission duration.
20. Apparatus according to one of the claims 10 to 19, with a device for the, as desired, transmission of several dictations with a lower speed in a single transmission process.

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