Facsimile equipment with voice signal identifying function

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Industrial application field]

The present invention relates to a facsimile machine having a voice signal identification function, and more particularly to a facsimile machine having a function of discriminating between a control signal and a voice signal of the facsimile machine.

【0002】

[Conventional technology]

With the widespread use of facsimile machines in ordinary households, a method of sharing a line between a telephone device and a facsimile machine has become common, and the facsimile machine and the telephone are automatically switched according to the other device. For example, in the line switching device described in Japanese Patent Application Laid-Open No. 63-87068, a response detection circuit for detecting the type of transmission signal returned from the other party is provided, and the response detection circuit communicates with the other party. A method of diagnosing which of the communication devices connected to the line is desired and connecting one communication device to the communication line according to the response from the other party has been proposed.

【0003】

[Problems to be Solved by the Invention]

In the above gazette, in response to the voice guidance "If you want to make a call, please say" Hello "", the voice response "Hello" is detected and the line is switched. Although it is described, the specific detection means is not described.

【0004】

When the voice response corresponding to the voice guidance is detected and the line is switched in this way, for example, a circuit for confirming that the voice signal is a voice signal by recognizing the content of the voice signal is used as the response detection circuit. However, in this case, there are various problems in feasibility, such as the scale of the means for detecting the voice response becomes very large and the time required for processing also becomes large.

【0005】

In addition, distinguishing the various control signals used in the facsimile machine from the voice signal is not only for switching the line described above, but also for performing various controls in the facsimile machine according to the response status from the other party. is necessary.

【0006】

An object of the present invention is to reliably identify various control signals and audio signals used in a facsimile machine in a short time with a simple configuration in order to improve the above-mentioned drawbacks in the prior art.

【0007】

[Means for solving problems]

In order to solve the above problems, the facsimile device having the voice signal identification function of the present invention is a signal identification unit that discriminates between the control signal and the voice signal of the facsimile device based on the difference in the distribution state of the spectrum of the signal from the other device. It has.

【0008】

The signal identification unit discriminates between the control signal of the facsimile device and the voice signal based on the difference in the peak frequency of the spectrum of the signal from the other device, and is based on the difference in the dispersion value of the spectrum of the signal from the other device. Anything that distinguishes between the control signal and the voice signal of the facsimile device can be used.

【0009】

[Action]

In a facsimile machine, when the other party to which the line is connected is a facsimile machine, the response signal becomes a control signal having a constant frequency, but when the other party is a human, the response signal has a wide frequency component. It becomes an audio signal to have. Therefore, by detecting the distribution state of the frequency spectrum of the response signal, it is possible to identify whether it is a control signal or an audio signal.

【0010】

[Example]

Hereinafter, the features of the present invention will be specifically described with reference to the drawings.

【0011】

FIG. 1 is a block diagram of a first embodiment of the present invention. In the first embodiment, the telephone line is switched between the ordinary telephone and the facsimile machine according to the identification result of the control signal or the voice signal.

【0012】

In the facsimile machine of the first embodiment, various instructions are input to the facsimile machine, and an operation display unit 1 for displaying the input information, an operating state of the facsimile machine, and the like, and an operation display unit 1 from the operation display unit 1. The control unit 2 that controls the operation of each part in the facsimile machine based on the instruction, the facsimile machine is connected to the telephone line 12, and the telephone line 12 is connected to the image information transmission system and the voice signal signal transmission system of the facsimile machine. A communication control unit 3 for switching control, a signal identification unit 4 for identifying whether the signal sent from the telephone line 12 is a control signal or an audio signal, a coding / decoding unit 5, and a scanner 6 for reading an image of a document. , A printer 7 that records and outputs images on paper, a display device 8 such as a cathode line tube display and a liquid crystal display that temporarily displays images, a storage unit 9, and an audio input / output unit 10 that functions as a telephone. , A voice guidance transmission unit 11 for supplying a guidance announcement or the like to the voice input / output unit 10 is provided. The coding / decoding unit 5 encodes the image signal obtained by scanning the image of the original with the scanner 6 and transmits it via the telephone line 12, and the code received via the telephone line 12. The data is decoded and supplied to the printer 7 or the display device 8.

【0013】

The control operation of automatic line switching in the above-mentioned facsimile machine will be described with reference to FIG.

【0014】

When the line is connected, the voice guidance sending unit 11 sends a message such as "Please tell me something if you want to make a call" to the other party according to the instruction of the control unit 2. The communication control unit 3 sends a response signal from the remote device to the signal identification unit 4. The signal identification unit 4 analyzes the signal from the communication control unit 3, identifies whether the signal from the remote device is the control signal of the facsimile device or the voice signal from the telephone, and controls the signal identification information. Send to Part 2. Details of the signal identification unit 4 will be described later.

【0015】

When the control unit 2 determines that the other device is a facsimile device, the control unit 2 sends a signal from the other device to the coding / decoding unit 5 via the communication control unit 3, decodes the signal, and uses the printer 7. Record output or display output to display device 8. Further, when the control unit 2 finds that the other device is a telephone from the signal identification information, the control unit 2 sends a signal from the other device to the voice input / output unit 10 via the communication control unit 3 and uses the telephone. Start communication.

【0016】

Next, the signal identification unit 4 will be described in detail, but prior to that, the signal sequence immediately after the line is connected will be described.

【0017】

A 1,100 Hz call signal (calling tone) is received from the calling terminal, or a 2,100 Hz called terminal identification signal is returned 1.8 to 2.5 seconds after the facsimile machine is connected to the telephone line.

【0018】

FIG. 2 is a diagram showing the distribution of the power spectra of the voice signal and the called terminal identification signal. The power spectrum of the called terminal identification signal is a single spectrum of 2100 Hz. On the other hand, in the case of an audio signal, the power spectrum is widely distributed, but the peak is about 1000 Hz.

【0019】

In the first embodiment shown below, the voice signal and the control signal are discriminated by detecting the difference in the peak frequency of the power spectrum between the voice signal and the called terminal identification signal.

【0020】

FIG. 3 is a block diagram showing a configuration example of one of the signal identification units 4 in the first embodiment.

【0021】

The signal identification unit 4 includes a low-pass filter unit 4a-1, a fast Fourier transform unit 4b-1, a spectrum peak detection unit 4c-1, and a signal determination unit 4d-1. The low-pass filter unit 4a-1 is a preprocessing unit for performing a fast Fourier transform, and band-limits the band in order to eliminate an error due to spectrum wrapping. The cutoff frequency of the low-pass filter unit 4a-1 is 3000 Hz. This is because it is only necessary to determine whether or not the voice signal and the called terminal identification signal have been received. Therefore, in order to detect the peak of the voice signal spectrum and the called terminal identification signal spectrum, the frequency range is the minimum necessary. is there. The fast Fourier transform unit 4b-1 calculates the power spectrum by the fast Fourier transform from the time series data filtered by the low-pass filter unit 4a-1. The spectrum peak detection unit 4c-1 detects the maximum spectrum value and frequency from the spectrum calculated by the fast Fourier transform unit 4b-1, and sends the signal to the signal determination unit 4d-1. When the maximum power spectrum value detected by the spectrum peak detection unit 4c-1 is equal to or greater than a preset threshold value, the signal determination unit 4d-1 has received an audio signal at the frequency at the maximum spectrum. It is determined whether or not, and the signal identification information which is the determination result is transmitted to the control unit 2. Further, when the maximum value of the power spectrum detected by the spectrum peak detection unit 4c-1 is smaller than the preset threshold value, it means that there is no response from the partner device. In this case, the partner device is a facsimile machine. It is determined that there is no signal identification information, which is the determination result, and is transmitted to the control unit 2.

【0022】

In the example shown in FIG. 3, the voice signal and the control signal are identified by detecting the difference in the peak frequency of the power spectrum between the voice signal and the called terminal identification signal, but in the other examples shown below, the voice is used. The audio signal and the control signal are distinguished by detecting the difference in the dispersion value of the power spectrum between the signal and the calling tone signal.

【0023】

FIG. 4 is a diagram showing the distribution of the power spectrum of the audio signal and the calling tone. The power spectrum of the calling tone is a single spectrum of 1100 Hz. On the other hand, in the case of an audio signal, the power spectrum is widely distributed, but the peak is about 1000 Hz. Since the peak frequency of the audio signal and the peak frequency of the calling tone are close to each other, it is difficult to distinguish between the two by the frequency difference at the maximum spectrum. Therefore, in the example described below, the audio signal and the control signal are distinguished by detecting the difference between the variance values of the two.

【0024】

FIG. 5 is a block diagram showing another configuration example of the signal identification unit 4.

【0025】

The signal identification unit 4 includes a low-pass filter unit 4a-2, a fast Fourier transform unit 4b-2, a spectral dispersion detection unit 4c-2, and a signal determination unit 4d-2.

【0026】

The low-pass filter unit 4a-2 is a preprocessing unit for performing a fast Fourier transform, and band-limits the band in order to eliminate an error due to spectrum wrapping. The cutoff frequency of the low-pass filter section 4a-2 is 2000 Hz. This is the minimum frequency range necessary for detecting the dispersion value of the audio signal spectrum and the calling tone spectrum because it is sufficient to determine whether or not the audio signal and the calling tone have been received. Since the cutoff frequency can be lowered as compared with the case where the called terminal identification signal is targeted, the amount of data can be reduced. The fast Fourier transform unit 4b-2 calculates the power spectrum by the fast Fourier transform from the time series data filtered by the low-pass filter unit 4a-2. The spectrum dispersion detection unit 4c-2 detects the maximum spectrum value and frequency from the spectrum calculated by the fast Fourier transform unit 4b-2, further calculates the dispersion value from each frequency component, and sends it to the signal determination unit 4d-2. To do. When the maximum power spectrum value detected by the spectral dispersion detection unit 4c-2 is equal to or greater than a preset threshold value, the signal determination unit 4d-2 uses the dispersion value calculated by the spectral dispersion detection unit 4c-2. It is determined whether or not an audio signal has been received, and the signal identification information which is the determination result is transmitted to the control unit 2. Further, when the maximum value of the power spectrum detected by the spectrum dispersion detection unit 4c-2 is smaller than the preset threshold value, it means that there is no response from the partner device. In this case, the partner device is a facsimile machine. It is determined that there is no signal identification information, which is the determination result, and is transmitted to the control unit 2.

【0027】

In the example shown in FIG. 5, the signal for determining the other device as a facsimile device is not limited to the calling tone of 1100 Hz, but may be applied to the called terminal identification signal of 2100 Hz and the control signal of other frequencies. it can. This is because the determination is made based on the variance value. Since the signal for determining the facsimile device has a single spectrum, the distribution is small and the dispersion value is small, and in the case of an audio signal, the dispersion value is widely distributed. This is because it utilizes the fact that it grows.

【0028】

In the first and second embodiments described above, the line is automatically switched based on the signal identification result, but the present invention is not limited to this, and other controls can be performed. ..

【0029】

Next, a second embodiment in which the signal identification unit of the present invention is applied to a facsimile machine having a retransmission function will be described.

【0030】

In a general facsimile machine, even if the other device is called, the other device is busy, or even if the other device is called and the line is connected, it cannot be transmitted normally and is interrupted in the middle. In some cases, it has a retransmission function for automatically calling the other device again.

【0031】

In a facsimile machine equipped with such a retransmission function, when a document is transmitted, if the telephone number of the other party is erroneously entered and a telephone call is made instead of the facsimile machine, the receiving side is the facsimile machine. Even if it is determined that the line is disconnected, the transmitting side automatically repeats the telephone call of the other party device by the retransmission function, which causes a problem that the receiving side is very annoyed.

【0032】

Therefore, in the second embodiment shown below, in the facsimile apparatus provided with the retransmission function, when a line is connected, the signal identification unit identifies whether the signal from the other apparatus is a facsimile control signal or an audio signal. , If it is an audio signal, the retransmission function is stopped.

【0033】

FIG. 6 is a block diagram showing a second embodiment in which the signal identification unit of the present invention is applied to a facsimile machine having a retransmission function. The members corresponding to the examples shown in FIG. 1 are designated by the same reference numerals.

【0034】

The facsimile apparatus shown in FIG. 6 includes an operation display unit 1, a control unit 2, a communication control unit 3 connected to a telephone line 12, a signal identification unit 4, a coding / decoding unit 5, a scanner 6, and the like. It includes a printer 7, a display device 8, and a storage unit 9. As shown in FIG. 7, the operation display unit 1 includes a numeric keypad 1a, a start key 1b, a display unit 1c such as a liquid crystal display, and the like.

【0035】

After setting the manuscript, dial the telephone number of the other device with the numeric keypad 1a, and start transmission with the start key 1b.

【0036】

The control unit 2 sends the telephone number of the other device to the communication control unit 3 in accordance with the instruction from the operation display unit 1. The communication control unit 3 calls the telephone number of the other device sent from the control unit 2. If the line cannot be connected because the other device is busy, the call is repeated by the retransmission function, and if the line cannot be connected even after calling a certain number of times, the call operation is stopped. When the line is connected, the signal from the other device is sent to the signal identification unit 4. The signal identification unit 4 analyzes the signal from the communication control unit 3, identifies whether the signal from the other device is a control signal of the facsimile device or a voice signal, and transmits the signal identification information to the control unit 2. Send out. As the signal identification unit 4, the one having the configuration shown in FIG. 3 or FIG. 5 described above is used.

【0037】

If a control signal of a certain frequency is detected from the other device after the line is connected, it is determined that the other device is a facsimile machine, and the control unit 2 is read by the scanner 6 and the coding / decoding unit 5 The image data encoded by is transmitted.

【0038】

Further, when the signal identification information indicates that the other device is a telephone, the control unit 2 stops the retransmission function and sends data indicating that the other device is a telephone to the operation display unit 1. As shown in FIG. 7, the operation display unit 1 displays the fact on the display unit 1c. Further, the control unit 2 sends and stores the telephone number of the other device determined not to be a facsimile device to the storage unit 9. The control unit 2 prohibits transmission when a matching number exists as compared with the telephone number stored in the storage unit 9 when the sender dials the telephone number of the other device using the numeric keypad 1a. Display that fact on the operation display unit 1.

【0039】

As described above, when the connected other party device is a telephone, the retransmission function is stopped, so that there is an effect that the receiver side does not repeat annoying mistaken telephone calls. In addition, it becomes clear to the sender that the transmission could not be performed because the other device was not a facsimile machine.

【0040】

[Effect of the invention]

As described above, according to the present invention, the control signal of the facsimile device and the audio signal are identified based on the difference in the distribution state of the spectrum of the signal from the other device, so that the configuration is simple and the time is short. Can distinguish between the two.

[Simple explanation of drawings]

[Figure 1]

It is a schematic block diagram which shows the structure of the 1st Example of the facsimile apparatus which has the audio signal identification function of this invention.

[Figure 2]

It is a figure which shows the distribution of the power spectrum of the voice signal and the called terminal identification signal for demonstrating the 1st signal identification method in this invention.

[Fig. 3]

It is a schematic block diagram which shows the structural example of the signal identification part based on the 1st signal identification method.

[Fig. 4]

It is a figure which shows the distribution of the power spectrum of an audio signal and a calling tone for demonstrating the 2nd signal identification method in this invention.

[Fig. 5]

It is a schematic block diagram which shows the structural example of the signal identification part based on the 2nd signal identification method.

[Fig. 6]

It is a schematic block diagram which shows the structure of the 2nd Example of the facsimile apparatus which has the audio signal identification function of this invention.

[Fig. 7]

It is explanatory drawing which shows typically the operation display part of the facsimile apparatus.

[Explanation of symbols]

1 Operation display unit, 2 Control unit, 3 Communication control unit, 4 Signal identification unit, 4a-1, 4a-2 Low-pass filter unit, 4b-1, 4b-2 Fast Fourier transform unit, 4c-1 Spectrum peak detection unit, 4c-2 Spectral dispersion detection unit, 4d-1, 4d-2 signal judgment unit, 5 coding / decoding unit, 6 scanner, 7 printer, 8 display device, 9 storage unit, 10 audio input / output unit, 11 voice guidance transmission Department, 12 telephone lines