JPH07154470A - Telephone-answering machine - Google Patents

Abstract

PURPOSE:To suppress the deterioration of an audio signal in sound quality without increasing the capacity of voice memory and to produce a counterattack tone against a prankster call without increasing the capacity of the voice mem ory in an a telephone-answering machine. CONSTITUTION:A control circuit 14 can change the bit rate of sound compression when an audio signal pattern is stored in the ROM 7 by selecting the same but rate as the one used in the sound compression of the audio signal pattern from memory 13 as the bit rate used when the audio bit pattern is read out and decoded, and furthermore, produce a prankster counterattack tone by selecting the bit rate different from the one used in the sound compression of the audio signal pattern from the memory 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention also relates to an answering machine having a memory in which a plurality of voice signal patterns such as response messages are stored as voice coded data by a waveform coding method.

[0002]

2. Description of the Related Art Conventionally, some answering machines store a plurality of voice signal patterns such as a ringing tone, a holding tone, and a response message in a voice memory and read them out as needed. When the pattern is stored in the voice memory, the voice signal is PCM (pulses).
It has been stored by compressing voice at a predetermined bit rate by a waveform coding method such as e code modulation). Then, when reading a voice signal pattern that is voice-compressed and stored at a predetermined bit rate by the waveform coding method, the voice signal pattern is decoded and voice-synthesized at the bit rate used when the voice signal pattern is stored,
A voice signal was cut off by a low-pass filter fixed in a predetermined frequency band and transmitted to a telephone line.

On the other hand, as a telephone having a mischievous repulsion function, as shown in, for example, Japanese Patent Laid-Open No. 4-335744, a repulsion button is provided on a keyboard and a telephone line is received based on the operation of the repulsion button. The voice signal is monitored for a predetermined time, and when the voice signal is received during the predetermined time, the voice signal is stored in the voice memory for a predetermined time and the stored voice signal is transmitted to the other party through the telephone line, Further, when no voice signal is received within a predetermined time, there is one that reads out a repulsion message stored in advance and sends it to the other party via a telephone line.

[0004]

However, when a plurality of voice signal patterns such as a ringing tone, a holding tone, and a response message are voice-compressed to a predetermined bit rate by a waveform coding method and stored in a voice memory, If the bit rate is reduced and stored, the capacity of the audio memory can be reduced, but the quantization noise when reading the stored audio signal pattern increases and the sound quality of the audio signal deteriorates. When stored, the quantization noise when reading out and playing back the stored voice pattern can be reduced, and the deterioration of the voice quality of the voice signal can be suppressed, but the capacity of the voice memory becomes large.

Further, in the telephone having the mischievous repulsion function as described above, a voice memory for storing a voice signal transmitted from the other party and a voice memory for storing a preset repulsion message are required. And
There is a problem that the memory capacity of the voice memory must be increased even if they are combined into one voice memory.

It is an object of the present invention to provide an answering machine which can suppress the deterioration of the sound quality of a voice signal without increasing the capacity of a voice memory and can repel a prank call.

[0007]

The present invention provides a ring tone,
A voice storage means in which a plurality of voice signal patterns such as a holding tone and a response message are stored as voice encoded data at a predetermined bit rate by a waveform encoding method, and a plurality of voice encodings stored in the voice storage means. A voice synthesizing unit that reads out data, decodes it at a predetermined bit rate and synthesizes it as a voice signal, a low-pass filter that cuts off the voice signal synthesized by the voice synthesizing unit in a predetermined frequency band, and a predetermined value by the low-pass filter. And a transmitting means for transmitting a predetermined voice signal cut off in the frequency band to the telephone line, and the predetermined voice coded data stored in the voice storing means in response to the incoming signal in the answering machine is voice synthesizing means. Read out as an audio signal, cut off in a specified frequency band with a low-pass filter, and then transmitted. In an answering machine for transmitting to the called party side by a step, a bit rate control for changing a bit rate used when the voice synthesizing means reads a plurality of voice coded data stored in the voice storing means and synthesizes them as a voice signal. Means are provided.

Further, there is provided cutoff frequency control means for changing the cutoff frequency of the low-pass filter based on the bit rate changed by the bit rate control means.

Further, when a plurality of voice signal patterns are stored in the voice storing means as voice coded data at a predetermined bit rate by the waveform coding method, the bit rate of the voice signal pattern transmitted to the telephone line by the transmitting means. , And the bit rates of other audio signal patterns are reduced and stored.

[0010]

Therefore, when the voice synthesizing means reads the voice signal pattern stored in the voice storing means as voice encoded data at a predetermined bit rate and synthesizes the voice, the bit rate used by the bit rate control means is changed. By doing so, the bit rate of the voice signal pattern stored in the voice storage means can be stored differently, and further, voice synthesis can be performed as a voice signal different from the voice signal stored in the voice storage means. It is possible to use this voice-synthesized voice signal as a mischievous repulsion sound.

Further, when the bit rate is changed by the bit rate control means, the cut-off control means changes the cut-off frequency of the low-pass filter so that the bit rate is lowered to read the stored audio signal pattern. Noise can be reduced.

Further, when a plurality of voice signal patterns are stored in the voice storage means, by increasing the bit rate of the voice signal pattern transmitted to the telephone line by the transmitting means and decreasing the bit rate of the other voice signal patterns,
It is possible to suppress the sound quality deterioration of the voice signal transmitted to the telephone line and reduce the voice storage capacity of the voice storage means.

[0013]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a schematic block diagram showing the configuration of an answering machine which is an embodiment of the present invention, and FIG. 2 is a flow chart showing the control operation of the answering machine.

In FIG. 1, reference numeral 1 is a telephone line for connecting to a telephone at the other end, 2 is a rectifying circuit for making the polarity of the direct current supplied from the telephone line 1 constant, 3 is the closing of the telephone line 1, and A hook switch circuit for opening 4 a call circuit for forming a call path with the other party's telephone, 5 a handset used for making a call with the other party's telephone, and 6 detecting an incoming signal coming from the telephone line 1. This is an incoming call detection circuit.

Reference numeral 7 is a ROM in which a plurality of voice signal patterns are compressed and stored at predetermined bit rates, and the bit rate of the voice signal pattern to be transmitted to the telephone line 1 when stored in the ROM 7 is increased. ,
For other voice signal patterns, voice compression is performed by lowering the bit rate. Reference numeral 8 is a voice synthesizing circuit for reading the voice signal pattern stored in the ROM 7, decoding the read voice signal pattern at a predetermined bit rate, and reproducing it as an analog voice signal, and 9 is a voice signal reproduced by the voice synthesizing circuit 8 in analog form. It is a low-pass filter that removes the quantization noise of.

Reference numeral 10 is a speaker amplifier for amplifying the received signal from the communication circuit 4 and the voice signal from the low-pass filter 9, and 11 is a speaker for outputting the voice signal amplified by the speaker amplifier 10 to the outside.

Reference numeral 12 denotes an operation input circuit provided with a ten-key pad for inputting a telephone number, an answering button for switching to an answering mode, and a repulsing button for generating a mischievous repulsing sound.
13 is a memory for storing the setting state of each function such as ringing tone and hold tone, and the bit rate of each voice signal pattern at the time of voice synthesis, and 14 is an incoming call detection signal from the incoming call detection circuit 6 and an operation input circuit 12. Operation signal and memory 1
3 is a control circuit that controls the hook switch circuit 3, the voice synthesizing circuit 8, and the low-pass filter 9 based on the data stored in 3.

The operation of the answering machine configured as above in the answering mode will be described.

In the absence mode by operating the answering button of the operation input circuit 12, when an incoming call signal from the other party's telephone arrives through the telephone line 1, the incoming call detection circuit 6 detects it and the incoming call detection signal is sent to the control circuit 14. Send to.
The control circuit 14 operates the memory 13 based on the incoming detection signal.
The address corresponding to the ringing tone stored in the ROM 7 is selected, and the bit rate used when the ringing tone is voice-compressed is selected from the memory 13. Then, the voice synthesizing circuit 8 reads the voice signal pattern corresponding to the address selected by the control circuit 14, and decodes the read voice signal pattern at the bit rate selected by the control circuit 14 to obtain a voice signal.

On the other hand, since the ringing tone is not a voice signal transmitted to the telephone line 1 but a voice signal emitted by the speaker 11, the bit rate of voice compression when it is stored in the ROM 7 is lowered. This voice signal pattern Quantization noise will increase if V is converted into a voice signal at the same bit rate. Therefore, when the audio signal pattern stored by reducing the audio compression bit rate is reproduced, the control circuit 14 controls the low-pass filter 9 to decrease the cutoff frequency to a predetermined value. Then, the audio signal that has passed through the low-pass filter whose cutoff frequency has been lowered is amplified by the speaker amplifier and then emitted to the outside by the speaker.

When the ringing tone sounds a predetermined number of times, the control circuit 14 controls the hook switch circuit 3 to close the telephone line 1 and to stop the ringing of the ringing tone from the speaker.

Then, the control circuit 14 selects an address corresponding to the response message stored in the ROM 7 from the memory 13 based on the connection of the telephone line 1 by the hook switch circuit 3, and when the response message is voice-compressed. The bit rate used is selected from the memory 13. Then, the voice synthesis circuit 8 reads the voice signal pattern corresponding to the address selected by the control circuit 14, and the read voice signal pattern is read by the control circuit 1.
The audio signal is decoded according to the bit rate selected in 4.

On the other hand, the response message is a voice signal transmitted to the telephone line 1, and since the sound quality is deteriorated in the telephone line 1, the bit rate of voice compression when stored in the ROM 7 is increased. Quantization noise at the time of decoding at the same bit rate to produce an audio signal is reduced. Therefore, when reproducing the stored audio signal pattern by increasing the audio compression bit rate in this way, the control circuit 14 controls the low-pass filter 9,
The cutoff frequency is set to a predetermined high value. And
The audio signal that has passed through the low-pass filter with a predetermined high cutoff frequency is amplified by the speaker amplifier,
The call circuit 4 is emitted to the outside by the speaker.
Is transmitted to the telephone line 1 via.

Then, a message message coming from the other party's telephone via the telephone line 1 is recorded on a magnetic tape or the like not shown, and when a tone signal comes from the telephone line 1, the control circuit 14 controls the hook switch circuit 3. Open telephone line 1.

That is, the control circuit 14 reads out the audio signal pattern stored in the ROM 7 and uses the same bit rate as the bit rate of the audio compression for storing the audio signal pattern read out from the memory 13 as the bit rate used for decoding. By selecting one, it is possible to change the bit rate of voice compression when storing it in the ROM 7, and therefore increase the bit rate for the voice signal pattern to be transmitted to the telephone line 1 and other voice signal patterns. , The memory capacity of the ROM 7 is minimized by storing at a reduced bit rate, and the audio signal to be transmitted to the telephone line 1 is quantized by a quantization noise in preparation for sound quality deterioration in the telephone line 1. It can be transmitted with less voice signal.

Next, a method of repelling a prank call will be described.

When the hook switch circuit 1 closes the telephone line 1 in response to an incoming call from the other party's telephone coming through the telephone line 1, the telephone call circuit 4 forms a telephone call path to establish a telephone call state. . In this call state, when the user determines that the call is a mischievous call based on the content of the call from the other party's telephone, when the repelling button of the operation input circuit 12 is operated, the control circuit 14 responds to a plurality of voice signal patterns stored in the ROM 7. An address is selected, and a bit rate different from the bit rate used when the voice signal pattern corresponding to the selected address is voice-compressed is selected from the memory 13. That is,
For example, when the voice signal pattern corresponding to the ringing tone is selected by selecting the address, the bit rate used for voice compression of the response message is selected from the memory 13.

Then, the voice synthesizing circuit 8 reads a voice signal pattern from the ROM 7 based on the address selected by the control circuit 14, and decodes the voice signal pattern at the selected bit rate to form a voice signal.

The voice signal synthesized by the voice synthesizing circuit 8 has its quantization noise removed by the low-pass filter 9 and is then input to the call circuit 4 and transmitted to the other party's telephone through the telephone line 1. .

At this time, the voice signal transmitted to the other party's telephone through the telephone line 1 becomes an unpleasant voice signal because it is decoded at a bit rate different from the voice-compressed bit rate when stored in the ROM 7. , It is a sound that is sufficiently effective as a sound to repel prank calls.

Next, the control operation in the absence mode as described above and the control operation in repelling the mischief will be described with reference to the flowchart of FIG.

In step F1, it is judged whether or not the answering machine is set to the answering machine by operating the answering button of the operation input circuit 12. If it is judged that the answering machine is in the answering machine, the process goes to step F2, and it is judged that the answering machine is not in the answering machine. In that case, the process proceeds to step F11. In step F2, it is judged whether an incoming signal comes from the telephone line 1 and the incoming call detection circuit 6
When the arrival of the incoming signal from the telephone line 1 is detected by the above, the process proceeds to step F3, and when the arrival signal of the incoming signal from the telephone line 1 is not detected by the incoming call detection circuit 6, the process proceeds to step F1 and the above operation is repeated. .

In step F3, it is judged whether the ringing tone is sounded a predetermined number of times (three times in this embodiment), and the speaker 1
When it is determined that the external sound has been sounded three times by 1, the process proceeds to step F4, and this operation is repeated until it is determined that the speaker 11 has externally sounded three times.

In step F4, the telephone line 1 is closed by the hook switch circuit 3 and the process proceeds to step F5. In step F5, the address corresponding to the response message and the bit rate when the response message is voice-compressed are selected. Then, the audio signal pattern is read from the ROM 7 based on the selected address, and the read audio signal pattern is decoded at the selected bit rate to form an audio signal. In step F6, the cutoff frequency of the low pass filter 7 is set based on the bit rate selected in step F5. Here, since the bit rate of the response message is increased, the cutoff frequency is set to a predetermined high value, and the process proceeds to step F7.

In step F7, the voice signal that has passed through the low-pass filter 7 is transmitted to the telephone line 1 via the communication circuit 4 and the speaker 11 emits sound.
Go to 8. In step F8, the message message is recorded based on the end of the transmission of the response message, and the telephone line 1
Based on the arrival of the tone signal from the hook switch circuit 3
Opens the telephone line 1 and moves to step F1.

On the other hand, when it is determined in step F1 that the mobile phone is not in the absence mode, and when the process proceeds to step F11, the ringing tone is given a predetermined number of times (20 times in this embodiment) in response to the incoming signal from the telephone line 1. ) Judging whether it was sounded,
If it is determined that the ringing tone has been sounded 20 times, step F4
If it is determined that the ringing tone is not sounded 20 times, the process proceeds to step F12. At this time, even when an incoming signal does not arrive from the telephone line 1, the process proceeds to step F12.

In step F12, the hook switch circuit 3
It is determined whether or not the telephone line 1 is closed. If it is determined that the telephone line 1 is not closed, the process proceeds to step F11. If it is determined that the telephone line 1 is closed, the process proceeds to step F13. In step F13, it is determined whether or not the telephone line 1 is opened by the hook switch circuit 3 in the communication state with the telephone of the other party due to the closing of the telephone line 1 in step F12. If it is determined that the telephone line 1 is not opened, the process proceeds to step F14. If it is determined that the opening has been completed, this flowchart is ended.

In step F14, it is determined whether or not the repulsion button of the operation input circuit 12 has been operated. If it is determined that the repulsion button has not been operated, the process proceeds to step F13. If it is determined that the repulsion button has been operated, step F15.
Move to.

In step F15, the address corresponding to the voice signal pattern stored in the ROM 7 is selected from the memory 13, and the process proceeds to step F16. In step F16, a bit rate different from the bit rate used for audio compression of the audio signal pattern corresponding to the address selected in step F15 is selected from the memory 13, and step F17
Move to.

In step F17, it is determined whether the bit rate value selected in step F16 is high. If it is determined that the bit rate value is not high, the process proceeds to step F18, in which the cutoff frequency of the low pass filter 9 is changed. It is lowered and the process proceeds to step F19. If it is determined that the bit rate is high, the process proceeds to step F19.

At step F19, the voice signal pattern corresponding to the address selected at step F15 is read from the ROM 7 and is decoded at the bit rate selected at step F16 to form a voice signal. In step F20, the quantization noise of the voice signal decoded in step F19 is removed by the low-pass filter 9, and the result is transmitted to the telephone line 1 and then this flowchart is ended.

[0043]

As described above, according to the present invention, voice compression is performed by changing the bit rate used when voice-compressing a voice-compressed and stored voice signal pattern according to the read voice signal pattern. The bit rate at this time can be made different for each audio signal pattern, and the memory capacity of the storage means can be effectively used. Furthermore, by making the bit rate used when voice-synthesizing the voice signal pattern different from the bit rate when voice-compressed, a repulsive sound for a prank call can be obtained.

Further, by changing the cutoff frequency of the low-pass filter for removing the quantization noise based on the bit rate used when synthesizing the speech-compressed speech signal pattern, the bit rate is reduced and the speech is compressed. It is possible to reduce the quantization noise that occurs when decoding the audio signal pattern.

The memory capacity of the storage means is increased by increasing the bit rate for voice signal patterns transmitted to the telephone line and decreasing the bit rate for other voice signal patterns to perform voice compression for storage. It can be suppressed to a minimum, and the voice signal to be transmitted to the telephone line can be transmitted as a voice signal with less quantization noise in preparation for syllable deterioration in the telephone line.

[Brief description of drawings]

FIG. 1 is a schematic block diagram showing the configuration of an answering machine that is an embodiment of the present invention.

FIG. 2 is a flowchart showing a control operation of the same answering machine.

[Explanation of symbols]

 1 Telephone line 2 Rectifier circuit 3 Hook switch circuit 4 Call circuit 5 Handset 6 Incoming detection circuit 7 ROM 8 Voice synthesis circuit 9 Low-pass filter 10 Speaker amplifier 11 Speaker 12 Operation input circuit 13 Memory 14 Control circuit

Claims (3)

[Claims] 1. A voice storage unit in which a plurality of voice signal patterns such as a ringing tone, a holding tone, and a response message are stored as voice encoded data at a predetermined bit rate by a waveform encoding method, and the voice storage unit. A voice synthesizing unit that reads out a plurality of stored voice encoded data, decodes them at a predetermined bit rate and synthesizes them as a voice signal, and a low-pass that cuts off the voice signal synthesized by the voice synthesizing unit in a predetermined frequency band. A filter and a transmitting means for transmitting a predetermined voice signal cut off in a predetermined frequency band by the low-pass filter to a telephone line, and in response to an incoming signal in an answering machine mode, a predetermined voice signal stored in the voice storing means. The speech coded data is read out by the speech synthesizing means to be an audio signal, and a predetermined frequency is set by a low pass filter. Used in an answering machine that transmits to the called party side by a transmitting means after being cut off in the range, when a plurality of voice coded data stored in the voice storing means by the voice synthesizing means is read and synthesized as a voice signal. An answering machine, which is provided with a bit rate control means for changing a bit rate. 2. The answering machine according to claim 1, further comprising cutoff frequency control means for changing the cutoff frequency of the low-pass filter based on the bit rate changed by the bit rate control means. 3. A bit rate of a voice signal pattern to be transmitted to a telephone line by the transmitting means when a plurality of voice signal patterns are stored in the voice storing means as voice encoded data by a waveform encoding method at a predetermined bit rate. The answering machine as set forth in claim 1, wherein the voice mail is stored at a higher rate and the bit rate of other voice patterns is reduced.