JP2021076739A - Signal processing device, vibration device, signal processing system, program, and signal processing method - Google Patents

Abstract

To provide a signal processing device capable of reducing missing of a signal in a low-frequency range when performing signal processing.SOLUTION: A signal processing system includes a signal processing device having a signal processing section which performs processing so that a first signal as a signal included in a frequency band of a transmission object and a second signal as a signal having a frequency in a frequency band lower than the frequency band are included in the frequency band; and a signal processing device including an expansion section which performs processing so that a frequency band of an input signal is lowered below the frequency band, and an output section which outputs at least one of a signal corresponding to the frequency band from the processed signals and the signal having the band lower than the frequency band.SELECTED DRAWING: Figure 1

Description

The present invention relates to a signal processing device, a vibrating device, a signal processing system, a program, and a signal processing method.

As a signal processing technique for a time-series waveform signal, a technique for signal processing an audio signal is widely used. Generally, when signal processing an audio signal, the signal processing is performed not targeting the entire frequency band included in the audio signal, but targeting a specific frequency band. For example, by processing signals in the human audible band, it is possible to reduce the amount of information and remove noise. In this case, the signal in the low frequency band that is not included in the audible band is often intentionally cut and signal-processed. By outputting the signal in the audible band to the device in the subsequent stage, it is output as sound by, for example, a speaker or the like. It is possible to convey to the user a sound corresponding to a signal in the audible band.

Patent Document 1 discloses that in an existing speech processing system, the frequency of a signal is shifted to a low frequency band so that a high frequency signal in the audible band is not lost during signal processing. As a result, it is possible to transmit the high-frequency sound to the user by reducing the loss of the high-frequency signal in the audible band, and it is possible to suppress the deterioration of the sound quality.

Japanese Unexamined Patent Publication No. 55-33117

However, in the process of signal processing, since the frequency band of the target to be transmitted to the subsequent stage is limited, the signal of the frequency in the range of the transmission target can be transmitted to the latter stage, but the frequency outside the range of the transmission target is transmitted. The signal cannot be transmitted to the subsequent stage. For example, even if the signal in the audible band can be transmitted to the subsequent stage, the signal on the low frequency side of the audible band is not transmitted, so that the signal on the low frequency side cannot be used in the subsequent stage.
The technique of Patent Document 1 is limited to suppressing the loss of high frequency signals.

The present invention has been made in view of such circumstances, and an object of the present invention is a signal processing device, a vibrating device, and a signal processing capable of reducing a signal loss in a low frequency range when performing signal processing. The purpose is to provide systems, programs, and signal processing methods.

In order to solve the above-mentioned problems, one aspect of the signal processing device in the present invention is a first signal which is a signal included in the frequency band to be transmitted and a signal having a frequency on the lower frequency side than the frequency band. It has a signal processing unit that processes two signals so that they fit in the frequency band.

Further, one aspect of the signal processing device in the present invention is an extension portion that is processed so that the frequency band of the input signal is lowered to the low frequency side of the frequency band, and a signal corresponding to the frequency band among the processed signals. And an output unit that outputs at least one of the signals on the low frequency side of the frequency band.

Further, one aspect of the vibration device in the present invention includes the above-mentioned signal processing device and a vibration unit that generates vibration based on a signal obtained from the signal processing device on the lower frequency side than the frequency band.
Further, one aspect of the signal processing system in the present invention includes a signal processing device having the above-mentioned signal processing unit and the above-mentioned signal processing device having the extension unit.
Further, one aspect of the program in the present invention may be a program for operating a computer as any of the above-mentioned signal processing devices.
Further, in one aspect of the signal processing method in the present invention, the signal processing unit has a first signal which is a signal included in the frequency band to be transmitted and a second signal which is a signal having a frequency lower than the frequency band. Is a signal processing method that processes so as to fit in the frequency band.
Further, in one aspect of the signal processing method in the present invention, the extension section is processed so that the frequency band of the input signal is lowered to the low frequency side of the frequency band, and the output section is the frequency of the processed signal. This is a signal processing method that outputs either a signal corresponding to a band or a signal on the lower frequency side than the frequency band.

Further, in the present invention, when recording / reproducing or transmitting a signal waveform such as vibration, frequency conversion processing is performed on the signal input portion and frequency inverse conversion processing is performed on the output portion. It is possible to process a signal having a band component other than the target frequency band of the processing system without missing it.
In addition, processing for performing signal frequency conversion / inverse conversion processing is added to the input portion and output portion of the recording / transmission processing, respectively. In the frequency conversion process, the signal is converted by performing compression / decompression processing in the time space of the signal or shift processing in the frequency space. In time-space processing, the vibration waveform is compressed in the time direction for each very short section at the input part, and a regulation signal such as a sine wave or pulse code that can be detected by inverse conversion is inserted for the time that is no longer needed due to the compression. By doing so, the unnecessary part is detected and deleted at the time of inverse conversion, and the signal part is expanded.
In the processing in the frequency space, the waveform signal is converted into the frequency space by the Fourier transform in the input / output portion, and then the frequency shift processing is performed to perform the inverse Fourier transform.

As described above, according to the present invention, it is possible to reduce the loss of a low frequency signal when performing signal processing.

It is a schematic block diagram which shows the structure of the signal processing system 1 by one Embodiment of this invention. It is a schematic block diagram which shows the structure of the signal processing apparatus 10. It is a figure explaining the method of processing a signal by compression / decompression in time space. It is a figure explaining the method of solving the problem of signal discontinuity at both ends of a processing section. It is a figure explaining the frequency conversion process by shifting a signal in a frequency space. It is a schematic block diagram which shows the structure of the signal processing apparatus 50. It is a sequence diagram explaining the operation of the signal processing system 1 in FIG. It is a schematic functional block diagram which shows the structure of the signal processing apparatus 10A which is another embodiment of a signal processing apparatus 10. It is a schematic functional block diagram which shows the structure of the signal processing apparatus 50A which is another embodiment of the signal processing apparatus 50.

Hereinafter, the signal processing device according to the embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic block diagram showing a configuration of a signal processing system 1 according to an embodiment of the present invention.
The signal processing system 1 includes a signal processing device 10, a storage device 20, a wireless communication device 30, a wireless communication device 40, a signal processing device 50, and a drive device 60.
In the signal processing system 1, when recording, reproducing, and transmitting a signal to be processed, the signal processing device 10 performs frequency conversion processing on the waveform signal at the signal input portion and stores it in the storage device 20 or stores it in the storage device 20. By transmitting from the wireless communication device 30 to the wireless communication device 40, the waveform signal can be transmitted to the signal processing device 50. Then, in the output portion, the signal processing device 50 performs frequency inverse conversion processing, so that signals having band components other than the frequency band targeted by the processing system can be transmitted to the subsequent drive device 60 without being lost. ..

The signal handled here includes a signal in a frequency band defined as a target to be transmitted for the purpose of reducing the amount of information and removing noise when encoding or decoding the signal or when compressing or decompressing the signal. , Other signals are removed so that they are not included. By treating the signal as a signal in the frequency band in the frequency band defined in this way, the input waveform signal can be transmitted by using a transmission technique conforming to a generally used standard.
Here, in the present embodiment, attention is paid to utilizing a signal having a frequency on the low frequency side among the signals to be removed. Regarding the signal of the frequency on the low frequency side, the frequency may be included in the audible band, but the signal in the non-audible region is mainly utilized. When outputting a signal in such an inaudible region, for example, by inputting this signal to a vibration device, it is possible to output it as vibration. When it is output as vibration, it can be transmitted to the user as a vibration waveform (vibration signal) as perceived by the skin, for example. The vibration device is not driven on and off in a constant vibration mode, and can output vibrations of various frequencies according to the vibration waveform.

Here, as the recording / playback technology of the audio processing system, for example, a digital audio recording format using a computer according to a format such as wave, mp3, wmv, an analog audio recording format such as a magnetic tape, a record, or the like can be used. it can. The storage device 20 stores data corresponding to the waveform signal in a digital voice recording format. The storage device 20 is a storage medium, for example, an HDD (Hard Disk Drive), a flash memory, an EEPROM (Electrically Erasable Programmable Read Only Memory), a RAM (Random Access memory, Memory), or a RAM (Random Access memory) It is composed of any combination of storage media. As the storage device 20, for example, a non-volatile memory can be used.
Further, such data may be recorded on a recording medium such as a CD (Compact Disc) or a DVD (Digital Versatile Disc) instead of the storage device 20.

In addition, as audio processing system transmission technology, SBC (subband codec), AAC (Advanced Audio Coding), aptX (aptX), aptXHD (aptX HD), LDAC (Eldac), aptX in Bluetooth (registered trademark) Wireless digital communication via a codec such as Low Latency or analog communication using AM / FM waves can be used. Such a transmission technique can be used for communication between the wireless communication device 30 and the wireless communication device 40.

These recording / playback technologies and transmission technologies have been implemented in PCs (personal computers), smartphones, tablets, other video playback devices, radio receiving devices, etc., and are already widely used.

The processing of the input part and the output part may be performed by using software running on a computer capable of signal processing in real time, or by using a dedicated DSP (digital signal processor).

The drive device 60 is, for example, a device including a speaker and a vibration device, and is a sound signal from the speaker based on a signal in the frequency band to be transmitted (for example, a sound signal) based on a waveform signal obtained from the signal processing device 50. Sound and vibration can be output by outputting a signal or driving a vibration device based on a signal having a frequency lower than the frequency band to be transmitted (for example, a signal for vibrating). The vibrating device is composed of, for example, a motor and a vibrating unit, drives the motor based on the waveform signal obtained from the signal processing device 50, and converts the rotation of the output shaft of the motor into vibration by the vibrating unit. The vibration may be output. As a result, it is possible to transmit the vibration of the frequency on the low frequency side of the frequency band to be transmitted to the user.
Further, the drive device 60 does not have to have a speaker. In that case, the drive device 60 receives only the signal on the low frequency side of the frequency band to be transmitted from the signal processing device 50 to drive the vibration device. You may.

FIG. 2 is a schematic block diagram showing the configuration of the signal processing device 10.
The signal processing device 10 includes a signal input unit 110, a signal processing unit 120, and an output unit 130.
The signal input unit 110 inputs a signal. For example, the signal input unit 110 inputs sound data according to any of the formats such as wave, mp3, and wmv.

The signal processing unit 120 processes the first signal, which is a signal included in the frequency band to be transmitted, and the second signal, which is a signal having a frequency lower than the frequency band, so as to fit in the frequency band. For this processing, for example, any one of the following two can be used.
(1) The signal processing unit 120 processes the first signal and the second signal by compressing them in the time direction.
FIG. 3 is a diagram illustrating a method of processing a signal by compression / decompression in time and space. In FIG. 3, the graph indicated by reference numeral (a) shows the signal before processing by the signal processing unit 120, and the graph shown by reference numeral (b) shows the signal after processing by the signal processing unit 120. Shows a signal.
Here, the vibration waveform W1 is input as an input signal. The vibration waveform W1 is a continuous signal. The vibration waveform W1 is a signal including a first signal and a second signal.
With respect to the vibration waveform W1, the unit time of processing is set to the section S1 in the time direction, and the vibration waveform W1 included in this section S1 is compressed in the time direction so as to be the section S2 (where S1> S2).

As a result, the frequency of the vibration waveform W1 is compressed in the time direction including the first signal and the second signal, so that the frequencies of the first signal and the second signal become high frequencies according to the compression rate. Therefore, even the second signal having a low frequency that is not included in the frequency band to be transmitted becomes a high frequency according to the compression rate. For example, when the compression rate is doubled, the frequency is doubled. Therefore, by compressing the second signal in the time direction to such an extent that the frequency falls within the frequency band to be transmitted, the second signal can also be transmitted to the subsequent stage.
Here, the ratio between the section S1 and the section S2 can be expressed as the compression ratio R. The compression ratio R may be determined based on the frequency of the second signal and the frequency within the frequency band to be transmitted. Further, the unit time of the vibration waveform W1 after compression can be expressed as S2 = S1 × R. When the vibration waveform W1 is compressed in the time direction, a blank section D is generated between the section S1 and the section S2. This section D is a blank section with respect to the original signal length, and the length in the time direction can be obtained by the equation D = S1-S2.
Here, by setting the section S1 sufficiently small, the time required for compression and decompression can be shortened, so that the delay in transmission can be reduced and the real-time property is improved.

Here, the signal processing unit 120 has a signal length (section S1) which is the length of the signal to be compressed in the time direction and a signal length (section S1) which is the length of the signal after being compressed in the time direction in the time direction. The third signal (regulation signal W3), which is a signal having a signal length corresponding to the difference (section D) from S2), is filled at least one before and after the compressed signal (vibration waveform W2) in the time direction. You may try to do it.

In FIG. 3, a case where the regulation signal W3 is added to the rear stage side in the time direction of the vibration waveform W2 is illustrated. Here, since the start time of the signal of the vibration waveform W1 and the start time of the vibration waveform W2 are compressed to be the same, the regulation signal W3 is added to the subsequent stage of the vibration waveform W2.
Further, the regulation signal W3 may be added to the front stage side in the time direction of the vibration waveform W2. In this case, after adding the regulation signal W3 so that the start time of the signal of the vibration waveform W1 and the start time of the regulation signal W3 are the same, the vibration waveform W2 is arranged after the regulation signal W3. May be good. In this case, the end time of the vibration waveform W1 and the end time of the vibration waveform W2 are the same.

The regulation signal W3 is a signal regulated in advance, and a signal sufficiently distinguishable from the vibration waveform W1 and the vibration waveform W2 can be used. For example, the regulation signal W3 is a signal such as a sine wave or a pulse code. You may use it. Since the regulation signal W3 is predetermined, the regulation signal W3 can be easily detected on the subsequent stage side (for example, the signal processing device 50), the regulation signal W3 is removed, and the vibration waveform W2 is extracted. It becomes possible. When extracting the vibration waveform W2, the position of the section D on the time axis is detected by frequency analysis or pattern matching processing, the section S2 is derived, and the vibration waveform W2 is extended in the time direction so that the section S2 becomes the section S1. Perform processing (reverse conversion).

In this embodiment, the case where the regulation signal W3 is filled in the front stage or the rear stage of the vibration waveform W2 has been described, but the regulation signal W3 is divided into two as the regulation signal W3a and the regulation signal W3b, and the vibration waveform W2 The regulation signal W3a may be filled in the front stage, and W3b may be filled in the rear stage of the vibration waveform W2. Here, the sum of the sections of the regulation signal W3a and the regulation signal W3b in the time direction may be the same length as the section D.

The signal processing unit 120 performs such processing for the next section each time the time corresponding to the section S1 of the vibration waveform W1 arrives.
Further, the signal processing unit 120 may perform processing on the vibration waveform by either analog processing or digital processing. In the case of digital processing, when compressing in the time direction, the signal processing unit 120 may compress the signal by deleting samples at regular intervals, and the signal processing device 50 expands in the time direction. In that case, the sample may be expanded by interpolating by inserting the sample at regular time intervals. This simplifies the implementation.

FIG. 4 shows signals at both ends of the processing section when compression / decompression, coding / decoding, FFT, etc. are performed by referring to the front-back waveform of a certain section in the voice processing system used in the above method. Is a way to solve the problem of discontinuity.
Both ends of the processing section are a time before the start time of the processing section and a time after the end time of the processing section in the time direction.

In this case, the signal processing unit 102 adds spare sections C to the front and rear in the time direction of the processing section S1 to perform processing. In FIG. 4, as an example, the signal processing unit 120 adds a section C11 as a spare section C before the section S1 and a section C12 as a spare section C after the section S1. On the other hand, when the decompression unit 520 performs the inverse transformation, the decompression processing is performed by deleting the signals for C × R before and after the processing section S2. Here, R is the compression ratio of the waveform, which can be obtained by S2 / S1. After performing the inverse transformation, the extension unit 520 obtains the section C21 in front of the section S2 by C11 × R, and deletes the obtained section C21. Further, the extension unit 520 obtains the section C22 behind the section S2 by C12 × R, and deletes the obtained section C22.

By setting it to be larger than the front-back reference processing window size of the voice processing system that uses the spare section C, discontinuity at both ends of the processing section S1 can be suppressed.

(2) The signal processing unit 120 has a conversion unit 121, and when the input signal is processed by a method different from the compression in the time direction described in (1) above, the function of the conversion unit 121 is used. .. The conversion unit 121 converts the first signal and the second signal into a frequency space signal by Fourier transforming the first signal and the second signal. After the signal to be processed is converted into a signal in the frequency space by the conversion unit 121, the signal processing unit 120 shifts the frequency so that the converted frequency space signal falls within the wave number band of the transmission target.

FIG. 5 is a diagram illustrating a frequency conversion process by shifting the signal in the frequency space.
In FIG. 5, the graph shown by the reference numeral (a) shows the vibration waveform W5 after being converted by the conversion unit 121, and the graph shown by the reference numeral (b) shows the vibration waveform W5 after being processed by the signal processing unit 120. The vibration waveform W6 of is shown.

In the graph represented by the reference numeral (a) of FIG. 5, the vibration waveform W5 has a signal intensity from the frequency on the low frequency side to the high frequency side. The conversion unit 121 converts the vibration waveform W5 input from the signal input unit 110 into intensity component information for each frequency by performing a Fourier transform process such as FFT (Fast Fourier transform).
The signal processing unit 120 shifts the frequency of the vibration waveform W5 converted by the conversion unit 121 so that it falls within the frequency band for transmitting transmission on the low frequency side. In the graph represented by the reference numeral (b) in FIG. 5, the frequency increases in the positive direction (frequency increases) according to the frequency band (shift amount S) on the low frequency side from the frequency f1 to the frequency f2 (f1 <f2). The vibration waveform W5 is shifted as a whole. Upon shifting, the frequency is shifted without changing the signal strength of the vibration waveform W5.

The shift amount S may be shifted to the high frequency side in the frequency space to the extent that the frequency falls within the frequency band to be transmitted. For example, when the lower limit of the frequency band to be transmitted is 20 Hz, the shift amount S of the vibration waveform W5 is set to 20 Hz, so that the signal component of 20 Hz or less is processed so as to be contained in the frequency band to be transmitted. Can be done.
As a result, the frequency component on the low frequency side of the vibration waveform W5 can be contained in the frequency band to be transmitted, so that the second signal can also be transmitted to the subsequent stage.

Returning to FIG. 2, the output unit 130 outputs the signal processed by the signal processing unit 120. This output is, for example, an output to a storage device, an output to a wireless communication device, a writing to a recording medium, or the like. By outputting to the storage device, the signal output from the output unit 130 is written to the storage device. Further, by outputting to the wireless communication device, the signal output from the output unit 130 is wirelessly transmitted to an external device (other wireless communication device or the like) by the wireless communication device.

Next, FIG. 6 is a schematic block diagram showing the configuration of the signal processing device 50.
The signal processing device 50 includes a signal input unit 510, an extension unit 520, and an output unit 530.
The signal input unit 510 inputs a signal. The signal input unit 510 is sound data according to one of the formats such as wave, mp3, and wmv, and has the same format as the format input by the signal input unit 110 of the signal processing device 10. May be good.

The extension unit 520 is processed so that the frequency band of the input signal input from the signal input unit 510 is lowered to the low frequency side of the frequency band.
The extension unit 520 can process the input signal by any of the following two methods.
(A) The stretching unit 520 stretches the input signal in the time direction.
At this time, the extension unit 520 expands the section of the input signal, which is a signal of a predetermined pattern and is not a regulation signal, in the time direction so as to have a predetermined time.
For example, as shown by reference numeral (b) in FIG. 3, when a signal including the vibration waveform W2 and the regulation signal W3 is input, the extension unit 520 performs frequency analysis or pattern matching as described above. By performing the processing, the section D in which the regulation signal W3 exists is detected, and the signal of the remaining section (section S2) excluding the section D is extracted as the vibration waveform W2. Then, the extension unit 520 extends in the time axis direction so that the section S2 of the extracted vibration waveform W2 becomes the section S1. As a result, the vibration waveform W2 is extended in the time axis direction, so that the frequency of the vibration waveform W2 is lowered to the low frequency side. As a result, even if the signal is on the low frequency side that is not the frequency band to be transmitted, it is compressed by the signal processing device 10 and then expanded by the signal processing device 50 to vibrate from the vibration waveform W2 in the signal processing device 50. It can be restored to the waveform W1 and used in the subsequent stage.

In the compression process by the signal processing unit 120 of the signal processing device 10, the decompression unit 520 expands the data missing when the signal whose vibration waveform is compressed in the time direction is decompressed. You may want to interpolate based on the context of the time.

Here, the compression condition and the decompression condition can be shared between the signal processing device 10 and the signal processing device 50 so that the decompression processing corresponding to the compression processing performed in the signal processing device 10 can be executed in the signal processing device 50. I just need to be there. For example, the pattern of the regulation signal W3, the length of the section S1 in the time direction, the length of the section S2 in the time direction, the compression ratio R, whether the regulation signal W3 is arranged before or after the vibration waveform W2, etc. The condition of the above may be shared by the signal processing device 10 and the signal processing device 50.

(B) The extension unit 520 has a conversion unit 521, and extends (restores) the input signal by a method different from the above-mentioned extension in the time direction (for example, a method of frequency shifting in the frequency space). In this case, the function of the conversion unit 521 is used.
The conversion unit 521 performs inverse Fourier transform on the input signal stretched by the stretching unit 520. When the conversion unit 521 is used, the expansion unit 520 processes the input signal so as to shift it in the negative direction (toward the low frequency range) in the frequency space. Then, the extension unit 520 converts the input signal shifted to the low frequency side into a time-space input signal by performing an inverse Fourier transform by the conversion unit 521.

A more specific description will be given with reference to FIG.
When the vibration waveform W6 shown by the reference numeral (b) in FIG. 5 is input, the extension unit 520 shifts the frequency of the vibration waveform W6 to the low frequency side by the amount of shift S. As a result, the vibration waveform W6 shifts the entire signal so that the lowest frequency having the signal strength is f2, but the frequency becomes f1. Then, the extension unit 520 can convert the input signal from the frequency space to the time space by the conversion unit 521.
As a result, the vibration waveform W5 can be obtained from the vibration waveform W6, and further, by converting the vibration waveform W5 into a time-space signal, the frequency component on the low frequency side included before compression (before processing) can be obtained. The signal can be used in the transmitted subsequent equipment.

Returning to FIG. 6, the output unit 530 has a signal corresponding to the frequency band (fourth signal) and a signal on the lower frequency side than the frequency band (fifth signal) among the signals processed by the extension unit 520. ) And at least one of the signals is output. Here, the output unit 530 is one of a fourth signal only, a fifth signal only, and a signal including both the fourth signal and the fifth signal, depending on the signal required by the equipment in the subsequent stage. May be selected and output to the subsequent stage.
Further, when the input signal is a sound signal, the output unit 530 outputs a signal corresponding to the frequency band as a sound signal, and the vibration waveform is a signal that generates vibration for a signal on the low frequency side of the frequency band. Output as.

FIG. 7 is a sequence diagram illustrating the operation of the signal processing system 1 in FIG. Here, a case where a vibration signal is transmitted from the signal processing device 10 to the signal processing device 50 via the wireless communication device 30 and the wireless communication device 40 will be described.
The signal input unit 110 of the signal processing device 10 inputs a vibration signal input from the outside (step S101), and the signal processing unit 120 of the signal processing device 10 receives a frequency component on the low frequency side with respect to the input vibration signal. Is processed so as to be within the frequency band to be transmitted (step S102). This processing may be compression in the time direction, or may be processing in which the frequency is shifted according to the shift amount S after the vibration signal is converted into the frequency space. Then, the output unit 130 of the signal processing device 10 outputs the processed vibration signal to the wireless communication device 30 (step S103). Here, when the wireless communication device 30 cannot transmit the vibration signal represented in the frequency space by wireless communication, the output unit 130 performs the inverse Fourier transform of the vibration signal represented in the frequency space to time. After converting to space, it may be output to the wireless communication device 30.

When the wireless communication device 30 inputs the vibration signal output from the signal processing device 10 (step S301), the wireless communication device 30 wirelessly transmits the vibration signal to the wireless communication device 40 which is the communication partner (step S302). Here, since the signal on the low frequency side of the vibration signal is a signal in a frequency band within the frequency band that can be transmitted by the wireless communication device 30, at the stage of transmitting from the wireless communication device 30 to the wireless communication device 40, There is no loss of frequency components on the low frequency side.

When the wireless communication device 40 receives the vibration signal transmitted from the wireless communication device 30 (step S401), the wireless communication device 40 outputs the received vibration signal to the signal processing device 50 (step S402).

When the signal processing device 50 receives the vibration signal from the wireless communication device 40 (step S501), the signal processing device 50 processes the vibration signal so that the frequency component of the received vibration signal is on the low frequency side (step S502), and the processed vibration. The signal is output to the device in the subsequent stage (step S503). The processing in step S502 may be expansion of the signal in the time axis direction as long as it corresponds to the compression method processed in the signal processing device 10 in step S102, or the frequency may be extended to the low frequency side in the frequency space. It may be a process of shifting. Further, when the process of shifting the frequency to the low frequency side in the frequency space is performed, the output unit 530 of the signal processing device 50 performs the inverse transform Fourier transform on the vibration signal to convert the vibration signal into time. After converting to space, it may be output to the device in the subsequent stage.

FIG. 8 is a schematic functional block diagram showing the configuration of the signal processing device 10A, which is another embodiment of the signal processing device 10. The same reference numerals are given to the functions common to the signal processing apparatus 10, and the description thereof will be omitted.
The signal input unit 110A includes a vibration signal input unit 111, a content acquisition unit 112, and a signal synthesis unit 113.
The vibration signal input unit 111 inputs a signal having a frequency lower than the frequency band to be transmitted. For example, a signal corresponding to the vibration to be output is input to the vibration signal input unit 111 from the outside.
The content acquisition unit 112 is a signal in the frequency band to be transmitted. This signal may be data capable of outputting sound, such as audio data encoded by collecting a human voice with a microphone or the like, music data representing the sound of a music, sound effects, and environmental sounds. It may be acoustic data representing. The content acquisition unit 112 may acquire existing content, for example.

By synthesizing the signal input from the vibration signal input unit 111 and the signal input from the content acquisition unit 112, the signal synthesis unit 113 has a signal in the frequency band to be transmitted and a band lower than the frequency band to be transmitted. Generate a signal that includes a signal.

In this way, the signal processing device 10A can additionally add a vibration signal input from the outside to the content. Therefore, even if there is content that does not include a signal in a band lower than the frequency band to be transmitted, the signal processing unit 120 processes the content after adding a vibration signal to the content. be able to.
The signal output from the signal processing device 10A may be output to a signal processing device connected to the device to be transmitted via a wireless communication device or the like, or may be stored in the storage device 20.

FIG. 9 is a schematic functional block diagram showing the configuration of the signal processing device 50A, which is another embodiment of the signal processing device 50. The same reference numerals are given to the functions common to the signal processing apparatus 10, and the description thereof will be omitted.
When the input signal input from the signal input unit 510 is a sound signal of a plurality of channels, the signal separation unit 515 separates each channel, outputs the signal of the first channel to the extension unit 520, and outputs the signal of the first channel to the extension unit 520. The signal is output to the signal interpolation unit 525 and the output unit 530.
The first channel is, for example, a signal containing a frequency component in a frequency band lower than the frequency band to be transmitted. The second channel is a signal that is not stretched by the stretcher 520, and is, for example, a signal that does not contain a low frequency component.

The signal interpolation unit 525 interpolates the signal obtained from the extension unit 520 based on the signal obtained from the signal separation unit 515 and outputs the signal to the output unit 530. Here, when the signal stretched by the stretching unit 520 is compressed so as to include the low frequency component, the high frequency component is lost because it does not fit in the frequency band to be transmitted. There is. In such a case, the crossover frequency is predetermined based on the frequency that can be missing, and the signal interpolation unit 525 sets a signal on the high frequency side of the signal obtained from the extension unit 520 based on the crossover frequency. Of the signals obtained from the separation unit 515, the signal on the higher frequency side than the crossover frequency is synthesized. As a result, even if the frequency component on the high frequency side is missing in the signal stretched by the stretching unit 520, it is possible to interpolate using the signal of the frequency component on the high frequency side obtained in another channel. .. Here, since the signal of another channel is used for interpolation, it does not necessarily return to the original signal completely, but the sound generated by the fact that a specific high frequency component is always missing only in a certain channel is heard. It is possible to reduce the sense of incongruity on the part.
The output unit 530 outputs the signal interpolated by the signal interpolation unit 525 and the signal obtained from the signal separation unit 515 to a subsequent device. As a result, not only can each signal of the plurality of channels be output, but also a signal having a frequency lower than the frequency band to be transmitted can be included in the signal of any channel and transmitted to the subsequent stage.

In the above-described embodiment, the signal on the low frequency side is processed so as to fit in the processing target region, and the signal is restored and output by the apparatus on the reproduction side. As a result, the signal in the audible band can be output as sound by outputting it from an output device such as a speaker. Then, even a signal having a frequency lower than the audible band can be received and reproduced on the reproduction side without being lost from the processing target area. This makes it possible to output a signal having a frequency lower than the audible band as vibration.
As a result, the low-frequency side signal is not transmitted in a general system, but the low-frequency side signal can also be transmitted in the above-mentioned signal processing system, so that the low-frequency side signal is transmitted in the subsequent equipment. Can be output.

Thereby, for example, when the above-mentioned signal processing system is applied to an entertainment device such as a game machine, it is possible to transmit the vibration according to the progress of the game, the scene of the game, and the operation content to the user. .. When the vibration device is provided in the controller of the game, the vibration can be transmitted to the hand of the user holding the controller. When the vibrating device is provided on the seat on which the user playing the game is seated, the vibration device is provided to the user from at least one of the seat back, the seat surface, the footrest, etc., according to the progress of the game and the like. Vibration can be transmitted.

Further, for example, even when playing back a content in which a live music performance is recorded, a waveform signal corresponding to the vibration on the low frequency side generated at the live venue can also be transmitted to the playback side. On the reproduction side, the signal on the low frequency side can be reproduced as vibration. As a result, the vibration corresponding to the signal including the low frequency component can be transmitted to the user, so that not only the vibration heard as sound but also the vibration transmitted to the body at the live venue (low frequency component can be transmitted. Since the vibration) can also be transmitted on the playback side, even if the content is played back, the feeling of presence and immersion can be improved by improving the live feeling. In addition, when the content is a movie, by including the vibration according to the scene of the movie as a signal in the content, for example, the vibration felt by the characters and characters appearing in the movie can be transmitted to the viewer. Since it can be given, it is possible to provide content with an improved sense of reality.

Further, in the above-described embodiment, the existing content is processed so as to be included in the processing target area together with the vibration signal, so that the existing content is utilized to create the content including the vibration signal. Is possible. As a result, the sound signal and the vibration signal can be taken out and reproduced by restoring the content including the vibration signal by downloading the content from the server or reading the content from the recording medium.

Such a vibrating device may be, for example, a device that can be attached to a chair (seat). For example, it may be attached to at least one of a seat surface, a backrest, a headrest, a hood rest, and the like.

Further, according to the above-described embodiment, even when recording / transmitting using existing voice processing technology (recording / reproducing technology or transmission technology), a vibration waveform that can be sensed by the skin is transmitted. Can be done. In addition, since vibration information can be processed using existing voice processing technology, standards such as hardware, parts, and formats can be standardized. Further, since the existing voice processing technology that is widely used can be used, the vibration waveform can be processed without changing the implementation of the core part of the processing.

Further, in the above-described embodiment, when the compression / decompression processing is performed in the time axis direction, it is not necessary to perform the Fourier transform processing or the inverse Fourier transform processing, so that the load of signal processing can be reduced. Real-time performance can be improved.

In the above-described embodiment, the signal processing device 10 and the signal processing device 10A have been described as devices different from the wireless communication device 30, but the signal processing device 10 or the signal processing device 10A is integrated with the wireless communication device 30. It may be built in. For example, it may be configured as any one of a smartphone, a PC, a tablet, and a mobile phone including the functions of the signal processing device 10 or the signal processing device 10A and the wireless communication device 30.
Further, in the above-described embodiment, the signal processing device 50 and the signal processing device 50A have been described as devices different from the wireless communication device 40, but the signal processing device 50 or the signal processing device 50A is integrated with the wireless communication device 40. It may be built in. For example, it may be configured as any one of a smartphone, a PC, a tablet, and a mobile phone including the functions of the signal processing device 50 or the signal processing device 50A and the wireless communication device 40.

The function of any one of the signal processing device 10, the signal processing device 50, and the signal processing device 10A in the above-described embodiment may be configured by a processing device such as a CPU (central processing unit) or a dedicated electronic circuit.
Further, the function of any one of the signal processing device 10, the signal processing device 50, and the signal processing device 10A in the above-described embodiment may be realized by a computer. In that case, the program for realizing this function may be recorded on a computer-readable recording medium, and the program recorded on the recording medium may be read by the computer system and executed. The term "computer system" as used herein includes hardware such as an OS and peripheral devices. Further, the "computer-readable recording medium" refers to a portable medium such as a flexible disk, a magneto-optical disk, a ROM, or a CD-ROM, or a storage device such as a hard disk built in a computer system. Further, a "computer-readable recording medium" is a communication line for transmitting a program via a network such as the Internet or a communication line such as a telephone line, and dynamically holds the program for a short period of time. It may also include a program that holds a program for a certain period of time, such as a volatile memory inside a computer system that serves as a server or a client in that case. Further, the above program may be for realizing a part of the above-mentioned functions, and may be further realized for realizing the above-mentioned functions in combination with a program already recorded in the computer system. It may be realized by using a programmable logic device such as FPGA (Field Programmable Gate Array).

Although the embodiments of the present invention have been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and includes designs and the like within a range that does not deviate from the gist of the present invention.

1 ... Signal processing system, 10 ... Signal processing device, 10A ... Signal processing device, 20 ... Storage device, 30 ... Wireless communication device, 40 ... Wireless communication device, 50 ... Signal processing device, 50A ... Signal processing device, 60 ... Drive Device, 110 ... signal input unit, 110A ... signal input unit, 111 ... vibration signal input unit, 112 ... content acquisition unit, 113 ... signal synthesis unit, 120 ... signal processing unit, 121 ... conversion unit, 130 ... output unit, 510 ... signal input unit, 515 ... signal separation unit, 520 ... extension unit, 521 ... conversion unit, 525 ... signal interpolation unit, 530 ... output unit

Claims (14)

Signal processing having a signal processing unit that processes the first signal, which is a signal included in the frequency band to be transmitted, and the second signal, which is a signal having a frequency lower than the frequency band, so as to fit in the frequency band. apparatus. The signal processing unit
The signal processing apparatus according to claim 1, wherein the first signal and the second signal are processed by compressing them in the time direction. The signal processing unit has a signal length corresponding to a difference between a signal length which is the length of the signal to be compressed in the time direction and a signal length which is the length of the signal after being compressed in the time direction in the time direction. The signal processing device according to claim 2, wherein the third signal, which is the signal of the above, is added to at least one of the front and back in the time direction of the compressed signal. It has a conversion unit that converts the first signal and the second signal into a signal in the frequency space by Fourier transforming the signal.
The signal processing device according to claim 1, wherein the signal processing unit shifts the frequency so that the signal in the converted frequency space fits in a wave number band to be transmitted. An extension part that is processed so that the frequency band of the input signal goes down to the low frequency side of the frequency band,
An output unit that outputs at least one of a signal corresponding to the frequency band and a signal on the lower frequency side of the frequency band among the processed signals.
A signal processing device having. The input signal is a sound signal and
The output unit
The signal processing device according to claim 5, further comprising outputting a signal corresponding to the frequency band as a sound signal and outputting as a vibration signal which is a signal for generating vibration for a signal on the lower frequency side than the frequency band. The extension part
The signal processing device according to claim 5 or 6, wherein the input signal is extended in the time direction. The extension part
In any one of claims 5 to 7, the non-applicable section of the input signal, which is a signal of a predetermined pattern and is not a regulation signal, is extended in the time direction so as to have a predetermined time. The signal processing device described. It has a conversion unit that performs inverse Fourier transform on the input signal stretched by the expansion unit.
The extension part
The signal processing device according to claim 5, wherein the input signal is processed so as to shift to the low frequency side in the frequency space. The signal processing device according to any one of claims 5 to 9.
A vibrating device having a vibrating portion that generates vibration based on a signal on the low frequency side of the frequency band obtained from the signal processing device. The signal processing device according to any one of claims 1 to 4.
The signal processing device according to any one of claims 5 to 9.
Signal processing system with. A program for operating a computer as the signal processing device according to any one of claims 1 to 9. The signal processing unit processes the first signal, which is a signal included in the frequency band to be transmitted, and the second signal, which is a signal having a frequency lower than the frequency band, so that the signal is contained in the frequency band. Method. The extension part is processed so that the frequency band of the input signal is lowered to the low frequency side of the frequency band.
A signal processing method in which an output unit outputs either a signal corresponding to the frequency band or a signal on the lower frequency side of the frequency band among the processed signals.

Images