Vibration signal generation apparatus, content reproduction system, and vibration signal generation program

Abstract

To generate appropriate vibration according to content that does not make a user feel uncomfortable or uncomfortable.SOLUTION: A vibration signal generation apparatus for generating a vibration signal based on a sound signal corresponding to content, the vibration signal generation apparatus extracts, from the sound signal, a signal in a vibration-corresponding band corresponding to vibration to be output to a user, thereby generating a vibration-corresponding band signal, extracts, from the sound signal, a signal in a predetermined compression control-preferred band, thereby generating a compression control-preferred band signal, and compresses the vibration-corresponding band signal in accordance with the signal intensity of the compression control-preferred band signal, thereby generating the vibration signal.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to a vibration signal generating device, a content playback system, and a vibration signal generating program. [Background technology]

[0002] Conventionally, a technology has been proposed that aims to improve the sense of realism of content by transmitting vibrations corresponding to the content being viewed by the user. For example, a technology is known in which a vibration signal is generated by extracting low-frequency components of an acoustic signal, and a vibrator is vibrated by the vibration signal, so that vibrations corresponding to the content are output to the user and experienced by the user, thereby improving the sense of realism (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-239043 Summary of the Invention [Problem to be solved by the invention]

[0004] However, there were issues such as users feeling uncomfortable with small vibrations generated based on low-volume acoustic signals that have low correlation with vibration, and similarly, users feeling uncomfortable with vibrations generated based on acoustic signals that are not rich in bass, such as voices (human voices) or the sounds of instruments such as guitars, which have low correlation with vibration.

[0005] In view of the above-mentioned problems, an object of the present invention is to provide a technology capable of generating appropriate vibrations according to content that do not cause a user to feel uncomfortable or unnatural. [Means for solving the problem]

[0006] An exemplary vibration signal generating device of the present invention is a vibration signal generating device that generates a vibration signal based on an audio signal corresponding to content, extracts a signal of a vibration-corresponding band corresponding to the vibration to be output to a user from the audio signal to generate a vibration-corresponding band signal, extracts a signal of a predetermined compression control preferred band from the audio signal to generate a compression control preferred band signal, and compresses the vibration-corresponding band signal according to the signal strength of the compression control preferred band signal to generate the vibration signal. [Effects of the Invention]

[0007] According to the present invention, the compression content of the vibration-corresponding band signal is determined based on the signal strength of the audio signal in the compression control suitable band (which becomes vibration in the compression control suitable band), which is correlated with the degree of adverse effect on the user (such as discomfort caused by output vibration). Therefore, it is possible to generate a vibration signal that suppresses adverse effects on the user (such as discomfort caused by small amplitude vibration generated based on a low volume audio signal). As a result, an appropriate vibration is output to the user. [Brief explanation of the drawings]

[0008] [Figure 1] Overall configuration diagram of a content playback system according to the present embodiment [Figure 2] A block diagram showing the configuration of the content playback device system of FIG. 1. [Figure 3] FIG. 2 is a perspective view showing an example of the configuration of a sheet having the vibrator of FIG. 1; [Figure 4] A block diagram showing the configuration of the vibration signal generating device of FIG. [Figure 5] FIG. 1 is an explanatory diagram illustrating an outline of a vibration signal generating method in a vibration signal generating device according to a first embodiment. [Figure 6] 1 is a flowchart showing a vibration signal generation process executed by the vibration signal generation device of the first embodiment. [Figure 7] FIG. 10 is a block diagram showing the configuration of a vibration signal generating device according to a second embodiment. [Figure 8] FIG. 10 is an explanatory diagram illustrating an outline of a vibration signal generating method in a vibration signal generating device according to a second embodiment. [Figure 9]10 is a flowchart showing a vibration signal generation process executed by a vibration signal generation device according to a second embodiment. [Figure 10] FIG. 10 is a block diagram showing the configuration of a vibration signal generating device according to a third embodiment. [Figure 11] FIG. 10 is an explanatory diagram illustrating an outline of a vibration signal generating method in a vibration signal generating device according to a third embodiment. [Figure 12] 10 is a flowchart showing a vibration signal generation process executed by a vibration signal generation device according to a third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the contents of the embodiments shown below.

[0010] <1. Content playback system> FIG. 1 is an overall configuration diagram of a content playback system 1 of this embodiment. FIG. 2 is a block diagram showing the configuration of the content playback device system of FIG. 1. In this embodiment, the content playback system 1 is a system that outputs sound and vibration to a user according to content to be played back. The content playback system 1 is applied to, for example, a vehicle V1. The content playback system 1 includes a content playback device 10, a surround device 20, a speaker 30, a vibration signal generation device 40, and a vibrator 50.

[0011] The content playback device 10 transmits, in accordance with the content to be played back, an acoustic signal acquired from the data of the content to a surround device 20 that plays back the sound and a vibration signal generating device 40 that generates vibrations. For example, the content playback device 10 reads acoustic data from a recording medium such as an optical disc, or acquires acoustic data distributed via the Internet or the like, and generates and outputs an acoustic signal based on the acoustic data.

[0012] The surround device 20 is a device that reproduces stereophonic sound according to the content to be reproduced, and performs surround processing on the sound signals of the content output by the content reproduction device 10 to generate surround signals for controlling the speakers 30 for sound reproduction. The surround device 20 and the speakers 30 are connected by wire via an amplifier 21S. Each surround signal output from the surround device 20 is power-amplified by each amplifier 21S. The power-amplified surround signal then drives each speaker 30 to output surround sound. Note that the surround device 20 may be built into the content reproduction device 10 as a content reproduction device with a surround function.

[0013] Each speaker 30 is installed in a position suitable for surround sound reproduction in the cabin of the vehicle V1. In the content playback system 1 of this embodiment, the speakers 30 include a speaker 31L installed in the front left door of the vehicle V1, a speaker 31R installed in the front right door, and a speaker 31C installed on the instrument panel at the front of the cabin. The speakers 30 also include a speaker 32L installed in the rear left door of the vehicle V1, a speaker 32R installed in the rear right door, and a speaker 32C installed on the back panel at the rear of the cabin. An amplifier 21S is provided individually for each of the six speakers 31L, 31R, 31C, 32L, 32R, and 32C, and amplifies the power of the surround signals for each speaker 30 and supplies them to each speaker. When describing the six speakers as a whole, they may be collectively referred to as "speakers 30."

[0014] The content reproduction system 1 may include a display device (not shown). In this case, the content reproduction device 10 transmits a video signal corresponding to the content to be reproduced to the display device, and causes the display device to display the video.

[0015] The vibration signal generating device 40 is a device that generates a control signal (vibration signal) for vibrating each vibrator 50 for vibration playback in accordance with the content to be played. The vibration signal generating device 40 and each vibrator 50 are connected by wire via each amplifier 21V. Each amplifier 21V power-amplifies each vibration signal to generate a vibrator drive signal, and outputs the vibrator drive signal to each vibrator 50, causing each vibrator 50 to vibrate.

[0016] Each vibrator 50 is provided on the seating surface (seat portion) of a seat (seat) Se of the vehicle V1. The vibrator 50 is configured by an electric vibration converter including, for example, an electric magnetic circuit, a piezoelectric element, and an electric cylinder. The vibrator 50 generates vibrations according to a vibration signal and outputs the vibrations to the user. In other words, the vibrator 50 generates vibrations according to the content to be played, based on the vibration signal output from the vibration signal generating device 40, and outputs the vibrations to the user.

[0017] Fig. 3 is a perspective view showing an example of the configuration of a seat Se having the vibrator 50 of Fig. 1. The seat Se has a seat portion Se1 and a backrest portion Se2.

[0018] The seat portion Se1 supports the buttocks and thighs of a user sitting on the seat Se. The seat portion Se1 has a surface member that forms its surface and a buffer member (cushion member) provided inside the surface member. The backrest portion Se2 extends upward so as to intersect with the upper surface of the seat portion Se1 and supports the back of a user sitting on the seat Se. The backrest portion Se2 has a surface member that forms its surface and a buffer member provided inside the surface member.

[0019] A plurality of vibrators 50 are mounted on the seat portion Se1 of the seat Se. The vibrators 50 are arranged inside or on the surface of the cushioning material of the seat portion Se1. The vibrators 50 may also be mounted on the backrest portion Se2 of the seat Se. For ease of explanation, only one seat Se of the vehicle V1 is depicted in FIG. 1, but in reality, the vibrators 50 can be mounted on a plurality of seats Se, and the sense of realism can be improved by vibrations when content is played in each seat.

[0020] In the content playback system 1 of this embodiment, the vibrators 50 include a vibrator 51L on the front left side of the seat portion Se1 of the seat Se, a vibrator 51R on the front right side, a vibrator 52L on the rear left side, and a vibrator 52R on the rear right side. An amplifier 21V is provided for each of the four vibrators 51L, 51R, 52L, and 52R, and supplies a vibrator drive signal to each vibrator 50 by power-amplifying an input vibration signal, thereby driving each vibrator 50. Note that when describing all four vibrators, they may be collectively referred to as "vibrators 50." Also, while FIG. 3 shows an example in which four vibrators 50 are provided for one seat Se, the number of vibrators 50 may be three or less, or five or more.

[0021] <2.Vibration signal generation device> <2-1. Overview of the vibration signal generator> Fig. 4 is a block diagram showing the configuration of the vibration signal generating device 40 of Fig. 1. Fig. 4 shows components necessary for explaining the features of this embodiment, and omits the description of general components.

[0022] The vibration signal generating device 40 includes a communication unit 41 , a storage unit 42 , and a controller 43 .

[0023] The communication unit 41 is an interface for communicating data with other devices (the content playback device 10, the vibrator 50) via a communication network. The communication unit 41 includes a communication device for performing wired communication and wireless communication with other devices. The wireless communication device is configured, for example, by a transmission / reception device for a mobile telephone network of 5G communication (fifth generation mobile communication system).

[0024] The storage unit 42 includes a volatile memory and a non-volatile memory, and stores various information necessary for content playback processing. The volatile memory is, for example, a random access memory (RAM). The non-volatile memory is, for example, a read-only memory (ROM), a flash memory, or a hard disk drive. The non-volatile memory stores programs and data that can be read by the controller 43. At least some of the programs and data stored in the non-volatile memory may be obtained from another computer device connected by wire or wirelessly, or from a portable recording medium.

[0025] The storage unit 42 stores a vibration signal generation program 421, a vibration control data table 422, and a vibration compression data table 423. The contents of these programs, data tables, etc. stored in the storage unit 42 will be described separately. Furthermore, the storage unit 42 stores data tables, etc. (not shown) for various processes.

[0026] The controller 43 is composed of a processor that performs arithmetic processing and the like, and controls various operations in the vibration signal generation device 40. The processor is composed of, for example, a CPU (Central Processing Unit). The controller 43 executes a vibration signal generation program 421 stored in the storage unit 42 to perform content playback processing (vibration playback processing). When playing back content, the controller 43 appropriately performs necessary data communication with the content playback device 10 and the surround device 20 to adjust the timing and levels of vibration playback, sound playback, and video playback. The vibration signal generation program 421 includes various programs that realize various functions of the vibration signal generation device 40.

[0027] <2-2. Overview of vibration signal generation method> Next, a description will be given of a vibration signal generation method for the vibrator 50. When the vibrator 50 provided on the sheet Se outputs vibration to the user, the vibration signal generation device 40 performs compression processing on the vibration signal of the vibrator 50 in order to suppress output of vibration generated based on a low-volume acoustic signal that is not suitable for the user to experience. The vibration signal generation method for the vibrator 50 is continuously realized in real time when content is being played back.

[0028] Fig. 5 is an explanatory diagram showing an outline of a vibration signal generation method in the vibration signal generation device 40 of Example 1. The vibration signal generation method in the vibration signal generation device 40 shown in Fig. 5 is a method for generating a vibration signal using an acoustic signal with an appropriate intensity as an acoustic signal used to generate vibration in content.

[0029] The vibration signal generating device 40 (vibration extracting unit 432) extracts a vibration-corresponding band signal of a vibration-corresponding band Bv from the audio signal received from the content reproducing device 10. The vibration-corresponding band Bv is a frequency band suitable for vibration felt by the user, and is a frequency range in which sensitivity to vibration is high in terms of human tactile sensation characteristics. Specifically, it is a frequency band of 30 to 130 Hz, which is a so-called deep bass frequency band for audio signals. The vibration signal generating device 40 generates a vibration signal based on the vibration-corresponding band signal extracted from the audio signal.

[0030] The vibration signal generating device 40 (determination unit 433) determines whether the signal strength of the vibration-corresponding band signal is less than a preset threshold. If the signal strength of the vibration-corresponding band signal is less than the preset threshold, the vibration signal generating device 40 compresses (attenuates) the vibration-corresponding band signal. The vibration-corresponding band signal may be blocked (signal strength 0). In other words, according to this processing, the vibration-corresponding band signal is converted (compressed) into a vibration signal in accordance with the vibration compression characteristic VCa shown in FIG. 5.

[0031] The vibration compression characteristics of the vibration compressor 434 may be such that the input signal is compressed strongly (high compression level) in a range where the input signal is small, and compressed weakly (low compression level (or no compression is possible)) in a range where the input signal is large, as shown by the vibration compression characteristics VCb-VCc in Fig. 5. Such compression characteristics may be determined appropriately through experiments (sensitivity tests, etc.).

[0032] 5, the vibration compression characteristic VCa is a compression characteristic in which the output-input signal intensity ratio is a small fixed value (e.g., 0.5) when the input signal intensity is below the threshold, and a large fixed value (e.g., 1) when the input signal intensity is equal to or greater than the threshold. The vibration compression characteristic VCb is a compression characteristic in which the output-input signal intensity ratio is 0 when the input signal intensity is below the threshold, and a fixed value (e.g., 1) when the input signal intensity is equal to or greater than the threshold, with the threshold being used as the input reference value (the input signal level is shifted negative by the threshold amount). The vibration compression characteristic VCc is a compression characteristic in which the output-input signal intensity ratio in the vibration compression characteristic VCb when the input signal intensity is equal to or greater than the threshold is an appropriate variable.

[0033] Furthermore, these signal processes can be realized by converting these signals into digital signals and performing appropriate digital signal processing (amplification and attenuation processing, filtering processing, etc.) on these digital signals using a digital signal processor. Specifically, the compression rate of the vibration compressor 434 is changed according to the signal level of the vibration-corresponding band signal (the signal level of the vibration-corresponding band signal and the compression rate are stored in association with each other in a vibration compression table in the storage unit 42), and the vibration-corresponding band signal is compressed to generate a vibration signal.

[0034] In this way, the vibration signal generating device 40 generates a vibration signal based on the sound signal of the content. The generated vibration signal undergoes necessary processing such as power amplification and is output to the vibrator 50 as a vibrator drive signal.

[0035] The vibration signal generating device 40 will now be described in further detail.

[0036] <2-3. Details of the vibration signal generator> 4, the controller 43 includes, as its functions, an acquisition unit 431, a vibration extraction unit 432, a determination unit 433, a vibration compression unit 434, and an output unit 435. In this embodiment, the functions of the controller 43 are realized by a processor executing arithmetic processing in accordance with a vibration signal generation program 421 and a vibration control data table 422 stored in the storage unit 42.

[0037] The acquisition unit 431 acquires (receives) an acoustic signal corresponding to the content to be reproduced from the content reproduction device 10 via the communication network and the communication unit 41.

[0038] The vibration extraction unit 432 extracts a signal to be processed to generate a vibration signal for driving the vibrator 50, based on the acoustic signal acquired by the acquisition unit 431. More specifically, the vibration extraction unit 432 extracts a vibration-corresponding band signal of a vibration-corresponding band Bv corresponding to vibration from the acoustic signal. The vibration-corresponding band Bv is a frequency band from 30 Hz to 130 Hz, for example (see FIG. 5). Data related to the bandwidth of the vibration-corresponding band Bv is set in advance and stored in the vibration control data table 422. The vibration extraction unit 432 uses this stored data to extract the vibration-corresponding band signal through filtering processing by a digital signal processor or the like. The vibration-corresponding band signal generated (extracted) by the vibration extraction unit 432 is input to the determination unit 433 and the vibration compression unit 434.

[0039] The determination unit 433 determines the signal strength of the vibration-corresponding band signal. Specifically, if the signal strength of the vibration-corresponding band signal is less than a predetermined threshold, the determination unit 433 determines to compress the vibration-corresponding band signal generated by the vibration extraction unit 432. Data related to the threshold is preset and stored in the vibration control data table 422.

[0040] That is, in this embodiment, when the signal strength of a signal (vibration-corresponding band signal) in the frequency band from 30 Hz to 130 Hz, which is the vibration-corresponding band Bv in the acoustic signal, is less than the threshold, it is determined to perform compression processing of the vibration-corresponding band signal. On the other hand, when the signal strength of the vibration-corresponding band signal is equal to or greater than the threshold, it is determined not to perform compression processing of the vibration-corresponding band signal. Information on whether compression processing of the vibration-corresponding band signal is performed is sent to the vibration compression unit 434.

[0041] When the determination unit 433 determines to perform compression processing of the vibration-corresponding band signal, the vibration compressor 434 compresses the vibration-corresponding band signal to generate a vibration signal. The compression of the vibration-corresponding band signal is performed based on compression characteristics (compression rate, etc.) that are set in advance based on experiments or the like and stored in the vibration compression data table 423. The compression characteristics may be variable values ​​(characteristics) based on the type of content, scenes in the content, etc., or may be preset constant values ​​(characteristics). Note that when the determination unit 433 determines not to perform compression processing of the vibration-corresponding band signal, the vibration compressor 434 does not compress the vibration-corresponding band signal, and generates the vibration-corresponding band signal as a vibration signal. The signal vibration generated by the vibration compressor 434 (the vibration signal generated by compression processing or the vibration signal generated without compression processing) is input to the output unit 435.

[0042] The output unit 435 receives the vibration signal output from the vibration compression unit 434 and performs necessary processing on the received vibration signal (for example, correction processing to correct errors in the characteristics of each vibrator 50, etc.). The output unit 435 outputs the vibrator drive signal to the vibrator 50 via an amplifier 21V that performs power amplification required to drive the vibrator 50.

[0043] According to the above configuration, a vibration-corresponding band signal of a frequency band (vibration-corresponding band Bv) suitable for a user's bodily sensation is extracted from the sound signal of the content. When the signal strength of the vibration-corresponding band signal is equal to or greater than a threshold, the vibration-corresponding band signal becomes a vibration signal, and the vibration signal is subjected to power amplification, etc., required to drive the vibrator, thereby driving the vibrator. On the other hand, when the signal strength of the vibration-corresponding band signal is less than the threshold, the vibration-corresponding band signal is compressed to become a vibration signal, and the vibration signal is subjected to power amplification, etc., required to drive the vibrator, thereby driving the vibrator. In other words, vibrations generated based on small sound signals that are not suitable for a user's bodily sensation are suppressed from being output to the user. As a result, it is possible to output (communicate) appropriate vibrations suitable for the content to the user.

[0044] <2-4. Example of content playback device operation> 6 is a flowchart showing a vibration signal generation process executed by the vibration signal generation device 40 (controller 43) of Example 1. The operation according to this flowchart is realized by a computer program (vibration signal generation program 421) executed by the controller 43 (a computer constituting the controller 43).

[0045] A computer program that causes a computer device to implement the vibration signal generation method according to this embodiment is installed in a computer device such as the vibration signal generation device 40 to implement the various functions described above. Furthermore, such a computer program is provided to the computer device via a computer-readable non-volatile recording medium. For example, an optical disk or the like on which the computer program is recorded is distributed and sold, or a computer program stored on a hard disk or the like of a server device is distributed and sold via an internet environment. Furthermore, the computer program that causes a computer device to implement the calibration method according to this embodiment may consist of only one program, or may consist of multiple programs.

[0046] The process shown in FIG. 6 is repeatedly executed when the content playback system 1 (content playback device 10, surround device 20, speaker 30, vibration signal generating device 40, vibrator 50) is running and content is being played by the content playback device 10.

[0047] In step S101, the controller 43 (acquisition unit 431) acquires (receives) an audio signal corresponding to the content to be reproduced from the content reproduction device 10, and proceeds to step S102. The audio signal data of the acquired content is stored in a data table of the storage unit 42 as necessary.

[0048] In step S102, the controller 43 (vibration extraction unit 432) extracts a vibration-corresponding band signal of the vibration-corresponding band Bv from the acoustic signal acquired in step S101 (acquired by the acquisition unit 431), and proceeds to step S103. The extracted vibration-corresponding band signal (acoustic signal data) is stored in the storage unit 42 as necessary.

[0049] In step S103, the controller 43 (determination unit 433) determines whether to compress the vibration-corresponding band signal, and if so, proceeds to step S104, and if not, proceeds to step S105. In detail, if the signal strength of the vibration-corresponding band signal is less than a predetermined threshold, the controller 43 (determination unit 433) determines to compress the vibration-corresponding band signal and proceeds to step S104. On the other hand, if the signal strength of the vibration-corresponding band signal is equal to or greater than the predetermined threshold, the controller 43 (determination unit 433) determines not to compress the vibration-corresponding band signal, and proceeds to step S105, treating the vibration-corresponding band signal as a vibration signal.

[0050] In step S104, the controller 43 (vibration compressor 434) compresses the vibration-corresponding band signal to generate a vibration signal, and then proceeds to step S105. The vibration-corresponding band signal is compressed based on the compression characteristics stored in the vibration compression data table 423.

[0051] In step S105, the controller 43 (output unit 435) outputs the vibration signal as a vibrator drive signal to the vibrator 50 via the amplifier 21V that performs power amplification, and ends the processing in Fig. 6. The vibrator 50 vibrates in response to the vibration signal generated by the vibration signal generating device 40.

[0052] The vibration signal (control signal) of the vibrator 50 by the vibration signal generator 40 needs to be generated in real time during content playback. For this reason, the process shown in FIG. 6 is executed repeatedly at high speed during content playback so that the vibration does not appear unnatural. Considering human sensitivity to vibration, it tends to be slower than sensitivity to audio and video. For this reason, the repetition interval may be appropriately extended to form a vibration signal by applying a low-pass filter to the audio signal.

[0053] <3. Example 2> Next, a vibration signal generating device 40 of Example 2 will be described. The configuration of the vibration signal generating device 40 of Example 2 is the same as the configuration of the vibration signal generating device 40 of Example 1 described above (see FIG. 4). Furthermore, the vibration signal generating method of Example 2 (see FIG. 8) is basically similar to the vibration signal generating method of Example 1 described above (see FIG. 5). Therefore, in the following, descriptions of the configurations and processing steps common thereto will be omitted.

[0054] <3-1. Method for generating a vibration signal from a vibrator in the second embodiment> Fig. 7 is a block diagram showing the configuration of a vibration signal generator 40 of Example 2. Fig. 8 is an explanatory diagram showing an outline of a vibration signal generation method in the vibration signal generator 40 of Example 2. As shown in Fig. 7, the vibration extraction unit 432 of the controller 43 of the vibration signal generator 40 of Example 2 includes, as its functions, a vibration-corresponding band signal extraction unit 432a and a compression control suitable band signal extraction unit 432b.

[0055] The vibration signal generating device 40 of the second embodiment uses an acoustic signal in a compression control suitable band Bc on the lower frequency side of the acoustic signal (hereinafter referred to as a compression control suitable band signal) instead of a vibration corresponding band signal (a signal in a vibration corresponding band Bv in an acoustic signal) to determine whether to compress the vibration corresponding band signal or to select a compression processing method for the vibration corresponding band signal. This is based on the idea that, in terms of human tactile characteristics (vibration sensitivity), small amplitude vibrations based on small acoustic signals on the low frequency side of the vibration corresponding band signal (small amplitude vibrations on the low frequency side in the vibration corresponding band Bv) can have a large adverse effect (uncomfortable feeling, etc.), and therefore, determining the compression processing method using an acoustic signal in the compression control suitable band Bc will enable more appropriate control.

[0056] The vibration signal generating device 40 (the vibration-corresponding band signal extracting unit 432a of the vibration extracting unit 432) extracts a vibration-corresponding band signal of the vibration-corresponding band Bv from the acoustic signal received from the content reproducing device 10. In this embodiment, the vibration-corresponding band Bv is, for example, a frequency band from 30 Hz to 130 Hz (see FIG. 8).

[0057] Furthermore, the vibration signal generator 40 (the compression control suitable band signal extracting unit 432b of the vibration extracting unit 432) extracts from the acoustic signal a compression control suitable band signal of a compression control suitable band Bc, which is a frequency band lower than the vibration-corresponding band Bv. In this embodiment, the compression control suitable band Bc is, for example, a frequency band from 30 Hz to 100 Hz (see FIG. 8).

[0058] The vibration signal generator 40 (determination unit 433) determines whether the signal strength of the compression control suitable band signal is less than a preset threshold. That is, the vibration signal generator 40 determines whether or not to compress the vibration-corresponding band signal, or the compression processing method, based on the signal strength of the compression control suitable band Bc, which is lower than the vibration-corresponding band Bv in the acoustic signal.

[0059] When the signal strength of the compression control suitable band signal is less than a preset threshold, the vibration signal generating device 40 (vibration compression unit 434) compresses the vibration-corresponding band signal to generate a vibration signal. On the other hand, when the signal strength of the compression control suitable band signal is equal to or greater than a preset threshold, the vibration signal generating device 40 (vibration compression unit 434) does not compress the vibration-corresponding band signal and generates it as a vibration signal.

[0060] In addition, the vibration signal generating device 40 (vibration compression unit 434) may generate a vibration signal by compressing the vibration-corresponding band signal with compression characteristics according to the signal strength of the compression control suitable band signal (the smaller the signal strength of the compression control suitable band signal, the higher the compression rate).

[0061] In this way, the vibration signal generating device 40 generates a vibration signal based on the sound signal of the content. The generated vibration signal is subjected to necessary processing such as power amplification, and is output to the vibrator 50 as a vibrator drive signal.

[0062] According to the above configuration, the compression content of the vibration-corresponding band signal is determined based on the signal strength of the sound signal in the compression control suitable band Bc (which becomes vibration for the compression control suitable band Bc), which is correlated with the degree of adverse effect on the user (such as discomfort caused by output vibration). Therefore, it is possible to generate a vibration signal that suppresses adverse effects on the user (such as discomfort caused by small-amplitude vibration generated based on a low-volume sound signal). As a result, an appropriate vibration is output to the user.

[0063] <3-2. Example of Operation of Content Reproducing Device in Second Embodiment> 9 is a flowchart showing a vibration signal generation process executed by the vibration signal generation device 40 (controller 43) of Example 2. The operation according to this flowchart is realized by a computer program (vibration signal generation program 421) executed by the controller 43 (a computer constituting the controller 43). Note that, in the following, processing steps common to the operation flow (see FIG. 6) described in Example 1 are assigned the same reference numerals, and description thereof will be omitted.

[0064] In steps S101 and S102 of the process shown in FIG. 9, the controller 43 (vibration extraction unit 432) extracts a vibration-corresponding band signal of the vibration-corresponding band Bv from the acoustic signal acquired by the acquisition unit 431, and then proceeds to step S201.

[0065] In step S201, the controller 43 (vibration extraction unit 432) extracts a compression control suitable band signal of the compression control suitable band Bc from the acoustic signal acquired in step S101 (acquired by the acquisition unit 431), and proceeds to step S202. The compression control suitable band Bc is a frequency band lower than the vibration-corresponding band Bv. In detail, for example, while the vibration-corresponding band Bv is a frequency band from 30 Hz to 130 Hz, the compression control suitable band Bc is a frequency band from 30 Hz to 100 Hz.

[0066] In step S202, the controller 43 (determination unit 433) determines whether or not to compress the vibration-corresponding band signal, and if so, proceeds to step S104, or if not, proceeds to step S105. More specifically, if the signal strength of the compression control suitable band signal is less than a predetermined threshold, the controller 43 (determination unit 433) determines to compress the vibration-corresponding band signal and proceeds to step S104. On the other hand, if the signal strength of the compression control suitable band signal is equal to or greater than the predetermined threshold, the controller 43 determines not to compress the vibration-corresponding band signal, and proceeds to step S105, treating the vibration-corresponding band signal as a vibration signal.

[0067] Thereafter, in step S104, the controller 43 compresses the vibration-corresponding band signal to generate a vibration signal, and in step S105 outputs the vibration signal (if step S104 is bypassed, the uncompressed vibration-corresponding band signal is used as the vibration signal) to the vibrator 50 as a vibrator drive signal via the amplifier 21V, which performs power amplification, and ends the processing related to Figure 9.

[0068] <4. Example 3> Next, a vibration signal generating device 40 of Example 3 will be described. The configuration of the vibration signal generating device 40 of Example 3 (see FIG. 10) is basically similar to the configuration of the vibration signal generating device 40 of Example 1 (see FIG. 4) described above. Furthermore, the vibration signal generating method of Example 3 (see FIG. 11) is basically similar to the vibration signal generating method of Example 2 (see FIG. 8) described above. Therefore, in the following, descriptions of the configurations and processing steps common thereto will be omitted.

[0069] <4-1. Method for generating a vibration signal from a vibrator in the third embodiment> Fig. 10 is a block diagram showing the configuration of a vibration signal generator 40 of Example 3. Fig. 11 is an explanatory diagram showing an outline of a vibration signal generation method in the vibration signal generator 40 of Example 3. As shown in Fig. 10, the controller 43 of the vibration signal generator 40 of Example 3 includes, as its functions, a shift unit 436 (a shift control unit 436a and a shift processing unit 436b).

[0070] The shift unit 436 controls frequency shift processing to shift the frequency band of the acoustic signal acquired by the acquisition unit 431. Depending on the type of content, there may be many acoustic signals with low signal strength in the vibration-corresponding band. In this case, not much vibration is output to the user, and the vibration output effect, such as improving the sense of realism, is not fully exerted. Therefore, a vibration signal is generated from a signal obtained by frequency-shifting the acoustic signal to the lower frequency side (hereinafter referred to as a frequency-shifted signal).

[0071] For example, the vibration-corresponding band Bv suitable for vibration is 30 Hz to 130 Hz. Therefore, if the peak frequency of the acoustic signal in the frequency band of 30 Hz to 260 Hz exceeds 130 Hz, it is determined that the signal strength of the vibration-corresponding band signal in the acoustic signal is insufficient. As a result, the frequency shift process is performed to lower the frequency of the acoustic signal by one octave, that is, to halve the frequency of the acoustic signal. Data related to such frequency shift process (shift execution conditions, shift amount, etc.) are set to appropriate values ​​based on experiments, etc., and stored in the vibration control data table 422.

[0072] 11, for example, in this embodiment, the vibration signal generating device 40 (shift control unit 436a of the shift unit 436) performs frequency analysis processing on the acoustic signal. If the shift control unit 436a determines as a result of the analysis processing that the signal strength in the vibration-corresponding band Bv is insufficient, it causes the shift processing unit 436b of the shift unit 436 to perform frequency shift processing on the acoustic signal and generate a shifted acoustic signal.

[0073] Specifically, for example, suppose that the shift control unit 436a determines that the signal strength of the vibration-corresponding band signal is insufficient for an acoustic signal having a peak at 150 Hz in the frequency band from 30 Hz to 260 Hz. In this case, the shift control unit 436a causes the shift processing unit 436b to perform frequency shift processing on the acoustic signal to lower the frequency by one octave (halve the frequency) and generate a shifted acoustic signal. As a result of this frequency shift processing, the shifted acoustic signal becomes an acoustic signal having a peak at approximately 75 Hz.

[0074] The vibration signal generating device 40 (the compression control suitable band signal extracting unit 432b of the vibration extracting unit 432) extracts the signal of the vibration corresponding band Bv from the shifted acoustic signal to generate the vibration corresponding band signal. In this embodiment, the vibration corresponding band Bv is, for example, a frequency band from 30 Hz to 130 Hz.

[0075] Furthermore, the vibration signal generator 40 (compression control suitable band signal extraction unit 432b of the vibration extraction unit 432) extracts a compression control suitable band signal of a compression control suitable band Bc, which is a frequency band lower than the vibration-corresponding band Bv, from the shifted acoustic signal. When the acoustic signal is not frequency-shifted, the compression control suitable band Bc is a frequency band (referred to as a basic compression control suitable band) suitable for determining whether compression processing is necessary or for selecting a compression processing method. In this embodiment, the compression control suitable band Bc is, for example, a frequency band from 30 Hz to 100 Hz.

[0076] Furthermore, when the frequency shift of the acoustic signal is performed, the compression control suitable band Bc is set to a shift compression control suitable band obtained by shifting the basic compression control suitable band by the frequency shift amount of the acoustic signal. For example, in this embodiment, if the frequency shift amount is one octave, the shift compression control suitable band is 15 Hz to 50 Hz. Note that the shift unit 436 transmits compression control suitable band information (whether or not a frequency shift is performed, information on the vibration-corresponding band Bv, etc.) for determining the vibration-corresponding band Bv to the compression control suitable band signal extraction unit 432b.

[0077] That is, when a frequency shift is performed to shift the frequency band of the acoustic signal, the vibration signal generator 40 shifts the compression control suitable band Bc by an amount based on the amount of the frequency shift.

[0078] The shift amount of the compression control suitable band Bc can also be set arbitrarily. For example, a data table correlating the frequency shift amount of the audio signal with the compression control suitable band Bc may be stored in the storage unit 42 (vibration compression data table 423), and the compression control suitable band Bc corresponding to the shift amount in the frequency shift control of the audio signal may be searched for and used from the data table.

[0079] The vibration signal generating device 40 (determination unit 433) determines whether or not to compress the vibration-corresponding band signal, or the compression method, based on the signal strength of the compression control suitable band signal. The vibration signal generating device 40 (vibration compression unit 434) compresses the vibration-corresponding band signal based on the determination result, and outputs the vibration signal generated by the compression process.

[0080] The vibration signal generated in this manner is output as a vibrator drive signal to the vibrator 50 via an amplifier 21V that performs power amplification. The vibrator 50 outputs vibrations corresponding to the vibrator drive signal to the user.

[0081] According to the above configuration, even if frequency shift processing of the audio signal is performed when there is a shortage of signals in the vibration-corresponding band Bv suitable for generating vibration in the audio signal of the content, the compression control suitable band Bc can be adjusted to generate a compression control suitable band signal suitable for control. This makes it possible to suppress the generation of a vibration signal based on an audio signal with a low volume that is not suitable for output to the user. Therefore, it is possible to more effectively output (communicate) appropriate vibrations according to the content to the user.

[0082] <4-2. Example of Operation of Content Reproducing Device in Third Embodiment> 12 is a flowchart showing a vibration signal generation process executed by the vibration signal generator 40 (controller 43) of Example 3. The operation according to this flowchart is realized by a computer program (vibration signal generation program 421) executed by the controller 43 (a computer constituting the controller 43). Note that, in the following, processing steps common to the operation flows (see FIGS. 6 and 9) described in Examples 1 and 2 are denoted by the same reference numerals, and description thereof will be omitted.

[0083] In step S101 of the process shown in FIG. 12, the controller 43 (acquisition unit 431) acquires (receives) an acoustic signal corresponding to the content to be reproduced from the content reproduction device 10, and the process proceeds to step S301.

[0084] In step S301, the controller 43 (shift unit 436) performs frequency analysis processing on the acoustic signal acquired in step S101 (acquired by the acquisition unit 431) to determine whether frequency shift processing of the acoustic signal is necessary for generating a vibration signal, and if so, proceeds to step S302, and if not, proceeds to step S303. Specifically, if the signal strength of the vibration-corresponding band signal in the acoustic signal is higher than a threshold determined in advance based on experiments or the like, it is determined that the acoustic signal contains a sufficient signal for generating a vibration signal and therefore frequency shift processing is unnecessary, and if the signal strength is lower than the threshold, it is determined that the acoustic signal does not contain enough signal for generating a vibration signal and therefore frequency shift processing is necessary.

[0085] In step S302, the controller 43 (shift unit 436) performs frequency shift processing on the acoustic signal acquired in step S101 (acquired by the acquisition unit 431) by a frequency fluctuation width determined in advance based on experiments or the like to generate a shifted acoustic signal, and then proceeds to step S303. In detail, for example, frequency shift processing is performed on the acoustic signal by a shift amount of lowering the frequency by one octave (halving the frequency).

[0086] In step S303, the controller 43 (shift unit 436) shifts the compression control suitable band Bc in accordance with the frequency shift processing (shift amount) of the audio signal. Specifically, for example, the compression control suitable band Bc is shifted by the same shift amount as the frequency shift amount of the audio signal, or by a predetermined shift amount determined in advance based on experiments, etc. For example, if frequency shift processing to lower the frequency of the audio signal by one octave (halve the frequency) is performed in step S301, frequency shift processing to lower the frequency of the compression control suitable band Bc by one octave (halve the frequency) is also performed.

[0087] In step S304, the controller 43 (vibration extraction unit 432) extracts the signal of the vibration-corresponding band Bv from the acoustic signal acquired by the acquisition unit 431 (if the judgment in step S301 is No) or the shifted acoustic signal generated in step S302 (if the judgment in step S301 is Yes) to generate a vibration-corresponding band signal, and proceeds to step S305.

[0088] In step S305, the controller 43 (vibration extraction unit 432) extracts a signal of the compression control suitable band Bc (the compression control suitable band Bc shifted in step S303 if the judgment in step S301 is Yes, or the original unshifted compression control suitable band Bc if the judgment in step S301 is No) from the shifted acoustic signal to generate a compression control suitable band signal, and proceeds to step S202.

[0089] Thereafter, in step S202, controller 43 determines whether or not to compress the vibration-corresponding band signal. If the vibration-corresponding band signal is to be compressed, in step S104 the vibration-corresponding band signal is compressed to generate a vibration signal. On the other hand, if the vibration-corresponding band signal is not to be compressed, the vibration-corresponding band signal is used as the vibration signal. Then, in step S105, the vibration signal is output to vibrator 50 as a vibrator drive signal via amplifier 21V, which performs power amplification, and the processing in FIG. 12 ends.

[0090] <5. Variations> In the real world, vibrations occur when objects move. Therefore, when sound and vibration are generated, such as when an animal walks or a car drives, the correlation between these sounds and vibrations is high, and vibrations generated from the sound are appropriate. However, the correlation between human speech and vibrations is low, and vibrations generated from sound (voice) are inappropriate. Therefore, if the compression control suitable band Bc is set to a fixed value, inappropriate control may result depending on the type of content. For example, depending on the setting of the compression control suitable band Bc, inappropriate vibrations based on human speech may be generated in television, radio, movies with a lot of dialogue, and video content with a lot of dialogue. Conversely, depending on the setting of the compression control suitable band Bc, appropriate vibrations may not be generated in content such as games with many moving objects such as automobiles and airplanes. Therefore, it is desirable to optimize this trade-off relationship.

[0091] Therefore, the vibration signal generating device 40 of the modified example adjusts the range (particularly the upper limit frequency) of the compression control suitable band Bc based on the type of content including the audio signal. In other words, television, radio, movies with a lot of dialogue, video content with a lot of dialogue, etc. are more likely to generate unwanted vibrations due to sound (human voice) than content with little dialogue, such as music, and therefore it is more important to compress the audio signal (vibration-corresponding band signal). For this reason, the upper limit frequency of the compression control suitable band Bc is set lower for these types of content than for other content with little dialogue. In other words, since the frequency components of dialogue are concentrated in the upper band of the compression control suitable band Bc, the signal strength of the compression control suitable band signal is higher for content with a lot of dialogue. As a result, the audio signal (vibration-corresponding band signal) is more easily compressed, and the generation of unwanted vibrations is suppressed.

[0092] Specifically, when acquiring (receiving) an audio signal corresponding to the content to be played from the content playback device 10, the vibration signal generator 40 acquires information related to the type of content (input source, genre, etc.) along with the audio signal as information related to the content. Then, the vibration signal generator 40 sets the upper limit frequency of the compression control suitable band Bc as follows: "videos and games with little music or conversation" > "videos, games, and radio with a lot of conversation." For example, the compression control suitable band Bc for music content is set to a frequency band from 30 Hz to 100 Hz, while the compression control suitable band Bc for content with a lot of conversation is set to a frequency band from 30 Hz to 80 Hz.

[0093] To achieve this process, for example, the vibration signal generator 40 stores the type of content and the frequency band (upper and lower limit frequencies) of the compression control suitable band Bc as a data table in the storage unit 42 (vibration compression data table 423).The vibration signal generator 40 then searches the data table based on the acquired content information (content type information) and performs a process of determining and setting the compression control suitable band Bc.

[0094] According to the above configuration, the setting of the compression control suitable band Bc can be optimized depending on the type of content. In other words, it becomes possible to output (transmit) to the user appropriate vibrations according to the content, regardless of the type of content.

[0095] <6. Points to note> Various technical features disclosed as embodiments in this specification may be modified in various ways without departing from the spirit of the technical creation. In other words, the above-described embodiments are illustrative in all respects and are not limiting. The technical scope of the present invention is defined by the claims, not by the description of the above-described embodiments, and includes all modifications that fall within the meaning and scope of the claims. Furthermore, the multiple embodiments described in this specification may be combined as appropriate to the extent possible.

[0096] In the above embodiment, various functions are realized by software through the arithmetic processing of CP1 according to a program, but at least some of these functions may be realized by electrical hardware resources. All or part of the hardware resources may be realized by, for example, an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array). Conversely, at least some of the functions realized by hardware resources may be realized by software.

[0097] It may also include a computer program that causes a processor (computer) to realize at least some of the functions of the content reproduction system 1 (vibration signal generating device 40). Note that such a computer program can be stored in a computer-readable nonvolatile recording medium (for example, the above-mentioned nonvolatile memory, as well as an optical recording medium (for example, an optical disk), a magneto-optical recording medium (for example, a magneto-optical disk), a USB memory, or an SD card) and provided (sold, etc.), and can also be provided from a server device via a communication line such as the Internet, i.e., by downloading. [Explanation of symbols]

[0098] 1 Content playback system 10 Content playback device 20 Surround Sound Equipment 30 speakers 40 Vibration signal generation device 41 Communications Department 42 Storage section 43 Controller 50 oscillators 421 Vibration Signal Generator 422 Vibration Control Data Table 423 Vibration Compression Data Table 431 Acquisition Department 432 Vibration extraction part 433 Judgment section 434 Vibration Compression Section 435 Output Section 436 Shifter Se sheet V1 vehicle

Claims

1. A vibration signal generating device that generates a vibration signal based on an audio signal corresponding to content, extracting a signal of a vibration-corresponding band corresponding to the vibration to be output to the user from the acoustic signal to generate a vibration-corresponding band signal; extracting a signal of a predetermined compression control suitable band from the acoustic signal to generate a compression control suitable band signal; compressing the vibration-corresponding band signal according to the signal intensity of the compression control preferred band signal to generate the vibration signal; Vibration signal generator.

2. The compression control preferred band is the vibration corresponding band, The vibration signal generating device according to claim 1 .

3. The compression control preferred band is a frequency band lower than the vibration corresponding band. The vibration signal generating device according to claim 1 .

4. If the signal intensity of the vibration-corresponding band signal is lower than a predetermined shift determination threshold, the vibration-corresponding band signal is frequency-shifted; The vibration signal generating device according to claim 1 .

5. The compression control preferred band is changed according to the frequency shift of the vibration-corresponding band signal. The vibration signal generating device according to claim 4 .

6. The compression control preferred band is frequency-shifted by the same amount as the frequency shift of the vibration-corresponding band signal. The vibration signal generating device according to claim 5 .

7. If the signal strength of the compression control suitable band signal is greater than a predetermined compression possibility determination threshold, the compression is not performed. The vibration signal generating device according to claim 1 .

8. adjusting the frequency band of the compression control suitable band based on the type of the content; The vibration signal generating device according to claim 1 .

9. A content playback system that outputs sound and vibration according to content to a user, A content playback device, a speaker device, a vibration device, and a vibration signal generation device are provided, the content playback device outputs an audio signal corresponding to the content; the speaker device outputs a sound based on the acoustic signal; the vibration device outputs vibrations according to the vibration signal output by the vibration signal generation device, The vibration signal generating device is extracting a signal of a vibration-corresponding band corresponding to the vibration to be output to the user from the acoustic signal to generate a vibration-corresponding band signal; extracting a signal of a predetermined compression control suitable band from the acoustic signal to generate a compression control suitable band signal; compressing the vibration-corresponding band signal according to the signal intensity of the compression control preferred band signal to generate the vibration signal; Content playback system.

10. A vibration signal generating program for generating a vibration signal based on an audio signal corresponding to a content, extracting a signal of a vibration-corresponding band corresponding to the vibration to be output to the user from the acoustic signal to generate a vibration-corresponding band signal; extracting a signal of a predetermined compression control suitable band from the acoustic signal to generate a compression control suitable band signal; causing a computer to perform a process of compressing the vibration-corresponding band signal in accordance with the signal intensity of the compression control suitable band signal to generate the vibration signal; Vibration signal generator.

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