JP2020014138A - Sound signal processing device - Google Patents

Abstract

To allow a user to easily use the sound effect that emphasizes a dialogue and the sound effect that emphasizes the spread of a sound image.SOLUTION: In a sound signal processing device 100, a dialogue emphasis processing unit 101 generates a first sound signal in which a first sound effect that emphasizes a dialogue is added to an input sound signal. A surround processing unit 102 generates a second sound signal in which a second sound effect that emphasize the spread of a sound image is added to the input acoustic signal. The strengths of the first sound effect and the second sound effect are collectively set by a sound effect set value set by a user, and a sound effect control unit 104 outputs the weighted sum of the input sound signal and the first sound signal and the weighted sum of the input sound signal and the second sound signal on the basis of the sound effect set value.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an audio signal processing device for giving an audio effect to an audio signal.

  Many audio devices, such as televisions and car navigation systems (car navigation systems), include an audio signal processing device that allows a user (listener) to adjust the sound quality of output sound. For example, in television programs such as news and dramas, there is a need for a sound effect that emphasizes the easiness of hearing a human voice (hereinafter, collectively referred to as “line”) such as a line or an announcement, that is, a sound effect that emphasizes the line. . On the other hand, for sound effects of music and movies, there is a need for an acoustic effect that emphasizes the spread of a sound image, that is, an acoustic effect that emphasizes the spread of a sound image. In general, output sound mainly composed of human voice tends to be generated such that a sound image is localized at the center between speakers placed on the left and right, and output sound of music and movie sound effects is generated only at the center. However, there is a strong tendency that the sound image is generated so that the sound image is localized in the right and left directions.

  Also, algorithms for acoustic signal processing for obtaining various acoustic effects have been developed and implemented in audio equipment. For example, in Japanese Patent Application Laid-Open No. 2003-216, the speech is emphasized by applying a filter that extracts a vocal audio band and a notch filter that attenuates a specific frequency component from the vocal audio band to the sum signal of the left and right channels of the stereo signal. A technique for obtaining the following acoustic effect is disclosed. Further, Patent Document 2 discloses that a front stereo signal and a rear surround signal are reproduced by using a pair of speakers arranged in front of the user, and the sound image of the rear surround sound is localized behind the user, thereby expanding the sound image. There is disclosed a technique for obtaining a sound effect that emphasizes the sound.

JP 2005-086462 A JP-A-8-265899

  A general audio device often has both a function of obtaining a sound effect that emphasizes dialogue and a function of obtaining a sound effect that emphasizes spread of a sound image, and both can be operated simultaneously. However, when the function of obtaining the sound effect that emphasizes the dialogue and the function of obtaining the sound effect that emphasizes the spread of the sound image are simultaneously operated, the effects are mutually weakened, and it is difficult for the user to use the two sound effects properly. .

  SUMMARY An advantage of some aspects of the invention is to provide a sound signal processing method that enables a user to easily use a sound effect that emphasizes dialogue and a sound effect that emphasizes the spread of a sound image. It is intended to provide a device.

  An audio signal processing device according to the present invention includes a speech enhancement processing unit that generates a first audio signal to which a first acoustic effect that enhances speech is applied to an input audio signal, and a sound image for the input audio signal. A surround processing unit that generates a second sound signal to which a second sound effect that emphasizes the spread of the sound is added, and a unit that collectively sets the strength of the first sound effect and the second sound effect. A user setting acquisition unit that acquires a setting value of a sound effect setting value by a user, and, based on the sound effect setting value, a weighted sum of the input sound signal and the first sound signal, or an input sound signal. And a sound effect control unit that outputs a weighted sum with the second sound signal.

  ADVANTAGE OF THE INVENTION According to the acoustic signal processing apparatus which concerns on this invention, the intensity | strength of the acoustic effect (first acoustic effect) which emphasizes a dialogue, and the acoustic effect (second acoustic effect) which emphasizes the spread of a sound image is set to one acoustic effect. Since the settings can be collectively set using the set values, the user can easily use the two sound effects properly.

1 is a diagram illustrating a configuration of an audio signal processing device according to an embodiment of the present invention. It is a figure showing an example of a GUI screen of an acoustic signal processing device concerning an embodiment of the invention. 4 is a flowchart illustrating an operation of the audio signal processing device according to the embodiment of the present invention. 1 is a diagram illustrating a configuration example of an audio system using an audio signal processing device according to an embodiment of the present invention. 1 is a diagram illustrating a configuration example of an audio system using an audio signal processing device according to an embodiment of the present invention.

  FIG. 1 is a diagram showing a configuration of an audio signal processing device 100 according to an embodiment of the present invention. As shown in FIG. 1, the audio signal processing device 100 includes a speech enhancement processing unit 101, a surround processing unit 102, a user setting acquisition unit 103, and a sound effect control unit 104. Further, a display device 105 and an operation input device 106 are connected to the acoustic signal processing device 100. Here, it is assumed that the audio signal (input audio signal) input to the audio signal processing apparatus 100 is a 5.1-channel signal or a 2-channel stereo signal. In the following, processing for the two types of input audio signals will be described. I will mainly explain. However, the input sound signal is not limited to the two types, and may be, for example, a 7.1ch signal. Also, here, it is assumed that the present invention is applied to audio equipment that outputs stereo sound, such as a general liquid crystal television, and that the audio signal (output audio signal) output from the audio signal processing device 100 is a stereo signal. However, the output audio signal is not limited to a stereo signal, and, for example, the audio signal processing device 100 may output an output audio signal having the same number of channels as the input audio signal.

  The serif emphasis processing unit 101 performs a serif emphasis process for giving a sound effect (first sound effect) for emphasizing serifs to an input audio signal, and performs an audio signal (first sound effect) to which a sound effect for emphasizing serifs is applied. Is output.

  When the input audio signal is a stereo signal, the dialog emphasis processing unit 101 performs a process of extracting and emphasizing a correlation component between the left channel (Lch) signal and the right channel (Rch) signal, thereby giving a dialog to the input audio signal. The sound effect which emphasizes is given. The method of extracting the correlation component of the stereo signal may be a general method, and for example, a method disclosed in Patent Document 1 can be used.

  When the input audio signal is a 5.1ch signal, the dialog emphasis processing unit 101 uses the following expression (for example, using the front left channel signal, the center channel (Cch) signal, and the front right channel signal included in the 5.1ch signal) On the basis of 1), a left channel signal and a right channel signal of a stereo signal to which a sound effect that emphasizes dialogue is added are generated.

In equation (1), x _fl (n) is a front left channel signal, x _fr (n) is a front right channel signal, and x _c (n) is a center channel signal. Further, y ′ _l (n) is a left channel signal of a stereo signal to which a sound effect that emphasizes dialogue is added, and y ′ _r (n) is a right channel of a stereo signal to which a sound effect that emphasizes dialogue is added. Signal. Here, n is the index of the sample.

  The method by which the line emphasis processing unit 101 imparts a sound effect that emphasizes lines to the input audio signal is not limited to the above method, and may be any method.

  The surround processing unit 102 performs a surround process for providing an acoustic effect (second acoustic effect) for enhancing the spread of the sound image to the input acoustic signal, and performs an acoustic signal ( (A second acoustic signal).

  When the input audio signal is a stereo signal, the surround processing unit 102 uses a characteristic that a sound image is expanded as the distance between a pair of speakers that output stereo sound is wider, and the surround processing unit 102 uses, for example, a transaural system that is a known algorithm. The transmission characteristics of a virtual pair of speakers arranged at a wider interval than a pair of speakers (not shown in FIG. 1) connected to the audio signal processing apparatus 100 are added to the input audio signal.

  When the input sound signal is a 5.1ch signal, the surround processing unit 102 uses the front left channel signal, the front right channel signal, the center channel signal, the rear left channel signal, and the rear right channel signal of the 5.1ch signal to perform input. By performing a process of giving a sound effect that emphasizes the spread of the sound image to the acoustic signal, a left channel signal and a right channel signal of a stereo signal to which the sound effect that emphasizes the spread of the sound image is added may be generated. The method of enhancing the spread of the sound image may be a general method, and for example, a method disclosed in Patent Document 2 can be used.

  The method by which the surround processing unit 102 imparts an acoustic effect that emphasizes the spread of the sound image to the input audio signal is not limited to the above method, and may be any method.

  Here, in the acoustic signal processing device 100 according to the present embodiment, the strength of the sound effect that emphasizes the words given to the input sound signal and the strength of the sound effect that emphasizes the spread of the sound image are individually set. Instead, they are collectively set by one (one-dimensional) sound effect setting value. The sound effect set value is set according to the user's preference.

  In the present embodiment, the user setting acquisition unit 103 causes the display device 105 to display a GUI (Graphical User Interface) screen 200 as shown in FIG. 2, and the user operates the GUI screen 200 using the operation input device 106. , A sound effect set value can be set.

  Here, the display device 105 is, for example, a liquid crystal display device. The operation input device 106 is used to operate the GUI screen 200 displayed on the display device 105, and is, for example, a keyboard, an operation lever, a mouse, a touch pad, or the like. A touch pad as the operation input device 106 may be provided on the screen of the display device 105, and the display device 105 and the operation input device 106 may be configured as one touch panel.

  The GUI screen 200 of FIG. 2 includes a slide bar 201. When the user moves the slider 201a closer to the left end of the slide bar 201, the sound effect that emphasizes the dialogue becomes stronger, and when the user moves closer to the right end of the slide bar 201, the sound image spreads. The sound effect setting value is set so that the sound effect that emphasizes is enhanced. Also, when the slider 201a is positioned at the center of the slide bar 201, the input audio signal is not provided with an acoustic effect that emphasizes dialogue or an acoustic effect that enhances the spread of the sound image.

  The user setting acquisition unit 103 acquires the sound effect set value set by the user by converting the position of the slider 201a on the slide bar 201 into a sound effect set value. In the present embodiment, the sound effect set value is set to 0 when the slider 201a is located at the left end of the slide bar 201, and the sound effect set value is set to 50 when the slider 201a is located at the center of the slide bar 201. When the slider 201a is located at the right end of the slide bar 201, the sound effect set value is set to 100.

  Note that the configuration of the GUI screen is not limited to the example shown in FIG. For example, a coordinate input plane on which a user can input coordinates using a slider may be provided on the GUI screen, and the sound effect setting value may be set according to the coordinates of the slider. That is, the strength of one of the sound effect that emphasizes the dialogue and the sound effect that emphasizes the spread of the sound image changes in accordance with the X coordinate (horizontal coordinate) of the slider, and changes to the Y coordinate (vertical coordinate) of the slider. The strength of the other may be changed accordingly. For example, it is conceivable to set the sound effect set value based on the difference or ratio between the X coordinate and the Y coordinate of the position of the slider.

  In addition, the GUI screen may include a display of the sound effect set value set by the user.

  Based on the sound effect setting value obtained by the user setting obtaining unit 103, the sound effect control unit 104 generates the input sound signal and the sound signal generated by the dialog emphasis processing unit 101 (the sound signal to which the sound effect for emphasizing the dialogue is added). ), Or the weighted sum of the input audio signal and the audio signal generated by the surround processing unit 102 (the audio signal to which the sound effect that emphasizes the spread of the sound image is added) is calculated as the final output. Generated as an acoustic signal (output acoustic signal).

  When the input audio signal is a stereo signal, the sound effect control unit 104 obtains a left channel signal and a right channel signal of the output audio signal using the following equations (2) and (3).

In the equation (2), x _l (n) is a left channel signal of the input audio signal, y ′ _l (n) is a left channel signal to which a sound effect for emphasizing the speech is given by the speech enhancement processing unit 101, y ″ _{l (n)} is the left channel signal sound effect emphasizing the spread of sound image is provided by a surround processor 102, y l _(n) is a left channel signal of the output acoustic signal. In Expression (3), x _r (n) is a right channel signal of the input audio signal, y ′ _r (n) is a right channel signal to which a sound effect for emphasizing the words is added by the word emphasis processing unit 101, y ″ _{r (n)} is the right channel signal sound effect emphasizing the spread of sound image is provided by a surround processor 102, y r _(n) is a right channel signal of the output acoustic signal. Α is a weighting coefficient determined based on the sound effect set value β (0 ≦ β ≦ 100) set by the user, and is obtained by the following equation (4).

  When the input audio signal is a 5.1ch signal, the sound effect control unit 104 obtains a left channel signal and a right channel signal of the output audio signal using the following equations (5) and (6).

In Expression (5), x _fl (n) is a front left channel signal of the input audio signal, y ′ _l (n) is a left channel signal to which a sound effect for enhancing the speech generated by the speech enhancement processing unit 101 is added, y ″ _l (n) is a left channel signal to which a sound effect for enhancing the spread of the sound image generated by the surround processing unit 102 is added, and y _l (n) is a left channel signal of the output sound signal. In the equation (6), x _fr (n) is a front right channel signal of the input audio signal, y ′ _r (n) is a right channel signal to which a sound effect for enhancing the speech generated by the speech enhancement processing unit 101 is added, y ″ _r (n) is a right channel signal to which a sound effect for enhancing the spread of the sound image generated by the surround processing unit 102 is added, and y _r (n) is a right channel signal of the output sound signal. Α is a weighting coefficient determined based on the sound effect set value β (0 ≦ β ≦ 100) set by the user, and is obtained by the above equation (4).

  As can be seen from Expressions (2) to (6), when the sound effect set value is less than 50, the sound effect control unit 104 of the present embodiment has applied the sound effect that emphasizes the input sound signal and the words. The weighted sum with the sound signal is output as an output sound signal. When the sound effect set value is 50, the input sound signal is output as it is as the output sound signal. When the sound effect set value is larger than 50, the input sound is output. A weighted sum of the signal and an acoustic signal to which an acoustic effect for enhancing the spread of the sound image is added is output as an output acoustic signal. Also, the smaller the sound effect set value, the stronger the sound effect that emphasizes the dialogue, and the larger the sound effect set value, the stronger the sound effect that emphasizes the spread of the sound image.

  Therefore, by setting the sound effect setting value, the user can collectively set the strength of the sound effect that emphasizes the words and the sound effect that emphasizes the spread of the sound image. Therefore, the user can intuitively and easily use these two sound effects properly without being conscious of switching between the sound effect that emphasizes the dialogue and the sound effect that emphasizes the spread of the sound image.

  FIG. 3 is a flowchart showing the operation of the acoustic signal processing device 100. Hereinafter, the operation of the acoustic signal processing device 100 will be described with reference to FIG.

  When an input audio signal is input to the audio signal processing device 100, the speech enhancement processing unit 101 generates an audio signal in which an acoustic effect for enhancing speech is added to the input audio signal (step S10). Further, the surround processing unit 102 generates an audio signal in which an acoustic effect for enhancing the spread of the sound image is added to the input audio signal (step S11).

  Next, the user setting acquisition unit 103 acquires a sound effect set value set by the user based on the position of the slider 201a of the slide bar 201 on the GUI screen 200 (Step S12). In the present embodiment, the sound effect set value β is a real number satisfying 0 ≦ β ≦ 100.

  Subsequently, the sound effect control unit 104 checks the sound effect set value acquired by the user setting acquisition unit 103. If the sound effect set value is less than 50 (NO in step S13), the sound effect control unit 104 sets the weighted sum of the input sound signal and the sound signal to which the sound effect for enhancing the dialogue is added as the output sound signal. Generate and output (step S14). If the sound effect set value is larger than 50 (NO in step S15), the sound effect control unit 104 outputs the weighted sum of the input sound signal and the sound signal to which the sound effect for enhancing the spread of the sound image is added as the output sound signal. Is generated and output (step S16). If the sound effect set value is 50 (YES in step S15), the sound effect control unit 104 outputs the input sound signal as it is as an output sound signal (step S17).

  3 is repeatedly executed by the acoustic signal processing device 100.

  The acoustic signal processing device 100 can be realized by hardware or software.

  FIG. 4 is a block diagram illustrating a configuration example of an audio system using the audio signal processing device 100 configured by hardware. The audio system in FIG. 4 includes a processing circuit 301, a media playback device 302, a broadcast wave receiving device 303, a DAC (Digital to Analog Converter) circuit 304, an amplifier 305, a speaker 306, a display device 307, and an operation input device 308. I have.

  The processing circuit 301 is a circuit having the function of the audio signal processing device 100. That is, the processing circuit 301 generates a first sound signal to which a first sound effect that emphasizes speech is added to the input sound signal, and generates a second sound that emphasizes the spread of the sound image with respect to the input sound signal. Generating a second sound signal to which an effect is applied, acquiring a user-set value of a sound effect set value for collectively setting the intensity of the first sound effect and the second sound effect; A circuit that outputs a weighted sum of an input audio signal and a first audio signal or a weighted sum of an input audio signal and a second audio signal based on a set value. The processing circuit 301 includes, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a combination thereof. Applicable.

  The media playback device 302 reads a digital signal to be an input audio signal from a medium such as a CD (Compact Disc), a DVD (Digital Versatile Disc), or a BD (Blu-ray Disc (registered trademark)), and processes the signal. Enter The broadcast wave receiving device 303 is a television, a radio, or the like that receives a broadcast wave, and inputs a digital signal serving as an input audio signal to the processing circuit 301.

  The DAC circuit 304 converts an output audio signal output from the processing circuit 301 as the audio signal processing device 100 into an analog signal. The output audio signal converted to an analog signal is amplified by the amplifier 305 and output from the speaker 306 as sound.

  The display device 307 and the operation input device 308 correspond to the display device 105 and the operation input device 106 shown in FIG.

  FIG. 5 is a block diagram illustrating a configuration example of an audio system using the acoustic signal processing device 100 configured by software. The audio system in FIG. 5 includes an external storage device 401, a memory 402, a processor 403, a media playback device 404, a broadcast wave reception device 405, a speaker 406, a display device 407, and an operation input device 408.

  The acoustic signal processing device 100 is realized by the processor 403 reading out a program stored in the external storage device 401 to the memory 402 and executing the program stored in the memory 402. That is, when the program is executed by the processor 403, a process of generating a first sound signal to which a first sound effect that emphasizes dialogue is added to the input sound signal, A process of generating a second acoustic signal to which a second acoustic effect for enhancing the spread of a sound image is provided, and an acoustic effect setting for collectively setting the intensity of the first acoustic effect and the second acoustic effect A process of acquiring a value set by a user and a weighted sum of an input audio signal and a first audio signal, or a weighting of an input audio signal and a second audio signal based on a sound effect set value And a program for outputting the sum.

  Note that the external storage device 401 is, for example, a hard disk drive (HDD) or a solid state drive (SSD) connected to the processor 403 directly or via a network.

  The media reproducing device 404 and the broadcast wave receiving device 405 correspond to the media reproducing device 302 and the broadcast wave receiving device 303 shown in FIG. 4, and transmit a digital signal to be an input audio signal to the processor 403.

  The speaker 406 is a digital input speaker, and outputs a sound based on an output audio signal of a digital signal generated by the processor 403 as the audio signal processing device 100. Of course, a DAC circuit and an analog input speaker may be used instead of the speaker 406.

  The display device 407 and the operation input device 408 correspond to the display device 105 and the operation input device 106 shown in FIG.

  In the present invention, the embodiments can be appropriately modified and omitted within the scope of the invention.

  Reference Signs List 100 acoustic signal processing device, 101 serif emphasis processing unit, 102 surround processing unit, 103 user setting acquisition unit, 104 sound effect control unit, 105 display device, 106 operation input device, 200 GUI screen, 201 slide bar, 201a slider, 301 Processing circuit, 302 media playback device, 303 broadcast wave reception device, 304 DAC circuit, 305 amplifier, 306 speaker, 307 display device, 308 operation input device, 401 external storage device, 402 memory, 403 processor, 404 media playback device, 405 Broadcast wave receiving device, 406 speaker, 407 display device, 408 operation input device.

Claims (4)

A speech enhancement processing unit that generates a first audio signal to which a first acoustic effect that enhances speech is added to an input audio signal;
A surround processing unit that generates a second sound signal to which a second sound effect that emphasizes the spread of a sound image is added to the input sound signal;
A user setting acquisition unit that acquires a user-set value of a sound effect set value for setting the strengths of the first sound effect and the second sound effect collectively;
A sound effect control unit that outputs a weighted sum of the input sound signal and the first sound signal or a weighted sum of the input sound signal and the second sound signal based on the sound effect set value. When,
An audio signal processing device comprising: The sound effect set value is input by the user using a GUI screen displayed on a display device,
In the GUI screen, the sound effect setting value is set such that the first sound effect is enhanced when the slider is moved closer to one end, and the second sound effect is increased when the slider is moved closer to the other end. Equipped with a slide bar,
The acoustic signal processing device according to claim 1. The sound effect set value is input by the user using a GUI screen displayed on a display device,
In the GUI screen, the intensity of one of the first sound effect and the second sound effect changes according to a horizontal coordinate of a slider, and the first sound effect changes according to a vertical coordinate of the slider. A coordinate input plane on which the sound effect setting value is set such that the strength of the other of the sound effect and the second sound effect changes.
The acoustic signal processing device according to claim 1. The acoustic signal processing device according to claim 2, wherein the GUI screen includes a display of the acoustic effect set value set by a user.

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