JP2013157960A - Information processing device and method for processing acoustic signal of the same - Google Patents

Abstract

An information processing apparatus and an acoustic signal processing method capable of correcting the characteristics of an earphone with low-cost and simple work are provided.
Measurement means for measuring frequency characteristics of an earphone connected to the output terminal from a measurement audio signal output from an output terminal for outputting an audio signal and picked up by a microphone, and the measurement means Based on the frequency characteristics of the earphones measured by the above and a predetermined target frequency characteristic, a high frequency range higher than the crossover band, which is a frequency band for switching from a low frequency range to a high frequency range, or a low frequency lower than the crossover frequency band Correction filter design means for designing a correction filter for correcting the frequency characteristic of the sound output from the earphone to the predetermined target frequency characteristic for one of the sound ranges, and the high frequency based on an external designation An information processing apparatus comprising: adjusting means for adjusting a volume balance between a sound range and the low sound range.
[Selection] Figure 4

Description

Embodiments described herein relate generally to an acoustic signal processing technique suitable for an information processing apparatus having an output terminal to which an earphone can be connected.

2. Description of the Related Art In recent years, information processing apparatuses that can be driven by a battery and that are called notebook PCs (Personal computers) are widely used. Some of these types of information processing devices are capable of outputting high-definition images and high-quality sound, such as advanced AV (Audio and visual) equivalent to stationary information processing devices. ) There are many things with functions. Such high-function model notebook PCs are often used as DVD (Digital versatile disc) players and music players.

Such a high-performance model notebook PC includes an output terminal for outputting an audio signal to which an earphone can be connected together with a speaker. For example, in an environment where sound cannot be output from a speaker, the user connects an earphone to the output terminal and
Watch the audio played by C.

Each unspecified number of earphones that can be used by a user has characteristics. For this reason, various mechanisms for appropriately correcting the characteristics of an unspecified number of earphones have been proposed.

JP 2010-226329 A

However, the mechanism for correcting the characteristics of the earphones proposed so far has problems such as an increase in cost and a complicated work for the user.
It is an object of the present invention to provide an information processing apparatus and an acoustic signal processing method for the same that can correct the characteristics of the earphones with low cost and simple work.

In order to solve the above-mentioned problem, according to the embodiment, an information processing apparatus includes an output terminal for outputting an audio signal, a microphone, and a measurement sound output from the output terminal and collected by the microphone. A measurement unit that measures a frequency characteristic of an earphone connected to the output terminal from a signal, a frequency characteristic of the earphone that is measured by the measurement unit, and a predetermined target frequency characteristic, from a low range to a high range The frequency characteristic of the sound output from the earphone is set to the predetermined target frequency characteristic for one of the high range higher than the crossover band that is the frequency band to be switched to or the lower range lower than the crossover band. Based on correction filter design means to design correction filter for correction and designation from outside Wherein the serial high frequency range, characterized by comprising an adjustment means for adjusting the volume balance between the low frequency range.

  The effect of the invention is not particularly described.

1 is a diagram illustrating an appearance of an information processing apparatus according to an embodiment. The figure which shows the system configuration | structure of the information processing apparatus of embodiment. 2 is an exemplary diagram showing functional blocks of a media player operating on the information processing apparatus according to the embodiment. FIG. The figure which shows the case where an equalizer is designed only in the high region (right side from the dotted line in a figure) of embodiment. The figure which shows the frequency characteristic of the earphone measured in the state shown in FIG. The figure which shows the state which suppressed the high region side of embodiment and reduced auditory annoyance. The figure which shows the case where an equalizer is designed only in the high region (right side from the dotted line in a figure) of embodiment. The figure which shows the frequency characteristic of the earphone measured in the state shown in FIG. The figure which shows the state which suppressed the high region side of embodiment and reduced auditory annoyance. The figure for demonstrating the effect which the information processing apparatus of embodiment makes it the shape which the whole increase / decrease amount changes with the increase / decrease in the value of the slider bar SB. The figure for demonstrating one application example of the acoustic signal process performed in order that the information processing apparatus of embodiment may correct | amend the frequency characteristic of an earphone. The flowchart which shows the flow of the acoustic signal process performed in order that the information processing apparatus of embodiment may correct | amend the frequency characteristic of an earphone.

Hereinafter, an embodiment of the present invention will be described.
(First embodiment)
A first embodiment will be described with reference to FIGS. 1 to 6 and FIGS. 11 to 12.
FIG. 1 is a diagram illustrating an external appearance of the information processing apparatus according to the present embodiment when the display unit is opened. This information processing apparatus is realized as, for example, a notebook-type PC 1 that can be driven by a battery and has portability.

As shown in FIG. 1, the PC 1 includes a computer main body 11 and a display unit 12. The display unit 12 includes an LCD (Liquid crystal display).
) 13 is incorporated. The display unit 12 is attached to the computer main body 11 so as to be rotatable between an open position where the upper surface of the computer main body 11 is exposed and a closed position covering the upper surface of the computer main body 11.

The computer main body 11 has a thin box-shaped housing, and a keyboard 1 is provided on the upper surface thereof.
4 and a touch pad 15 are arranged. The computer main body 11 has a built-in microphone, and a microphone hole is provided in the front portion of the housing so that the microphone can efficiently collect sound. Further, an output terminal for outputting an audio signal to which the earphone 16 can be connected is provided on the side surface of the casing of the computer main body 11.

When the measurement audio signal is output to the output terminal (to which the earphone 16 is connected) with the earphone 16 in contact with the microphone hole, the measurement audio signal is picked up by the microphone. Characteristics can be measured. The information processing apparatus (PC1) of the present embodiment includes a mechanism for correcting the characteristics of the earphone 16 that can be measured in this way with a low-cost and simple operation. This point will be described in detail below. .

FIG. 2 is a diagram illustrating a system configuration of the PC 1.
As shown in FIG. 2, the PC 1 includes a CPU (Central processing unit) 101, a North Bridge 102, a main memory 103, a South Bridge 104, a GPU (Graphics processing).
unit) 105. The PC 1 also has a sound controller 106, a BIOS (
Basic input / output system)-ROM (Read only memory) 107, LAN (Local are
a network) controller 108, HDD (Hard disk drive) 109, ODD (Optical
disc drive) 110 and EC / KBC (Embedded controller / Keyboard controller)
111.

The CPU 101 is a processor that controls the operation of the PC 1 and executes various programs loaded from the HDD 109 to the main memory 103. Among various programs executed by the CPU 101, an OS (Operating System) 121 that manages resource management and the O
There is an application such as a media player 122, which will be described later, that operates under S121. The media player 122 is application software for reproducing moving image (video) and audio files. The CPU 101 also executes the BIOS stored in the BIOS-ROM 107. The BIOS is a program for hardware control.

The north bridge 102 operates as a bridge device that connects between the CPU 101 and the south bridge 104 and also operates as a memory controller that controls access to the main memory 103. The north bridge 102 has a function of executing communication with the GPU 105.

The GPU 105 is a display controller that performs image display on the LCD 13 incorporated in the display unit 12. Further, the GPU 105 includes an accelerator that draws an image to be displayed by various programs in place of the CPU 101.

The south bridge 104 operates as a memory controller that controls access to the BIOS-ROM 107. The south bridge 104 includes an HDD 109 and an ODD 110.
It incorporates an IDE (Integrated Device Electronics) controller for controlling. Further, the south bridge 104 has a function of executing communication with the sound controller 106.

The sound controller 106 is a sound source device, and converts a digital signal into an electrical signal in order to output audio data to be reproduced to a speaker 112 or an output terminal 113 (provided on the side surface of the casing of the computer main body 11). Circuits such as a D / A converter that performs amplification and an amplifier that amplifies an electric signal. Sound controller 1
06 includes a circuit such as an A / D converter that converts an electric signal input from the microphone 114 (built in the computer main body 11 described above) into a digital signal.

The EC / KBC 111 includes an embedded controller for performing power management of the PC 1,
A one-chip microcomputer in which a keyboard controller and a keyboard controller for controlling the touch pad 15 are integrated.

FIG. 3 is a diagram showing functional blocks of the media player 122 operating on the PC 1 having the system configuration as described above.
As shown in FIG. 3, the media player 122 includes a signal measurement unit 210, a correction / playback unit 2.
20. The signal measurement unit 210 includes a measurement unit 211 and a correction filter design unit 2.
12 and the target characteristic generation unit 213, and the correction / reproduction unit 220 includes a correction filter 221 and an acoustic signal reproduction unit 222.

Here, in order to help understand the main contents of the present application, first, the relationship between Japanese Patent Application 2011-166782 by the same inventors as the present application and the present application will be described. This prior application provides the measurement of the earphone characteristics necessary for correcting the acoustic characteristics of the earphones with an equalizer in a form that can be measured by the user and at a low cost.

That is, insert the earphone into the headphone terminal of the device, and output the measurement signal from here,
It is a method for collecting the measurement signal using a microphone mounted on the device and calculating the characteristics of the earphone from the collected signal, and by limiting the correction frequency, only the contact measurement, or The earphone frequency characteristic of the target band is obtained by one measurement of only one of the open measurements, and correction is performed.

However, in this method, in open measurement, an equalizer that corrects only the high frequency is designed based on the measurement of only the high frequency, so even if the equalizer is designed so that the volume does not change within the design band (high frequency). There is a problem that the balance between the low and high frequencies may be lost. Therefore, after designing the equalizer, a function was provided to adjust the balance between the low and high frequencies, allowing the user to adjust the balance according to their preferences as follows.

<Example 1: Correction for lowering high range>
In the embodiment of FIG. 1, the earphone 16 is inserted into a headphone output terminal (not shown) of the device (computer main body 11), a measurement signal is sent from the headphone output terminal, and this signal is collected by a microphone. Measure the characteristics of the earphones. Examples of measurement signals include white noise, pink noise, and TSP signals. A frequency characteristic (measurement characteristic) is obtained from the measurement signal acquired by the microphone.

FIG. 4 shows measurement characteristics, target characteristics, and equalizer characteristics with the horizontal axis representing frequency and the vertical axis representing amplitude. The target characteristic is an ideal frequency characteristic of an earphone mounted in advance on the device. The equalizer is designed to match the measurement characteristics to the target characteristics. By applying the designed equalizer to the signal to be reproduced, it is possible to obtain sound quality such as target characteristics with the user's earphone used for measurement.

By the way, as in the previous application, when the frequency domain where the equalizer is designed is limited,
The volume balance between the low and high ranges may be lost. FIG. 4 shows a case where the equalizer is designed only in the high region (right side from the dotted line in the figure). In this case, the equalizer characteristic is flat (gain 0) in the low range and is not corrected, and has a shape that brings the measurement characteristic close to the target characteristic in the high range. As a result, the frequency characteristic of the earphone to which the designed equalizer is applied is as shown in FIG. For the high frequency, the target characteristics and the shape are the same, and the sound is as designed. However, for the low frequency, the correction amount is zero, and the characteristics of the original user earphone remain. Although it is a reasonable result under the condition that the band is limited, there may be a case where a high tone is heard audibly. As the cause, there is a problem that the balance of the volume of the low range and the high range is broken. In the target characteristic of FIG.
A is higher at the level near A and the level near high band B. On the other hand, the high region B is higher in FIG. This is because only B has been lifted where correction should be made while maintaining the balance between A and B. Since A is outside the target band, it is difficult to consider in the correction that limits the band.

Therefore, after designing the equalizer, a filter that controls the high frequency by the user's operation is added, and a function that adjusts based on the auditory impression is added. For example, the application described in FIG. 2 is provided with a display means on the LCD 13 for a slider bar (with scale value display), and a mechanism that allows the user to adjust while listening to the sound after designing the equalizer is configured. The shape of the filter that controls the high range is experimentally determined, but a filter whose gain increases or decreases as the frequency increases is prepared, and the overall increase / decrease amount changes as the value of the slider bar SB increases / decreases. The shape is effective (see FIG. 10).

In order to prevent the shape outside the target band from changing, it is also effective to set the frequency range in which the gain is increased or decreased only to the target band. Furthermore, when the target band is a high band, it is also effective to increase / decrease only the band of 2 kHz or higher where the annoyance starts to be a concern. In addition to the slider bar, dials and numerical input, or other buttons such as normal, high, low and three-level push buttons
You can use UI. By adopting such a configuration, it becomes possible to suppress the high frequency side as shown by the white arrow in FIG. In addition, there is an advantage that the equalizer design error due to variations in microphone characteristics for each product can be corrected to some extent by the user.

FIG. 11 is a diagram for explaining an application example of acoustic signal processing executed by the PC 1 of the present embodiment to correct the frequency characteristics of the earphone.
Here, even when a device such as a portable audio player (sound reproduction device 2) that is difficult to include an arbitrary correction filter is used, when the user views music using the earphone 16, the above-described correction is performed. An example for achieving the effect will be described.

In this case, the correction / playback unit 220 of the media player 122 shown in FIG.
The playback unit 220B is divided into 0A and the playback unit 220B, and the playback unit 220B is disposed on the side of the sound playback device 2 that is externally connected to the PC 1.

In the example described above, the sound reproduced by the acoustic signal reproduction unit 222 is corrected using the correction filter 221 (to which the coefficient created by the correction filter design unit 212 of the signal measurement unit 210 is applied), and after the correction. The audio signal was output from the output terminal 113. On the other hand, in the application example shown in FIG. 11, the audio signal corrected using the correction filter 221 is supplied to the corrected acoustic data generation unit 223. The corrected acoustic data generation unit 223 encodes the supplied audio signal to generate corrected acoustic data, and stores the generated corrected acoustic data in the acoustic data storage unit 224 of the sound reproduction device 2. And the reproduction | regeneration processing part 225 of the reproduction | regeneration part 220B arrange | positioned at the sound reproduction apparatus 2 reproduce | regenerates the correction | amendment acoustic data stored in the acoustic data memory | storage part 224, and outputs it from an output terminal.

That is, by transferring the corrected data to the reproduction unit 220B, it is possible to obtain the correction effect during reproduction even in a device (sound reproduction apparatus 2) that cannot perform arbitrary correction.

FIG. 12 is a flowchart showing the flow of acoustic signal processing executed by the PC 1 to correct the earphone frequency characteristics.
Here, it is assumed that the main correction target is a frequency band equal to or higher than the crossover band.
The measurement unit 211 outputs a measurement audio signal to the output terminal 113 (block A1), and acquires the measurement data by collecting the measurement audio signal with the microphone 114 (block A2).

The correction filter design unit 212 is based on the measurement data acquired by the measurement unit 211.
An equalizer that corrects the high frequency range above the crossover band is designed (block A3).
At the same time, the correction filter design unit 212 designs an equalizer that corrects the non-target region (bass) by prediction based on the difference between the target value and the measurement value in the crossover band (block A4).

(Second Embodiment)
A second embodiment of the present invention will be described with reference to FIGS. Description of the parts common to the first embodiment is omitted.
<Example 2: Correction for raising the high frequency range>
FIG. 7 shows an example in which the target characteristics are different from those in FIG. In this example, the position of B is higher than the position of A. If the equalizer is designed only for the high range as before, the result is as shown in FIG. 8 and the position of B is lowered. Therefore, as in the first embodiment, the balance can be corrected as shown in FIG.

By using the balance adjustment function, the user can adjust the difference in the volume balance between the low and high frequencies caused by the equalizer design that limits the bandwidth. According to the embodiment described above, the problems can be solved as follows.

Problem: In the technology that achieves high sound quality by measuring the characteristics of the user's earphones with the device, designing an equalizer based on the results, and listening to the earphones that measure the sound through the equalizer For example, while the equalizer is designed to correct the entire frequency band by combining two measurements, there is a method in which the measurement is performed once and either the high band or the low band is corrected.

However, in the latter case, there is a problem that correction cannot be performed for a band that is not the target even if the equalizer is correctly designed in the target band. As a method of alleviating this problem, there is a method of designing an equalizer based on prediction in the boundary band. However, there is a case where prediction is not possible, and there is a problem that cannot be said to be complete.

Solution: In the embodiment, for example, when a high frequency band is set as a target band, there is provided a means by which the user can adjust the volume balance between the low frequency band and the high frequency band caused by imperfect correction of the low frequency band. Is.

Specifically, an earphone is inserted into a headphone terminal of the device, and a measurement signal is output therefrom, and the measurement signal is collected using a microphone attached to the device, This is a method for calculating the characteristics of earphones. Based on open measurements, the user adjusts the volume balance between the low and high frequencies by correcting the high frequencies above the frequency band (boundary band) that switches from the low to high frequencies. Balance adjustment means that can be adjusted while listening to the sound. For example, it is possible to adjust the strength of the low range and the high range by moving a slider bar displayed in the application.

In addition, this invention is not limited to the said embodiment, In the range which does not deviate from the summary, it can implement in various modifications. Although the earphone sound signal processing method capable of adjusting the high sound has been described, an earphone sound signal processing method capable of adjusting the low sound may be used. The frequency range for increasing or decreasing the gain has been described for the case where the target band is the high band, but conversely, the low band may be the target band.

Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above-described embodiments. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements according to different embodiments may be appropriately combined.

DESCRIPTION OF SYMBOLS 1 ... Information processing apparatus (PC), 2 ... Sound reproduction apparatus, 11 ... Computer main body, 11a ... Cabinet, 11b ... Microphone hole, 12 ... Display unit, 13 ... LCD, 14 ... Keyboard, 15 ... Touchpad, 16 ... Earphone 101 ... CPU, 102 ... North bridge, 103 ... Main memory, 104 ... South bridge, 105 ... GPU, 106 ... Sound controller, 107 ... BIOS-ROM, 108 ... LAN controller, 109 ... H
DD, 110 ... ODD, 111 ... EC / KBC, 112 ... speaker, 113 ... output terminal,
114 ... Microphone, 121 ... OS, 122 ... Media player, 210 ... Signal measurement unit, 211 ... Measurement unit, 212 ... Correction filter design unit, 213 ... Target characteristic generation unit, 220 ...
Correction / reproduction unit, 220A ... correction unit, 220B ... reproduction unit, 221 ... correction filter, 222 ...
Acoustic signal reproduction unit, 223... Corrected acoustic data generation unit, 224... Acoustic data storage unit, 225.
Playback processing unit.

  Embodiments described herein relate generally to an acoustic signal processing technique suitable for an information processing apparatus having an output terminal to which an earphone can be connected.

  2. Description of the Related Art In recent years, information processing apparatuses that can be driven by a battery and that are called notebook PCs (Personal computers) are widely used. Some of these types of information processing devices are capable of outputting high-definition images and high-quality sound, such as advanced AV (Audio and visual) equivalent to stationary information processing devices. ) There are many things with functions. Such high-function model notebook PCs are often used as DVD (Digital versatile disc) players and music players.

  Such a high-performance model notebook PC includes an output terminal for outputting an audio signal to which an earphone can be connected together with a speaker. For example, in an environment in which sound cannot be output from a speaker, the user views the sound reproduced by the notebook PC by connecting an earphone to the output terminal.

  Each unspecified number of earphones that can be used by a user has characteristics. For this reason, various mechanisms for appropriately correcting the characteristics of an unspecified number of earphones have been proposed.

JP 2010-226329 A

However, the mechanism for correcting the characteristics of the earphones proposed so far has problems such as an increase in cost and a complicated work for the user.
It is an object of the present invention to provide an information processing apparatus and an acoustic signal processing method for the same that can correct the characteristics of the earphones with low cost and simple work.

  In order to solve the above-mentioned problem, according to the embodiment, an information processing apparatus includes an output terminal for outputting an audio signal, a microphone, and a measurement sound output from the output terminal and collected by the microphone. A measurement unit that measures a frequency characteristic of an earphone connected to the output terminal from a signal, a frequency characteristic of the earphone that is measured by the measurement unit, and a predetermined target frequency characteristic, from a low range to a high range The frequency characteristic of the sound output from the earphone is set to the predetermined target frequency characteristic for one of the high range higher than the crossover band that is the frequency band to be switched to or the lower range lower than the crossover band. Based on correction filter design means to design correction filter for correction and designation from outside Wherein the serial high frequency range, characterized by comprising an adjustment means for adjusting the volume balance between the low frequency range.

1 is a diagram illustrating an appearance of an information processing apparatus according to an embodiment. The figure which shows the system configuration | structure of the information processing apparatus of embodiment. 2 is an exemplary diagram showing functional blocks of a media player operating on the information processing apparatus according to the embodiment. FIG. The figure which shows the case where an equalizer is designed only in the high region (right side from the dotted line in a figure) of embodiment. The figure which shows the frequency characteristic of the earphone measured in the state shown in FIG. The figure which shows the state which suppressed the high region side of embodiment and reduced auditory annoyance. The figure which shows the case where an equalizer is designed only in the high region (right side from the dotted line in a figure) of embodiment. The figure which shows the frequency characteristic of the earphone measured in the state shown in FIG. The figure which shows the state which suppressed the high region side of embodiment and reduced auditory annoyance. The figure for demonstrating the effect which the information processing apparatus of embodiment makes it the shape which the whole increase / decrease amount changes with the increase / decrease in the value of the slider bar SB. The figure for demonstrating one application example of the acoustic signal process performed in order that the information processing apparatus of embodiment may correct | amend the frequency characteristic of an earphone. The flowchart which shows the flow of the acoustic signal process performed in order that the information processing apparatus of embodiment may correct | amend the frequency characteristic of an earphone.

Hereinafter, an embodiment of the present invention will be described.
(First embodiment)
A first embodiment will be described with reference to FIGS. 1 to 6 and FIGS. 11 to 12.
FIG. 1 is a diagram illustrating an external appearance of the information processing apparatus according to the present embodiment when the display unit is opened. This information processing apparatus is realized as, for example, a notebook-type PC 1 that can be driven by a battery and has portability.

  As shown in FIG. 1, the PC 1 includes a computer main body 11 and a display unit 12. The display unit 12 incorporates an LCD (Liquid crystal display) 13. The display unit 12 is attached to the computer main body 11 so as to be rotatable between an open position where the upper surface of the computer main body 11 is exposed and a closed position covering the upper surface of the computer main body 11.

  The computer main body 11 has a thin box-shaped housing, and a keyboard 14 and a touch pad 15 are arranged on the upper surface thereof. The computer main body 11 has a built-in microphone, and a microphone hole is provided in the front portion of the housing so that the microphone can efficiently collect sound. Further, an output terminal for outputting an audio signal to which the earphone 16 can be connected is provided on the side surface of the casing of the computer main body 11.

  When the measurement audio signal is output to the output terminal (to which the earphone 16 is connected) with the earphone 16 in contact with the microphone hole, the measurement audio signal is picked up by the microphone. Characteristics can be measured. The information processing apparatus (PC1) of the present embodiment includes a mechanism for correcting the characteristics of the earphone 16 that can be measured in this way with a low-cost and simple operation. This point will be described in detail below. .

FIG. 2 is a diagram illustrating a system configuration of the PC 1.
As shown in FIG. 2, the PC 1 includes a CPU (Central processing unit) 101, a North Bridge 102, a main memory 103, a South Bridge 104, a GPU (Graphics).
processing unit) 105. The PC 1 includes a sound controller 106, a basic input / output system (BIOS) -read only memory (ROM) 107, a local area network (LAN) controller 108, a hard disk drive (HDD) 109, and an optical disc drive (ODD) 110. And EC / KBC (Embedded
controller / Keyboard controller) 111.

  The CPU 101 is a processor that controls the operation of the PC 1 and executes various programs loaded from the HDD 109 to the main memory 103. Among the various programs executed by the CPU 101, there are applications such as an OS (Operating system) 121 that manages resource management and a media player 122 (described later) that operates under the OS 121. The media player 122 is application software for reproducing moving image (video) and audio files. The CPU 101 also executes the BIOS stored in the BIOS-ROM 107. The BIOS is a program for hardware control.

  The north bridge 102 operates as a bridge device that connects between the CPU 101 and the south bridge 104 and also operates as a memory controller that controls access to the main memory 103. The north bridge 102 has a function of executing communication with the GPU 105.

  The GPU 105 is a display controller that performs image display on the LCD 13 incorporated in the display unit 12. Further, the GPU 105 includes an accelerator that draws an image to be displayed by various programs in place of the CPU 101.

  The south bridge 104 operates as a memory controller that controls access to the BIOS-ROM 107. Further, the south bridge 104 includes an IDE (Integrated Device Electronics) controller for controlling the HDD 109 and the ODD 110. Further, the south bridge 104 has a function of executing communication with the sound controller 106.

  The sound controller 106 is a sound source device, and converts a digital signal into an electrical signal in order to output audio data to be reproduced to a speaker 112 or an output terminal 113 (provided on the side surface of the casing of the computer main body 11). Circuits such as a D / A converter that performs amplification and an amplifier that amplifies an electric signal. The sound controller 106 includes a circuit such as an A / D converter that converts an electric signal input from the microphone 114 (built in the computer main body 11 described above) into a digital signal.

  The EC / KBC 111 is a one-chip microcomputer in which an embedded controller for performing power management of the PC 1 and a keyboard controller for controlling the keyboard 14 and the touch pad 15 are integrated.

FIG. 3 is a diagram showing functional blocks of the media player 122 operating on the PC 1 having the system configuration as described above.
As shown in FIG. 3, the media player 122 includes a signal measurement unit 210 and a correction / playback unit 220. The signal measurement unit 210 includes a measurement unit 211, a correction filter design unit 212, and a target characteristic generation unit 213, and the correction / reproduction unit 220 includes a correction filter 221 and an acoustic signal reproduction unit 222.

  Here, in order to help understand the main contents of the present application, the relationship between the application P2011-166782 by the same inventors as the present application and the present application will be described first. This prior application provides the measurement of the earphone characteristics necessary for correcting the acoustic characteristics of the earphones with an equalizer in a form that can be measured by the user and at a low cost.

  That is, an earphone is inserted into a headphone terminal of the device, a measurement signal is output therefrom, the measurement signal is collected using a microphone attached to the device, and the characteristics of the earphone are determined from the collected signal. In this calculation method, the correction frequency is limited, and the earphone frequency characteristic of the target band is obtained and corrected by performing only one measurement of either the close contact measurement or the open measurement only.

  However, in this method, in the case of open measurement, an equalizer that corrects only the high frequency is designed based on the measurement of only the high frequency. There is a problem that the balance between the low and high frequencies may be lost. Therefore, after designing the equalizer, a function was provided to adjust the balance between the low and high frequencies, allowing the user to adjust the balance according to their preferences as follows.

<Example 1: Correction for lowering high range>
In the embodiment of FIG. 1, the earphone 16 is inserted into a headphone output terminal (not shown) of the device (computer main body 11), a measurement signal is sent from the headphone output terminal, and this signal is collected by a microphone. Measure the characteristics of the earphones. Examples of measurement signals include white noise, pink noise, and TSP signals. A frequency characteristic (measurement characteristic) is obtained from the measurement signal acquired by the microphone.

  FIG. 4 shows measurement characteristics, target characteristics, and equalizer characteristics with the horizontal axis representing frequency and the vertical axis representing amplitude. The target characteristic is an ideal frequency characteristic of an earphone mounted in advance on the device. The equalizer is designed to match the measurement characteristics to the target characteristics. By applying the designed equalizer to the signal to be reproduced, it is possible to obtain sound quality such as target characteristics with the user's earphone used for measurement.

  By the way, when the frequency region in which the equalizer is designed is limited as in the previous application, the volume balance between the low range and the high range may be lost. FIG. 4 shows a case where the equalizer is designed only in the high region (right side from the dotted line in the figure). In this case, the equalizer characteristic is flat (gain 0) in the low range and is not corrected, and has a shape that brings the measurement characteristic close to the target characteristic in the high range. As a result, the frequency characteristic of the earphone to which the designed equalizer is applied is as shown in FIG. For the high frequency, the target characteristics and the shape are the same, and the sound is as designed. However, for the low frequency, the correction amount is zero, and the characteristics of the original user earphone remain. Although it is a reasonable result under the condition that the band is limited, there may be a case where a high tone is heard audibly. As the cause, there is a problem that the balance of the volume of the low range and the high range is broken. In the target characteristics shown in FIG. 4, A is higher at the level near the low band A and at the level near the high band B. On the other hand, the high region B is higher in FIG. This is because only B has been lifted where correction should be made while maintaining the balance between A and B. Since A is outside the target band, it is difficult to consider in the correction that limits the band.

  Therefore, after designing the equalizer, a filter that controls the high frequency by the user's operation is added, and a function that adjusts based on the auditory impression is added. For example, the application described in FIG. 2 is provided with a display means on the LCD 13 for a slider bar (with scale value display), and a mechanism that allows the user to adjust while listening to the sound after designing the equalizer is configured. The shape of the filter that controls the high range is experimentally determined, but a filter whose gain increases or decreases as the frequency increases is prepared, and the overall increase / decrease amount changes as the value of the slider bar SB increases / decreases. The shape is effective (see FIG. 10).

  In order to prevent the shape outside the target band from changing, it is also effective to set the frequency range in which the gain is increased or decreased only to the target band. Furthermore, when the target band is a high band, it is also effective to increase / decrease only the band of 2 kHz or higher where the annoyance starts to be a concern. In addition to the slider bar, other UIs such as dials, numerical input, or normal, high, low, and three-level push buttons may be used. By adopting such a configuration, it becomes possible to suppress the high frequency side as shown by the white arrow in FIG. In addition, there is an advantage that the equalizer design error due to variations in microphone characteristics for each product can be corrected to some extent by the user.

FIG. 11 is a diagram for explaining an application example of acoustic signal processing executed by the PC 1 of the present embodiment to correct the frequency characteristics of the earphone.
Here, even when a device such as a portable audio player (sound reproduction device 2) that is difficult to include an arbitrary correction filter is used, when the user views music using the earphone 16, the above-described correction is performed. An example for achieving the effect will be described.

  In this case, the correction / playback unit 220 of the media player 122 shown in FIG. 3 is divided into a correction unit 220A and a playback unit 220B, and the playback unit 220B is disposed on the side of the sound playback device 2 externally connected to the PC 1. .

  In the example described above, the sound reproduced by the acoustic signal reproduction unit 222 is corrected using the correction filter 221 (to which the coefficient created by the correction filter design unit 212 of the signal measurement unit 210 is applied), and after the correction. The audio signal was output from the output terminal 113. On the other hand, in the application example shown in FIG. 11, the audio signal corrected using the correction filter 221 is supplied to the corrected acoustic data generation unit 223. The corrected acoustic data generation unit 223 encodes the supplied audio signal to generate corrected acoustic data, and stores the generated corrected acoustic data in the acoustic data storage unit 224 of the sound reproduction device 2. And the reproduction | regeneration processing part 225 of the reproduction | regeneration part 220B arrange | positioned at the sound reproduction apparatus 2 reproduce | regenerates the correction | amendment acoustic data stored in the acoustic data memory | storage part 224, and outputs it from an output terminal.

  That is, by transferring the corrected data to the reproduction unit 220B, it is possible to obtain the correction effect during reproduction even in a device (sound reproduction apparatus 2) that cannot perform arbitrary correction.

FIG. 12 is a flowchart showing the flow of acoustic signal processing executed by the PC 1 to correct the earphone frequency characteristics.
Here, it is assumed that the main correction target is a frequency band equal to or higher than the crossover band.
The measurement unit 211 outputs a measurement audio signal to the output terminal 113 (block A1), and acquires the measurement data by collecting the measurement audio signal with the microphone 114 (block A2).

  The correction filter design unit 212 designs an equalizer that corrects the high frequency range above the crossover band based on the measurement data acquired by the measurement unit 211 (block A3). At the same time, the correction filter design unit 212 designs an equalizer that corrects the non-target region (bass) by prediction based on the difference between the target value and the measurement value in the crossover band (block A4).

(Second Embodiment)
A second embodiment of the present invention will be described with reference to FIGS. Description of the parts common to the first embodiment is omitted.
<Example 2: Correction for raising the high frequency range>
FIG. 7 shows an example in which the target characteristics are different from those in FIG. In this example, the position of B is higher than the position of A. If the equalizer is designed only for the high range as before, the result is as shown in FIG. 8 and the position of B is lowered. Therefore, as in the first embodiment, the balance can be corrected as shown in FIG.

  By using the balance adjustment function, the user can adjust the difference in the volume balance between the low and high frequencies caused by the equalizer design that limits the bandwidth. According to the embodiment described above, the problems can be solved as follows.

  Problem: In the technology that realizes high sound quality by measuring the characteristics of the user's earphones with the device, designing an equalizer that achieves high sound quality based on the results, and listening to the earphones that measure the sound through this equalizer For example, while the equalizer is designed to correct the entire frequency band by combining two measurements, there is a method in which the measurement is performed once and either the high band or the low band is corrected.

  However, in the latter case, there is a problem that correction cannot be performed for a band that is not the target even if the equalizer is correctly designed in the target band. As a method of alleviating this problem, there is a method of designing an equalizer based on prediction in the boundary band. However, there is a case where prediction is not possible, and there is a problem that cannot be said to be complete.

  Solution: In the embodiment, for example, when a high frequency band is set as a target band, there is provided a means by which the user can adjust the volume balance between the low frequency band and the high frequency band caused by imperfect correction of the low frequency band. Is.

  Specifically, an earphone is inserted into a headphone terminal of the device, and a measurement signal is output therefrom, and the measurement signal is collected using a microphone attached to the device, This is a method for calculating the characteristics of earphones. Based on open measurements, the user adjusts the volume balance between the low and high frequencies by correcting the high frequencies above the frequency band (boundary band) that switches from the low to high frequencies. Balance adjustment means that can be adjusted while listening to the sound. For example, it is possible to adjust the strength of the low range and the high range by moving a slider bar displayed in the application.

  In addition, this invention is not limited to the said embodiment, In the range which does not deviate from the summary, it can implement in various modifications. Although the earphone sound signal processing method capable of adjusting the high sound has been described, an earphone sound signal processing method capable of adjusting the low sound may be used. The frequency range for increasing or decreasing the gain has been described for the case where the target band is the high band, but conversely, the low band may be the target band.

  Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above-described embodiments. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements according to different embodiments may be appropriately combined.

  DESCRIPTION OF SYMBOLS 1 ... Information processing apparatus (PC), 2 ... Sound reproduction apparatus, 11 ... Computer main body, 11a ... Cabinet, 11b ... Microphone hole, 12 ... Display unit, 13 ... LCD, 14 ... Keyboard, 15 ... Touchpad, 16 ... Earphone 101 ... CPU, 102 ... North Bridge, 103 ... Main Memory, 104 ... South Bridge, 105 ... GPU, 106 ... Sound Controller, 107 ... BIOS-ROM, 108 ... LAN Controller, 109 ... HDD, 110 ... ODD, 111 ... EC / KBC, 112 ... Speaker, 113 ... Output terminal, 114 ... Microphone, 121 ... OS, 122 ... Media player, 210 ... Signal measurement unit, 211 ... Measurement unit, 212 ... Correction filter design unit, 213 ... Target characteristic generation unit 220 ... correction / playback unit 220A ... correction , 220B ... reproduction section, 221 ... correction filter, 222 ... audio signal reproducing unit, 223 ... correction sound data generation unit, 224 ... sound data storage section, 225 ... playback processing unit.

Claims (6)

An output terminal for outputting an audio signal;
A microphone,
Measuring means for measuring a frequency characteristic of an earphone connected to the output terminal from an audio signal for measurement output from the output terminal and collected by the microphone;
Based on the frequency characteristics of the earphones measured by the measuring means and a predetermined target frequency characteristic, from a high sound range higher than a crossover band that is a frequency band that switches from a low sound range to a high sound range or from the crossover band A correction filter design means for designing a correction filter for correcting the frequency characteristic of the sound output from the earphone to the predetermined target frequency characteristic with respect to one of the lower low frequency ranges;
Adjusting means for adjusting a volume balance between the high range and the low range based on designation from the outside;
An information processing apparatus comprising: The correction filter design means is based on a difference between a frequency characteristic of the earphone measured by the measurement means in the crossover band and the target frequency characteristic, and a higher sound range higher than the crossover band or the crossover band. 2. The correction filter is designed to predict a difference between the frequency characteristic of the earphone and the target frequency characteristic for the other low frequency range of the lower low frequency range, and to further perform correction using the predicted difference as a correction amount. The information processing apparatus described in 1. When correcting the frequency characteristics of the earphone for a high frequency range higher than the crossover band, the earphone is in contact with the microphone so that a gap is provided between the earphone and the microphone. The information processing apparatus according to claim 1, wherein a sound signal for measurement output from an output terminal is collected by the microphone. When correcting the frequency characteristics of the earphone for a low frequency range lower than the crossover band, output from the output terminal in a state where the earphone is in contact with the microphone so that the earphone and the microphone are in close contact with each other. The information processing apparatus according to claim 1, wherein the measured audio signal is collected by the microphone. 2. A corrected audio data generating means for generating corrected audio data obtained by re-encoding the audio signal obtained by reproducing audio data obtained by encoding an audio signal by performing correction by the correction filter. The information processing apparatus described in 1. Measure the frequency characteristics of the earphone connected to the output terminal from the audio signal for measurement output from the output terminal for outputting the audio signal and collected by the microphone,
Based on the measured frequency characteristic of the earphone and a predetermined target frequency characteristic, a high frequency range that is higher than a crossover band, which is a frequency band that switches from a low frequency range to a high frequency range, or a low frequency range that is lower than the crossover band Designing a correction filter for correcting the frequency characteristic of the sound output from the earphone to the predetermined target frequency characteristic for one of the sound ranges of
Adjust the volume balance between the high and low frequencies based on external designations;
An acoustic signal processing method for an information processing apparatus.

Images