close

Вход

Забыли?

вход по аккаунту

?

JP2008228198

код для вставкиСкачать
Patent Translate
Powered by EPO and Google
Notice
This translation is machine-generated. It cannot be guaranteed that it is intelligible, accurate,
complete, reliable or fit for specific purposes. Critical decisions, such as commercially relevant or
financial decisions, should not be based on machine-translation output.
DESCRIPTION JP2008228198
PROBLEM TO BE SOLVED: To provide a reproduction sound adjusting device capable of adjusting
reproduction sound so that it is easy to distinguish between the reproduction sound and the
ambient sound without the surrounding sound being masked by the reproduction sound.
SOLUTION: A microphone 14 detects an ambient sound and generates an ambient sound signal.
The Fourier transform processing unit 15 Fourier-transforms the generated ambient sound signal
to acquire the frequency characteristic of the ambient sound signal. The frequency band
specifying unit 16 sets at least one frequency band among the predetermined n frequency bands
BW1 to BWn based on the acquired frequency characteristic of the ambient sound signal as a
target frequency band related to the feature of the ambient sound. Identified as BWk. The
correction parameter setting unit 17 and the multiband equalizer 11 change the gain in the
specified target frequency band BWk with respect to the audio signal reproduced as the
reproduction sound so that the reproduction sound and the ambient sound can be distinguished.
[Selected figure] Figure 1
Reproduction sound adjustment device and reproduction sound adjustment method
[0001]
The present invention relates to a reproduction sound adjustment device and a reproduction
sound adjustment method for adjusting a reproduction sound to be reproduced and outputted
based on an ambient sound including a sound emitted in the surroundings, and in particular, a
television, a DVD player, a radio, a CD player And a reproduction sound adjustment device and a
reproduction sound adjustment method which are connected to an MP3 player, a telephone set,
and the like and adjust reproduction sound output from these devices.
08-05-2019
1
[0002]
One of the conventionally known adjustment devices of this type adjusts the reproduced sound
so that the volume from the speaker increases as the surrounding noise increases (see Patent
Document 1).
That is, this adjusting device is reproduced by the speaker according to the microphone for
collecting the ambient noise, the circuit for detecting the level of the stationary noise collected,
and the detected noise level. And a circuit for changing the amplification factor of the audio
signal. According to this device, the amplification factor of the audio signal is set to be larger as
the noise level is larger, whereby the volume of the reproduced sound from the speaker becomes
larger. In addition, a telephone is provided with a close talk circuit in which microphones are
arranged as a pair on the front and back of the telephone and both microphone inputs are input
to the differential input terminal of the differential amplifier to mask ambient sound (see Patent
Document 2) There is also a proposal for
[0003]
JP-A-11-261355 JP-A-61-214852
[0004]
However, in the reproduction sound adjustment device according to the conventional patent
document 1, when the noise is large, the volume from the speaker is increased, and therefore,
when a sound that needs to be distinguished from the reproduction sound is emitted from near
this device, For example, even if another person near this device speaks to the person listening to
the music played through the playback sound adjustment device, the sound emitted around the
device will be loud from the speaker It may be masked by the adjusted reproduction sound.
Further, the voice adjustment device shown in Patent Document 2 and the like is a technique for
masking ambient sound in order to give priority to speech and playback sound.
[0005]
The object of the present invention is to distinguish between the sound emitted in the
surroundings and the reproduced sound without masking the sounds emitted in the surroundings
08-05-2019
2
by the reproduced sound and without completely masking the sounds emitted in the
surroundings. It is an object of the present invention to provide a reproduction sound adjustment
device and a reproduction sound adjustment method capable of adjusting reproduction sound to
be easy.
[0006]
The reproduction sound adjustment device according to the present invention adjusts the
reproduction sound to be reproduced and outputted based on the ambient sound, and the
ambient sound detection means, the ambient sound characteristic acquisition means, the
frequency band identification means, the voice adjustment And means.
The ambient sound mentioned here mainly includes the sound emitted around the present
playback sound adjustment device. The ambient sound detection means detects the ambient
sound and generates an ambient sound signal, and the ambient sound characteristic acquisition
means acquires the frequency characteristic of the generated ambient sound signal. The
frequency band specifying means specifies at least one frequency band among a plurality of
predetermined frequency bands as a target frequency band related to the characteristic of the
ambient sound based on the frequency characteristic of the acquired ambient sound signal. The
sound adjusting means changes the gain of the sound signal reproduced as the reproduction
sound in the specified target frequency band. Further, in the reproduction sound adjusting
device, the sound adjusting means may include a correction parameter setting means and an
equalizer. The correction parameter setting means sets a correction parameter for correcting the
gain of the audio signal in the target frequency band identified by the frequency band
identification means. The equalizer increases or decreases the gain in the specified target
frequency band based on the set correction parameter. Further, (1) in the reproduction sound
adjusting apparatus in which the sound adjusting means includes the correction parameter
setting means and the equalizer, the frequency band specifying means may be configured as
follows. That is, the frequency band specifying means specifies, as the target frequency band, a
frequency band including a frequency at which the intensity of the ambient sound is maximized
or minimized. In addition, in this reproduction sound adjusting device, the correction parameter
setting means decreases the gain of the audio signal in the target frequency band including the
frequency at which the intensity of the ambient sound is maximal, and the intensity of the
ambient sound is minimized. The correction parameter may be set to increase the gain of the
audio signal in the target frequency band including the frequency. Further, in the reproduced
sound adjusting device according to (1), the correction parameter setting means is an ambient
sound signal acquired by the ambient sound characteristic acquiring means for the correction
parameter in the target frequency band specified by the frequency band specifying means. It may
08-05-2019
3
be set using the intensity of ambient sound in this target frequency band obtained on the basis of
the frequency characteristic of H and the auditory characteristic value in the target frequency
band obtained on the basis of the auditory characteristic of a person designated in advance. In
addition, (2) in the above-mentioned reproduction sound adjustment device in which the sound
adjustment means includes the correction parameter setting means and the equalizer, the
reproduction sound characteristic acquisition means may be provided and the frequency band
identification means may be configured as follows. That is, the reproduction sound characteristic
acquisition means acquires the frequency characteristic of the audio signal.
The frequency band specifying means is, based on the target frequency band, a frequency
characteristic of the audio signal acquired by the reproduction sound characteristic acquiring
means and a frequency characteristic of the ambient sound signal acquired by the ambient sound
characteristic acquiring means. A frequency band including frequencies at which the difference
between the intensity of the sound and the intensity of the reproduced sound by the audio signal
becomes maximum or minimum is specified. In this reproduction sound adjusting device, the
correction parameter setting means decreases the gain of the sound signal in the target
frequency band including the frequency at which the difference between the strength of the
ambient sound and the strength of the reproduction sound of the sound signal becomes
maximum. The correction parameter may be set to increase the gain in the target frequency band
including the frequency at which the difference is minimized. Further, in the reproduced sound
adjusting device of (2), the correction parameter setting means is an ambient sound signal
acquired by the ambient sound characteristic acquiring means for the correction parameter in
the target frequency band specified by the frequency band specifying means. Comparing the
intensity of the ambient sound in the target frequency band obtained based on the frequency
characteristics of the sound and the intensity of the playback sound by the audio signal in the
target frequency band obtained based on the frequency characteristics of the audio signal
acquired by the reproduced sound characteristic acquisition means It may be set using the
characteristic comparison value obtained as a result and the auditory characteristic value in the
target frequency band obtained based on the auditory characteristic of the person designated in
advance. The reproduction sound adjustment method according to the present invention is to
adjust the reproduction sound to be reproduced and outputted, and comprises a detection step, a
first acquisition step, a identification step, and a change step. Do. The ambient sound mentioned
here mainly includes the sound emitted around the present playback sound adjustment device. In
the detection step, the ambient sound is detected to generate an ambient sound signal, and in the
first acquisition step, the frequency characteristic of the generated ambient sound signal is
obtained. In the identifying step, at least one of the predetermined plurality of frequency bands is
identified as a target frequency band related to the characteristics of the ambient sound based on
the frequency characteristic of the acquired ambient sound signal. In the changing step, the gain
of the audio signal reproduced as the reproduction sound is changed in the specified target
frequency band. The reproduction sound adjustment method may include the second acquisition
08-05-2019
4
step, and the above identification step may be configured as follows. In the second acquisition
step, frequency characteristics of the audio signal are acquired. In the identification step, based
on the frequency characteristics of the audio signal acquired in the second acquisition step and
the frequency characteristics of the ambient sound signal acquired in the first acquisition step,
reproduction by the intensity of the ambient sound and the audio signal A frequency band
including a frequency at which the difference with the sound intensity is maximum or minimum
is specified as the target frequency band.
[0007]
According to the present invention, among the predetermined plural frequency bands, the
frequency band related to the characteristics of the ambient sound is specified as the target
frequency band based on the frequency characteristics of the ambient sound, the frequency
characteristics of the playback sound, etc. The gain in the specified target frequency band is
changed with respect to the audio signal of the reproduction sound so that the sound of the
background sound and the ambient sound can be easily distinguished. As an example, this target
frequency band is specified as a frequency band including a frequency at which the difference
between the intensity of the ambient sound output from the microphone and the intensity of the
reproduction sound of the audio signal is maximized, and the gain of the audio signal The change
is made so as to reduce the gain in the frequency band where the difference between the
intensities of the two sounds is maximal. For this reason, it is possible to prevent the occurrence
of the inconvenience that the ambient sound is masked by the high-volume reproduced sound as
in the conventional device and the ambient sound which needs to be heard can not be heard.
[0008]
The best mode for carrying out the present invention will be described below with reference to
the drawings. First Embodiment FIG. 1 shows a first embodiment of a reproduction sound
adjusting apparatus according to the present invention. The reproduction sound adjustment
device 1 reproduces the adjusted reproduction sound while adjusting the reproduction sound
based on the sound emitted around. In FIG. 1, the functions of the units 11, 13, and 15 to 17
except the speaker 12 and the microphone 14 can be realized by a program, and in this case, the
reproduction sound adjustment device 1 includes a microprocessor, RAM, ROM, and input /
output. The device includes an interface and the like. All or part of each of the units 11, 13, 15
may be configured by a digital circuit or the like.
08-05-2019
5
[0009]
The multiband equalizer 11 can change the gain in each of n (n is an integer of 2 or more)
frequency bands BW1 to BWn with respect to an audio signal reproduced as reproduced sound.
Here, this audio signal is a digital signal of a predetermined number of bits, and a graphic
equalizer is used as the multiband equalizer 11. For example, in the multiband equalizer 11, 25
Hz to 20 kHz are divided into 30 frequency bands BW1 to BW30 for each predetermined
frequency, and the gain can be changed for each frequency band. A parametric equalizer may be
used as the multiband equalizer 11. In the reproduction sound adjusting apparatus 1, the
adjustment of the gain for each frequency band in the multiband equalizer 11 includes the
frequency characteristics of the reproduction sound (audio signal) and the surrounding including
the sound emitted around the reproduction sound adjusting apparatus 1. It is automatically
performed based on the frequency characteristic of the sound (ambient sound signal). The
speaker 12 appropriately amplifies the audio signal whose gain of each frequency band has been
adjusted by the multiband equalizer 11 and outputs reproduced sound.
[0010]
The Fourier transform processing unit 13 acquires the frequency characteristics of the audio
signal by performing (discrete) Fourier transform of the audio signal to be reproduced sound.
The microphone 14 detects the sound around the reproduction sound adjustment device 1 to
generate an ambient sound signal, and the Fourier transform processing unit 15 Fouriertransforms the ambient sound signal to obtain frequency characteristics of the ambient sound
signal. get. The ambient sound referred to here mainly includes the component of the sound
emitted in the periphery, but also includes the component of the reproduced sound emitted from
the speaker 12 after adjustment by the present reproduced sound adjusting device 1.
[0011]
The frequency band identification unit 16 uses the multiband equalizer 11 based on the
frequency characteristics of the audio signal acquired by the Fourier transform processing unit
13 and the frequency characteristics of the ambient sound signal acquired by the Fourier
transform processing unit 15. At least one frequency band of all frequency bands BW1 to BWn
which can change the gain is specified as a target frequency band BWk (k is an integer from 2 to
n) related to the characteristics of the ambient sound. The correction parameter setting unit 17
sets a correction parameter Pk for correcting the gain of the audio signal in the specified target
08-05-2019
6
frequency band BWk. The multiband equalizer 11 is configured to increase or decrease the gain
of the audio signal in the target frequency band BWk by this correction parameter Pk, and
therefore the frequency band identification unit 16 as the audio adjustment means and the
multiband The operation of the equalizer 11 makes it possible to distinguish between the
reproduced sound and the ambient sound.
[0012]
FIG. 2 is a diagram for describing identification of a target frequency band in the frequency band
identification unit 16 and setting of correction parameters in the correction parameter setting
unit 17. In FIGS. 2A and 2B, the solid line schematically shows the intensity of the reproduced
sound after the Fourier transform, and the broken line schematically shows the intensity of the
ambient sound after the Fourier transform. It is assumed that the reproduced sound emitted from
the speaker 12 is attenuated to some extent and included in the ambient sound. Further, in FIG.
2B, the alternate long and short dash line indicates the intensity of the reproduced sound after
the gain is adjusted. In the reproduction sound adjusting apparatus 1, as shown in FIG. 2 (b), the
gain of the audio signal in each frequency band is adjusted by the correction parameter so that
the ambient sound is separated from the reproduction sound.
[0013]
That is, in the vicinity of the frequencies fA and fC, the intensity of the ambient sound is a
maximum (peak, peak to the top), and in the vicinity of the frequency fB, the intensity of the
ambient sound is a minimum (valley, peak to the bottom) It has become. The frequency band
specifying unit 16 extracts such a feature of the ambient sound or a feature for the reproduced
sound of the ambient sound, and identifies the frequency band including the characteristic
frequency as the target frequency band. Specifically, the correction parameter setting unit 17
sets the gain of the reproduced sound in the frequency band including the frequency fA and the
frequency band including the frequency fC such that the feature of the ambient sound is
separated and emphasized from the reproduced sound. The correction parameter for adjusting
the gain is set such that the gain of the reproduced sound is increased in the frequency band
including the frequency fB.
[0014]
08-05-2019
7
In particular, in FIG. 2, the intensity of the reproduced sound is minimized near the frequencies
fA and fc where the intensity of the ambient sound is maximal, and near the frequency fB where
the intensity of the ambient sound is minimized Although the intensity of the reproduced sound
is maximized, the multiband equalizer 11 can separate the ambient sound and the reproduced
sound in other situations as well. That is, for example, even in the situation where the intensity of
the reproduced sound does not take an extreme value in the vicinity of the frequency at which
the intensity of the ambient sound becomes maximal, and the intensity of the reproduced sound
becomes maximal, the multiband equalizer 11 It is possible to separate the ambient sound and
the reproduced sound by adjusting the gain of the reproduced sound so that the difference
between the ambient sound and the reproduced sound is not excessively large.
[0015]
Details of an example of a process for specifying a target frequency band related to such a
feature of ambient sound will be described. FIG. 3 is a diagram for explaining this process. Here,
a function representing the difference between the intensity of the ambient sound and the
intensity of the reproduced sound is set as the characteristic comparison function B (f) having the
frequency f as an argument, and the dashed-dotted line in FIG. It represents a function B (f). The
characteristic comparison value by the characteristic comparison function B (f), that is, the
difference between the intensity of the ambient sound and the intensity of the reproduced sound
is maximum at the frequencies fA1 and fC1, and is minimum at the frequency fB1. . The
frequency band identification unit 16 extracts extreme values of these characteristic comparison
values. That is, the frequency band identification unit 16 obtains a frequency at which the
differential value of the difference obtained by subtracting the intensity of the reproduction
sound from the intensity of the ambient sound is zero. Depending on whether the differential
value of this difference changes from positive to negative or from negative to positive, it is
determined whether the corresponding difference is a maximum value or a minimum value.
Then, the frequency band specifying unit 16 specifies a frequency band corresponding to these
extreme values. The frequency band identification unit 16 outputs, to the correction parameter
setting unit 17, data for identifying the target frequency band, data representing the intensity of
ambient sound, data representing the intensity of reproduced sound, and the like for the
identified target frequency band. .
[0016]
The correction parameter setting unit 17 sets, as the correction parameter PA1, the gain of the
reproduced sound to be reduced in the target frequency band including the frequency fA1 at
08-05-2019
8
which the characteristic comparison value is maximal, the object frequency including the
frequency fC1 at which the characteristic comparison value is maximal. The gain of the
reproduced sound to be reduced in the band is set as the correction parameter PC1. Further, the
gain of the reproduced sound to be increased in the target frequency band including the
frequency fB1 at which the characteristic comparison value is minimized is set as the correction
parameter PB1. The setting of the correction parameter here can be performed based on the
center frequency of the target frequency band for which the gain is increased or decreased, the
intensity of the ambient sound, and the intensity of the reproduced sound.
[0017]
More specifically, the correction parameter setting unit 17 calculates a correction function G (f)
with the frequency (or the center frequency of each of the frequency bands BW1 to BWn) f as an
argument based on the following equation 1 The correction parameter Pk in any one of the
frequency bands BW1 to BWn corresponding to the frequency f may be set by the correction
function G (f).
[0018]
Here, k is a predetermined constant used as a reference for gain adjustment.
Each of the functions A (f) and B (f) describes the correspondence with f on a predetermined
table. The correction parameter setting unit 17 appropriately calculates the correction function G
(f) with reference to these tables.
[0019]
The function A (f) is an auditory characteristic function determined in consideration of human
auditory characteristics. That is, the auditory characteristic function A (f) is adjusted by
experiments or simulations in accordance with the human auditory characteristics in the low
frequency range, the medium frequency range and the high frequency range. By using the
absolute value Df of the difference between the intensity of the ambient sound and the intensity
of the reproduced sound in addition to the frequency as the argument of the auditory
characteristic function A, the auditory characteristic is such that the ambient sound is less likely
to be masked by the reproduced sound. The auditory characteristic value in the function A can be
set in advance. For example, when the absolute value Df is smaller than a predetermined lower
08-05-2019
9
limit, the auditory characteristic function A (f) is set to 0, and when the absolute value Df is larger
than a predetermined upper limit, the auditory characteristic function A (f) is fixed. It can be a
predetermined value. According to such setting of the auditory characteristic function A (f), the
correction parameter can be corrected more appropriately in accordance with the human
auditory characteristic. Also, although the function B (f) is a function representing the difference
between the intensity of the ambient sound and the intensity of the playback sound as described
above, other predetermined characteristic comparisons used to compare the ambient sound and
the playback sound You may set a function.
[0020]
Then, the correction parameter setting unit 17 sets the correction parameter so that the gain is
adjusted as follows in the adjacent frequency band adjacent to the specified target frequency
band. FIG. 4 is a diagram for explaining the setting of the correction parameter. For example,
based on the gain reduction width g of the target frequency band BWk including the frequency
fA, 90 of the gain reduction width g as a reference in the adjacent frequency bands BWk-1 and
BWk + 1 on both sides of the target frequency band BWk. Decrease the gain by%. Further, with
respect to adjacent frequency bands BWk-2 and BWk + 2 on both sides thereof, the gain is
decreased by 80% of the reference gain decrease width g, and these are repeated. That is, from
the central target frequency band BWk which changes the gain to the maximum, to the adjacent
frequency bands BWk-1, BWk-2, ... on the low frequency side, and the adjacent frequency bands
BWk + 1, BWk + 1 on the high frequency side Then, the correction parameter setting unit 17 sets
the correction parameter so that the change in gain is smooth. By this, the sound quality of the
reproduction sound before adjustment is maintained as much as possible.
[0021]
According to the present reproduction sound adjusting device 1, the target frequency band
relating to the feature of the ambient sound with respect to the reproduction sound is specified
based on the frequency characteristic of the playback sound and the frequency characteristic of
the ambient sound, and the reproduction sound and the ambient sound can be easily
distinguished. As such, the gain of the audio signal is increased or decreased in the identified
target frequency band. For this reason, it is possible to prevent the occurrence of the
inconvenience that the ambient sound is masked by the high-volume reproduced sound as in the
conventional device and the ambient sound can not be heard.
08-05-2019
10
[0022]
For example, when an announcer is reading news on television news etc, it is assumed that a
person in front of the television talks to a person watching the television. Usually, in such a
situation, the voice of the announcer and the voice of the person in front of the television may
overlap in similar frequency bands, making it difficult to distinguish one voice from the other.
According to the present reproduction sound adjustment device 1, the voice quality of the
announcer's voice is adjusted according to the voice of the person in front of the television so
that the voice of the person in front of the television and the voice of the announcer can be
separated and distinguished. Be done.
[0023]
Second Embodiment Next, a second embodiment of the reproduced sound adjusting device
according to the present invention will be described. The present embodiment differs from the
first embodiment in that the Fourier transform processing unit 13 is not provided. FIG. 5 is a
diagram for explaining the process for identifying the frequency band related to the feature of
the ambient sound. The configuration and operation relating to processing other than the
processing described here conform to the first embodiment. The intensity of the ambient sound
is maximized at the frequencies fA2 and fC2 and minimized at the frequency fB2. The frequency
band identification unit 16 extracts these extreme values. The correction parameter setting unit
17 reduces the gain of the reproduced sound by a predetermined gain in the frequency band
including the frequency fA2 at which the intensity of the ambient sound reaches a maximum and
the frequency band including the frequency fC2 at a maximum. Further, the correction parameter
is set so as to increase the gain of the reproduced sound by a predetermined gain in the
frequency band including the frequency fB2 at which the intensity of the ambient sound is
minimized. In particular, in the present reproduction sound adjustment apparatus, the frequency
characteristic of the reproduction sound is not used at the time of setting the correction
parameter, and hence the Fourier transformation of the reproduction sound as in the Fourier
transformation processing unit 13 is not required.
[0024]
According to the present reproduction sound adjusting device, the target frequency band related
to the characteristics of the ambient sound is specified based on the frequency characteristics of
the ambient sound, and the specified target frequency band is easily identified so that the
08-05-2019
11
reproduced sound and the ambient sound can be easily distinguished. , The gain of the
reproduced audio signal is increased or decreased. Although this device has a simpler
configuration than the above-described first embodiment, it can similarly avoid the problems
caused by the conventional device.
[0025]
(Other Embodiments etc.) Although the present invention has been described above by the
specific embodiments, the present invention is not limited to the above embodiments, and the
present invention can be modified without departing from the scope of the present invention. can
do. In the above embodiment, it is assumed that the frequency range in which a person can
perceive sound is divided into n frequency bands, and the multiband equalizer 11 changes the
gain in all these frequency bands. On the other hand, the gain may be changed only in the range
of a specific frequency band designated in advance. For example, when the present reproduction
sound adjustment device is mounted on a car, it is possible to change the gain only in the range
of a specific frequency band according to the characteristics of the siren sound (warning sound)
of an ambulance. According to this device, when the ambulance siren sounds while playing
music, the sound quality of the music being played is adjusted according to the siren sound, so
that the driver may easily notice the siren sound it can. In addition, a predetermined input unit
and a setting unit may be provided, and the setting unit may set the range of the specific
frequency band based on the user's input accepted by the input unit.
[0026]
In the above embodiment, the reproduction sound adjustment device has the speaker 12 that
outputs the reproduction sound whose gain is changed in a part of the frequency band, but this
reproduction sound is output from the headphone or the earphone It is also good. In this case,
when the microphone 14 is provided on the back side (the opposite side to the ear) of the
headphone or earphone, the ambient sound picked up by the microphone 14 may not be mixed
with the reproduced sound output from the headphone or the like. rare. In addition, the
microphone 14 does not pick up the playback sound from the speaker 12, that is, the ambient
sound does not include the playback sound as much as possible (for example, the distance from
the television at a viewing distance of the television is about 2 to 3 m Can be set as the
conversation area, and the directivity of the microphone 14, the arrangement of the speaker 12
and the microphone 14, and the like can be set. Also in these cases, it is effective to use a
function representing the difference between the intensity of the ambient sound and the intensity
of the reproduced sound as the characteristic comparison function B (f) in the above equation (1).
08-05-2019
12
Furthermore, for example, as terms to be added to the characteristic comparison function B (f),
based on the output characteristic of the speaker, the input characteristic of the microphone, the
acoustic characteristic of the room to be heard, and the characteristic of the sound generated by
the vibration of the reproduction sound adjustment device May be set. More detailed setting of
correction parameters can be performed by the additional terms based on these characteristics.
[0027]
In the first embodiment, the frequency characteristic comparison unit 16 increases or decreases
the gain of the reproduced sound according to the difference between the intensity of the
ambient sound and the intensity of the reproduced sound, and according to the intensity of the
ambient sound according to the second embodiment. Frequency band (the above-mentioned
frequency band BW (k)) was specified. Using an intensity of the ambient sound and an intensity
of the reproduced sound by another method, that is, constructing an arbitrary function from the
intensity of the ambient sound and the intensity of the reproduced sound, and specifying the
frequency band based on the characteristics of this function it can. The function for identifying
this frequency band may be a function similar to the correction parameter or may be a different
function.
[0028]
In the above embodiment, as shown in FIG. 4, the correction parameter setting unit 17 smoothly
reduces the gain of the reproduced sound by a predetermined gain in the frequency band where
the intensity of the ambient sound is maximized. Correction parameters were set. On the other
hand, in order to simplify the control, the correction parameter setting unit 17 may set the
correction parameter so that the gain of the reproduced sound becomes zero in this frequency
band.
[0029]
It is a block diagram showing composition of a reproduction sound adjustment device as a 1st
embodiment of the present invention. FIG. 7 is a diagram for explaining the operation of the
frequency band identification unit 16 and the correction parameter setting unit 17; FIG. 8 is a
diagram for describing the details of processing in the frequency band identification unit 16; FIG.
7 is a diagram for describing setting of correction parameters for the adjacent frequency band by
08-05-2019
13
the correction parameter setting unit 17. It is a figure for demonstrating the detail of the process
in the frequency band identification part 16 in the reproduction | regeneration sound adjustment
apparatus of 2nd Embodiment.
Explanation of sign
[0030]
DESCRIPTION OF SYMBOLS 1 ... reproduction sound adjustment apparatus 11 ... multiband
equalizer 12 ... speaker 13 ... Fourier-transform processing part (reproduction sound
characteristic acquisition means) 14 ... microphone (ambient sound detection means) 15 ...
Fourier transform processing unit (ambient sound characteristic acquisition means) 16 ...
frequency band identification unit 17 ... correction parameter setting unit
08-05-2019
14
Документ
Категория
Без категории
Просмотров
0
Размер файла
26 Кб
Теги
jp2008228198
1/--страниц
Пожаловаться на содержимое документа