JP2017034526A - On-vehicle information apparatus and navigation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an on-vehicle information apparatus and navigation device, capable of achieving an audio output in which the magnitude of sound is heard to the same degree before interruption sound is generated and while an interruption sound is being generated.SOLUTION: Volume levels of input audio signals A1, A2 are increased or decreased so that loudness values which are an index of sound which a human can actually hear by the ear are the same between input audio signals A1, A2 and output audio signals B1, B2 formed by superimposing guide sound signals C upon another.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an in-vehicle information device and a navigation device capable of listening to an audio voice and an interrupt voice signal such as a route guidance voice.

  Conventionally, when outputting audio sound, it has been necessary to interrupt another sound at an appropriate volume. For example, the device described in Patent Document 1 outputs an interrupted sound at a volume level equal to or higher than a certain value even if the volume of the amplifier is equal to or smaller than a certain value. When the volume of the amplifier is equal to or greater than a certain value, the volume level of the interrupt sound is increased in proportion to the volume. Japanese Patent Laid-Open No. 2004-228561 limits the audio signal level with the upper limit even when the user operates the operation unit to increase the volume during guidance voice output, and limits the guidance voice level with the lower limit even when the volume is lowered. An audio device is described.

JP 2004-320582 A JP 2000-161977 A

In the apparatus described in Patent Document 1, the volume level of the interrupted sound can be adjusted in a range of a certain value or more according to the volume of the amplifier.
However, since the recording level of the audio signal is not taken into consideration, there is a problem that the interrupting sound is output at an excessively high volume relative to the audio sound, or conversely, the volume of the audio sound is large and it becomes difficult to hear the interrupting sound. there were.

  For example, when the recording level of the audio signal when it is recorded in the audio source is low, if the volume is increased in order to make the audio sound easy to hear, the interrupt sound may be output at a very large volume. In this case, a loud sound is suddenly output every time an interrupt sound is generated, which is not preferable.

  In addition, when the recording level of the audio signal is high, even if the volume level of the interrupt sound is a certain value or more, it becomes difficult to hear the interrupt sound due to the audio sound. In this case, even if the user operates the volume to make it easier to hear the interrupted sound, the volume of both increases, so the situation where the interrupted sound is difficult to hear is not improved and is inconvenient.

In the audio device described in Patent Document 2, the audio signal level is limited to the upper limit even when the volume is maximized, and the guidance voice level is limited to the lower limit even when the volume is minimized. I'm trying to hear the sound at a moderate volume.
However, even in the audio device described in Patent Document 2, as in the device described in Patent Document 1, since the recording level of the audio signal is not considered, there is a difference between the volume of the audio sound and the volume of the guidance sound. There was a problem that it was difficult to hear one of them.

  For example, when the recording level of the audio signal is high, the audio sound may be output at a volume higher than that of the guidance sound. Further, when the recording level of the audio signal is low, there is a possibility that the audio sound is output at an extremely lower volume than the guidance sound.

The present invention solves the above-described problem. Even when an interrupt sound is generated during sound output, the sound can be felt to have the same volume level before the interrupt sound is generated and during the interrupt sound is generated. It aims at obtaining the vehicle-mounted information apparatus and navigation apparatus which can implement | achieve output.
It is another object of the present invention to provide an in-vehicle information device and a navigation device capable of realizing a sound output in which the sound that has been heard so far during the generation of the interrupt sound and the interrupt sound can be felt at the same volume level.

  The in-vehicle information device according to the present invention includes a first detection unit, a second detection unit, a first comparison unit, and a first level adjustment unit. The first detection unit detects the loudness value of the input sound signal input from the source. The second detection unit detects a loudness value of a signal obtained by adding the interrupt sound signal to the output sound signal generated based on the input sound signal. The first comparison unit compares the output value of the first detection unit with the output value of the second detection unit. The first level adjustment unit is configured to adjust the volume level of the input sound signal based on the comparison result of the first comparison unit so that the output value of the first detection unit and the output value of the second detection unit are the same. Increase or decrease.

  The in-vehicle information device according to the present invention includes a third detection unit, a second comparison unit, and a second level adjustment unit. The third detection unit detects the loudness value of the interrupt sound signal. The second comparison unit compares the output value of the first detection unit with the output value of the third detection unit. Based on the comparison result of the second comparison unit, the second level adjustment unit sets the volume level of the interrupt sound signal so that the output value of the first detection unit and the output value of the third detection unit are the same. Increase or decrease.

  According to the present invention, the loudness value, which is an indicator of the loudness (noisy) of sound actually felt by the human ear, is calculated based on the loudness value of the input sound signal and the output sound signal generated based on the input sound signal. The volume level of the input sound signal is increased or decreased so as to be the same as the loudness value of the signal obtained by adding the interrupt sound signal. As a result, even if an interrupt sound is generated during sound output, it is possible to realize sound output that can be felt at the same volume level before the interrupt sound is generated and during the interrupt sound is generated.

  Further, according to the present invention, the volume level of the interrupt sound signal is increased or decreased so that the loudness value of the input sound signal and the loudness value of the interrupt sound signal are the same. As a result, it is possible to realize a sound output in which the sound that has been heard so far during the generation of the interrupt sound and the interrupt sound can be felt at the same level.

It is a block diagram which shows the structure of the navigation apparatus which concerns on Embodiment 1 of this invention. 3 is a block diagram illustrating a functional configuration of the navigation device according to Embodiment 1. FIG. 4 is a graph showing volume levels and loudness values of input audio signals A1 and A2 and a guidance voice signal C. 6 is a graph showing an example of volume levels and loudness values of input audio signals A1 and A2 and a guidance voice signal C when the volume level of the guidance voice signal C is controlled to be amplified. It is a graph which shows an example of the volume level and loudness value of the guidance audio | voice signal C and output audio signal B1, B2 by which the volume level was amplified when attenuation control of the volume level of input audio signal A1, A2 was not performed. 7 is a graph showing an example of volume levels and loudness values of output audio signals B1 and B2 and guidance voice signal C when attenuation control of volume levels of input audio signals A1 and A2 and guidance voice signal C is performed.

Embodiment 1 FIG.
FIG. 1 is a block diagram showing a configuration of a navigation apparatus 1 according to Embodiment 1 of the present invention. The navigation device 1 is an audio-integrated navigation device that reproduces and outputs an audio signal in addition to navigation processing, and includes a navigation processing unit 2, a system microcomputer 3, an operation unit 4, an adjustment unit 5, an addition unit 6, and power. An amplifier 7 is provided.
The audio signal is input as an input audio signal from the audio source 9, and output from the power amplifier 7 as an output audio signal to the speakers 8a to 8d to output sound. The input audio signal is an embodiment of the input sound signal in the present invention, and the output audio signal is an embodiment of the output sound signal in the present invention.

The navigation processing unit 2 performs navigation processing such as route search, route guidance, and map display based on the current position information and map information.
The guidance voice signal is a signal that becomes a guidance voice that informs the traveling direction of the vehicle on the route obtained by route search, the distance to the guidance point such as an intersection, and the driving operation. This guidance voice is output every time it is generated by the navigation processing unit 2 even if the navigation apparatus 1 outputs the audio voice. Therefore, the guidance voice is an interruption voice for the audio voice that has been output.

The system microcomputer 3 is a microcomputer that controls the operation of the navigation apparatus 1 as an audio device. For example, various adjustment processes in the adjustment unit 5, signal amplification of the power amplifier 7, and switching of the audio source 9 are controlled.
The system microcomputer 3 is a processing circuit that realizes the function of each block, which will be described later with reference to FIG.

  The operation unit 4 accepts user operations such as an audio source 9 selection operation and a volume operation. The adjustment unit 5 is a component that performs various adjustment processes on the input audio signal input from the audio source 9, and is realized as, for example, one function of a DSP (Digital Signal Processor). The adjustment unit 5 includes a volume adjustment unit 5a, a fader adjustment unit 5b, a balance adjustment unit 5c, a sound quality adjustment unit 5d, and an addition unit 6 as functional configurations.

  The volume adjustment unit 5a adjusts the volume level of the input audio signal. The fader adjustment unit 5b performs fader adjustment of the input audio signal. The balance adjustment unit 5c performs left and right balance adjustment of the input audio signal. The sound quality adjustment unit 5d adjusts the sound quality of the input audio signal. The input audio signal input from the audio source 9 is adjusted in the order of the volume adjusting unit 5a, the fader adjusting unit 5b, the balance adjusting unit 5c, and the sound quality adjusting unit 5d, and the input audio signal thus adjusted is adjusted. On the other hand, a guidance voice signal is added as will be described later.

The adder 6 adds the guidance voice signal to the input audio signal adjusted in this way. The power amplifier 7 amplifies the input audio signal that has passed through the adjustment unit 5, and outputs the amplified audio signal as an output audio signal to the speakers 8 a to 8 d to output sound.
The speakers 8a to 8d are speakers mounted on the vehicle. The speaker 8a is a speaker FR installed on the right side of the front part of the vehicle, and the speaker 8b is a speaker FL installed on the left side of the front part of the vehicle. The speaker 8c is a speaker RR installed on the rear right side of the vehicle, and the speaker 8d is a speaker RL installed on the left rear side of the vehicle.

  The audio source 9 embodies the source in the present invention, and includes a reproducing unit and a receiving unit. The reproducing unit reads data recorded on a recording medium such as a CD, DVD, SD, USB memory, HDD, and reproduces an audio signal from the read data. The receiving unit extracts an audio signal from a broadcast signal received from a broadcast station and data received from an external device connected by wire or wireless via the Internet or the like.

  In the audio-integrated navigation device 1 as shown in FIG. 1, when a guidance voice signal is generated during output of a voice based on an audio signal input from the audio source 9, either of the FR channel and FL channel speakers 8a and 8b is selected. Often the guidance voice is interrupted. In this case, conventionally, the audio sound output from the speaker of the channel in which the guidance sound is interrupted is muted, or the guidance is performed by lowering the volume level of the input line of the power amplifier 7 of the FR channel and the FL channel while outputting the guidance sound. The sound was easy to hear.

However, if only the channel that interrupts the guidance voice is set to mute in this way, the localization of the audio output is greatly disturbed, which may give the listener a sense of discomfort.
For example, in the state before the guidance voice is generated, the vocal voice at the time of stereo reproduction is localized at the center between the FR channel speaker 8a and the FL channel speaker 8b. When the channel or FL channel is muted, it seems that the localization position has suddenly moved to the right end or the left end. Then, as soon as the guidance voice ends and the mute setting is canceled, the center position returns.

In the case of an audio signal with a high recording level, when the guidance voice is generated, if the degree of the volume level of the input line of the power amplifier 7 of the FR channel and the FL channel is insufficient, the guidance voice is erased and heard. There is no possibility.
On the other hand, if the volume level of the guidance voice signal is too high, the guidance voice will cancel out the output of the audio signal, giving the listener a sense of discomfort.

Therefore, in the navigation device 1 according to the first embodiment, with respect to the loudness value that is an index of the loudness (noisy) felt by humans, the output audio generated based on the loudness value of the input audio signal and the input audio signal. The volume level of the input audio signal is increased or decreased so that the loudness value of the signal obtained by adding the guidance voice signal to the signal is the same. By doing in this way, the listener feels the sound volume of the same level between the audio sound before the generation of the guidance voice and the voice when the guidance voice is superimposed on this.
Furthermore, by increasing or decreasing the volume level of the guide voice signal so that the loudness value of the input audio signal and the loudness value of the guide voice signal are the same, the audio voice and the guide voice have the same loudness during the generation of the guide voice. I feel it. Thus, the volume operation need not be performed so that the listener can easily hear the guidance voice.

FIG. 2 is a block diagram showing a functional configuration of the navigation apparatus 1. As an example, the sound signal processing in the present invention is applied to the sound of the FL channel and the FR channel. Note that the processing described below may be applied to RL channel and RR channel audio.
As shown in FIG. 2, the navigation device 1 includes an input signal adding unit 10, a loudness detecting unit 11, 12, 17, an output signal adding unit 13, comparison units 14, 18, increase / decrease amount setting units 15, 19, and a level adjusting unit. 16, 20, time constant setting units 21, 22 and an exception control unit 23.
The input signal adding unit 10 adds the input audio signal A1 input from the audio source 9 and the input audio signal A2. The input audio signal A1 and the input audio signal A2 are audio signals to be output from the FL channel and the FR channel, respectively.

  The loudness detector 11 embodies the first detector of the present invention, and detects the loudness value LA of the waveform signal obtained by synthesizing the input audio signals A1 and A2 output from the input signal adder 10. . Here, the volume level of the waveform of the audio signal is detected, and the exponent of the loudness actually felt by the human ear is calculated. This calculation result becomes a loudness value. A method for detecting a loudness value has been proposed. For example, an audio signal is passed through a filter weighted with a frequency band having a higher auditory sensitivity than a frequency band with a low human auditory sensitivity, and a value obtained by integrating and averaging the output signal of this filter at a predetermined sample time is a loudness value. And

The loudness detector 12 embodies the second detector of the present invention, and detects the loudness value LB of the signal output from the output signal adder 13. The detection method of the loudness value is the same as that of the loudness detection unit 11.
The output signal adding unit 13 adds the output audio signal B1 and the output audio signal B2 added with the guidance voice signal C, and outputs a waveform signal obtained by synthesizing these signals.
The output audio signal B1 is an output audio signal A1 ′ whose volume level of the input audio signal A1 has been adjusted by the level adjusting unit 16.
Further, the output audio signal B2 is a guide voice signal C whose volume level is adjusted by a level adjusting unit 20 described later with respect to the output audio signal A2 ′ whose volume level of the input audio signal A2 is adjusted by the level adjusting unit 16. Is a signal obtained by adding.

The comparison unit 14 embodies the first comparison unit in the present invention, and compares the loudness value LA output from the loudness detection unit 11 with the loudness value LB output from the loudness detection unit 12.
Further, the comparison unit 14 calculates a difference between the loudness value LA and the loudness value at that time as a comparison result. The comparison result is output from the comparison unit 14 to the increase / decrease amount setting unit 15.

The increase / decrease amount setting unit 15 determines the increase / decrease amount of the volume level of the input audio signals A <b> 1 and A <b> 2 based on the comparison result of the comparison unit 14 and sets it in the level adjustment unit 16.
For example, the volume levels of the input audio signals A1 and A2 having the same loudness values LA and LB corresponding to whether or not the loudness value LB is larger than the loudness value LA and the difference between the loudness values LA and LB at that time. A table in which the amount of increase or decrease is registered is used.
That is, if the loudness value LB is greater than or equal to the loudness value LA, the increase / decrease amount setting unit 15 refers to the table based on the difference and determines the attenuation level of the volume level of the input audio signals A1 and A2. When the loudness value LB is smaller than the loudness value LA, the increase / decrease amount setting unit 15 refers to the table based on the difference and determines the amount of amplification of the volume level of the input audio signals A1 and A2.

The level adjustment unit 16 embodies the first level adjustment unit of the present invention, and increases or decreases the volume level of the input audio signals A1 and A2 by the increase / decrease amount set by the increase / decrease amount setting unit 15. For example, when the loudness value LB is equal to or greater than the loudness value LA, the input audio signals A1 and A2 are attenuated by an attenuation amount corresponding to the difference, and the volume levels of the input audio signals A1 and A2 are decreased by the same amount. On the other hand, when the loudness value LB is smaller than the loudness value LA, the input audio signals A1 and A2 are amplified by an amplification amount corresponding to the difference, and the volume levels of the input audio signals A1 and A2 are increased by the same amount. .
Thereby, the volume level of the input audio signals A1 and A2 is automatically adjusted so that the volume level of the output audio signal B2 obtained by adding the output audio signal B1 and the guidance voice signal C is the same.

The loudness detection unit 17 embodies the third detection unit of the present invention, and detects the loudness value LC of the guidance voice signal C. The detection method of the loudness value is the same as that of the loudness detection unit 11.
The comparison unit 18 embodies the second comparison unit in the present invention, and compares the output value LA of the loudness detection unit 11 and the output value LC of the loudness detection unit 17. The comparison unit 18 calculates whether or not the loudness value LC is larger than the loudness value LA, and calculates a difference between the loudness values at that time as a comparison result. The comparison result is output from the comparison unit 18 to the increase / decrease amount setting unit 19.

The increase / decrease amount setting unit 19 determines the increase / decrease amount of the volume level of the guidance voice signal C based on the comparison result of the comparison unit 18 and sets it in the level adjustment unit 20.
For example, the volume of the guidance voice signal C in which the loudness value LA and the loudness value LC are the same in association with whether the loudness value LC is larger than the loudness value LA and the difference between the loudness values LA and LC at that time. Use a table in which the level increase / decrease amount is registered.
That is, if the loudness value LC is equal to or greater than the loudness value LA, the increase / decrease amount setting unit 19 refers to the table based on the difference and determines the amount of attenuation of the volume level of the guidance voice signal C. When the loudness value LC is smaller than the loudness value LA, the increase / decrease amount setting unit 19 refers to the table based on the difference and determines the amount of amplification of the volume level of the guidance voice signal C.

The level adjustment unit 20 embodies the second level adjustment unit of the present invention, and increases or decreases the volume level of the guidance voice signal C by the increase / decrease amount set by the increase / decrease amount setting unit 19.
For example, when the loudness value LC is equal to or greater than the loudness value LA, the guidance voice signal C is attenuated by an attenuation amount corresponding to the difference to lower the volume level. On the other hand, when the loudness value LC is smaller than the loudness value LA, the guidance voice signal C is amplified by an amplification amount corresponding to the difference to increase the volume level.
As a result, the volume levels of the input audio signals A1 and A2 and the volume level of the guidance voice signal C are automatically adjusted to be the same.

  Based on the comparison results between the comparison unit 14 and the comparison unit 18, the volume levels of the input audio signals A1 and A2 and the volume level of the guidance voice signal C are increased or decreased. Thus, even when the guidance voice is interrupted during the output of the audio voice, the audio voice and the guidance voice can be heard with the same loudness as when only the audio voice is heard. Furthermore, since the guidance voice is always heard at a loudness value of the same level as the audio voice, it is not difficult to hear either the output of the audio signal or the guidance voice.

The time constant setting unit 21 embodies the first time constant setting unit according to the present invention, and sets the time constant in which the volume levels of the input audio signals A1 and A2 are increased or decreased step by step in the level adjustment unit 16. To do.
For example, when the guidance voice signal C is generated, the level adjustment unit 16 immediately attenuates at the volume levels of the input audio signals A1 and A2 by the attenuation amount set by the increase / decrease amount setting unit 15. As a result, the user feels the same sound volume between the voice output before the guidance voice signal C is generated and the voice output when the guidance voice signal C is being generated.
On the other hand, when the guidance voice signal C ends, the level adjustment unit 16 cancels the attenuation of the input audio signals A1 and A2. At this time, if the volume of the audio sound suddenly increases, the listener may feel uncomfortable.
Therefore, the time constant setting unit 21 sets a time constant at which the volume levels of the input audio signals A1 and A2 are amplified in stages in the level adjustment unit 16. For example, the time constant is amplified stepwise within a range of about 1 second. As a result, the listener hears the audio sound as if it has increased in steps, resulting in a natural volume change.
When it is desired to avoid a sudden decrease in the volume of the audio sound, the time constant setting unit 21 sets a time constant at which the volume level of the input audio signals A1 and A2 is attenuated step by step in the level adjustment unit 16. May be.

The time constant setting unit 22 embodies the second time constant setting unit of the present invention, and sets the time constant for the level adjustment unit 20 to increase or decrease the volume level of the guidance voice signal C stepwise. For example, when the level adjustment unit 20 lowers the volume level of the guidance voice signal C, the level adjustment unit 20 immediately attenuates the volume level of the guidance voice signal C with the attenuation set by the increase / decrease amount setting unit 19. On the other hand, when the volume level of the guidance voice signal C is increased, if the volume of the guidance voice suddenly increases, there is a concern that the listener may feel uncomfortable.
Therefore, the time constant setting unit 22 sets a time constant at which the volume level of the guidance voice signal C is amplified in stages in the level adjustment unit 20. For example, the time constant is amplified stepwise within a range of about 1 second. Thereby, it is heard from the listener that the guidance voice is increased step by step, and the volume changes naturally.
If it is desired to avoid a sudden decrease in the volume of the guidance voice, the time constant setting unit 22 may set a time constant in the level adjustment unit 16 at which the volume level of the guidance voice signal C is attenuated stepwise. Good.

When the loudness value LA output from the loudness detection unit 11 exceeds the upper limit threshold, the exception control unit 23 controls the volume level amplification amount of the guidance voice signal C to the lower limit.
For example, when the recording levels of the input audio signals A1 and A2 are large and the volume of the audio sound is large, if the volume level of the guidance sound signal C is increased accordingly, the guidance sound is also output at a large volume. In this case, the listener may feel uncomfortable.
Therefore, when the volume levels of the input audio signals A1 and A2 exceed the upper threshold, the volume of the guidance voice is prevented from becoming extremely high by controlling the amplification level of the volume level of the guidance voice signal C to the lower limit. .
The lower limit value is, for example, the minimum value of the volume level amplification amount that can be set by the increase / decrease amount setting unit 15. This minimum value is a minimum amplification amount that is an adjustment value of the loudness value LC at which the guidance voice can be heard without any problem even with respect to the assumed maximum loudness value LA.

In addition, when the loudness value LA output from the loudness detection unit 11 is below the lower limit threshold, the exception control unit 23 controls the volume level attenuation of the input audio signals A1 and A2 to the lower limit value. For example, when the recording levels of the input audio signals A1 and A2 are small and the volume of the audio sound is small, the audio signal is very small when the volume level of the input audio signals A1 and A2 is lowered due to the generation of the guidance voice signal C. The sound is output at a volume, which may make it difficult for the listener to hear.
Therefore, when the volume level of the input audio signals A1 and A2 exceeds the lower limit threshold, the output volume of the audio signal does not become extremely small by controlling the attenuation of the volume level of the input audio signals A1 and A2 to the lower limit value. Like that.
The upper limit value is, for example, the minimum value of the volume level attenuation that can be set by the increase / decrease amount setting unit 19. This minimum value is adjusted by adjusting the volume levels of the input audio signals A1 and A2 and adjusting the volume levels of the input audio signals A1 'and A2' with the generation of the guidance voice. Is the minimum amount of attenuation that is attenuated to such an extent that the audio of the input audio signals A1 ′ and A2 ′ cannot be heard.

The input signal adding unit 10, the output signal adding unit 13, and the level adjusting units 16 and 20 are components of the adjusting unit 5 shown in FIG. 1, and are realized as one function of the DSP constituting the adjusting unit 5, for example. be able to. The loudness detection units 11, 12, 17, comparison units 14, 18, increase / decrease amount setting units 15, 19, time constant setting units 21, 22 and exception control unit 23 are realized as functions of the system microcomputer 3 shown in FIG. be able to. For example, the system microcomputer 3 includes a CPU and a memory, and includes an input signal addition unit 10, a loudness detection unit 11, 12, 17, an output signal addition unit 13, comparison units 14, 18, increase / decrease amount setting units 15, 19, The functions of the level adjustment units 16 and 20, the time constant setting units 21 and 22 and the exception control unit 23 are realized by software, firmware, or a combination of software and firmware. Software and firmware are described as programs and stored in a memory.
The function of each unit is realized by the system microcomputer 3 by the CPU reading and executing the program stored in the memory.

Further, although the audio integrated navigation device 1 has been described so far, the present invention is not limited to this. The present invention can be applied to any in-vehicle information device that outputs an interrupt sound signal other than this sound during sound output.
For example, the interruption sound may be a temporarily generated sound such as an e-mail ringing tone or an emergency alert, and the in-vehicle information device may be an audio with a display.
Further, an interrupt sound signal may be output in response to a hands-free call output.

In addition, when making the volume level of interruption sound signals, such as a guidance voice, constant, you may abbreviate | omit the structure which adjusts the volume level of an interruption sound signal.
In this case, the in-vehicle information device according to the present invention only needs to include the loudness detection units 11 and 12, the comparison unit 14, and the level adjustment unit 16. In this case, during the generation of the interrupt sound signal, the input sound signal is automatically adjusted so that the volume level of the input sound signal and the volume level of the output sound signal on which the interrupt sound signal is superimposed are approximately the same. As a result, even if an interrupting sound is generated during the sound output, the listener can feel the same loudness as before.

Next, the operation will be described with a specific example.
FIG. 3 is a graph showing an example of volume levels and loudness values of the input audio signals A1 and A2 and the guidance voice signal C. In FIG. 3, the horizontal axis indicates time, and the vertical axis indicates volume level and loudness value. Assuming that the input audio signals A1 and A2 are the same voice, in this case, both signals are displayed as overlapped as shown in FIG.
The loudness value LA is equal to twice the individual loudness value of the input audio signal A1 or the input audio signal A2 because the same audio values are added.
Since the guidance voice signal C is a voice that interrupts in a short time, the volume level and the loudness value LC are rectangular signals as shown in FIG.

FIG. 4 is a graph showing an example of the volume levels and loudness values of the input audio signals A1 and A2 and the guidance voice signal C when the volume level of the guidance voice signal C is amplified. FIG. 4 shows a result of comparing the loudness value LA and the loudness value LC by the comparison unit 18 and adjusting the volume level of the guidance voice signal C so that the loudness values LA and LC are the same.
Since the loudness value LC of the guidance voice signal C is small, the volume level of the guidance voice signal C is amplified and larger than the volume levels of the input audio signals A1 and A2.
Here, when the recording levels of the input audio signals A1 and A2 are extremely high, if the volume level of the guidance voice signal C is amplified so that the loudness values LA and LC are the same, the guidance voice is output at an extremely high volume. There is a possibility.
Therefore, when the volume level of the input audio signals A1 and A2 exceeds the upper limit threshold, the exception control unit 23 controls the amount of amplification of the volume level of the guidance voice signal C to the lower limit value.
In FIG. 4, it is assumed that the volume levels of the input audio signals A1 and A2 have not reached the upper threshold.

FIG. 5 shows an example of the volume level and the loudness value of the guidance voice signal C and the output audio signals B1 and B2 whose volume levels are amplified when the attenuation control of the volume levels of the input audio signals A1 and A2 is not performed. It is a graph. In FIG. 5, the loudness value LB of the output audio signals B1 and B2 increases only while the guidance voice signal C is being output.
In FIG. 4, the loudness value LA of the input audio signals A1 and A2 and the loudness value LC of the guidance voice signal C are made the same, so the loudness value LA does not become smaller than the loudness value LC.
However, if the volume levels of the input audio signals A1 and A2 are not attenuated, the loudness value LB, which is the sum of the loudness value LA and the loudness value LC, is greater than the loudness value LA as shown in FIG. . As a result, the total volume of the audio voice and the guidance voice is higher than the volume of the audio voice alone, so that a loud sound is suddenly output, giving the listener unpleasant feeling.
Therefore, as shown in FIG. 6, the navigation apparatus 1 according to the first embodiment attenuates the volume levels of the input audio signals A1 and A2 and the volume level of the guidance voice signal C so that the loudness values LA and LB become the same. Control.

FIG. 6 is a graph showing an example of the volume levels and loudness values of the output audio signals B1, B2 and the guidance voice signal C when the volume levels of the input audio signals A1, A2 and the guidance voice signal C are attenuated. It is. In FIG. 6, the loudness value LA and the loudness value LB are compared by the comparison unit 14, the volume levels of the input audio signals A1 and A2 are adjusted so that the loudness values LA and LB are the same, and the loudness value LA and the loudness value are further adjusted. This is a result of comparing LC with the comparison unit 18 and adjusting the volume level of the guidance voice signal C so that the loudness values LA and LC are the same. There is no change in the loudness values LA and LB when the guidance voice signal C is output and when the guidance voice signal C is not output.
Thereby, it is heard from the listener that the volume does not change even if the guidance voice is output during the output of the audio signal.

However, if the loudness value LA of the input audio signals A1 and A2 is extremely small, the output of the audio signal becomes difficult to hear if the amount of attenuation in the time interval in which the guidance voice is output is too large.
Therefore, when the volume levels of the input audio signals A1 and A2 are below the lower limit threshold, the exception control unit 23 controls the attenuation level of the volume levels of the input audio signals A1 and A2 to the lower limit value.

In this way, even if there is a difference in volume level, audio signal recording level, and volume level of audio signals output from the left and right channels, the guidance voice can be heard at an appropriate volume.
In FIGS. 1 and 2, the vehicle is a right-hand drive vehicle, and the guidance voice signal is added to the audio signal of the FR channel so that the guidance voice can be heard only in the FR channel on the driver's seat side. In the case of a left-hand drive vehicle where guidance voice can be heard only through the FL channel on the driver's seat side, the guidance voice signal is added to the FL channel audio signal.
Further, the guide voice signal may be added to the audio signals of the FR channel and the FL channel so that the guide voice is output from both the left and right channels.

  As described above, in the navigation device 1 according to the first embodiment, the loudness value LA based on the input audio signals A1 and A2 and the loudness value LB based on the output audio signals B1 and B2 obtained by adding the guidance voice signal C are the same. Thus, the volume levels of the input audio signals A1 and A2 are increased or decreased. In this way, even if a guidance voice is generated during the output of the audio voice, it is possible to realize a voice output that can be felt at the same volume level as before the guidance voice is generated. At this time, if the loudness value LA based on the input audio signals A1 and A2 and the loudness value LC based on the guidance voice signal C are aligned, the audio voice and the guidance voice can be felt to the same level.

  In addition, the navigation device 1 according to Embodiment 1 increases or decreases the volume level of the guidance voice signal C so that the input audio signals A1 and A2 and the guidance voice signal C have the same loudness value. By doing so, it is possible to realize an audio output in which the audio voice and the guidance voice can be felt at the same volume during the generation of the guidance voice.

Further, in the navigation device 1 according to the first embodiment, the time constant for increasing or decreasing the volume level of the input audio signals A1 and A2 is set in the level adjusting unit 16.
Thereby, it is heard from the listener that the volume of the audio sound is increased or decreased step by step, and the volume changes naturally and does not give a sense of incongruity.

Furthermore, in the navigation device 1 according to the first embodiment, a time constant for increasing or decreasing the volume level of the guidance voice signal C is set in the level adjusting unit 20.
Thereby, it is heard from the listener that the volume of the guidance voice is increased or decreased step by step, and the volume changes naturally and does not give a sense of incongruity.

Furthermore, when the output value of the loudness detection unit 11 exceeds the upper limit threshold, the navigation device 1 according to Embodiment 1 controls the amount of amplification of the volume level of the guidance voice signal C to the lower limit. When the output value of the loudness detection unit 11 falls below the lower limit threshold, the attenuation level of the volume level of the input audio signals A1 and A2 is controlled to the lower limit.
With this configuration, it is possible to prevent the guide voice from becoming extremely loud in adjusting the volume of the guide voice, and to prevent the audio sound volume from becoming extremely small in adjusting the output volume of the audio signal. Thereby, a natural volume change can be realized.

  In the present invention, any component of the embodiment can be modified or any component of the embodiment can be omitted within the scope of the invention.

  DESCRIPTION OF SYMBOLS 1 Navigation apparatus, 2 Navigation processing part, 3 System microcomputer, 4 Operation part, 5 Adjustment part, 5a Volume adjustment part, 5b Fader adjustment part, 5c Balance adjustment part, 5d Sound quality adjustment part, 6 Addition part, 7 Power amplifier, 8a 8d Speaker, 9 audio source, 10 input signal adding unit, 11, 12, 17 loudness detecting unit, 13 output signal adding unit, 14, 18 comparing unit, 15, 19 increase / decrease setting unit, 16, 20 level adjusting unit, 21, 22 Time constant setting part, 23 Exception control part.

Claims (7)

A first detector that detects a loudness value of an input sound signal input from a source;
A second detector for detecting a loudness value of a signal obtained by adding an interrupt sound signal to an output sound signal generated based on the input sound signal;
A first comparison unit that compares the output value of the first detection unit and the output value of the second detection unit;
Based on the comparison result of the first comparison unit, the volume level of the input sound signal is increased or decreased so that the output value of the first detection unit and the output value of the second detection unit become the same. An in-vehicle information device comprising: 1 level adjustment unit. A third detector for detecting a loudness value of the interrupt sound signal;
A second comparison unit that compares the output value of the first detection unit and the output value of the third detection unit;
Based on the comparison result of the second comparison unit, the volume level of the interrupt sound signal is increased or decreased so that the output value of the first detection unit and the output value of the third detection unit become the same. The in-vehicle information device according to claim 1, further comprising two level adjustment units. 3. A first time constant setting unit that sets, in the first level adjustment unit, a time constant by which the volume level of the input sound signal is increased or decreased in stages. In-vehicle information equipment. 3. The in-vehicle information device according to claim 2, further comprising a second time constant setting unit that sets a time constant in which the volume level of the interrupt sound signal is increased or decreased step by step in the second level adjustment unit. . When the output value of the first detection unit exceeds an upper limit threshold, the amount of amplification of the volume level of the interrupt sound signal is controlled to a lower limit value, and when the output value of the first detection unit is lower than the lower limit threshold value, The in-vehicle information device according to claim 2, further comprising an exception control unit that controls an attenuation amount of a volume level of the input sound signal to a lower limit value. A navigation processing unit for performing navigation processing;
A first detector that detects a loudness value of an input sound signal input from a source;
A second detection unit for detecting a loudness value of a signal obtained by adding a guidance voice signal of the navigation processing unit to an output sound signal generated based on the input sound signal;
A first comparison unit that compares the output value of the first detection unit and the output value of the second detection unit;
Based on the comparison result of the first comparison unit, the volume level of the input sound signal is increased or decreased so that the output value of the first detection unit and the output value of the second detection unit become the same. And a level adjusting unit. A third detector for detecting a loudness value of the guidance voice signal;
A second comparison unit that compares the output value of the first detection unit and the output value of the third detection unit;
Based on the comparison result of the second comparison unit, the volume level of the guidance voice signal is increased or decreased so that the output value of the first detection unit and the output value of the third detection unit become the same. The navigation device according to claim 6, further comprising: a level adjustment unit.

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