JP2006145818A - Audio signal adjusting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an output sound of characteristics more comfortable to a user. <P>SOLUTION: The audio signal adjusting device 10 which adjusts and outputs an input audio signal is equipped with: a level decision section 12 which decides the input level being the level of the input audio signal; an input/output characteristic memory section 16 which memorizes the level input and output ratio set for every input level as input level and input/output characteristics; and a level adjusting section 14 which adjusts the level of the input audio signal based on the input level and input/output characteristics of the audio signal. The input level and input/output characteristics include the characteristics for coping with low audio which are made higher in the level input-to-output ratio of the low input level and the characteristics for coping with nighttime which are made lower in the level input-to-output ratio of the high input level. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an audio signal adjusting device that performs predetermined signal processing on an input audio signal and outputs the processed signal.

  A device that reproduces and outputs sound, such as a DVD player, a television receiver, and an AV amplifier, is equipped with a sound signal adjustment device that performs predetermined signal processing on the sound signal and outputs the sound signal. In such an audio signal adjustment device, the level of the audio signal is not particularly adjusted, and the low level (low volume) audio signal remains low and the high level (high volume) audio signal is high. Often output as is. Thereby, a natural and wide audio output can be obtained.

  However, depending on the environment in which the audio is viewed and the auditory characteristics of the user, problems may arise if the audio is output at the same level as the input audio. For example, when viewing in a quiet environment such as midnight, if a high level sound is output at a high level, it may be annoying to surrounding people. Conversely, in an environment where there is a large amount of environmental noise such as during the daytime, low-level speech cannot be clearly heard. In addition, there is a problem that a user whose auditory characteristics have deteriorated, such as an elderly person, is difficult to hear low-level sound.

  Therefore, Patent Document 1 discloses an audio processing apparatus that performs dynamic range compression on the level of an audio signal for a hearing-impaired user whose auditory characteristics have deteriorated. In this sound processing device, the input sound signal is level-compressed so that the output sound is within a dynamic range that can be heard. According to such a technique, since the low-level sound is output at a relatively high level, it is possible to hear the low-level sound clearly even when the environmental noise is large or even an elderly user.

JP 2000-22473 A

  However, level dynamic range compression affects not only low level speech but also high level speech. Therefore, a high level audio signal is adjusted to a relatively low level and output. However, it can be said that high-level sound such as explosive sound in a movie is more suitable if it is output as it is at a high level. Also, when level dynamic range compression is performed, the overall width of the output sound is reduced, resulting in a so-called “flat” output sound, which is undesirable.

  Therefore, an object of the present invention is to provide an audio signal adjustment device that can provide output audio with more comfortable characteristics for the user.

  An audio signal adjustment device of the present invention is an audio signal adjustment device that adjusts and outputs an input audio signal, and includes a level determination unit that determines an input level that is a level of the input audio signal, and an input level. Input / output characteristic storage means for storing the level input / output ratio set to the level of the input audio signal based on the input level of the audio signal and the level input / output ratio stored in the input / output characteristic storage means Level adjusting means for adjusting.

  In a preferred embodiment, the level input / output ratios stored in the input / output characteristic storage means are all the same value for the level input / output ratios corresponding to input levels other than the specific attention level. Furthermore, it is desirable to have correction means for correcting between the two audio signals so that the level change between the audio signal of the attention level and the audio signal other than the attention level becomes slow.

  In another preferred aspect, the apparatus further comprises frequency classification means for classifying the input audio signal into a plurality of frequency bands, and the level input / output ratio stored in the input / output characteristic storage means is different for each frequency band and input level. Is set. In another preferred aspect, the apparatus includes a scene determination unit that determines whether or not the input audio signal is an audio signal related to conversation, and performs level adjustment by the level adjustment unit only for the audio signal related to conversation.

  In another preferred aspect, the input / output characteristic storage means has a low input level corresponding to the low input level and a low input level corresponding to the other input level, and a high input level. The level input / output ratio corresponding to the night frequency, and the level input / output ratio corresponding to the high frequency band is reduced to the level input / output ratio corresponding to the other input levels. The hearing aid compatible input / output ratio and at least one level input / output ratio of the larger are stored. Preferably, the input / output characteristic storage means stores and stores at least two or more level input / output ratios of a low-voice compatible input / output ratio, a night-compatible input / output ratio, and a hearing aid compatible input / output ratio. The user can select the type of level input / output ratio used for level adjustment among the plurality of level input / output ratios. In another preferred embodiment, the user can set the level input / output ratio value stored in the input / output characteristic storage means.

  According to the present invention, since the level input / output ratio can be set for each level of the input audio signal, only the level input / output ratio of a specific input level can be increased or decreased according to the viewing environment and the auditory characteristics of the user. . As a result, an output sound with more comfortable characteristics for the user can be obtained.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a configuration of an audio signal adjustment device 10 which is a basic embodiment of the present invention. The audio signal adjusting device 10 is a device mounted on a device that reproduces and outputs an audio signal, such as a DVD player, a television receiver, or an AV amplifier, and adjusts the level of the input audio signal Ain to output audio. Output as Aout. The input audio signal Ain is input to the level determination unit 12, and the level (volume) is determined. The level determination unit 12 passes the input audio signal Ain to the level adjustment unit 14 together with the level determination result. The level adjustment unit 14 performs level adjustment based on the level of the input audio signal Ain, and outputs it as the output audio signal Aout. The level adjustment is performed based on the input / output characteristics stored in the input / output characteristics storage unit 16.

  FIG. 2 is a diagram illustrating an example of the input / output characteristics stored in the input / output characteristic storage unit 16. Here, an example in which the input / output characteristics are stored as a table of the input audio signal level (input level) and the output audio signal level (output level) is shown. The level adjustment unit 14 adjusts the level of the input sound based on the input / output characteristics. For example, when the level of the input audio signal is 12 dB, level adjustment is performed so that the level of the output audio signal is 28 dB. When the input level is 48 dB, the level is adjusted so that the output level is 48 dB. In the present embodiment, the input / output characteristics are stored as a table, but naturally, other forms such as a graph or a mathematical expression may be stored.

  Here, as is apparent from FIG. 2, in this embodiment, the level input / output ratio differs depending on the input level. That is, when the input level is low (less than 36 dB), the level input / output ratio is large, and when the input level is high (36 dB or more), the level input / output ratio is small. The reason for the input / output characteristics will be described with reference to FIG. FIG. 3 is a diagram illustrating several types of input / output characteristics, in which the horizontal axis indicates the input level and the vertical axis indicates the output level. A broken line indicates a general input / output characteristic that has been frequently used, a dashed-dotted line indicates an input / output characteristic when dynamic range compression processing is performed, and a solid line indicates an input / output characteristic in the present embodiment.

  Many conventional general audio signal adjustment devices do not adjust the level of the audio signal. Therefore, the level of the output sound is the same as the input level, and the level input / output ratio is constant regardless of the magnitude of the input level (see the broken line in FIG. 3). Therefore, a low level (small volume) audio signal is output at a low level, and a high level (large volume) audio signal is output at a high level. By outputting the audio signal as it is at the same level as the input level in this way, it is possible to obtain a wide natural output sound inherent in the input audio signal. However, depending on the environment in which the output sound is heard (viewing environment) and the auditory characteristics of the user, it may not be desirable at the same level as the input level. For example, there is a problem that when the environmental noise in the viewing environment is large, it is difficult to hear low-level sound. Conversely, in an environment where the surroundings are quiet, such as at midnight, if a high-level audio signal is output at a high level, it may cause noise and annoy the neighborhood. Also, elderly users and the like have poor hearing characteristics and are difficult to hear low-level sounds.

  Therefore, conventionally, a method has been proposed in which dynamic range compression is performed on an audio signal to adjust a low-level audio signal to a relatively high level and a high-level audio signal to a relatively low level (FIG. 3). See the dash-dot line). According to such a technique, an originally low level audio signal is also output at a level that is easy to hear. As a result, even a user whose auditory characteristics have deteriorated can clearly hear the voice. Further, even when the environmental noise is large, low level speech can be heard clearly. However, with this method, not only low-level audio signals but also all level band audio signals are affected. For example, a powerful high-level audio signal can be output at a relatively low level only by listening at a high volume. In addition, the overall width of the level is reduced, resulting in a so-called “flat” sound.

  Therefore, in this embodiment, the level input / output ratio can be set for each input level, the level input / output ratio of the input level desired to be emphasized is large, and the level input / output ratio of the input level desired to be weakened can be reduced. In the illustrated example of FIG. 2, the level input / output ratio of the low input level (less than 36 dB) is increased, and the level input / output ratio of the other input levels (above 36 dB) is normally set to make it easy to hear low level audio signals. Is set to the same value as By adopting such a setting, it is possible to clearly hear low-level sound even when the environmental noise is large or the auditory characteristics are degraded due to aging. On the other hand, since the high level sound is output at a high level, a natural and powerful output sound can be obtained. Thereby, a more comfortable acoustic characteristic can be provided to the user.

  FIG. 4 is a diagram illustrating a result of adjusting the audio signal based on the input / output characteristics illustrated in FIG. The horizontal axis indicates time, and the vertical axis indicates level. A broken line indicates the level of the input sound, and a solid line indicates the level of the output sound. Usually, the input sound has various levels, and naturally, the sound of low level (less than 36 dB) is also included. In this case, if it is output at the same level, it becomes difficult to hear low-level sound. Therefore, in this embodiment, the level adjustment is performed so that the low-level audio signal is relatively high based on the input / output characteristics illustrated in FIG. As a result, the sound that was originally at a low level becomes a relatively high level, and a low-level sound such as a whisper can be clearly heard. Further, since high-level sound is output at a high level, for example, explosion sound in a movie is output without losing its power.

  As described above, according to the present embodiment, the level input / output ratio can be set for each input level. Therefore, it is possible to output a sound of an input level that is desired to be emphasized at a relatively high level without losing a natural sound width, and to output a sound of an input level that is desired to be weakened at a relatively low level. Thereby, the user can obtain an appropriate output sound according to his / her auditory characteristics and environment.

  In addition, in order to obtain a more natural sound connection, it may be corrected between audio signals having different level input / output ratios. FIG. 5 is a diagram illustrating correction between audio signals having different level input / output ratios. In FIG. 5, the horizontal axis represents time, and the vertical axis represents level. Also, the broken line indicates the input sound, the solid line indicates the output sound whose level is adjusted based on the input characteristics of FIG. 2, and the thick solid line indicates the output sound obtained by correcting the output sound after the level adjustment. Further, points indicated by squares or circles indicate sampling points of the audio signal. In the example of FIG. 5, since the audio signal after P2 is less than 36 dB, the level is adjusted at a higher level input / output ratio than usual (see the solid line in FIG. 5). On the other hand, the audio signal before P1 is adjusted with a normal level input / output ratio. When an audio signal level-adjusted at this high level input / output ratio (audio signal after P2) and an audio signal level-adjusted at the normal level input / output ratio (audio signal before P1) are continued as they are Often, the connection of sound becomes unnatural. Therefore, P2 whose level is adjusted at a higher level input / output ratio than usual and P3 which is three points before this P2 are connected by a straight line and connected. By doing in this way, the connection of the sound between the audio signals having different level input / output ratios approaches a natural shape, and more preferable acoustic characteristics can be obtained. Note that the correction method illustrated here is an example, and naturally, other correction methods may be used for correction. In some cases, the audio signal may be subjected to level adjustment based on the input / output characteristics without correction and output.

  In addition, FIG. 2 illustrates an input / output characteristic having a high level input / output ratio with respect to a low-level input signal as an example of the input / output characteristic. However, if the level input / output ratio is set for each input level, FIG. Of course, other input / output characteristics may be used. For example, input / output characteristics as shown in FIGS. 6A to 6C may be used.

  In addition, the input / output characteristics may be appropriately set by the user. For example, the audio signal adjustment apparatus 10 is provided with some display means, and the input / output characteristic diagram as shown in FIG. 3 is displayed on the display means. Then, the user may be able to set desired input / output characteristics by operating an operation means such as a switch while viewing the displayed input / output characteristics diagram. As another method, several types of input / output characteristics, such as a low voice level response characteristic with only a low level level input / output ratio increased, and a night response characteristic with only a high level level input / output ratio decreased are prepared. In addition, the user may be able to select a desired input / output characteristic according to the situation.

  Furthermore, in this embodiment, the level input / output ratio is set for each input level, but the level input / output ratio may be set for each frequency band. That is, as shown in FIGS. 8 to 10, for each of a plurality of frequency bands, a level input / output ratio is set for each input level, and the level is adjusted with a level input / output ratio corresponding to the frequency and level of the input sound. Also good. For example, in the case of FIG. 8, even if the input signal is the same 12 dB, the input signal with a frequency of 1 kHz is adjusted to 30 dB and the input signal with a frequency of 5 kHz is adjusted to a level of 12 dB and output.

  Thus, by adjusting the level in consideration of the frequency, more appropriate acoustic characteristics can be obtained. For example, in the case of a movie, there are voices related to human speech and voices related to BGM and sound effects even with the same low level voice. At this time, if the voice and sound effects are output at the same level, the voice may be canceled by the sound effects and the voice may not be heard clearly. In such a case, it is desirable to set the level input / output ratio so that only a low-level audio signal having a frequency corresponding to a human voice can be output at a relatively high level.

  Next, a more specific embodiment will be described with reference to FIG. FIG. 7 shows a signal conditioner 20 which is a more specific embodiment of the present invention. This signal adjustment device 20 is mounted on an AV device such as a DVD player or a television, and performs predetermined signal processing on the input audio signal and video signal, and then outputs them. Since a conventional technique can be used for the form of signal processing for a video signal, description thereof is omitted here. In the following, signal processing for audio signals will be mainly described in detail.

  The audio signal input from the external device 22 is input to the encoder 28 via a DIR (digital interface receiver) 26 or an AD converter 24 (hereinafter referred to as “ADC 24”). The DIR 26 is an input interface for digital signals, and accepts input of digital audio signals. The AD converter 24 is an input interface for an analog signal, and converts the analog input signal into a digital signal.

  The encoder 28 encodes the input signal and then outputs it to the digital signal processor 30 (hereinafter referred to as “DSP 30”). The DSP 30 is a processor for performing various signal processing on the digital signal, and functions as a level determination unit, a frequency classification unit, a level adjustment unit, and a correction unit. That is, the DSP 30 determines the level after classifying the input audio signal for each frequency band, and performs level adjustment according to the determination result. Further, correction is performed so that the sound connection after level adjustment becomes natural. Level adjustment is performed based on the input / output characteristics stored in the memory 32. The input / output characteristics will be described in detail later.

  The audio signal subjected to the level adjustment and correction is output to the external device 50 or the speaker 52. The external device 50 corresponds to a video / audio output device such as a television receiver. A speaker attached to the external device 50 corresponds to the speaker 52.

  When the external device 50 can handle a digital signal, the level-adjusted audio signal is output via a DIT (digital interface transmission) 44. The DIT 44 is an output interface for digital signals. On the other hand, when the external device 50 cannot handle a digital signal, or when outputting an audio signal to the speaker 52, the audio signal whose level has been adjusted is decoded by the decoder 40. Further, it is converted into an analog signal by a DA converter 42 (hereinafter referred to as “DAC 42”) and output. At that time, amplification by the electronic volume 46 and the power amplifier 48 is performed as necessary. The electronic volume 46 is an IC that amplifies an analog signal, and the amplification factor can be digitally controlled.

  The OSD (On Screen Display) controller 36 is a processor that creates and outputs a setting screen for setting various setting values. The OSD controller 36 creates various setting screens, for example, input / output characteristic setting screens to be described later, and outputs them to the external device 50. The external device 50 displays the output setting screen on the display. The user sets various setting values while looking at the setting screen displayed on the display. The setting is performed via the remote controller 54 or the like, and the operation content is received as an operation signal by the remote control light receiving unit 56. The received operation signal is output to the CPU 34, and the CPU 34 corrects the setting value stored in the memory 32 according to the operation signal, and instructs the OSD controller 36 to correct the setting screen displayed on the display.

  The CPU 34 is a processor that controls the entire signal conditioning apparatus, and appropriately outputs control signals to the DSP 30 and the OSD controller 36. The CPU 34 also determines the type of scene (scene) related to the signal based on the input audio signal, video signal, or the like. Usually, a program such as a movie is composed of many scenes. Among these scenes, there are conversation scenes in which characters talk and scenes composed only of video and BGM. The CPU 34 determines whether or not the input signal is a signal related to a conversation scene. This determination can be made by frequency analysis or the like of the input audio signal. In the case of a movie, whether or not it is a conversation scene can be determined by the presence or absence of subtitle information. The determination result is output to the DSP 30.

  Such scene type determination is performed because level adjustment may be performed only in the case of a specific scene. For example, in a movie, when it is desired to clearly hear a quiet conversation among the conversations of characters, it is only necessary to adjust the level of the audio signal related to the conversation scene. Conversely, in a scene where the characters do not have a conversation and only BGM and sound effects are flowing, level adjustment is not necessary. Therefore, the CPU 34 determines the scene type, and the DSP 30 determines whether or not to adjust the level according to the result.

  Next, the input / output characteristics stored in the memory 32 will be described. The memory 32 stores normal input / output characteristics with a constant level input / output ratio regardless of the input level and frequency, user-defined input / output characteristics that are user-defined input / output characteristics, and preset fixed input / output characteristics. Has been.

  The normal input / output characteristics are input / output characteristics in which the level input / output ratio is always constant regardless of the level and frequency of the input signal. When the user does not instruct level adjustment, level adjustment is performed based on the normal input / output characteristics.

  The fixed input / output characteristic is an input / output characteristic prepared in advance. In the present embodiment, three types of standard input / output characteristics are prepared: a low voice response characteristic shown in FIG. 8, a night response characteristic shown in FIG. 9, and a hearing aid response characteristic shown in FIG. 8 to 10 are diagrams showing input / output characteristics, wherein the X axis (left and right direction in the drawing) indicates the frequency, the Y axis (diagonal left and right direction in the drawing) indicates the input level, and the Z axis indicates the output level. ing. The user can select an input / output characteristic to be applied from among these three types of fixed input / output characteristics as required. When one of the fixed input / output characteristics is selected by the user, the level of the audio signal is adjusted based on the fixed input / output characteristic.

  The low voice response characteristic shown in FIG. 8 is an input / output characteristic suitable for clearly listening to a low voice even when the environmental noise is large. Therefore, the level input / output ratio when the input level is low (less than 36 dB) and the frequency corresponding to the human voice (200 Hz to 2 kHz) is higher than the level input / output ratio in other cases. When the level is adjusted based on this low voice response characteristic, audio signals other than a specific frequency (200 Hz to 2 kHz) such as BGM and sound effects, and an audio signal having a predetermined frequency or higher even at a specific frequency are input to the normal level. The level is adjusted by the output ratio. In other words, for these sounds, a high level signal is output at a high level and a low level signal is output at a low level. On the other hand, an input signal having a specific frequency (200 Hz to 2 kHz) and less than a predetermined level (36 dB) is adjusted to a relatively high level and output. As a result, even when environmental noise, sound effects, and the like are large, it is possible to clearly hear a low-volume conversation and to enjoy a comfortable appreciation.

  When this low voice response characteristic is selected, a scene-limited mode in which level adjustment is performed only in the case of a conversation scene is set. In the scene-limited mode, the level adjustment with the low voice characteristic is performed only for the audio signal related to the conversation scene. For audio signals related to scenes other than the conversation scene, level adjustment is performed using normal input / output characteristics. In this way, by adjusting the level with the low voice characteristic only for the voice related to the conversation scene, it is possible to clearly hear the voice conversation and to hear other sounds at a natural level. . As a result, suitable acoustic characteristics can be provided. Also, the amount of complicated signal processing can be reduced by performing level adjustment based on the frequency and level only in the case of a specific scene.

  The night correspondence characteristic shown in FIG. 9 is an input / output characteristic suitable for viewing in a quiet environment such as at night without disturbing the surroundings. In this nighttime response characteristic, the level input / output ratio of the input signal having a low frequency (500 Hz or less) and a high level (greater than 96 dB), which has a large influence on the surroundings, is set lower than usual. When the level adjustment is performed based on the nighttime response characteristic, the high-level input sound among the low-frequency, so-called deep bass input signals is relatively adjusted to the low level and output. As a result, the volume of the heavy bass that has a large influence on the surroundings is reduced, so that troubles to the surroundings can be reduced even when viewed in a quiet environment such as at night.

  The hearing aid compatibility characteristics shown in FIG. 10 are input / output characteristics suitable for users who have deteriorated auditory characteristics, for example, elderly people, who want to appreciate comfortably. The elderly and the like have poor auditory characteristics, making it difficult to hear low-level sounds. In particular, it becomes difficult to hear high-frequency sound. Therefore, this hearing aid response characteristic is generally subjected to dynamic range compression, and the level input / output ratio of high frequency (1 kHz or more) and medium / low level is made higher than usual. Thereby, even an elderly person whose auditory characteristics have deteriorated can clearly hear the voice.

  The user-defined input / output characteristics are output characteristics defined by the user. When setting the user-defined input / output characteristics, the user operates the remote controller 54 to instruct display of a setting screen. The CPU 34 and the OSD controller 36 display an input / output characteristic setting screen on the display in accordance with an instruction from the user. Although various forms are conceivable as the setting screen, for example, a three-dimensional graph composed of a frequency axis, an input level axis, and an output level axis as shown in FIGS. 8 to 10 may be displayed. The user may instruct correction of the level input / output ratio of the desired frequency and input level while looking at the displayed three-dimensional graph.

  Next, the flow of audio signal level adjustment in this signal adjustment apparatus will be described with reference to FIG. Prior to reproduction of the audio signal, the user selects input / output characteristics to be applied in advance. Specifically, the user first selects normal input / output characteristics (constant input / output ratio), regular input / output characteristics, or user-defined input / output characteristics. When the standard input / output characteristic is selected, one of a low voice response characteristic, a night response characteristic, and a hearing aid response characteristic is further selected. Here, when the low voice response characteristic is selected, a “scene-limited mode” is automatically set in which the low voice response characteristic is applied only to the voice related to the conversation scene.

  When a user-defined input / output characteristic is selected, a desired level input / output ratio is set while looking at the setting screen. The set input / output characteristic value is stored in the memory 32 as a user-defined input / output characteristic.

  The audio signal input to the signal conditioner 20 is input to the DSP 30 via the DIR 26 (or ADC 24) and the encoder 28. In response to an instruction from the CPU 34, the DSP 30 performs predetermined signal processing on the audio signal. Level adjustment is included as one of the signal processing.

  The DSP 30 refers to the memory 32 and confirms whether or not the normal input / output characteristic is selected (S10). If the normal input / output characteristic is selected, level adjustment is performed based on the normal input / output characteristic (S22). In this normal input / output characteristic, since the level input / output ratio is constant regardless of the input level and frequency, the frequency classification of the input signal and the level determination are not performed. The DSP 30 adjusts the level with a predetermined level input / output ratio, and then outputs an audio signal.

  On the other hand, if the normal input / output characteristics are not selected, it is next determined whether or not the scene limited mode is set (S12). This can be determined by the type of the selected input / output characteristic. If the selected input / output characteristic is a low voice characteristic, it is automatically determined that the scene-limited mode is set. In other cases, it is determined that the scene limited mode is not set.

  If the scene limited mode is set, it is determined whether or not the input voice is applied to the conversation scene (S14). This can be determined based on the result of frequency analysis for the input sound, the presence or absence of caption information, and the like. If it is not a conversation scene, the level is adjusted with the normal input / output characteristics (S22).

  If the scene limited mode is not set, or if the scene limited mode is set and the scene is a conversation scene, the input voice is classified by frequency (S16). Subsequently, the level of the audio signal classified by frequency is determined (S18). Based on these determination results and the set input / output characteristics, level adjustment of the input sound is executed (S20).

  The audio signal subjected to level adjustment is output from the DSP 30 after other necessary signal processing. The output audio signal is output to the external device 50 or the speaker 52 via the decoder 40, DIT 44, DAC 42, or the like. Since the output sound is adjusted to an appropriate level according to the viewing environment and the user's auditory characteristics, the user can enjoy viewing comfortably.

  As described above, in the present embodiment, the level adjustment is performed with the level input / output ratio set for each input level, so that it is possible to obtain an output sound of an appropriate level according to the viewing environment and the user's auditory characteristics. it can. As a result, the user can enjoy comfortable viewing.

It is a block diagram which shows the structure of the audio | voice signal adjustment apparatus which is fundamental embodiment of this invention. It is a figure which shows an example of the input / output characteristic memorize | stored in the input / output characteristic memory | storage part. It is a graph which shows multiple types of input / output characteristics. It is a figure which shows the result of having adjusted the level based on the input-output characteristic of FIG. It is a figure which shows the correction | amendment between audio | voice signals. It is a figure which shows the example of another input-output characteristic. It is a block diagram which shows the structure of the signal adjustment apparatus which is other embodiment of this invention. It is a figure which shows a low voice response characteristic. It is a figure which shows the night correspondence characteristic. It is a figure which shows a hearing aid correspondence characteristic. It is a flowchart which shows the flow of the level adjustment with respect to an audio | voice signal.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Audio | voice signal adjustment apparatus, 12 level determination part, 14 level adjustment part, 16 input-output characteristic memory | storage part, 20 signal adjustment apparatus, 22, 50 external apparatus, 30 DSP, 36 OSD controller, 52 speaker.

Claims (8)

An audio signal adjustment device that adjusts and outputs an input audio signal,
Level determining means for determining an input level which is a level of an input audio signal;
Input / output characteristic storage means for storing a level input / output ratio set for each input level;
Level adjustment means for adjusting the level of the input audio signal based on the input level of the audio signal and the level input / output ratio stored in the input / output characteristic storage means;
An audio signal adjustment device comprising: The audio signal adjustment device according to claim 1,
An audio signal adjusting apparatus characterized in that the level input / output ratios stored in the input / output characteristic storage means are all the same value for the level input / output ratios corresponding to input levels other than a specific level of interest. The audio signal adjustment device according to claim 2, further comprising:
An audio signal adjusting apparatus comprising: a correcting unit that corrects between two audio signals so that a level change between an audio signal of an attention level and an audio signal other than the attention level becomes slow. The audio signal adjustment device according to any one of claims 1 to 3, further comprising:
A frequency separation means for separating the input audio signal into a plurality of frequency bands;
The audio signal adjustment apparatus, wherein the level input / output ratio stored in the input / output characteristic storage means is set for each frequency band and input level. The audio signal adjustment device according to any one of claims 1 to 4, further comprising:
Scene determination means for determining whether or not the input audio signal is an audio signal related to conversation,
An audio signal adjusting apparatus characterized by performing level adjustment by a level adjusting means only for an audio signal related to a conversation. The audio signal adjustment device according to claim 1,
The input / output characteristic storage means is
The low-level input / output ratio corresponding to the low input level is larger than the level input / output ratio corresponding to other input levels,
I / O ratio for nighttime, with the level I / O ratio corresponding to the high input level smaller than the level I / O ratio corresponding to other input levels,
Hearing-aid compatible input / output ratio with a level input / output ratio corresponding to the high frequency band greater than the level input / output ratio in other frequency bands,
An audio signal adjustment device, wherein at least one level input / output ratio is stored. The audio signal adjustment device according to claim 6,
The input / output characteristic storage means stores at least two or more level input / output ratios of a low-voice compatible input / output ratio, a night-compatible input / output ratio, and a hearing aid compatible input / output ratio,
An audio signal adjusting apparatus, wherein a user can select a type of level input / output ratio used for level adjustment among a plurality of stored level input / output ratios. The audio signal adjustment device according to any one of claims 1 to 7, further comprising:
An audio signal adjusting device characterized in that a user can set a level input / output ratio value stored in an input / output characteristic storage means.

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