JP2008233920A - Sound reproducing device and sound reproducing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an optimum reproduced sound based upon sound characteristics of a listening room etc., and sound characteristics of a music source. <P>SOLUTION: Sound characteristics of audio data are determined by analyzing metadata retrieved from a database, and sound characteristics when the audio data are reproduced are adjusted based upon the sound characteristics of the audio data and in-room sound characteristics in a reproduction sound field space. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an acoustic reproduction method suitable for reproducing a music source recorded in, for example, a concert hall in a listening room, and an acoustic reproduction apparatus capable of reproduction by such an acoustic reproduction method.

The acoustic characteristics of the listening room vary depending on the size, shape, and interior condition of the listening room. For this reason, there is a sound reproducing apparatus that corrects the acoustic characteristics of the listening room so as to be close to the standard acoustic characteristics or the listener's favorite acoustic characteristics.
In such a sound reproducing device, for example, a measurement signal for measuring acoustic characteristics is radiated in a listening room, and a response (reflected sound) is collected to calculate the room acoustic characteristics of the listening room. Then, there is a technique in which a correction characteristic for correcting the acoustic characteristic in the listening room is calculated from the calculated room acoustic characteristic, and the reproduction signal is corrected by the calculated correction characteristic (Patent Document 1).

In order to measure room acoustic characteristics such as a listening room, it is necessary to obtain a transfer function from a sound source position to a listening position. In the case of a listening room, the sound source position is the speaker position of the sound reproducing device.
For example, in the intensity stereo system, two speakers arranged on the front left and right are sound source positions. Further, for example, in the 5.1 channel system, there are two speakers arranged at the front left and right, one speaker at the front center, and two speakers arranged at the rear left and right, and these five speakers are sound sources. Become position. Thus, when the speaker is the sound source position, the measurement is performed for each channel speaker. The transfer function when all the channels are driven can be obtained by calculating the sum of the transfer functions of the respective channels.

  As the measurement microphone installed at the listening position, the directivity characteristic is the same as that of the listener, or a proximity four-point method microphone capable of searching the sound source position is used (Non-Patent Document 1).

  A microphone with the same characteristics as the listener's directional characteristics is a dummy head microphone. As a simplified microphone, on both sides corresponding to human ears on the surface of a spheroid made to resemble the head. Some have a microphone embedded.

  In addition, a method has been proposed in which information on installation and characteristic adjustment of an audio system is acquired via a network, and the audio system automatically adjusts the characteristic accordingly.

  For example, a service system is constructed by a center server and an audio system connected to the center server via a communication network. The center server transmits audio device adjustment data and audio device attachment data to the audio system.

Meanwhile, the audio system automatically adjusts the acoustic characteristics using the received audio device adjustment data. Also, there is an audio system that displays received attachment data of an audio device, and a user attaches the audio device to a vehicle based on the displayed attachment method (Patent Document 2).
Note that there is Non-Patent Document 2 regarding the interaural correlation coefficient in a diffuse sound field.

JP-A-6-327089 JP 2002-67815 A Acoustic measurement of a concert hall by the proximity four-point method, Yoshio Yamazaki, Atsushi Ito, JAS Journal October 1987 issue Interaural correlation coefficient in diffuse and reproduced sound field, Mikio Higashiyama, et al., Acoustical Society of Japan Acoustical Society, H-84-28, 1984

  However, there are various music sources that the listener listens to in the listening room, and the required acoustic characteristics differ depending on the genre and how the reflected sound and reverberation sound of the concert hall are recorded. For this reason, conventional sound reproducing apparatuses have a drawback that the user needs to perform troublesome work such as adjusting the acoustic characteristics every time the music source is replaced in consideration of the genre of the music source and the recording environment. .

  Therefore, the present invention has been made in view of the above points, and an acoustic reproduction method capable of realizing optimal acoustic characteristics based on acoustic characteristics such as a listening room and acoustic characteristics of a music source. An object is to provide a sound reproducing device.

To achieve the above object, an audio reproducing method of the present invention determines the acoustic characteristics of the audio data by analyzing the meta data retrieved from the database, the acoustic characteristics of the audio data, room acoustics of the reproduction sound field space Based on the characteristics, the acoustic characteristics when reproducing the audio data are adjusted.

The sound reproducing apparatus of the present invention includes an audio data reproducing unit that reproduces audio data, a content identification code detecting unit that detects a content identification code from the audio data, and a content identification code from a database based on the content identification code. Database search means for reading out the metadata corresponding to the voice data analysis means for analyzing the metadata searched from the database by the database search means and determining the acoustic characteristics of the voice data reproduced by the voice data reproduction means, Based on the acoustic characteristic measuring means for measuring the room acoustic characteristics of the reproduction sound field space, the room acoustic characteristics measured by the acoustic characteristic measuring means, and the acoustic characteristics acquired by the voice data analyzing means, Acoustic characteristics adjustment to adjust the acoustic characteristics during playback And so it comprises a stage, a.

  According to the present invention as described above, it is possible to adjust the acoustic characteristics when reproducing the audio data based on the acoustic characteristics of the audio data to be reproduced and the acoustic characteristics of the reproduction sound field space.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to adjust the acoustic characteristic at the time of reproducing | regenerating audio | voice data according to the acoustic characteristic of a listening room and the acoustic characteristic at the time of recording the audio | voice data of the music source which should be reproduced | regenerated. Therefore, even when music sources with different recording environments and genres are played on the sound playback device, the user can automatically adjust the sound characteristics suitable for the music source and play without adjusting the sound characteristics. become.

Embodiments of the present invention will be described below.
In the present embodiment, for example, on the recording medium such as an optical disc, the metadata indicating the nature of the space in which the audio data is to be reproduced together with the audio data recorded by the on-microphone that does not include reflected sound and reverberation sound. Is recorded.

First, the sound reproducing apparatus according to the present embodiment will be described with reference to FIGS.
FIG. 1 is a block diagram showing a configuration of a sound reproducing apparatus according to the present embodiment.
In FIG. 1, an audio data reproduction unit 2 performs reproduction processing such as reading audio data recorded on a recording medium (not shown) and decoding the read audio data.

  The metadata analysis unit 3 acquires the metadata recorded on the recording medium via the audio data reproduction unit 2. Then, the acquired metadata is analyzed to determine the acoustic characteristics of the listening room which is a reproduction sound field space suitable for reproducing the audio data of the recording medium. The nature of the reproduction sound field space recorded as metadata on the recording medium can be shown as shown in FIG.

The nature of the reproduced sound field space is indicated by reverb. As shown in FIG. 2B, the reverb is indicated by the original sound (direct sound), the initial reflected sound, and the reverberation sound of the reverb body.
For this reason, the parameters indicating the properties of the reproduced sound field space and their scales (definitions) can be shown as shown in FIG.

For example, the rate reverbrance is indicated by the reverberation time length from the direct sound to the reverb body, and the value is, for example, 1.4 to 2.8 (sec).
Liveness is indicated by the reverberation time length of a high tone, and the numerical value is, for example, 1.5 to 2.2 (sec).
The source presence is indicated by the ratio of the direct sound and the initial reflected sound, and for example, the numerical value is −2 to 2 (dB).
Warmth is indicated by a ratio between a low-frequency initial reflection sound and a high-frequency initial reflection sound, and the numerical value is, for example, 1.2 to 1.25 (dB).
The room presence is indicated by the level of the reverberant sound, for example, the value is -0.5 to 0.5 (dB).
The running reverbrance is indicated by the reverberation time length of the initial reflected sound, and the numerical value is, for example, 1.8 to 2.6 (sec).
The envelope is indicated by the ratio of the initial reflected sound to the direct sound. For example, the numerical value is 0.1 to 0.3 (%).

  The acoustic characteristic data storage unit 4 is configured by a memory, for example, and stores acoustic characteristic data analyzed by the metadata analysis unit 3.

  The changeover switch 5 is a switch for selecting the acoustic characteristic data of the audio data supplied to the reproduction characteristic control unit 6, and is output from the acoustic characteristic data once stored in the acoustic characteristic data storage unit 4 or the metadata analysis unit 3. One of the acoustic characteristic data is selected.

The reproduction characteristic adjusting unit 7 adjusts the acoustic characteristic of the audio data reproduced by the audio data reproducing unit 2 based on the control of the reproduction characteristic control unit 6.
The reproduction characteristic control unit 6 includes acoustic characteristic data input from the metadata analysis unit 3 or the acoustic characteristic data storage unit 4 via the changeover switch 5 and room acoustic characteristic data of the listening room input via the changeover switch 18. Based on the above, the reproduction characteristic adjusting unit 7 is controlled. A method for acquiring the acoustic characteristic data of the listening room will be described later.

  The changeover switch 8 is a switch for supplying either the measurement data of the room acoustic characteristic measurement data storage unit 19 or the voice data of the voice data reproduction unit 2 to the room acoustic characteristic analysis unit 16.

  The changeover switch 9 supplies either the audio data from the reproduction characteristic adjustment unit 7 or the acoustic characteristic measurement data from the acoustic characteristic measurement data storage unit 19 described later to the subsequent D / A conversion unit 10. Switch.

  The D / A converter 10 converts a digital signal (data or acoustic characteristic measurement data) input via the changeover switch 9 into an analog signal (audio signal or acoustic characteristic measurement signal) and outputs the analog signal.

  The power amplifier 11 amplifies the analog signal from the D / A converter 10 to a predetermined level, and the speaker system 12 outputs the signal amplified by the power amplifier 11 as an audible sound.

For example, when measuring the room acoustic characteristics of a listening room, the microphone system 13 is arranged at a predetermined listening point (listening position) and picks up sound at that position.
The microphone amplifying unit 14 amplifies and outputs a collected sound signal obtained by collecting sound by the microphone system 13.
The A / D converter 15 converts the analog sound pickup signal from the microphone amplifier 14 into a digital sound pickup signal and outputs it.

The room acoustic characteristic analysis unit 16 analyzes the collected sound data input via the A / D conversion unit 15 by using the input signal input via the changeover switch 8 as a reference signal, thereby analyzing the room acoustics of the listening room. To get the characteristics.
The room acoustic characteristic data storage unit 17 is configured by a memory, for example, and stores the room acoustic characteristic data obtained by the room acoustic characteristic analysis unit 16.

  The changeover switch 18 is a switch for selecting the acoustic characteristic data of the listening room to be supplied to the reproduction characteristic control unit 6. As the acoustic characteristic data, the acoustic characteristic data once stored in the room acoustic characteristic data storage unit 17 or the room acoustics Any of the acoustic characteristic data directly output from the characteristic analysis unit 16 is supplied.

  The room acoustic characteristic measurement data storage unit 19 stores measurement data for measuring room acoustic characteristics such as a listening room. Such measurement data may be an M-sequence signal (Maximum Length Sequence), a TSP (Time Stretched Pulse) signal, or the like.

  Note that such control of the entire sound reproduction device 1 and switching control of the change-over switches 5, 8, 9, 18 are performed by a system controller (not shown).

  In the sound reproducing apparatus 1 configured as described above, the sound characteristics of the sound data are adjusted based on the sound characteristics obtained from the metadata recorded on the recording medium and the room acoustic characteristics of the actual listening room. I am doing so. For this reason, in the sound reproducing device 1, the metadata analysis unit 3 is provided as an acoustic characteristic acquisition unit that acquires the acoustic characteristic of the audio data, and an acoustic characteristic measurement unit for measuring the room acoustic characteristic of the listening room. Is provided.

FIGS. 3A and 3B are diagrams showing the configuration of the acoustic characteristic measuring means provided in the above-described acoustic reproduction apparatus 1. FIG.
FIG. 3A is a diagram illustrating a configuration of an acoustic characteristic measuring unit using the room acoustic characteristic measurement data storage unit 19. In this case, sound source data suitable for the measurement item is selected and read from the room acoustic characteristic measurement data storage unit 19. Then, the read measurement data is transmitted to the D / A converter 10 via the changeover switch 9, D / A converted by the D / A converter 10, then amplified by the power amplifier 11, and the amplified measurement signal is obtained. Output from the speaker system 12 is performed.

The output sound of the speaker system 12 is picked up by the microphone of the microphone system 13 installed at a predetermined measurement point in the listening room.
Then, the sound collection signal output from the microphone of the microphone system 13 is amplified by the microphone amplification unit 14, and the amplified sound collection signal is A / D converted by the A / D conversion unit 15. To be transmitted.

In this case, the room acoustic characteristic analysis unit 16 analyzes the sound collection data using the measurement data input from the room acoustic characteristic measurement data storage unit 19 via the changeover switch 8 as reference data, thereby obtaining the acoustic characteristic of the listening room. (Transfer function) is obtained.
The analysis result of the room acoustic characteristic analysis unit 16 is stored in the room acoustic characteristic data storage unit 17.

  Here, the reason why the room acoustic characteristic analysis unit 16 obtains the transfer function of the listening room using the measurement data in the room acoustic characteristic measurement data storage unit 19 as reference data is as follows.

  Basically, if the measurement sound signal output from the speaker system 12 is an impulse signal and the response is collected by the microphone system 13, the collected sound signal of the microphone system 13 becomes a transfer function of the listening room. In the method, it is difficult to increase the S / N. For this reason, in the present embodiment, a signal having large energy is used as measurement data, and the sound collection data (response signal) input via the A / D converter 15 is changed over by the switch 8 in the room acoustic characteristic analysis unit 16. The transfer function of the listening room is calculated by dividing by the measurement data input via the.

Further, according to Non-Patent Document 2, it is possible to determine whether the sound field has a natural diffusibility by analyzing the correlation coefficient of two omnidirectional microphones arranged at an equivalent binaural distance (about 30 cm). It is supposed to be. Therefore, for example, if the reproduction characteristic is changed in some ways and the correlation coefficient at the listening position at that time is measured, the room acoustic characteristic analysis unit 16 can obtain the room acoustic characteristic data under a condition close to a natural diffuse sound field. It will be.
The room acoustic characteristic measurement data generated from the room acoustic characteristic measurement data storage unit 19 may be generated each time by an arithmetic means such as a DSP (Digital Signal Processor).

On the other hand, FIG. 3B is a diagram showing the configuration of the acoustic characteristic measurement means when the room acoustic characteristic measurement data storage unit 19 is not used.
In this case, the audio data reproduced by the audio data reproducing unit 2 is used as measurement data. That is, after the audio data reproduced by the audio data reproduction unit 2 is transmitted to the D / A conversion unit 10 via the reproduction characteristic adjustment unit 7 and the changeover switch 9, and after D / A conversion by the D / A conversion unit 10, Amplified by the power amplifier 11 and the amplified audio signal is output from the speaker system 12.

  Also in this case, the output sound of the speaker system 12 is collected by the microphone of the microphone system 13. Then, the sound collection signal output from the microphone of the microphone system 13 is amplified by the microphone amplification unit 14, and the amplified sound collection signal is A / D converted by the A / D conversion unit 15. To transmit.

The room acoustic characteristic analysis unit 16 uses the audio data or the like input from the audio data reproduction unit 2 via the changeover switch 8 to perform analysis according to the measurement measurement item, thereby listening as a reproduction sound field space. The acoustic characteristics (transfer function) of the room are obtained.
The analysis result of the room acoustic characteristic analysis unit 16 is stored in the room acoustic characteristic data storage unit 17. In this case as well, a transfer function is obtained by dividing the collected sound data (response signal) by the audio data (input signal). In addition, the room acoustic characteristic data storage unit 17 can store the room acoustic characteristics of a typical listening room in advance.

In the sound reproducing device 1 of the present embodiment configured as described above, the room acoustic characteristics of the listening room are measured, and the acoustic characteristics of the measured listening room and the sound of the metadata recorded on the recording medium are measured. Based on the characteristic, the reproduction characteristic adjustment unit 7 adjusts the acoustic characteristic of the audio data reproduced from the audio data reproduction unit 2.
In this way, in the sound reproducing apparatus 1 according to the present embodiment, when the sound signal is reproduced according to the room sound characteristic of the listening room and the sound characteristic when the sound signal of the music source to be reproduced is recorded. The acoustic characteristics can be adjusted.
As a result, even when a music source having a different recording environment or genre is played in the sound playback apparatus 1, the user can automatically adjust to the sound characteristics suitable for the music source without playing back the sound characteristics. Is possible.

Here, the acoustic characteristics that the listening room affects the sound image will be described.
The listening room structure that affects the acoustic characteristics includes, for example, left-right asymmetry of the acoustic space. An example of such a listening room is shown in FIG.
In the listening room 20 shown in FIG. 4, the right wall 21R has higher sound absorption than the left wall 21L of the listener U, and there is almost no reflected sound from the right wall 21R. That is, the state of reflection is greatly different between the left wall surface 21L and the right wall surface 21R.

  In this case, a sound that reaches the listener U from the left speaker 12L disposed on the left front side of the listener U and a sound that reaches the listener U from the right speaker 12R disposed on the right front side of the listener U. In comparison, the direct sounds SDL and SDR reaching the listener U from the speakers 12L and 12R are substantially the same, but the reflected sounds SRL and SRR reflected by the left and right wall surfaces 21L and 21R are greatly different. As a result, the sound image 22 of vocals and main musical instruments that should be localized at the substantially central position of the left and right speakers 12L and 12R may be shifted in the direction in which the reflected sound is loud (in the left direction in this case) or from a specific direction. The sound image of the listening room 20 may be affected, for example, only the sound of the sound is noticeable.

Therefore, in the sound reproducing device 1 of the present embodiment, the reproduction characteristic adjusting unit 7 is configured as shown in FIG. 5 to adjust the audio data.
The reproduction characteristic adjusting unit 7 shown in FIG. 5 includes a pseudo reflected sound adding circuit 23 and an inter-channel level difference adjusting circuit 24. When there is almost no reflected sound from the right wall surface 21R of the listening room 20, the right speaker After the pseudo reflected sound data is added to the sound data output from 12R by the pseudo reflected sound adding circuit 23, the level difference between the left and right channels is adjusted and output by the inter-channel level difference adjusting circuit 24. .
With this configuration, even when there is almost no reflected sound SRR from the right wall surface 21R of the listening room 20, the sound image 22 such as vocals is located at substantially the center position of the left and right speakers 12L and 12R by the pseudo reflected sound SRR1 from the right speaker 12R. Can be localized.

  Further, a pseudo reverberation sound adding circuit 25 for adding pseudo reverberation sound data as indicated by a broken line is provided to the reproduction characteristic adjusting unit 7 so that the pseudo reverberation sound is added to the reproduction sound of the right speaker 12R. The sound image 22 such as vocals can be localized more naturally.

The reproduction characteristic adjusting unit 7 can also be configured as shown in FIG.
The reproduction characteristic adjusting unit 7 shown in FIG. 6 includes a canceling filter 51 and a pseudo reflected sound adding circuit 23. The canceling filter 51 cancels reproduced sounds from the left and right speakers 12L and 12R in the listening room 20. , After the SCR, an acoustic characteristic such as a desired reflected sound is added. That is, after applying reverse characteristics so that the characteristics from the speakers 12L and 12R to the listening position become flat frequency characteristics, the pseudo reflected sound adding circuit 23 adds the acoustic characteristics of the desired reflected sound.

  With this configuration, even if there is almost no reflected sound SRR from the right wall surface 21R of the listening room 20, the left and right speakers 12L, 12L, The sound image 22 such as a vocal having a feeling of spreading at a substantially central position of 12R can be localized.

  Also in this case, a pseudo reverberation sound adding circuit 25 for adding pseudo reverberation sound data as shown by a broken line is provided to the reproduction characteristic adjusting unit 7 so that the reproduction sound output from the left and right speakers 12L, 12R is provided. If a pseudo reverberation sound is added, the sound image 22 can be localized more naturally.

Here, the canceling filter 51 as described above will be described with reference to FIG.
In FIG. 7, the head diffraction transfer function of the path from the left speaker 67 to the left ear EL of the listener U in the reproduced sound field space 69 is HLS, and the path of the path from the right speaker 68 to the right ear ER of the listener U is shown. The head diffraction transfer function is HRS. The head diffraction transfer function of the path from the left speaker 67 to the right ear ER of the listener U is HLO, and the head diffraction transfer function of the path from the right speaker 68 to the left ear EL of the listener U is HRO.

  In the canceling filter 51 shown in FIG. 7, a left collected sound signal SLin is input as a left channel signal and a right collected signal SRin is input as a right channel signal from a dummy head microphone not shown in the figure.

  The left collected sound signal SLin, which is the left channel signal, is input to the adder 61 and the crosstalk cancel unit 62. The right sound pickup signal SRin, which is the right channel signal, is input to the adder 64 and the crosstalk canceling unit 63.

  The crosstalk cancellation units 62 and 63 cancel the crosstalk talk component from the left speaker 67 to the right ear ER of the listener U and the crosstalk talk component from the right speaker 68 to the left ear EL of the listener U, respectively. It is considered as a filter.

In this case, the transfer characteristic CR of the crosstalk cancel unit 62 is indicated as -HRO / HRS. The transfer characteristic CL of the crosstalk canceling unit 63 is indicated as -HLO / HLS.
Then, the left collected sound signal SLin that has passed through the crosstalk canceling unit 62 is input to the adder 64 as a cancel signal. Further, a cancel signal is input to the adder 61 for the right sound pickup signal SRin that has passed through the crosstalk canceling unit 63.

The adder 61 adds the input left sound pickup signal SLin and the cancel signal from the crosstalk cancel unit 63 and outputs the result. The output of the adder 61 is supplied to the correction block unit 65.
The adder 64 adds the input right sound pickup signal SRin and the cancel signal from the crosstalk cancel unit 62 and supplies the sum to the correction block unit 66.

  The correction block unit 65 is a block unit for correcting a reproduction system including the left speaker 67 for the left channel. The correction block unit 65a corrects a change in characteristics caused by the crosstalk cancellation unit 63 and a speaker characteristic. It is comprised by the speaker correction | amendment part 65b to correct. Such a transfer characteristic of the correction unit 65a is expressed as 1 / (1-CL · CR). The transfer characteristic of the correction unit 65b is indicated as 1 / HLS. The output of the correction block unit 65 is output from the canceling filter 60 as a left sound collection signal SLout.

  The correction block unit 66 is a block unit for correcting a reproduction system including the right speaker 68 for the right channel, and a correction unit 66a for correcting a change in characteristics caused by the crosstalk cancellation unit 62, and speaker characteristics. Is constituted by a speaker correction unit 66b for correcting the above. Such a transfer characteristic of the correction unit 66a is represented by 1 / (1-CL · CR). The transfer characteristic of the correction unit 66b is indicated as 1 / HRS. The output of the correction block unit 66 is output from the canceling filter 60 as a right sound pickup signal SRout.

  Then, the left sound collection signal SLout output from the canceling filter 60 is input to the left speaker 67 of the reproduction sound field space 69, and the right sound collection signal SRout is input to the right speaker 68 of the reproduction sound field space 69. Then, only the left ear sound corresponding to the left sound collection signal SLin input to the canceling filter 60 can be reproduced for the left ear EL of the listener U in the reproduction sound field space. Similarly, only the right ear sound corresponding to the right sound pickup signal SRin input to the canceling filter 60 can be reproduced on the right ear ER of the listener U.

By the way, although the sound reproducing apparatus 1 according to the above-described embodiment has been described on the assumption that the metadata indicating the property of the target space where the sound data is to be reproduced is recorded together with the sound data of the recording medium. Such metadata is not necessarily recorded on a recording medium.
For example, it is possible to record a content identification code on a recording medium and record metadata corresponding to the content identification code in a database on the network.

  Therefore, next, as another configuration of the sound reproducing device of the present embodiment, sound suitable for a case where metadata corresponding to a content identification code recorded on a recording medium is recorded in a database on a network or the like. The playback device will be described.

FIG. 8 is a block diagram showing the configuration of such a sound reproducing device.
In addition, the same number is attached | subjected to the same site | part as the sound reproduction apparatus 1 shown in FIG. 1, and description is abbreviate | omitted.
In FIG. 8, the content identification code detector 31 detects the content identification code recorded on the recording medium from the audio data output from the audio data reproducing unit 2.

The database search unit 32 reads metadata corresponding to the content identification code from the database based on the content identification code detected by the content identification code detection unit 31.
For example, the database search unit 32 reads the corresponding metadata from the database storage unit 33 when the content identification code is already stored in the database storage unit 33 in the sound reproduction device 30 together with the metadata. The

  On the other hand, if not yet stored in the database storage unit 33, the network access unit 34 is controlled to read the metadata corresponding to the content identification code from the database on the network 35, and the metadata together with the content identification code. The data is stored in the database storage unit 33.

  The audio data analysis unit 36 analyzes the metadata searched from the database by the database search unit 32 to determine the acoustic characteristics of the listening room suitable for reproducing the audio data of the recording medium.

  Also in such a sound reproducing device 30, the sound characteristics of the reproduced sound data can be adjusted based on the room sound characteristics of the listening room 20 and the metadata corresponding to the sound data recorded on the recording medium. Therefore, as described above, even when music sources having different recording environments and genres are reproduced in the listening room, it is possible to automatically adjust and reproduce the sound characteristics suitable for the music source.

  Note that the content identification code for identifying audio data or the like recorded on the recording medium does not have to be recorded for identifying the content. For example, the TOC data of the compact disc or the music signal data It is also possible to use a content identification code that has a very low probability of having the same combination of numerical values, such as a part.

FIG. 9 is a block diagram showing still another configuration of the sound reproducing device according to the present embodiment. In addition, the same number is attached | subjected to the same site | part as the sound reproduction apparatus shown in FIG.1 and FIG.8, and description is abbreviate | omitted.
In the sound reproducing device 40 shown in FIG. 9, the sound data analyzing unit 36 performs the performance of the sound data reproduced by the sound data reproducing unit 2 and the sound space in which the sound data is recorded or the sound data. The analysis of the room acoustic characteristics of the wax virtual acoustic space is performed.

For example, the timing and magnitude of the reflected sound are analyzed from the shape of the autocorrelation function of the audio signal and the shape of the cepstrum, and analysis such as sound image spread is performed from the cross-correlation function between channels.
At this time, it is preferable that the audio data analysis unit 36 is provided with a band division filter function so that the structure of the reflected sound can be analyzed by dividing into frequency bands when the audio data is analyzed.

  The analysis result of the audio data analysis unit 36 may be stored in the audio characteristic data storage unit 4 for each content identification code, for example, and called up every time a content is selected.

  Also in such a sound reproducing device 40, the sound characteristics of the reproduced sound data are adjusted based on the room sound characteristics of the listening room 20 and the sound characteristics of the sound data obtained from the sound data recorded on the recording medium. Therefore, as described above, even when a music source having a different recording environment or genre is played in the listening room, it is possible to automatically adjust the sound characteristics suitable for the music source and play it.

  Note that the configuration of the sound reproduction device described so far is merely an example, and the sound characteristics are adjusted based on the sound characteristics of the reproduction data to be reproduced from the recording medium and the room sound characteristics of the listening room. Any playback device can be used.

  In the present embodiment, the recording medium is described as an optical disc. However, this is merely an example, and for example, a Blu-Ray disc, a CD (Compact Disc) disc, and a Mini Disc. Various types of memory cards such as HDDs (hard disk drives) or memory cards such as flash memories are possible.

It is the block diagram which showed the structure of the sound reproduction apparatus made into embodiment of this invention. It is the figure which showed the parameter which shows the property of the reproduction | regeneration sound field space recorded on a recording medium as metadata. It is the figure which showed the structure of the acoustic characteristic measurement means provided in the sound reproduction apparatus made into this Embodiment. It is the figure which showed an example of the listening room. It is the figure which showed the structural example of the reproduction | regeneration characteristic adjustment part. It is the figure which showed the other structural example of the reproduction | regeneration characteristic adjustment part. It is the figure which showed the structural example of the canceling filter. It is the block diagram which showed the other structure of the sound reproducing device made into this Embodiment. It is the block diagram which showed the further another structure of the sound reproduction apparatus made into this Embodiment.

Explanation of symbols

  1 30 40 sound reproduction device, 2 audio data reproduction unit, 3 metadata analysis unit, 4 acoustic characteristic data storage unit, 5 8 9 18 changeover switch, 6 reproduction characteristic control unit, 7 reproduction characteristic adjustment unit, 10 D / A conversion 11, power amplification unit, 12 speaker system, 13 microphone system, 14 microphone amplification unit, 15 A / D conversion unit, 16 room acoustic characteristic analysis unit, 17 room acoustic characteristic storage unit, 19 room acoustic characteristic measurement data storage unit, 20 listening room, 23 pseudo reflected sound adding circuit, 24 inter-channel level difference adjusting circuit, 25 pseudo reverberation adding circuit, 31 content identification code detecting unit, 32 database searching unit, 33 database storage unit, 34 network access unit, 35 Network, 36 voice data analysis unit, 51 cancel Ring filter

Claims (7)

Audio data reproducing means for reproducing audio data;
Content identification code detection means for detecting a content identification code from the audio data;
Database search means for reading out metadata corresponding to the content identification code from the database based on the content identification code;
Audio data analysis means for analyzing the metadata retrieved from the database by the database search means and determining acoustic characteristics of the audio data reproduced by the audio data reproduction means;
Acoustic characteristic measuring means for measuring room acoustic characteristics of the reproduction sound field space;
An acoustic characteristic adjusting unit that adjusts an acoustic characteristic when reproducing the audio data based on the room acoustic characteristic measured by the acoustic characteristic measuring unit and the acoustic characteristic acquired by the audio data analyzing unit;
Sound reproducing apparatus Ru equipped with. The database search means is
Sound reproducing apparatus according to claim 1, characterized in that to obtain the above SL metadata via the network. The voice data analyzing means is
The metadata retrieved from the database by the database retrieval unit is analyzed, and the acoustic characteristic of the acoustic space in which the voice data reproduced by the voice data reproduction unit is recorded is used as the acoustic characteristic of the voice data. 2. The sound reproducing device according to 2. The acoustic characteristic measuring means includes
The room acoustic characteristic calculation means for calculating the room acoustic characteristic of the reproduction sound field space based on the reproduction sound reproduced by the sound data reproduction means for the reproduction sound field space. sound reproducing apparatus according to 1. The acoustic characteristic acquisition means is
The sound reproducing apparatus according to claim 1 , wherein the acoustic characteristics are obtained from a recording medium on which the audio data is recorded. The acoustic characteristic acquisition means is
The sound reproducing apparatus according to claim 1, wherein the sound characteristics are acquired via a network. Analyzing the metadata retrieved from the database to determine the acoustic characteristics of the audio data,
The acoustic characteristics of the audio data, based on the room acoustic characteristic of the reproduced sound field space, row cormorants sound reproducing method to adjust the acoustic characteristics at the time of reproducing the audio data.

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