JP2019134357A - Sound collection reproduction device - Google Patents

Abstract

To provide a sound collection reproduction device which can drastically reduce mistakes of before and after a sound image, and which allows an operator to understand a reproduced sound image outside a vehicle, in addition to visual confirmation.SOLUTION: A sound collection reproduction device includes: three or more microphones 2a-2d placed outside a vehicle and having directivity for collecting the sound outside the vehicle; three or more binaural transducers 5a-5d provided corresponding to the three or more microphones, and converting the sound outside the vehicle, which is collected by a corresponding microphone, into binaural sound of the sound image direction corresponding to the orientation direction of the microphones; a binaural sound synthesis section 6 for synthesizing three or more binaural sounds converted in the three or more binaural transducers and a stereo sound of a sound source; and a signal reproduction section 7 for reproducing the binaural sounds synthesized in the binaural sound synthesis section and the stereo sound of the sound source.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a sound collecting and reproducing apparatus that collects sounds around a vehicle and reproduces the collected sounds in the vehicle.

  In a vehicle such as an automobile, a driver's blind spot occurs in the rear, side, and pillar direction of the vehicle body. In recent years, there is an increasing interest in safety confirmation when driving a vehicle, such as visual recognition of surroundings on a monitor.

  In addition to visually confirming the position of surrounding vehicles when changing lanes during driving, further safety is ensured by using safety confirmation by hearing.

  Japanese Patent Application Laid-Open No. H10-228561 describes a vehicle auditory monitor device. This vehicle auditory monitoring device collects sound (collects sound) using a dummy head microphone microphone provided with left and right microphone microphones having an auricle-like structure on the ceiling of an automobile, thereby obtaining sound outside the vehicle. Is binaural with left and right sounds. By reproducing the recorded sound with the in-vehicle stereo, the driver can grasp the reproduced sound image outside the vehicle in addition to the visual confirmation.

JP 2012-146307 A

  However, when left and right microphones having pinna-like structures are used on a traveling vehicle, wind noise is increased, and wind noise and engine sound of surrounding vehicles are masked, making it difficult to hear outside sounds.

  Even if the vehicle is not moving, if the wind blows, it will be difficult to hear the sound outside the vehicle. In addition, with the left and right microphones alone, an error in the sound image is likely to occur. Furthermore, an auricle-like structure is conspicuous in the appearance of the vehicle, and an increase in vehicle height may be an obstacle to vehicle travel.

  An object of the present invention is to provide a sound collection / reproduction device that can drastically reduce mistakes in the front and rear of a sound image and that allows a driver to grasp a reproduction sound image outside the vehicle in addition to visual confirmation.

  In order to solve the above-described problems, a sound collection / reproduction device according to the present invention is provided outside the vehicle, and is provided corresponding to three or more microphones that collect sound outside the vehicle, and the three or more microphones, Three or more binaural converters for converting outside sound picked up by a corresponding microphone into a binaural sound having a sound image direction corresponding to the direction of the microphone, and three converted by the three or more binaural converters A binaural sound synthesis unit that synthesizes the binaural sound and the stereo sound of the sound source; and a signal reproduction unit that reproduces the binaural sound synthesized by the binaural sound synthesis unit and the stereo sound of the sound source. Features.

  The sound collecting / reproducing apparatus of the present invention is disposed outside the vehicle and behind the vehicle, and is provided corresponding to the one or more microphones that collect the sound outside the vehicle, and the one or more microphones. One or more binaural converters that convert outside-vehicle sound collected in step 1 into a binaural sound having a sound image direction corresponding to the direction of the microphone, and one or more binaural parts converted by the one or more binaural converters A binaural sound synthesizing unit that synthesizes the sound and the stereo sound of the sound source; and a signal reproducing unit that reproduces the binaural sound synthesized by the binaural sound synthesizing unit and the stereo sound of the sound source. .

  The sound collecting / reproducing apparatus of the present invention is arranged outside the vehicle and behind the vehicle, and collects one or more microphones for collecting sounds outside the vehicle, and sounds outside the vehicle and sound source collected by the one or more microphones. A synthesizing unit that synthesizes the stereo sound of the sound source, and one or more that are arranged at the rear of the vehicle corresponding to the one or more microphones, and reproduce the external sound synthesized by the synthesizing unit and the stereo sound of the sound source And a speaker.

  In addition, the directional microphones in all the above-described sound collecting and reproducing apparatuses of the present invention can be replaced with omnidirectional (omnidirectional) microphones having no directional characteristics. When a microphone with no directivity is used, the sound image localization becomes clear by providing a sound absorbing material or a sound absorbing plate between the microphones. Even when no sound absorbing material or sound absorbing plate is provided, sound image localization can be obtained by increasing the distance between the microphones.

  According to the present invention, three or more microphones pick up the outside sound, and three or more binaural converters convert the outside sound picked up by the microphone into a binaural sound in a sound image direction corresponding to the direction of the microphone. Then, the binaural sound synthesizing unit synthesizes three or more binaural sounds and the stereo sound of the sound source, and the signal reproducing unit reproduces the synthesized binaural sound and the stereo sound of the sound source.

  Therefore, three or more microphones can drastically reduce mistakes before and after the sound image, and by reproducing the sound field outside the vehicle with a binaural conversion on the car stereo, the driver can grasp the reproduced sound image outside the vehicle in addition to visual confirmation. .

It is a block diagram of the sound collecting and reproducing apparatus according to the first embodiment of the present invention, and is a diagram showing an example in which four microphones are provided on the left and right sides. It is a figure which shows the perceived azimuth | direction angle with respect to a target azimuth | direction angle when four microphones are provided in the sound collecting / reproducing apparatus based on Example 1 of this invention diagonally right and left. It is a figure which shows the example which provided the three microphones ahead and right and left in the sound collection reproducing | regenerating apparatus based on Example 2 of this invention. It is a figure which shows the example which provided four microphones in right and left front and back in the sound collection reproducing | regenerating apparatus based on Example 3 of this invention. It is a figure which shows the perceived azimuth angle with respect to the target azimuth angle when four microphones are provided on the left and right and front and rear in the sound collecting and reproducing apparatus according to Embodiment 3 of the present invention. It is a figure which shows the example which has arrange | positioned four microphones in the sound collecting / reproducing apparatus which concerns on Example 4 of this invention left and right diagonally back and forth from the center on the ceiling or under the floor. It is a figure which shows the example which provided the four microphones in the four corners of a vehicle. It is a figure which shows arrangement | positioning of the dashboard speaker containing a directional tweeter, a normal door speaker, and a normal rear speaker in the sound collection reproducing | regenerating apparatus based on Example 5 of this invention. It is a figure which shows arrangement | positioning of the normal rear speaker and the door speaker containing a normal dashboard speaker and a narrow directivity tweeter. It is a figure which shows the main structure block diagrams of the sound collection reproducing | regenerating apparatus based on Example 6 of this invention. It is a figure which shows the main structural block diagrams of the sound collection reproducing | regenerating apparatus based on Example 7 of this invention. It is a figure which shows the example which provided the three microphones in right and left and back in the sound collection reproducing | regenerating apparatus based on Example 8 of this invention. It is a figure which shows the example which provided the back microphone in the sound collection reproducing | regenerating apparatus based on Example 9 of this invention. It is a figure which shows the example which has arrange | positioned the sound-absorbing material or the sound-absorbing board between each omnidirectional microphone in the sound collection reproducing | regenerating apparatus based on Example 10 of this invention.

  Hereinafter, a sound collecting and reproducing apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings.

  The sound collecting and reproducing apparatus according to the first embodiment confirms safety by reproducing a sound field outside the automobile with a car stereo using binaural reproduction technology. FIG. 1 is a configuration diagram of a sound collecting / reproducing apparatus according to Embodiment 1 of the present invention, and shows an example in which four microphones are provided obliquely front and rear.

  FIG. 1A shows an arrangement of four microphones 2 a to 2 d provided outside the vehicle 1. The four microphones 2a to 2d are formed of directional microphones, and are arranged at the center of the vehicle ceiling or under the floor diagonally right and left, and collect outside sound. That is, the microphones 2a and 2b are arranged in a 45 ° direction from the front front and the microphones 2c and 2d are arranged in a 45 ° direction from the rear front.

  The microphones 2a to 2d are arranged at 90 ° intervals. The directivity angle of n microphones is ± 180 / n or more. Since n is the number of microphones, and in this example, n is 4, the directivity angles of the microphones 2a to 2d are ± 45 degrees or more.

  FIG.1 (b) shows the azimuth | direction angle which installs microphone 2a-2d. By setting the narrow directivity microphones 2a to 2d (directivity angle is 101 degrees, for example) close to the center of the upper part of the vehicle body, the range of azimuth angles collected by the microphones 2a to 2d is shared. The front of the vehicle 1 is set to 0 degree, and the microphones 2a to 2d are arranged in accordance with the azimuth angles of 45 degrees, 135 degrees, 225, and 315 degrees counterclockwise, thereby collecting sounds in all directions.

  By arranging the microphones 2a to 2d in an oblique direction, the incident angle of sound approaches the incident angle to the human ear, so the accuracy of safety confirmation can be improved. A sound affected by reflection or the like around the head enters the ear, and the person perceives the direction of the sound image by sensing a change in the sound.

  FIG. 1C is a block diagram showing the configuration of the sound collecting / reproducing apparatus according to the first embodiment. The sound collecting / reproducing apparatus includes four microphones 2a to 2d, four binaural converters 5a to 5d, a binaural sound synthesizing unit 6, and a signal reproducing unit 7.

  The four binaural converters 5a to 5d are provided corresponding to the four microphones 2a to 2d, and the sound outside the vehicle (monaural sound) collected by the corresponding microphones is sound images corresponding to the direction of the microphone. Convert to directional binaural sound (stereo sound).

  By convolving and integrating the external sound collected by the microphone with the head impulse response, a binaural sound having a sound image direction corresponding to the directivity direction of the installed microphone can be obtained.

  Each binaural conversion unit 5a to 5d performs binaural conversion so that the sound is in the directivity direction of the corresponding microphone. Each binaural conversion unit 5a to 5d generates stereo sound of right front speaker sound (Rn), right rear speaker sound (RBn), left front speaker sound (Ln), and left rear speaker sound (LBn) by binaural conversion. n is 1-4.

  The binaural sound synthesizer 6 synthesizes the four binaural sounds converted by the four binaural converters 5a to 5d and the stereo sound of the sound source.

The binaural sound synthesizer 6 generates a pre-R signal, a pre-L signal, a post-R signal, and a post-L signal as follows.
R pre-signal = R1 + R2 ... Rn + original R pre-audio signal L pre-signal = L1 + L2 ... Ln + original L pre-audio signal R post-signal R = post R1 + R2 post-Rn + original post-R audio signal L post-signal = L1 + L2 ... The post-Ln + original post-L audio signal The signal reproducing unit 7 reproduces the binaural sound and the stereo sound synthesized by the binaural sound synthesizing unit 6, and includes a speaker or the like. FIG. 1 (d) shows the arrangement of the four speakers 3 a to 3 d constituting the signal reproduction unit 7. The four speakers 3 a to 3 d are arranged at 90 ° intervals at four corners of the vehicle 1 so as to sandwich the driver 4.

  The pre-R signal from the binaural sound synthesizer 6 is output to the speaker 3a disposed before R. The pre-L signal from the binaural sound synthesizer 6 is output to the speaker 3b arranged before L. The post-R signal of the binaural sound synthesizer 6 is output to the speaker 3c arranged after the R. The signal after L of the binaural sound synthesizer 6 is output to the speaker 3d arranged after L.

  Therefore, safety can be confirmed by reproducing the sound field outside the automobile with a car stereo using binaural conversion.

  Next, an experiment was conducted to subjectively evaluate the perceived accuracy of the sound image direction by the binaural sound of each azimuth angle created. As shown in FIG. 1B, a sound source 3 m away from the center was moved counterclockwise from 0 degrees in 30-degree increments to create 12-direction binaural sound data. White noise, motorcycle engine sounds, brake sounds, female screams and footsteps were used as sound sources.

  The front sound and the sound of each azimuth angle (12 azimuth random) are alternately reproduced, and the audible azimuth answers are tabulated. In consideration of actual sound image changes, each azimuth angle was continuously changed clockwise or counterclockwise for reproduction, and the answer of the azimuth angle that was heard last was obtained.

  FIG. 2 shows a perceptual orientation map of footstep sound sources as a representative experimental result. The target azimuth angle on the horizontal axis represents the actual azimuth angle of the sound source, and the perceived azimuth angle on the vertical axis represents the azimuth angle answered by the subject. In addition, the circle marker on the perceptual azimuth map is displayed larger when the number of people who answered the azimuth is larger, and smaller when the number is smaller. A circle marker on the diagonal line (solid line) of the perceptual direction map represents a correct answer, and if it is on the broken line, it means an error in the front-rear direction. The standard deviation of the difference with respect to the target azimuth corresponding to the 12 azimuths of the answer azimuth was an average of 45.3 degrees.

  From this result, it is considered that the omnidirectional angle of the footstep sound source could be generally perceived when viewed by the in-vehicle speaker.

  As described above, according to the sound collecting / reproducing apparatus of the first embodiment, three or more directional microphones 2a to 2d are placed on the ceiling or under the floor of the vehicle, instead of the left and right microphones having a pinna-like structure. The sound of each microphone is collected 360 degrees outside the vehicle, and the sound of each microphone is converted into a binaural sound in the sound image direction corresponding to the direction of the microphone by the binaural converters 5a5 to d, and the binaural sound synthesizer 6 Then, the binaural sound is synthesized and reproduced by the signal reproducing unit 7.

  Therefore, it is possible to drastically reduce the mistake of grasping the sound image according to the volume ratio according to the distance of surrounding vehicles and people outside the car, and by reproducing the sound field outside the car with a car stereo by binaural conversion, the driver adds to visual confirmation This makes it possible to grasp the reproduced sound image outside the vehicle. In addition, three or more microphones can drastically reduce mistakes in the front and back of the sound image, and the more the number of microphones, the better the sound image reproduction accuracy.

  In particular, there have recently been frequent accidents involving hitting a vehicle against an infant or an elderly person outside the vehicle when entering the garage, and the present invention can be expected to supplement the blind spot remaining in the conventional visual safety confirmation with hearing. In addition, safety can be improved even in cold environments, in-car sealed conditions during rainy weather, and in alleys and railroad crossings where visibility is hindered.

  Furthermore, since the sound collecting / reproducing apparatus can be reduced in size by the microphone, the appearance of the vehicle becomes inconspicuous, and an increase in the vehicle height can be suppressed. Conversely, a stylish design using the microphone itself as an accessory is also possible.

  In addition, by providing a windshield member such as a windshield sponge on each microphone, wind noise can be suppressed even when wind blows during traveling. If the vehicle is not traveling at a high speed, wind noise can be suppressed without providing a windshield member by the mute function of the microphone itself.

  FIG. 3 shows an example in which three microphones are provided on the front, left, and right in the sound collecting and reproducing apparatus according to the second embodiment. As shown in FIG. 3, the three microphones are composed of a microphone 2a arranged in the front front direction of the vehicle and microphones 2b and 2c arranged in the direction of 60 degrees left and right from the rear front. Each microphone 2a-2c is arrange | positioned mutually at intervals of 120 degree | times.

  According to the sound collecting / reproducing apparatus according to the second embodiment, the three microphones 2a to 2c are spaced 120 degrees apart, and the microphone 2a is directed forward and the microphones 2b and 2c are directed toward the left and right 60 degrees. Therefore, the accuracy of the rear sound image can be improved.

  FIG. 4 shows a configuration example of the sound collecting and reproducing apparatus according to the third embodiment. In the sound collecting and reproducing apparatus according to the third embodiment, four microphones 2a to 2d are arranged in the front-rear and left-right directions of the vehicle. The four microphones 2a to 2d are arranged at intervals of 90 degrees.

  According to the sound collecting and reproducing apparatus according to the third embodiment, the four microphones 2a to 2d are arranged at 90 degree intervals and in the front-rear and left-right directions of the vehicle. Can do.

  FIG. 5 shows a perceived azimuth angle with respect to a target azimuth angle when four microphones are provided on the left and right and front and rear in the sound collecting and reproducing apparatus according to the third embodiment. The measurement results when four microphones are provided on the left and right sides are not significantly different from the accuracy of the measurement results shown in FIG. 2 when four microphones are provided on the left and right sides, and both can be applied for safety confirmation. .

  FIG. 6 shows a configuration example of the sound collecting and reproducing apparatus according to the fourth embodiment. In the sound collecting / reproducing apparatus according to the fourth embodiment, four microphones 2a to 2d are arranged diagonally forward and backward from the left and right, away from the center on the ceiling and the floor. As shown in FIG. 6 (a), the microphones 2a to 2d having directivity can be used as the microphone. However, as shown in FIG. 6 (b), non-directionality having no directivity (omnidirectionality). ) Microphones 2a 'to 2d'.

  According to the sound collecting / reproducing apparatus according to the fourth embodiment, the four microphones 2a to 2d are arranged diagonally forward and backward from the left and right, and are arranged away from the center of the ceiling or the floor, so that the distance that can be collected can be increased. .

  In addition, as shown in FIG. 7, even when four omnidirectional (omnidirectional) microphones 2a 'to 2d' having no directivity are provided at the four corners of the vehicle, the range in which sound can be collected is expanded. can do.

  FIG. 8 shows an arrangement of dashboard speakers 3A1 and 3A2 including normal tweeters, normal door speakers 3B1 and 3B2, and normal rear speakers 2c1 and 2c2 in the sound collecting and reproducing apparatus according to the fifth embodiment. Dashboard speakers 3A1 and 3A2 are arranged on the front left and right, door speakers 3B1 and 3B2 are arranged on the center left and right, and rear speakers 2c1 and 2c2 are arranged on the rear left and right.

  Since the dashboard speakers 3A1 and 3A2 provided with directional tweeters are arranged on the front left and right, it is possible to accurately collect the sounds outside the vehicle on the front left and right.

  Further, as shown in FIG. 9, only the door speakers 3Ba and 3Bb are provided with directional tweeters at the center left and right, and the dashboard speakers 3Aa and 3Ab and the rear speakers 2c1 and 2c2 are used as normal speakers. The left and right vehicle exterior sounds can be collected with high accuracy.

  FIG. 10 is a block diagram of the main components of the sound collecting / reproducing apparatus according to the sixth embodiment. The binaural sound synthesizer 6a shown in FIG. 10 is based on the volume of the front microphones 2a and 2b among the outside sounds of the four microphones 5a to 5d corresponding to the four binaural sounds sent from the binaural converters 2a to 2d. Also, the volume of the rear microphones 2c and 2d is set large.

  The signal reproduction unit 7 sets the volume of the rear speaker to be larger than the sound image behind the front in accordance with the volume of the microphone of the binaural sound synthesis unit 6a.

  Thereby, since the sound image sensitivity of the back which cannot be directly seen during a driving | operation can be raised, safety | security can be improved.

  The binaural sound synthesizer 6a can also increase or decrease the volume of the sound source according to the magnitude of the sound outside the vehicle when synthesizing the stereo sound of the sound source and the sound outside the vehicle from the microphone.

  For example, the binaural sound synthesizer 6a can clarify the audio sound by increasing the volume of the sound source when the outside sound from the microphones 2a to 2d increases. Or, conversely, the audio sound can be reduced to suppress obscuration of the sound image outside the vehicle due to saturation or distortion of the speaker sound.

  The sound collecting / reproducing apparatus according to the seventh embodiment provides a noise cancellation system that reduces only noise generated inside the vehicle that is not necessary information sound outside the vehicle, thereby clarifying the sound outside the vehicle and the audio sound. Accordingly, the volume of the sound outside the vehicle and the audio sound is not set too high.

  FIG. 11 is a block diagram of the main components of the sound collecting / reproducing apparatus according to the seventh embodiment. This sound collecting / reproducing apparatus includes a vehicle body vibration sensor 8 and a noise canceller 9 in addition to the microphones 2a to 2d, the binaural converters 5a to 5d, the binaural sound synthesizer 6 and the signal reproducing unit 7 shown in FIG. Yes.

  The vehicle body vibration sensor 8 corresponds to the noise detection unit of the present invention and includes an acceleration sensor or the like. The vehicle body vibration sensor 8 is installed on the dashboard, the interior of the vehicle, on the door, floor, under the seat, trunk, etc., and detects noise generated in the vehicle due to engine and tire vibration. The vehicle body vibration sensor 8 is installed in a vehicle near the windshield, pillar, and door mirror, and detects noise caused by wind noise.

  Since the sound pressure generated from the vibration surface is proportional to the acceleration of the vibration surface, the sound pressure, that is, noise can be detected by the acceleration sensor. Recent acceleration sensors can be easily obtained at low cost as integrated circuits.

  The noise canceller 9 corresponds to the canceling signal generation unit of the present invention, and generates a noise canceling signal having an opposite phase to the noise signal based on the noise detected by the vehicle body vibration sensor 8.

  The binaural sound synthesizer 6b synthesizes the vehicle exterior sound, the stereo sound, and the noise cancellation signal generated by the noise canceller 9. The signal reproduction unit 7 reproduces the vehicle exterior sound, the stereo sound, and the noise cancellation signal synthesized by the binaural sound synthesis unit 6b. For this reason, the noise in the vehicle can be reduced by being canceled by the noise cancellation signal.

  In particular, it is possible to generate a reverse phase sound (sound by a noise canceling signal) with respect to noise in a wide range in the vehicle, and effectively reduce a low-frequency component having a long wavelength of about 100 Hz or less included in an engine or the like. The phase of the long wavelength is less dependent on the position in the vehicle, and a large reduction effect can be obtained over a wide range in the vehicle.

  As shown in FIG. 12, the sound collecting / reproducing apparatus according to the eighth embodiment is characterized by providing microphones 2a and 2b arranged on the left and right of the substantially center of the vehicle and a microphone 2c arranged on the rear side.

  Although not shown, binaural converters 5a to 5c are provided corresponding to the microphones 2a, 2b, and 2c, and the binaural sound synthesizer 6 is connected to the binaural converters 5a to 5c. The signal reproduction unit 7 is connected to the.

  In the sound collecting / reproducing apparatus according to the eighth embodiment, the microphones 2a and 2b disposed on the left and right sides of the substantially center of the vehicle and the microphone 2c disposed on the rear side are provided. However, the microphone 2c may be disposed only on the rear side. good.

  According to the sound collecting / reproducing apparatus according to the eighth embodiment, a single or a plurality of microphones are arranged in the rear other than the front or in the central left / right direction, and the external sound from the microphones 2a, 2b, 2c is output by the binaural converters 5a-5c. A binaural sound is generated by binaural conversion, and a binaural sound and a stereo sound of a sound source are reproduced by an arbitrary speaker of the signal reproduction unit 7. Therefore, it is possible to confirm a rear sound image that cannot be confirmed directly.

  As shown in FIG. 13A, the sound collecting and reproducing apparatus according to the ninth embodiment is provided with microphones 2a and 2b on the left and right sides, and with speakers 3a and 3b on the left and right sides.

  Although not shown, the synthesizing unit synthesizes the external sound collected by the two microphones 2a and 2b and the stereo sound of the sound source. The speakers 3a and 3b reproduce the external sound synthesized by the synthesis unit and the stereo sound of the sound source.

  Therefore, a rear sound image that cannot be confirmed by direct viewing can be confirmed without binaural conversion.

  Instead of the microphones 2a and 2b arranged on the left and right sides, directional microphones that are close to the center may be used, or omnidirectional microphones that are provided at the four corners of the vehicle.

  In addition, as shown in FIG. 13B, the sound collecting and reproducing apparatus according to Example 9 is provided with a microphone 2a at the rear and a speaker 3a at the rear. The synthesizing unit synthesizes the outside sound collected by the microphone 2a and the stereo sound of the sound source. The speaker 3a reproduces the external sound synthesized by the synthesizing unit and the stereo sound of the sound source.

  Therefore, a rear sound image that cannot be confirmed by direct viewing can be confirmed without binaural conversion.

  As shown in FIG. 14, the microphones having directivity constituting the above-described embodiments 1 to 9 are provided with a sound-absorbing material and a sound-absorbing plate 10 using the same, so that there is no directivity. Can be replaced by a directional (omnidirectional) microphone. Further, as shown in FIGS. 6 and 7, if the distance between the microphones is wide, the sound absorbing material and the sound absorbing plate 10 are not necessary.

DESCRIPTION OF SYMBOLS 1 Vehicle 2a-2d Microphone 2c1, 2c2 Rear speaker 3a-3b Speaker 3A1, 3A2 Dashboard speaker 3B1, 3B2 Door speaker 4 Driver 5a-5d Binaural conversion part 6, 6a, 6b Binaural sound synthesis part 7 Signal reproduction part 8 Car body Vibration sensor 9 Noise canceller 10 Sound absorbing material and sound absorbing plate

Claims (16)

Three or more microphones arranged outside the vehicle and collecting external sounds;
Three or more binaural conversion units that are provided corresponding to the three or more microphones, and convert outside sound collected by the corresponding microphones into binaural sounds in a sound image direction corresponding to the direction of the microphone;
A binaural sound synthesis unit that synthesizes three or more binaural sounds converted by the three or more binaural conversion units and a stereo sound of a sound source;
A signal reproduction unit for reproducing the binaural sound synthesized by the binaural sound synthesis unit and the stereo sound of the sound source;
A sound collecting and reproducing apparatus comprising:   The three or more microphones include first and second microphones arranged in a 45-degree direction from the front front, and third and fourth microphones arranged in a 45-degree direction from the rear front. The sound collecting / reproducing apparatus according to claim 1, comprising:   The three or more microphones include a first microphone disposed in front of the vehicle and a second microphone and a third microphone disposed in a 60-degree direction from the rear front. The sound collecting / reproducing apparatus according to claim 1.   2. The sound collecting / reproducing apparatus according to claim 1, wherein the three or more microphones include four microphones arranged in the front-rear and left-right directions of the vehicle.   5. The sound collecting / reproducing apparatus according to claim 1, wherein the three or more microphones are arranged apart from a center above the ceiling or under the floor of the vehicle.   The sound collecting reproduction according to any one of claims 1 to 4, wherein the three or more microphones include four microphones, and the four microphones are arranged at four corners of the vehicle. apparatus.   The sound collecting / reproducing apparatus according to claim 1, wherein the signal reproducing unit includes a speaker provided with a tweeter having high directivity.   8. The sound collecting / reproducing apparatus according to claim 7, wherein the speaker is a door speaker or a dashboard speaker provided with a highly directional tweeter. The binaural sound synthesizer sets a volume of a rear microphone larger than a volume of a front microphone of the three or more microphones,
9. The signal reproduction unit according to claim 1, wherein the volume of the rear speaker is set to be larger than the sound image behind the front in accordance with the volume of the microphone of the binaural sound synthesis unit. The sound collecting / reproducing apparatus according to the item.   9. The binaural sound synthesis unit, when synthesizing the stereo sound of the sound source and the outside sound, increases or decreases the volume of the sound source according to the magnitude of the outside sound. The sound collecting and reproducing device according to any one of the above. A noise detector for detecting noise generated in the vehicle;
A cancellation signal generation unit that generates a noise cancellation signal having an opposite phase to a noise signal based on the noise detected by the noise detection unit;
The sound collecting and reproducing apparatus according to claim 1, wherein the binaural sound synthesis unit synthesizes the stereo sound and a noise cancellation signal generated by the cancellation signal generation unit. One or more microphones arranged outside the vehicle and at the rear of the vehicle for collecting the sound outside the vehicle;
One or more binaural conversion units that are provided corresponding to the one or more microphones and convert external sound collected by the corresponding microphones into binaural sounds in a sound image direction corresponding to the direction of the microphone;
A binaural sound synthesis unit that synthesizes one or more binaural sounds converted by the one or more binaural conversion units and a stereo sound of a sound source;
A signal reproduction unit for reproducing the binaural sound synthesized by the binaural sound synthesis unit and the stereo sound of the sound source;
A sound collecting and reproducing apparatus comprising: One or more microphones arranged outside the vehicle and at the rear of the vehicle for collecting the sound outside the vehicle;
A synthesizing unit that synthesizes external sound collected by the one or more microphones and stereo sound of a sound source;
One or more speakers arranged at the rear of the vehicle corresponding to the one or more microphones and reproducing the external sound synthesized by the synthesis unit and the stereo sound of the sound source;
A sound collecting and reproducing apparatus comprising:   14. The sound collecting / reproducing apparatus according to claim 1, wherein the three or more microphones or the one or more microphones are directional microphones.   The three or more microphones or the one or more microphones are omnidirectional microphones, and a sound absorbing material or a sound absorbing plate is disposed between the omnidirectional microphones. The sound collecting / reproducing apparatus according to claim 7.   7. The sound collecting / reproducing apparatus according to claim 5, wherein the three or more microphones are omnidirectional microphones.

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