阅读说明：本技术 一种用于自动定向录音的录音笔、方法、主机和存储介质 (Recording pen, method, host and storage medium for automatic directional recording ) 是由 费邑兵 于 2021-08-25 设计创作，主要内容包括：本申请涉及一种用于自动定向录音的录音笔、方法、主机和存储介质,其包括笔体和录音头,录音头包括半球状的头部和圆柱状的连接部,连接部的顶面形成有第一参考面,头部的端面连接于连接部的顶面,头部的球心位于第一参考面上且连接部和头部的半径相同,连接部的底面能够在笔体的顶部转动且转动轴为连接部的轴线,头部的顶端设置有一个顶部拾音麦克风,头部的侧面设置有多个斜向拾音麦克风,录音头在第一参考面围绕转动轴的圆周上设置有多个周向拾音麦克风,头部的表面形成有拾音弧,拾音弧上落有的顶部拾音麦克风、斜向拾音麦克风和周向拾音麦克风。本申请具有使得录音笔进行定向拾音以获得高质量的录音的效果。(The application relates to a recording pen for automatically directionally recording, a method, a host and a storage medium, which comprise a pen body and a recording head, wherein the recording head comprises a hemispherical head and a cylindrical connecting part, a first reference surface is formed on the top surface of the connecting part, the end surface of the head is connected to the top surface of the connecting part, the center of sphere of the head is positioned on the first reference surface, the radius of the connecting part and the radius of the head are the same, the bottom surface of the connecting part can rotate at the top of the pen body, and the rotating shaft is the axis of the connecting part, a top pickup microphone is arranged at the top end of the head, a plurality of oblique pickup microphones are arranged on the side surface of the head, a plurality of circumferential pickup microphones are arranged on the circumference of the first reference surface around the rotating shaft, a pickup arc is formed on the surface of the head, and the top microphones, the oblique pickup microphones and the circumferential pickup microphones are arranged on the pickup arc. The sound recording pen has the effect that the sound recording pen carries out directional sound pickup to obtain high-quality sound recording.)

1. The utility model provides a recording pen for automatic directional recording, characterized in that, including being used for the handwriting (1) that grips and setting up in recording head (2) on handwriting (1) top, recording head (2) are including hemispherical head (21) and cylindric connecting portion (22), the top surface of connecting portion (22) is formed with first reference surface (8), the terminal surface of head (21) connect in the top surface of connecting portion (22), the centre of sphere (7) of head (21) are located first reference surface (8) just connecting portion (22) with the radius of head (21) is the same, the bottom surface of connecting portion (22) can rotate and axis of rotation (6) are in the top of handwriting (1) the axis of connecting portion (22), the top of head (21) is provided with a top pickup microphone (33), the side of head (21) is provided with a plurality of slant microphones (32) on the hoop around axis of rotation (6) and picks up a sound ) The recording head (2) is provided with a plurality of circumferential sound pickup microphones (31) on the circumference of a first reference surface (8) around the rotating shaft (6), a sound pickup arc (5) is formed on the surface of the head (21), and the top sound pickup microphone (33), the oblique sound pickup microphone (32) and the circumferential sound pickup microphones (31) are arranged on the sound pickup arc (5).

2. A recording pen according to claim 1, characterized in that the central angle of the slant microphone (32) to the top microphone (33) with respect to the center of sphere (7) is a first central angle (41), the central angle of the slant microphone (32) to the first reference surface (8) with respect to the center of sphere (7) is a second central angle (42), and the absolute value of the difference between the first central angle (41) and the second central angle (42) is larger than a first threshold value.

3. The recording pen according to claim 1, characterized in that a servo motor or a stepping motor is arranged in the pen body (1) for driving the recording head (2) to rotate, and an internal pickup microphone (34) is arranged in the pen body (1).

4. The recording pen according to claim 1, characterized in that the surface of the head (21) is formed with a plurality of pickup semi-arcs passing through the top pickup microphone (33), the number of the oblique pickup microphones (32) and the circumferential pickup microphones (31) are equal and all fall on the pickup semi-arcs, so that the microphones on each pickup semi-arc are arranged as the circumferential pickup microphone (31), the oblique pickup microphone (32), the top pickup microphone (33), the oblique pickup microphone (32) and the circumferential pickup microphone (31).

5. The sound recording pen as claimed in claim 4, characterized in that the pickup semi-arcs are evenly distributed in the circumferential direction around the rotational axis (6), the oblique pickup microphones (32) being located on the same circumference around the rotational axis (6).

6. An automatic directional recording method applied to the recording pen according to any one of claims 1 to 5, comprising the steps of:

positioning a target sound source based on microphones on the sound collecting arcs (5) to obtain the azimuth information of the target sound source, and taking the sound collecting arc (5) closest to the target sound source as a main sound collecting arc (5);

controlling the recording head (2) to rotate so that the main sound-collecting arc (5) rotates to the position closest to the target sound source;

based on the positioning result, taking two closest to the target sound source on the main sound-collecting arc (5) as main sound-collecting microphones, and acquiring sound-collecting wave beams emitted by the target sound source based on the main sound-collecting microphones;

ambient sound is acquired based on microphones other than the main sound pickup microphone and the oblique main microphone, and noise reduction is performed on the sound pickup beam based on the sound pickup beam and the ambient sound.

7. The automatic directional recording method according to claim 6, wherein said step of locating a target sound source based on microphones on respective sound arcs (5) to obtain target sound source bearing information, and regarding the sound arc (5) closest to the target sound source as the primary sound arc (5), comprises the steps of:

acquiring sound recorded by a microphone on a sound collecting arc (5) and extracting target sound source azimuth information, wherein the target sound source azimuth information comprises receiving time difference information, frequency information and amplitude information;

and fitting and determining the position of the target sound source based on the position information acquired by each sound-collecting arc (5), wherein the position of the target sound source acquired by each sound-collecting arc (5) is positioned on the plane where the sound-collecting arc (5) is positioned.

8. The method of claim 7, wherein the step of de-noising the pickup beam based on the pickup beam and ambient sounds comprises the steps of:

suppressing, based on the pickup beam, sound recording by a microphone other than the main pickup microphone;

and denoising the pickup wave beam based on the environment sound so as to obtain the sound emitted by the target sound source.

9. An automated directional recording system, comprising:

the positioning module is used for positioning a target sound source based on the microphones on the sound-collecting arcs (5) to obtain the azimuth information of the target sound source, and the sound-collecting arc (5) closest to the target sound source is taken as a main sound-collecting arc (5);

the calibration module is used for controlling the recording head (2) to rotate so that the main sound-picking arc (5) rotates to the position closest to the target sound source;

the recording module is used for taking two closest to the target sound source on the main sound-picking arc (5) as main sound-picking microphones based on the positioning result and acquiring sound-picking wave beams emitted by the target sound source based on the main sound-picking microphones;

and the noise reduction module acquires ambient sound based on the microphones except the main pickup microphone and the inclined main microphone, and reduces noise of the pickup beam based on the pickup beam and the ambient sound.

10. A readable storage medium, characterized in that a computer program is stored which can be loaded by a processor and which executes the method for automatically directing recording as claimed in any one of claims 6 to 8.

Technical Field

The present application relates to the field of recording pens, and in particular, to a recording pen, a method, a host, and a storage medium for automatically directing recording.

Background

In daily life, a recording pen is often used, and generally, the recording pen includes a microphone, a control circuit connected to the microphone, and a memory connected to the control circuit, and the microphone records and inputs sound to the control circuit for processing, and finally stores the sound in the memory. The recording pen is used in a conference, a study or a conversation recording process, and in real life, for example, the position of a speaker in the conference is not fixed, and a user and the speaker move in position in an interview process, which makes it difficult for a microphone to be aligned with the speaker, so that the recording effect is poor, or a large amount of noise is mixed in the microphone, and great difficulty is encountered in audio processing at a later stage.

Disclosure of Invention

In order to be able to obtain high quality recordings, the application provides a recording pen, a method, a host and a storage medium for automatic directional recording.

In a first aspect, the application provides a recording pen for automatically directionally recording, which adopts the following technical scheme: a recording pen for automatically and directionally recording comprises a pen body for holding and a recording head arranged at the top end of the pen body, wherein the recording head comprises a hemispherical head and a cylindrical connecting part, a first reference surface is formed on the top surface of the connecting part, the end surface of the head is connected to the top surface of the connecting part, the center of sphere of the head is positioned on the first reference surface, the radius of the connecting part is the same as that of the head, the bottom surface of the connecting part can rotate at the top of the pen body, the rotating shaft is the axis of the connecting part, a top pickup microphone is arranged at the top end of the head, a plurality of oblique pickup microphones are arranged on the side surface of the head in the circumferential direction around the rotating shaft, a plurality of circumferential pickup microphones are arranged on the circumference of the first reference surface around the rotating shaft, and a pickup arc is formed on the surface of the head, the top pickup microphone, the oblique pickup microphone and the circumferential pickup microphone are arranged on the pickup arc.

By adopting the technical scheme, each group of oblique sound pickup microphones and each group of circumferential sound pickup microphones form sound pickup arcs with the top sound pickup microphone, the microphones on the sound pickup arcs are matched with each other to position a speaker, and then the final positioning is obtained based on a statistical formula. The recording head can be rotated so that a pickup arc is directed at the speaker. In the related art, a microphone array for a conference room is generally disposed in a circumferential direction and at the same level as a speaker to facilitate recording, and thus the sound pickup problem of the microphone array corresponds to a two-dimensional problem. However, since the recording pen has different habits among users and the recording pen is not fixed in height and direction, the problem of collecting sound by the recording pen corresponds to a three-dimensional problem. In the scheme, the recording pen can adjust the orientation of the pickup arc by rotating the recording head to align the pickup arc with the target, and then determines two microphones closest to the target on the pickup arc to be used as main pickup microphones to acquire pickup of the target. Similarly, other sound arcs may be directed at other speakers speaking simultaneously to capture the pickup of other targets. Finally, other microphones than the main pickup microphone collect ambient sounds in various directions for noise reduction of the pickup beam obtained by the main pickup, thereby obtaining a high-quality recording.

In addition, suppose a scheme that utilizes auxiliary microphone to confirm the sound source direction, and then carries out horizontal and longitudinal rotation with main pickup microphone in order to aim at the sound source, this is equivalent to the mechanical structure of a biax in fact, because the volume of recording pen is little, the biax can be repeated the motion, can produce great internal noise in fact and cause the influence to the pickup, realize with high costs, power consumptive fast and difficult maintenance. In the scheme, the problem of misalignment of pickup can be solved by matching a plurality of microphones and only using a single shaft, and the defects generated by a double-shaft scheme are avoided.

Optionally, the central angle of the slant sound pickup microphone to the top sound pickup microphone relative to the center of sphere is a first central angle, the central angle of the slant sound pickup microphone to the first reference plane relative to the center of sphere is a second central angle, and an absolute value of a difference between the first central angle and the second central angle is greater than a first threshold.

Through adopting above-mentioned technical scheme, the absolute value of the difference of first central angle and second central angle is greater than first threshold value for not equidistance between circumference pickup microphone, slant pickup microphone and the top pickup microphone on the same pickup arc. Based on the characteristic that the distance from the sound source to each microphone is different, the sound production direction can be determined and the sound source can be located by using a time domain and trigonometric function calculation formula of sound source propagation. And this kind of unequal distance sets up the unbalance nature of amplifying microphone received information effectively to make the slant pickup microphone on the pickup arc and the adjacent sound signal on the sound source direction of microphone receipt nearer apart from the sound source for main pickup and carry out directional pickup, other microphones restrain the environmental sound that is different from main pickup frequency domain when carrying out the recording, thereby promote pickup quality and guarantee the recognition effect.

Optionally, a servo motor or a stepping motor for driving the recording head to rotate is arranged in the pen body, and an internal pickup microphone is arranged in the pen body.

By adopting the technical scheme, the servo motor and the stepping motor can accurately control the rotation angle of the recording head, so that the pickup arc is accurately aligned to the target sound source. Simultaneously, the noise of the motor is recorded by the internal pickup microphone, so that the corresponding noise can be filtered out from the main pickup in the later period.

Optionally, the surface of head is formed with a plurality of adapterization semicircle through top adapterization microphone, slant adapterization microphone equals and all falls on the adapterization semicircle with the quantity of circumference adapterization microphone to make the microphone on every adapterization semicircle arrange for circumference adapterization microphone, slant adapterization microphone, top adapterization microphone, slant adapterization microphone and circumference adapterization microphone.

By adopting the technical scheme, the two sound collecting arcs are connected into a sound collecting semicircular arc, and compared with a quarter circular arc, the five microphones are matched with each other to more accurately collect sound so as to determine the direction of a target sound source.

Optionally, the pickup semicircle is around the circumference of axis of rotation evenly distributed, the slant pickup microphone is located around the same circumference of axis of rotation.

By adopting the technical scheme, the central angles from each oblique sound pickup microphone to the first reference surface relative to the sphere center are equal, so that the parameters in the calculation of the target azimuth are reduced, and the calculation efficiency is improved.

In a second aspect, the application provides an automatic directional recording method, which adopts the following technical scheme:

an automatic directional recording method is applied to the recording pen, and comprises the following steps:

positioning a target sound source based on the microphones on the pickup arcs to obtain the azimuth information of the target sound source, and taking the pickup arc closest to the target sound source as a main pickup arc;

controlling the recording head to rotate so that the main sound-picking arc rotates to the position closest to the target sound source;

taking two closest to the target sound source on the main sound-collecting arc as main sound-collecting microphones based on the positioning result, and acquiring sound-collecting wave beams emitted by the target sound source based on the main sound-collecting microphones;

ambient sound is acquired based on microphones other than the main sound pickup microphone and the oblique main microphone, and noise reduction is performed on the sound pickup beam based on the sound pickup beam and the ambient sound.

Through adopting above-mentioned technical scheme, the microphone is based on the pickup arc and is divided into groups, and each group's slant pickup microphone and circumference pickup microphone all form the pickup arc with top pickup microphone. And controlling a microphone on each pickup arc to acquire the sound emitted by the target sound source so as to position the target sound source, and then obtaining the final positioning based on a statistical formula, so that one pickup arc is aligned to the speaker and serves as a main pickup arc. The recording head rotates to make the main sound-collecting arc aim at the target sound source for obtaining the sound-collecting wave beam emitted by the target sound source. Based on the localization of the target sound source, the two microphones on the sound-pickup arc closest to the target may be determined to act as the master sound-pickup microphone to acquire the picked-up sound of the target. And finally, carrying out environment pickup by using the rest other microphones, and reducing noise of pickup beams based on the pickup beams and environment sounds so as to further improve the recording quality.

Because the absolute value of the difference of first central angle and second central angle is greater than first threshold value for not equidistance between top pickup microphone, slant pickup microphone and the hoop pickup microphone on same pickup arc. By the different characteristics of the distance from the sound source to each microphone, the time domain and trigonometric function calculation formula of sound source propagation can be utilized to determine the sound production direction and locate the sound source. And this kind of unequally spaced setting enlargies the imbalance of microphone received information effectively to make the main pickup microphone on the pickup arc for main pickup and carry out directional pickup, other microphones restrain the environmental sound that is different from main pickup frequency domain when carrying out the recording, thereby promote pickup quality and guarantee the recognition effect.

Optionally, the step of positioning the target sound source based on the microphones on the respective pickup arcs to obtain the azimuth information of the target sound source, and taking the pickup arc closest to the target sound source as the main pickup arc includes the following steps:

acquiring sound recorded by a microphone on a sound collecting arc and extracting target sound source azimuth information, wherein the target sound source azimuth information comprises receiving time difference information, frequency information and amplitude information;

and fitting and determining the position of the target sound source based on the position information acquired by each sound-collecting arc, wherein the position of the target sound source acquired by each sound-collecting arc is positioned on the plane where the sound-collecting arc is positioned.

By adopting the technical scheme, the plurality of sound collecting arcs can obtain a plurality of groups of target sound source azimuth information, the target sound source azimuth information is the direction of the target sound source relative to the recording pen, and the range of the target sound source obtained by each group of sound collecting arcs is located on the plane where each group of sound collecting arcs is located. A weighted calculation is performed by the plurality of target sound source azimuth information to obtain the azimuth of the sound source.

The target sound source direction information includes a plurality of sounds of different frequencies and different amplitudes, and it is confirmed from the plurality of sounds that the frequency satisfies the frequency range, and the sound of which the amplitude satisfies the amplitude range is the sound of the target sound source, that is, the sound of the speaker, and the remaining sounds are the reference sounds. Further, the frequency range and the amplitude range may be the frequency range and the amplitude range of the human voice collected by the microphone when the user is in the collecting range of the recording pen and normally speaks during the interview or the conversation of multiple persons.

Optionally, the step of reducing noise of the pickup beam based on the pickup beam and the ambient sound includes the steps of: suppressing, based on the pickup beam, sound recording by a microphone other than the main pickup microphone;

and denoising the pickup wave beam based on the environment sound so as to obtain the sound emitted by the target sound source.

By adopting the technical scheme, the microphone suppresses the noise with different frequency or wavelength from the voice frequency or wavelength of the speaker when receiving all the voice signals, so that the pickup quality is improved and the recognition effect is ensured.

In a third aspect, the present application provides an automatic directional recording system, which adopts the following technical solution:

an automated directional recording system comprising:

the positioning module is used for positioning the target sound source based on the microphones on the pickup arcs to obtain the azimuth information of the target sound source, and the pickup arc closest to the target sound source is taken as a main pickup arc;

the calibration module is used for controlling the recording head to rotate so that the main sound-picking arc rotates to the position closest to the target sound source;

the recording module is used for taking two closest target sound sources on the main sound-picking arcs as main sound-picking microphones based on the positioning result and acquiring sound-picking wave beams emitted by the target sound sources based on the main sound-picking microphones;

and the noise reduction module acquires ambient sound based on the microphones except the main pickup microphone and the inclined main microphone, and reduces noise of the pickup beam based on the pickup beam and the ambient sound.

By adopting the technical scheme, the positioning module acquires the sound emitted by the target sound source based on the microphone on each pickup arc so as to position the target sound source, and then obtains the final positioning based on the statistical formula, and makes one pickup arc aim at the speaker and serve as the main pickup arc. The calibration module controls the recording head to rotate so that the main sound-collecting arc is aligned with the target sound source and is used for acquiring sound-collecting beams emitted by the target sound source. The recording module may determine the two microphones on the pickup arc that are closest to the target based on the location of the target sound source, making them the master pickup microphone to capture the pickup of the target. The noise reduction module utilizes the rest other microphones to carry out environment pickup, and noise reduction is carried out on pickup beams based on the pickup beams and environment sounds, so that the recording quality is further improved.

In a fourth aspect, the present application provides a host, which adopts the following technical solution:

a host comprising a memory and a processor, the memory having stored thereon a computer program that can be loaded by the processor and executed to perform the method as described above.

In a fifth aspect, the application provides a readable storage medium, which adopts the following technical solutions:

a readable storage medium storing a computer program capable of being loaded by a processor and executing the method as above.

Drawings

Fig. 1 is a schematic diagram illustrating an overall recording pen for automatically directing recording in an embodiment of the present application.

Fig. 2 is a schematic diagram illustrating a section of a recording pen along a rotation axis for automatic directional recording according to an embodiment of the present application.

Fig. 3 is a block flow diagram illustrating an automatic directional recording method according to an embodiment of the present application.

Fig. 4 is a block flow diagram illustrating the S1 sub-step in an embodiment of the present application.

Fig. 5 is a block flow diagram illustrating the S5 sub-step in an embodiment of the present application.

Description of reference numerals:

1. a pen body; 2. a recording head; 21. a head portion; 22. a connecting portion; 31. a circumferential pickup microphone; 32. an oblique sound pickup microphone; 33. a top pickup microphone; 34. an internal pickup microphone; 41. a first central angle; 42. a second central angle; 5. a sound-collecting arc; 6. a rotating shaft; 7. a spherical center; 8. a first reference surface; 9. an electric motor.

Detailed Description

The present application will be described in further detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the inventive concepts. Some of the figures in the present disclosure show structures and devices in block diagram form as part of this specification to avoid obscuring the disclosed principles. In the interest of clarity, not all features of an actual implementation are described in this specification. Moreover, the language used in the present disclosure has been principally selected for readability and instructional purposes, and may not have been selected to delineate or circumscribe the inventive subject matter, resort to the claims being necessary to determine such inventive subject matter. Reference in the present disclosure to "one implementation" or "an implementation" means that a particular feature, structure, or characteristic described in connection with the implementation is included in at least one implementation, and references to "one implementation" or "an implementation" are not to be understood as necessarily all referring to the same implementation.

The embodiment of the application discloses a recording pen for automatically and directionally recording. Referring to fig. 1 and 2, the recording pen includes a pen body 1 and a recording head 2. The pen body 1 is used for being held by a user, a power supply, a control system and a memory are usually arranged in the pen body, the power supply is used for supplying power to the recording head 2 and the control system, the control system carries out difference control on a microphone on the recording head 2 based on an automatic directional recording method so as to obtain clearer recording, and the memory is used for storing the recording processed by the control system. The recording head 2 is arranged at the top end of the pen body 1 and used for recording the sound of a target sound source, wherein a plurality of microphones are arranged on the recording head 2, when the recording head is used, all the microphones locate the target sound source and drive the recording head 2, so that part of the microphones aim at the target sound source and obtain the sound production of the target sound source, and other parts of the microphones acquire environmental sound to reduce the noise of auxiliary recording, thereby improving the recording quality.

The pen body 1 may be cylindrical, square or other shape, but it is convenient to hold and sufficiently contain the power supply, control system and memory, as an example, in one embodiment provided by the present application, the pen body 1 is cylindrical. It should be noted here that the number of the recording heads 2 is not limited to one, and in order to adapt to the cylindrical pen body 1 structure, in one specific implementation provided by the present application, the number of the recording heads 2 is one and is disposed on the top of the pen body 1.

Specifically, the recording head 2 includes a hemispherical head 21 and a cylindrical connecting portion 22, a first reference surface 8 is formed on a top surface of the connecting portion 22, an end surface of the head 21 is connected to the top surface of the connecting portion 22, a center 7 of the head 21 is located on the first reference surface 8, and the connecting portion 22 and the head 21 have the same radius. The bottom surface of the connecting portion 22 is rotatably connected to the top of the pen body 1, and in different implementations, the diameter of the connecting portion 22 may be larger than, equal to, or smaller than the diameter of the pen body 1, for example, in one implementation provided by the present application, the diameter of the connecting portion 22 is equal to the diameter of the pen body 1.

The recording head 2 can rotate on the top of the pen body 1, and the rotating shaft 6 is the axis of the connecting part 22, in different implementations, a servo motor 9 or a stepping motor 9 or other motors 9 for controlling the rotating angle with high precision are arranged in the pen body 1, and the rotating shaft 6 of the motor 9 is fixed with the connecting part 22 and is coaxial with the connecting part 22. For example, the positioning accuracy of the servo motor 9 depends on the resolution of the encoder, and in the case of a 2500-line incremental encoder, for example, the driver multiplies 4 times the encoder signal input to the motor 9, so as to control the positioning accuracy of the servo motor 9 to ± 1/(2500 × 4), and the angle to ± 360/(2500 × 4) ± 0.036 degrees, without accumulation of errors, and the microphone on the recording head 2 can be aligned to the target sound source with high accuracy by driving the high-accuracy motor 9.

Specifically, the top end of the rotating part is provided with a top pickup microphone 33, that is, the top pickup microphone 33 is located at the vertex of the hemisphere far from the pen body 1. The side of the rotating portion is provided with a plurality of oblique sound pickup microphones 32, the number of which can be adjusted, and the plurality of oblique sound pickup microphones 32 may be provided on the same circumference around the rotating shaft 6, or may be provided on different circumferences, that is, the distances between the oblique sound pickup microphones 32 and the top sound pickup microphones 33 may be the same, or may be different. In addition, the pitch of the oblique sound pickup microphones 32 in the circumferential direction around the rotation axis 6 may be the same or different, and the difference in position determines the difference in parameters of the control system algorithm, but these parameters may be adaptively adjusted based on the recording method given in the present application. By way of example, in one implementation provided herein, the oblique sound pickup microphones 32 are four in number and evenly distributed on the same circumference around the rotation axis 6.

The joint of the head 21 and the connecting part 22 is provided with a plurality of circumferential sound-pickup microphones 31, and the circumferential sound-pickup microphones 31 are all positioned on the first reference surface 8. Specifically, the circumferential sound pickup microphones 31 are provided corresponding to the oblique sound pickup microphones 32, in other words, the number of the circumferential sound pickup microphones 31 is the same as the number of the oblique sound pickup microphones 32, and the circumferential sound pickup microphones and the oblique sound pickup microphones 32 are in one-to-one correspondence in position. Thus, the surface of the head 21 is formed with the sound-collecting arc 5, and the top sound-collecting microphone 33, the oblique sound-collecting microphone 32, and the circumferential sound-collecting microphone 31 are dropped on the sound-collecting arc 5. Based on the specific implementation given by way of example above, the circumferential sound pickup microphones 31 are also four in number and evenly distributed on the same circumference around the rotational axis 6, in other words, the sound pickup arcs 5 are four in number and evenly distributed around the rotational axis 6. Two relative sound collecting arcs 5 can connect and form the pickup semicircle, and the microphone on every pickup semicircle is arranged for circumference pickup microphone 31, slant pickup microphone 32, top pickup microphone 33, slant pickup microphone 32 and circumference pickup microphone 31.

In order to improve the sound pickup effect, based on the specific implementation given by the above example, the central angle of the oblique sound pickup microphone 32 to the top sound pickup microphone 33 with respect to the center of sphere 7 is the first central angle 41, the central angle of the oblique sound pickup microphone 32 to the first reference surface 8 with respect to the center of sphere 7 is the second central angle 42, and the absolute value of the difference between the first central angle 41 and the second central angle 42 is equal to or greater than the first threshold value. For example, the angle between the oblique microphone 32 and the first reference surface 8 with respect to the center 7 is 55 degrees, the angle between the top microphone 33 and the oblique microphone 32 with respect to the center 7 is 35 degrees, and the first threshold is 10 degrees. For another example, the angle between the oblique sound pickup microphone 32 and the first reference surface 8 with respect to the center 7 is 40 degrees, the angle between the top sound pickup microphone 33 and the oblique sound pickup microphone 32 with respect to the center 7 is 50 degrees, and the first threshold value is 8 degrees.

Each of the pickup arcs 5 positions the speaker and drives the rotation of the rotating portion so that one pickup arc 5 is aligned with the speaker and serves as a main pickup arc. The absolute value of the difference between the first central angle 41 and the second central angle 42 is larger than the first threshold value, so that the fixed pickup microphone, the top pickup microphone 33, and the fixed pickup microphone on the same arc 5 are not equidistant from each other. By the different characteristics of the distance from the sound source to each microphone, the time domain and trigonometric function calculation formula of sound source propagation can be utilized to determine the sound production direction and locate the sound source. The unequal distance setting effectively amplifies the imbalance of the information received by the microphones, so that sound signals of the two microphones which are close to the sound source on the main sound-collecting arc in the received sound source direction are taken as main sound-collecting and directionally sound-collecting, and other microphones restrain environmental sounds which are different from a main sound-collecting frequency domain when recording, so that the sound-collecting quality is improved, and the recognition effect is guaranteed.

Further, since the motor 9 generates noise when operating, an internal sound pickup microphone 34 for picking up the noise generated by the operation of the motor 9 is provided inside the pen body 1. The internal pick-up microphone 34 records the noise of the operation of the motor 9 so that the corresponding noise is filtered from the main pick-up at a later stage.

Referring to fig. 3, the embodiment of the present application further discloses an automatic directional recording method, which is applied to the recording pen, and includes the following steps, but the order of the reference numbers of the following steps does not limit the method.

S1, positioning a target sound source based on microphones on all sound collecting arcs 5 to obtain azimuth information of the target sound source, and taking the sound collecting arc 5 closest to the target sound source as a main sound collecting arc.

The microphones are grouped on the basis of the sound-collecting arcs 5, each group of the oblique sound-collecting microphone 32 and the circumferential sound-collecting microphone 31 forming a sound-collecting arc 5 with the top sound-collecting microphone 33. And controlling a microphone on each sound-collecting arc 5 to acquire the sound emitted by the target sound source so as to position the target sound source, and then obtaining the final positioning based on a statistical formula, and enabling one sound-collecting arc 5 to be aligned with the speaker and serve as a main sound-collecting arc. The main sound-collecting arcs can be determined by the volume of the target sound source received by the microphones on the different sound-collecting arcs 5, the sequence of the target sound source received by the microphones on the different sound-collecting arcs 5, or other methods, but any method capable of determining the sound-collecting arc 5 closest to the target sound source can be used.

Referring to fig. 4, as an example, in one specific implementation presented herein, S1 includes the following steps:

s11, obtaining the sound recorded by the microphone on the sound collecting arc 5 and extracting target sound source azimuth information, wherein the target sound source azimuth information comprises receiving time difference information, frequency information and amplitude information.

S12, fitting and determining the position of the target sound source based on the position information acquired by the sound-collecting arcs 5, wherein the position of the target sound source acquired by each sound-collecting arc 5 is located on the plane where the sound-collecting arc 5 is located.

The plurality of sound-collecting arcs 5 can obtain a plurality of groups of target sound source azimuth information, the target sound source azimuth information is the direction of the target sound source relative to the recording pen, and the range of the target sound source obtained by each group of sound-collecting arcs 5 is located on the plane where each group of sound-collecting arcs 5 is located. A weighted calculation is performed by the plurality of target sound source azimuth information to obtain the azimuth of the sound source.

The target sound source direction information includes a plurality of sounds of different frequencies and different amplitudes, and it is confirmed from the plurality of sounds that the frequency satisfies the frequency range, and the sound of which the amplitude satisfies the amplitude range is the sound of the target sound source, that is, the sound of the speaker, and the remaining sounds are the reference sounds. Further, the frequency range and the amplitude range may be the frequency range and the amplitude range of the human voice collected by the microphone when the user is in the collecting range of the recording pen and normally speaks during the interview or the conversation of multiple persons.

For example, obtaining the target sound source azimuth information may be obtained by using the following algorithm:

firstly, setting the direction of a target sound source as theta, the time domain frequency of sound as omega, the propagation speed of sound in air as v, and the wave beam emitted by the target sound source as k, then

Where λ is the wavelength corresponding to frequency ω. Since the time at which the sound of the target sound source reaches each fixed pickup microphone is different, the sound received by the fixed pickup microphone array can be expressed as:

wherein, tau_nFor the time delay of the sound received by the nth microphone relative to the fixed main microphone, T represents transposition, and N is the number of fixed pickup microphones. According to the formula and the sound of the target sound source acquired by each microphone, the direction theta of the target sound source on the first reference surface relative to the recording pen can be obtained.

Alternatively, the average direction may be calculated by a method similar to the method for calculating the center of the set

And S2, controlling the recording head 2 to rotate so that the main sound-collecting arc rotates to the position closest to the target sound source.

And S3, taking two closest target sound sources on the main sound collecting arc as main sound collecting microphones based on the positioning result, and acquiring sound collecting wave beams emitted by the target sound sources based on the main sound collecting microphones.

The recording head 2 rotates so that the main sound-pickup arc is directed to the target sound source for acquiring the sound-pickup beam emitted from the target sound source. The two microphones closest to the target on the sound-collecting arc 5 can be determined based on the localization of the target sound source as the primary sound-collecting microphones to obtain the sound-collection of the target. Since the first central angle 41 and the second central angle 42 are different, in combination with the above formula, the sound can be picked up more accurately. Due to the different central angle settings, the imbalance of information received by the microphones is effectively amplified, so that sound signals received by the oblique sound pickup microphone 32 on the sound pickup arc 5 and the adjacent microphone closer to the sound source are mainly picked up and directionally picked up.

And S4, acquiring ambient sound based on the microphones except the main pickup microphone and the inclined main microphone, and reducing noise of the pickup beam based on the pickup beam and the ambient sound.

The main pickup microphone on the pickup arc 5 mainly picks up sound signals in the received sound source direction and carries out directional pickup, and other microphones suppress environmental sounds different from the main pickup frequency domain when recording, so that pickup quality is improved and the recognition effect is ensured.

Referring to fig. 5, as an example, in one specific implementation presented herein, S4 includes the following steps:

s41. suppressing the microphones other than the main sound pickup microphone from sound recording based on the sound pickup beam.

And S42, denoising the pickup wave beam based on the environment sound to obtain the sound emitted by the target sound source.

The ambient sound here also includes, in a broad sense, noise generated inside the recording pen, such as friction sound generated when the recording head is rotated, rotation sound and current sound generated when the motor 9 is operated, and the internal sound pickup microphone 34 picks up such ambient sound for noise reduction of the sound pickup beam. In summary, the microphone suppresses noise different from the speaker's voice frequency or wavelength when receiving all voice signals, thereby improving the pickup quality and ensuring the recognition effect.

The embodiment of the present application further discloses an automatic directional recording system, including:

the positioning module is used for positioning a target sound source based on the microphones on the sound collecting arcs 5 to obtain the azimuth information of the target sound source, and the sound collecting arc 5 closest to the target sound source is used as a main sound collecting arc;

the calibration module is used for controlling the recording head 2 to rotate so that the main sound-picking arc rotates to the position closest to the target sound source;

the recording module is used for taking two closest target sound sources on the main sound-picking arcs as main sound-picking microphones based on the positioning result and acquiring sound-picking wave beams emitted by the target sound sources based on the main sound-picking microphones;

and the noise reduction module acquires ambient sound based on the microphones except the main pickup microphone and the inclined main microphone, and reduces noise of the pickup beam based on the pickup beam and the ambient sound.

The embodiment of the application also discloses a host which comprises a memory and a processor, wherein the memory is stored with a computer program which can be loaded by the processor and can execute the automatic directional recording method. The execution main body of the method of this embodiment may be a control device, the control device is disposed on a host, the current device may be an electronic device such as a mobile phone, a tablet computer, and a notebook computer with a WIFI function, and the execution main body of the method of this embodiment may also be a Central Processing Unit (CPU) of the electronic device directly.

The embodiment of the application also discloses a readable storage medium which stores a computer program capable of being loaded by a processor and executing the automatic directional recording method. Through the above description of the embodiments, those skilled in the art will clearly understand that the method of the above embodiments can be implemented by software plus a necessary general hardware platform, and certainly can also be implemented by hardware, but in many cases, the former is a better implementation manner. Based on such understanding, the technical solutions of the present application may be embodied in the form of a software product, which is stored in a storage medium (e.g., ROM/RAM, magnetic disk, optical disk) and includes instructions for enabling a device (e.g., a mobile phone, a computer, a server, a controlled terminal, or a network device) to execute the method of each embodiment of the present application.

The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.