ES2588394B2 - Virtual acoustic dummy for biaural sound capture - Google Patents
Virtual acoustic dummy for biaural sound capture Download PDFInfo
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- ES2588394B2 ES2588394B2 ES201530592A ES201530592A ES2588394B2 ES 2588394 B2 ES2588394 B2 ES 2588394B2 ES 201530592 A ES201530592 A ES 201530592A ES 201530592 A ES201530592 A ES 201530592A ES 2588394 B2 ES2588394 B2 ES 2588394B2
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R5/00—Stereophonic arrangements
- H04R5/027—Spatial or constructional arrangements of microphones, e.g. in dummy heads
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04S—STEREOPHONIC SYSTEMS
- H04S1/00—Two-channel systems
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Abstract
Maniquí acústico virtual para la toma de sonido biaural.#Sistema de audición biaural artificial para toma de sonido biaural, comprendiendo dos pabellones auriculares artificiales (1) de posición ajustable; un micrófono omnidireccional acoplado en el pabellón auditivo de cada pabellón auricular artificial y un sistema de procesamiento digital de señal para procesar las señales sonoras captadas por los micrófonos. El sistema de audición biaural artificial (dummy ears) permite capturar la espacialidad del campo sonoro, como lo hace un maniquí acústico (dummy head), pero utilizando únicamente los pabellones auriculares y eliminando toda la estructura cabeza-torso del maniquí.Virtual acoustic mannequin for biaural sound taking. # Artificial biaural hearing system for biaural sound taking, comprising two artificial ear pavilions (1) with adjustable position; an omnidirectional microphone attached to the auditory pavilion of each artificial ear pavilion and a digital signal processing system to process the sound signals picked up by the microphones. The artificial biaural hearing system (dummy ears) allows capturing the spatiality of the sound field, as does an acoustic dummy (dummy head), but using only the ear pavilions and eliminating the entire head-torso structure of the dummy.
Description
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DESCRIPCIONDESCRIPTION
Maniqu acustico virtual para la toma de sonido biaural SECTOR TECNICOVirtual acoustic mannequin for biaural sound capture SECTOR TECNICO
La presente invention se relaciona, en general, con el audio, con todos los derivados de aplicacion de la grabacion sonora y, mas en concreto, con la captura de la espacialidad del campo sonoro y la reproduction biaural. Algunos ejemplos son: industria musical, postproduccion, cine, videojuegos, multimedia, smtesis de espacios sonoros, mezcla con auriculares, etc.The present invention relates, in general, to the audio, with all the derivatives of the application of the sound recording and, more specifically, with the capture of the spatiality of the sound field and the biaural reproduction. Some examples are: music industry, postproduction, cinema, video games, multimedia, sound space synthesis, mixing with headphones, etc.
ANTECEDENTES DE LA INVENCIONBACKGROUND OF THE INVENTION
El sonido que procesa el sistema perceptual humano llega a traves de un sistema biaural modelado comunmente mediante la funcion de transferencia de la cabeza (HRTF, Head- Related Transfer Function). La captura de sonido biaural con un sistema cabeza-torso (en ingles: dummy head) permite posteriormente conseguir la reproduccion mas o menos fiel del campo sonoro; la perception del oyente con auriculares es "tal como si estuviera en el lugar y en el entorno” en el que se grabo. Esto es asi porque el simulador de cabeza-torso (maniqu acustico) modela las reflexiones, absorciones y difracciones del sonido en el receptor de la manera mas fiel a las que experimenta una persona media. Sus propiedades fisicas (dimensiones, materiales, peso, constitution, forma, detalles, etc.) son similares a las de una persona "media”. Esto, evidentemente supone una gran simplification, ya que todos estos atributos tienen valores diferentes para cada persona, pero genera unas cualidades perceptualmente aceptables. Los sistemas cabeza-torso son normalmente muy costosos, pesados y delicados para transportar puesto que depositan todas sus prestaciones en la materialidad de la estructura.The sound processed by the human perceptual system comes through a biaural system commonly modeled by the head transfer function (HRTF). The biaural sound capture with a head-torso system (in English: dummy head) allows later to obtain the more or less faithful reproduction of the sound field; the perception of the listener with headphones is "as if he were in the place and in the environment" in which he recorded. This is so because the head-torso simulator (acoustic mannequin) models the reflections, absorptions and diffractions of the sound in the receiver in the most faithful way to which an average person experiences.Its physical properties (dimensions, materials, weight, constitution, shape, details, etc.) are similar to those of an "average" person. This obviously implies a great simplification, since all these attributes have different values for each person, but it generates perceptually acceptable qualities. The head-torso systems are normally very expensive, heavy and delicate to transport since they deposit all their benefits in the materiality of the structure.
Los maniquis acusticos, integran simuladores de oido (pabellon y canal interno auditivo) para medir o grabar la senal de audio equivalente a la percibida por el ser humano, ya sea procedente de un medio electronico (audifono o auriculares) o recibida directamente del campo sonoro del entorno. Existen varios tipos:The acoustic dummies integrate ear simulators (pavilion and internal auditory channel) to measure or record the audio signal equivalent to that perceived by the human being, either from an electronic medium (earphone or headphones) or received directly from the sound field of the environment. There is a lot of types:
• Simuladores de cabeza y torso que incluyen el simulador de oido completo (pabellon y canal interno auditivo). Estan pensados principalmente para medir la respuesta• Head and torso simulators that include the complete ear simulator (pavilion and internal auditory canal). They are designed primarily to measure the response
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acustica de aud^fonos y auriculares. Entre estos se encuentran los modelos de Kemar (Knowles Electronics Inc.), Head Acoustics HMS II.4 y Cortex Instruments Binaural Recording Head (Mk1 y Mk2).acoustics of headphones and headphones. Among these are the Kemar (Knowles Electronics Inc.), Head Acoustics HMS II.4 and Cortex Instruments Binaural Recording Head (Mk1 and Mk2) models.
• Simuladores de cabeza y torso que incluyen el simulador de oido completo (pabellon y canal interno auditivo) y ademas incorporan una boca artificial (voz artificial). Estan destinados a realizar medidas de dispositivos de comunicacion con auriculares y microfono (telefoma y otros tipos de comunicacion). Ejemplos de estos simuladores son los modelos de Bruel & Kjaer 4128C y de Head Acoustics HMS II.3.• Head and torso simulators that include the complete ear simulator (pavilion and internal auditory canal) and also incorporate an artificial mouth (artificial voice). They are intended to perform measurements of communication devices with headphones and microphone (telephone and other types of communication). Examples of these simulators are the Bruel & Kjaer 4128C and Head Acoustics HMS II.3 models.
• Simuladores de cabeza y torso que incluyen el simulador de oido parcial (solo pabellon auditivo). El microfono de medida bloquea el canal auditivo. Su uso esta pensado para realizar grabaciones de sonido biaurales. El modelo de Bruel & Kjaer 4100 y el de Head Acoustics HMS III son un ejemplo de este tipo de medidas.• Head and torso simulators that include the partial ear simulator (auditory pavilion only). The measurement microphone blocks the ear canal. Its use is designed to make biaural sound recordings. The Bruel & Kjaer 4100 model and the Head Acoustics HMS III model are an example of this type of measurement.
Existen tres estandares que especifican las caracteristicas fisicas y acusticas que han de tener los simuladores de torso y cabeza. Estos son: ANSI S3.36 (Manikin for simulated in- situ airborne acoustic measurements), IEC TR 60959 (Provisional head and torso simulator for acoustic measurements on air conduction hearing aids) e ITU-T P.58 (Head and torso simulator for telephonometry).There are three standards that specify the physical and acoustic characteristics that the torso and head simulators must have. These are: ANSI S3.36 (Manikin for simulated in situ airborne acoustic measurements), IEC TR 60959 (Provisional head and torso simulator for acoustic measurements on air conduction hearing aids) and ITU-T P.58 (Head and torso simulator for telephonometry).
El estandar ANSI S3.36 especifica unas dimensiones fisicas que se corresponden con el maniqu acustico Kemar. Ademas incluye el estandar ANSI S3.25 (American National Standard for an occluded ear simulator) que fija las caracteristicas del simulador de oido (pabellon y canal auditivo).The ANSI S3.36 standard specifies physical dimensions that correspond to the Kemar acoustic dummy. It also includes the ANSI S3.25 standard (American National Standard for an occluded ear simulator) that sets the characteristics of the ear simulator (pavilion and ear canal).
El estandar IEC TR 60959 establece unas dimensiones identicas al estandar anterior ANSI S3.36 pero el simulador de oido (pabellon auditivo sin canal) sigue las especificaciones del estandar IEC 60711 (Occluded-ear simulator for the measurement of earphones coupled to the ear by ear inserts).The IEC TR 60959 standard establishes dimensions identical to the previous ANSI S3.36 standard but the ear simulator (auditory pavilion without channel) follows the specifications of the IEC 60711 standard (Occluded-ear simulator for the measurement of earphones coupled to the ear by ear inserts)
Las dimensiones reflejadas en el estandar ITU-T P.58 son algo diferentes de los otros dos estandares. Coinciden con las de los simuladores de torso y cabeza comerciales de Bruel & Kjaer 4128C y Head Acoustics HMS II.3. El oido artificial del ITU-T P.58 sigue el estandar ITU-T P.57. Establece varios modelos: el tipo 2 (pabellon sin canal auditivo -occluded ear- que coincide con el estandar IEC 60711) y los tipos 3.1, 3.2, 3.3 y 3.4 (pabellones auditivos de dimensiones diferentes -con canal interno-, de acuerdo al tipo de medida requerida).The dimensions reflected in the ITU-T P.58 standard are somewhat different from the other two standards. They match those of the commercial torso and head simulators of Bruel & Kjaer 4128C and Head Acoustics HMS II.3. The artificial ear of ITU-T P.58 follows the ITU-T P.57 standard. It establishes several models: type 2 (pavilion without ear canal -cluded ear- that matches the standard IEC 60711) and types 3.1, 3.2, 3.3 and 3.4 (auditory pavilions of different dimensions -with internal channel-, according to the type of required measure).
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Los tres estandares (ANSI S3.36, IEC TR 60959 e ITU-T P.58) definen tambien la funcion de transferencia acustica de la cabeza (HRTF -Head Related Transfer Function-). En los estandares ANSI S3.36 e IEC TR 60959 la HRTF puede considerarse identica y se refiere al nivel de presion sonora (SPL -Sound Pressure Level-) existente en el timpano con respecto al SPL en campo libre (sin maniqu acustico) en el punto central interno de la cabeza. En el estandar ITU-T P.58 la HRTF se refiere al SPL en el timpano respecto al SPL en campo libre (sin cabeza) pero solo en la posicion 0° de azimut; en cambio, si se gira el maniqu acustico (90°, 180° y 270°) la HRTF se refiere al SPL en el timpano respecto al SPL a 0° de azimut (sin girar).The three standards (ANSI S3.36, IEC TR 60959 and ITU-T P.58) also define the head acoustic transfer function (HRTF -Head Related Transfer Function-). In the ANSI S3.36 and IEC TR 60959 standards the HRTF can be considered identical and refers to the sound pressure level (SPL-Sound Pressure Level-) existing in the tympanum with respect to the SPL in free field (without acoustic dummy) in the internal center point of the head. In the ITU-T P.58 standard, the HRTF refers to the SPL in the tympanum with respect to the SPL in free field (without head) but only in the 0 ° position of azimuth; on the other hand, if the acoustic dummy (90 °, 180 ° and 270 °) is turned, the HRTF refers to the SPL in the tympanum with respect to the SPL at 0 ° azimuth (without turning).
Mas del 95% de la information direccional que el cerebro necesita depende del diseno del pabellon auricular y de la distancia inter-aural. Sin embargo, no existen en la actualidad dispositivos que permitan la adaptation de estos dos parametros para mejorar las medidas en casos en los que por ejemplo, los atributos de la persona disten de la persona media.More than 95% of the directional information that the brain needs depends on the design of the auricular pavilion and the inter-aural distance. However, there are currently no devices that allow the adaptation of these two parameters to improve measures in cases where, for example, the attributes of the person differ from the average person.
DESCRIPCION DE LA INVENCIONDESCRIPTION OF THE INVENTION
La presente invention permite capturar el campo sonoro biaural para una multitud de configuraciones gracias a que permite regular la distancia entre los pabellones auricular y la sustitucion de los mismos. Con este fin, el sistema cabeza-torso material, real, es sustituido por un sistema de procesamiento digital de senal inmaterial, virtual. Para simplificar la jerga utilizada en el texto usaremos el termino dummy head para referirnos al sistema cabeza- torso material (antecedente de la invencion) y el termino dummy ears para referirnos al sistema cabeza-torso inmaterial (presente invencion).The present invention makes it possible to capture the biaural sound field for a multitude of configurations thanks to the fact that it allows to regulate the distance between the auricular pavilions and their replacement. To this end, the real material head-torso system is replaced by a virtual, immaterial, virtual signal processing system. To simplify the jargon used in the text we will use the term dummy head to refer to the material head-torso system (antecedent of the invention) and the term dummy ears to refer to the immaterial head-torso system (present invention).
Los pabellones auriculares son moldeados con una impresora 3D para que reproduzcan la complejidad morfologica del oido externo y constituyan, conjuntamente con el sistema mecanico de acoplamiento, el unico elemento material que interviene directamente en la captura del campo sonoro. En cada pabellon auricular se inserta un microfono omnidireccional. Cada microfono omnidireccional a su vez esta acoplado a un sistema de procesamiento digital de senal encargado de simular las funciones de transferencia, HRTFs.The ear pavilions are molded with a 3D printer to reproduce the morphological complexity of the external ear and, together with the mechanical coupling system, constitute the only material element that directly intervenes in the capture of the sound field. An omnidirectional microphone is inserted into each ear pavilion. Each omnidirectional microphone in turn is coupled to a digital signal processing system in charge of simulating the transfer functions, HRTFs.
La presente invencion tiene las siguientes ventajas sobre el arte previo:The present invention has the following advantages over prior art:
1 El sistema de acoplamiento mecanico de los pabellones auriculares es muy simple y permite regular la distancia biaural.1 The mechanical coupling system of the ear pavilions is very simple and allows to regulate the biaural distance.
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1 El sistema dummy ears puede modelar el sistema cabeza-torso real de cualquier individuo; a diferencia del sistema dummy head que solo admite una configuration fija de todos sus atributos.1 The dummy ears system can model the real head-torso system of any individual; unlike the dummy head system that only supports a fixed configuration of all its attributes.
1 Admite cualquier tipo de pabellon auricular.1 Supports any type of headset.
1 Es de bajo coste (de orden 100 veces inferior).1 It is low cost (of order 100 times lower).
BREVE DESCRIPCION DE LOS DIBUJOSBRIEF DESCRIPTION OF THE DRAWINGS
A continuation se pasa a describir, de manera muy breve, una figura que ayudan a comprender mejor la invention y que se relaciona expresamente con una realization de dicha invencion que se presenta como un ejemplo no limitativo de esta.Next, a figure that helps to better understand the invention and that is expressly related to an embodiment of said invention that is presented as a non-limiting example of this is described very briefly.
La Figura 1 es un diagrama que muestra las partes fundamentales del sistema biaural artificial de la invencion (dummy ears) y donde la cabeza y el torso del arte previo aparecen superpuestos.Figure 1 is a diagram showing the fundamental parts of the artificial biaural system of the invention (dummy ears) and where the head and torso of the prior art appear superimposed.
DESCRIPCION DE UNA REALIZACION PREFERIDADESCRIPTION OF A PREFERRED EMBODIMENT
Segun se ilustra en la Figura 1, se puede apreciar el sistema de acuerdo a la presente invencion con dos pabellones auriculares (1), un microfono insertado en el pabellon auditivo de cada pabellon auricular (2), un sistema regulation de distancia biaural (3) y un sistema de procesado digital de senal (4) que provee una salida de sonido para auriculares. La invencion puede estar dotada ademas de un sistema de regulacion de rotation y de altura.As illustrated in Figure 1, the system according to the present invention can be seen with two ear pavilions (1), a microphone inserted in the ear pavilion of each ear pavilion (2), a biaural distance regulation system (3 ) and a digital signal processing system (4) that provides a sound output for headphones. The invention may also be provided with a rotation and height adjustment system.
La presente invencion consiste en un sistema cabeza-torso virtual, dummy ears, configurable que simula un sistema cabeza-torso real, dummy head, que comprende:The present invention consists of a virtual head-torso system, dummy ears, configurable that simulates a real head-torso system, dummy head, comprising:
1 dos pabellones auriculares impresos 3D (1) que admite diversos materiales (duros y blandos) y que simula la morfologia de un oido externo “conventional”.1 two 3D printed earbuds (1) that supports various materials (hard and soft) and simulates the morphology of a “conventional” external ear.
1 dos microfonos omnidireccionales.1 two omnidirectional microphones.
1 sistema de procesamiento digital que trata la senal capturada mediante las funciones de transferencia acustica (HRTF).1 digital processing system that treats the signal captured by the acoustic transfer functions (HRTF).
Modos de operacionModes of operation
La configuration del dispositivo previa a la operacion con la senal capturada se puede realizar de diversas maneras:The configuration of the device prior to the operation with the captured signal can be done in several ways:
5 - mediante el modelado fisico del sistema cabeza-torso, del que resulta un par de funciones5 - through the physical modeling of the head-torso system, which results in a couple of functions
de de transferencia acusticas (HRTFs). Se podria decir que, independientemente de la tecnica de modelado, se trata de una estimation teorica de las HRTFs (conocido en el estado de la tecnica como modo parametrico).Acoustic transfer (HRTFs). It could be said that, regardless of the modeling technique, it is a theoretical estimation of the HRTFs (known in the state of the art as a parametric mode).
10 -mediante la medida de las HRTFs de un sistema cabeza-torso cualquiera (mediante un metodo de identification de sistemas adaptativo); es decir, la medida de un sistema del cual se desconoce su modelo teorico pero se dispone de su implementation practica. Se podria decir que, independientemente de la tecnica de medida, se trata de una estimacion practica de las HRTFs (metodo conocido en el estado de la tecnica como modo no parametrico).10 -through the measurement of the HRTFs of any head-torso system (by means of an adaptive systems identification method); that is, the measure of a system whose theoretical model is unknown but its practical implementation is available. It could be said that, regardless of the measurement technique, it is a practical estimate of the HRTFs (method known in the state of the art as a non-parametric mode).
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Una vez definidas en el modo anterior las HRTFS (una por cada pabellon auricular), el sistema de procesamiento digital simula las HRTFs del maniqu acustico mediante procesos convolutivos. Este procesamiento de la senal capturada corresponde con la medida acustica en una sala determinada.Once HRTFS has been defined in the previous mode (one for each pavilion), the digital processing system simulates the HRTFs of the acoustic mannequin through convolutive processes. This processing of the captured signal corresponds to the acoustic measurement in a given room.
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| US6223090B1 (en) * | 1998-08-24 | 2001-04-24 | The United States Of America As Represented By The Secretary Of The Air Force | Manikin positioning for acoustic measuring |
| US20040101815A1 (en) * | 2002-11-27 | 2004-05-27 | Jay Mark A. | Biofidelic seating apparatus with binaural acoustical sensing |
| DE102006018490B4 (en) * | 2006-04-19 | 2008-05-08 | Ahnert, Wolfgang, Prof. Dr.-Ing.habil. | Method for the binaural reproduction of acoustic signals |
| JP2009260574A (en) * | 2008-04-15 | 2009-11-05 | Sony Ericsson Mobilecommunications Japan Inc | Sound signal processing device, sound signal processing method and mobile terminal equipped with the sound signal processing device |
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