Facebook Patent | Virtual Microphone
Patent: Virtual Microphone
Publication Number: 20200137488
Publication Date: 20200430
Applicants: Facebook
Abstract
The disclosed computer-implemented method may include establishing and implementing a virtual microphone. The method may include receiving an input specifying a location for a virtual microphone that is configured to capture audio as if located in the specified location. The method may next include initializing physical microphones to begin capturing audio as if located at the specified location. The physical microphones may be electronically or physically oriented to listen from the specified location. The method may then include combining audio streams from the physical microphones to generate a combined audio signal that sounds as if recorded at the specified location. Various other methods, systems, and computer-readable media are also disclosed.
BACKGROUND
[0001] Mobile electronic devices are ubiquitous in today’s world. Users can use these mobile electronic devices to perform a wide variety of functions. For instance, smart phones allow users to make phone or video calls over cellular or WiFi networks. Smart phones include microphones that detect the user’s voice (and other surrounding audio) and convert the user’s voice into an audio signal. This audio signal may then be transmitted to a receiving user’s phone. Microphones on such devices may be used for phone calls but may also be used for other applications including dictation or language translation. Even in these applications, however, the microphone merely detects sounds coming from a sound source and provides the resulting audio signal to a processor for further processing.
SUMMARY
[0002] As will be described in greater detail below, the instant disclosure describes methods and systems that may establish a virtual microphone at a specified location. The virtual microphone may use multiple physical microphones at potentially different locations to record an audio signal as if it were recorded from the specified location.
[0003] In one example, a computer-implemented method for establishing and implementing a virtual microphone may include receiving an input specifying a location for a virtual microphone that is configured to capture audio as if located in the specified location. The method may next include initializing physical microphones to begin capturing audio as if located at the specified location. The physical microphones may be electronically or physically oriented to listen from that location. The method may then include combining audio streams from the physical microphones to generate a combined audio signal that sounds as if recorded at the specified location.
[0004] In some examples, the method may further include receiving information relative to an environment, determining that the specified location is within the environment, and implementing the received environment information to customize acoustic characteristics of the specified location. In some examples, the environment information indicates that the specified location is within a building, and may further indicate which part of the building the specified location is in. In some examples, the environment information indicates that people are within a given distance of the specified location, or that a specific person is within a given distance of the specified location.
[0005] In some examples, other mobile devices having microphones that come within a specified distance of the specified location may be initialized to capture audio and provide the captured audio to the combined audio stream. In some examples, the method for establishing and implementing a virtual microphone may further include analyzing the combined audio streams from the physical microphones to identify the presence of people or specific persons that are within audible range of the specified location. In some examples, the virtual microphone may be governed by policies indicating when capturing audio from the virtual microphone is permissible and when not permissible. In some examples, the virtual microphone policies may be geography-based, time-based or individual-based.
[0006] In some examples, the virtual microphone may be activated automatically upon detecting audible sounds within range of the virtual microphone. In some examples, the method may further include taking observations about the specified location. These observations may be stored in a local or distributed data store. In some examples, the two or more physical microphones are at least initially not located at the specified location.
[0007] In some examples, at least one of the physical microphones may be embedded in a mobile device associated with a user. The user may opt in to allow their mobile device to be used as a virtual microphone. In some examples, the user’s opt in may be subject to policies indicating times and locations where their mobile device is usable as a virtual microphone. In some examples, a user-initiated placement of the virtual microphone may be overridden by a location-based policy indicating that virtual microphones are disallowed at the specified location. In such examples, the initialized physical microphones may be disengaged.
[0008] In some examples, the method may further include initializing physical speakers at a specified location. The physical speakers may be electronically or physically oriented to project sound as if coming from the specified location. In some examples, the method may further include associating a sequence of actions with the specified location, so that when a user is detected in the specified location, the sequence of actions is carried out. In some examples, the sequence of actions may take place at a scheduled time.
[0009] In addition, a corresponding system for establishing and implementing a virtual microphone may include several modules stored in memory, including an input receiving module configured to receive an input specifying a location for a virtual microphone that is configured to capture audio as if located in the specified location. The system may also include a hardware initialization module configured to initialize physical microphones to begin capturing audio as if located at the specified location. The physical microphones may be electronically or physically oriented to listen from the specified location. The system may also include an audio stream processor configured to combine audio streams from the physical microphones to generate a combined audio signal that sounds as if recorded at the specified location.
[0010] In some examples, the above-described method may be encoded as computer-readable instructions on a computer-readable medium. For example, a computer-readable medium may include one or more computer-executable instructions that, when executed by at least one processor of a computing device, may cause the computing device to receive an input specifying a location for a virtual microphone that is configured to capture audio as if located in the specified location, and initialize physical microphones to begin capturing audio as if located at the specified location. The physical microphones may be electronically or physically oriented to listen from the specified location. The computing device may also combine audio streams from the physical microphones to generate a combined audio signal that sounds as if recorded at the specified location.
[0011] Features from any of the above-mentioned embodiments may be used in combination with one another in accordance with the general principles described herein. These and other embodiments, features, and advantages will be more fully understood upon reading the following detailed description in conjunction with the accompanying drawings and claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The accompanying drawings illustrate a number of exemplary embodiments and are a part of the specification. Together with the following description, these drawings demonstrate and explain various principles of the instant disclosure.
[0013] FIG. 1 illustrates an embodiment of an artificial reality headset.
[0014] FIG. 2 illustrates an embodiment of an augmented reality headset and corresponding neckband.
[0015] FIG. 3 illustrates an embodiment of a virtual reality headset.
[0016] FIG. 4 illustrates an embodiment of a computing architecture in which the embodiments herein may operate.
[0017] FIG. 5 illustrates a flow diagram of an exemplary method for initializing and operating a virtual microphone.
[0018] FIG. 6 illustrates an embodiment in which multiple electronic devices are used to create a virtual microphone.
[0019] FIG. 7 illustrates an alternative embodiment in which multiple electronic devices are used to create a virtual microphone.
[0020] FIG. 8 illustrates an embodiment in which virtual microphones are allowed or disallowed.
[0021] FIG. 9 illustrates an embodiment in which speakers are directed to a specification to sound as if originating from that location.
[0022] FIG. 10 illustrates an embodiment in which a sequence of actions takes place when a user is detected in a specified location.
[0023] Throughout the drawings, identical reference characters and descriptions indicate similar, but not necessarily identical, elements. While the exemplary embodiments described herein are susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and will be described in detail herein. However, the exemplary embodiments described herein are not intended to be limited to the particular forms disclosed. Rather, the instant disclosure covers all modifications, equivalents, and alternatives falling within the scope of the appended claims.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0024] The present disclosure is generally directed to systems and methods for initializing and operating a virtual microphone. As will be explained in greater detail below, embodiments of the instant disclosure may establish a virtual microphone at a specified location. The virtual microphone may use physical microphones from other electronic devices (e.g., phones or artificial reality devices) that are near the specified location. The electronic devices may be configured to direct the focus of their microphones to the specified location, and then capture audio as if the microphones were actually located at the specified location. The virtual microphone may use substantially any microphones from any devices that come within range of the specified location. In some cases, virtual microphone functionality may be regulated by policies and may be disallowed by default unless specifically opted into by a user.
[0025] In one embodiment, users may be wearing artificial headsets in an indoor or outdoor environment. These users may wish to record audio from a specified location without necessarily placing a physical microphone in that location. As such, a user may establish a virtual microphone by specifying a location and initializing at least two physical microphones configured to listen from that location. The audio feeds from the two microphones may then be combined into a single audio stream that sounds as if recorded at the specified location.
[0026] As users wander about the environment, their artificial reality headsets and/or phones may come into range of the specified location. If opted in, the microphone(s) in the users’ artificial reality headsets, phones or other devices may be initialized and pointed at the specified location. As such, the microphones in the users’ mobile devices may each record audio as if from the specified location, and provide those audio streams to a single device, or to a remote server (e.g., a cloud server) for processing. This processing may combine the audio feeds into a single feed that sounds as if recorded at the specified location. Once a user’s mobile device is out of range of the specified location, the microphones on that user’s device may be turned off, and that user’s device will no longer be contributing to the virtual microphone.
[0027] Embodiments of the instant disclosure may include or be implemented in conjunction with various types of artificial reality systems. Artificial reality is a form of reality that has been adjusted in some manner before presentation to a user, which may include, e.g., a virtual reality (VR), an augmented reality (AR), a mixed reality (MR), a hybrid reality, or some combination and/or derivative thereof. Artificial reality content may include completely generated content or generated content combined with captured (e.g., real-world) content. The artificial reality content may include video, audio, haptic feedback, or some combination thereof, any of which may be presented in a single channel or in multiple channels (such as stereo video that produces a three-dimensional effect to the viewer). Additionally, in some embodiments, artificial reality may also be associated with applications, products, accessories, services, or some combination thereof, that are used to, e.g., create content in an artificial reality and/or are otherwise used in (e.g., to perform activities in) an artificial reality.
[0028] Artificial reality systems may be implemented in a variety of different form factors and configurations. Some artificial reality systems may be designed to work without near-eye displays (NEDs), an example of which is AR system 100 in FIG. 1. Other artificial reality systems may include an NED that also provides visibility into the real world (e.g., AR system 200 in FIG. 2) or that visually immerses a user in an artificial reality (e.g., VR system 300 in FIG. 3). While some artificial reality devices may be self-contained systems, other artificial reality devices may communicate and/or coordinate with external devices to provide an artificial reality experience to a user. Examples of such external devices include handheld controllers, mobile devices, desktop computers, devices worn by a user, devices worn by one or more other users, and/or any other suitable external system.
[0029] Turning to FIG. 1, AR system 100 generally represents a wearable device dimensioned to fit about a body part (e.g., a head) of a user. As shown in FIG. 1, system 100 may include a frame 102 and a camera assembly 104 that is coupled to frame 102 and configured to gather information about a local environment by observing the local environment. AR system 100 may also include one or more audio devices, such as output audio transducers 108(A) and 108(B) and input audio transducers 110. Output audio transducers 108(A) and 108(B) may provide audio feedback and/or content to a user, and input audio transducers 110 may capture audio in a user’s environment.
[0030] As shown, AR system 100 may not necessarily include an NED positioned in front of a user’s eyes. AR systems without NEDs may take a variety of forms, such as head bands, hats, hair bands, belts, watches, wrist bands, ankle bands, rings, neckbands, necklaces, chest bands, eyewear frames, and/or any other suitable type or form of apparatus. While AR system 100 may not include an NED, AR system 100 may include other types of screens or visual feedback devices (e.g., a display screen integrated into a side of frame 102).
[0031] The embodiments discussed in this disclosure may also be implemented in AR systems that include one or more NEDs. For example, as shown in FIG. 2, AR system 200 may include an eyewear device 202 with a frame 210 configured to hold a left display device 215(A) and a right display device 215(B) in front of a user’s eyes. Display devices 215(A) and 215(B) may act together or independently to present an image or series of images to a user. While AR system 200 includes two displays, embodiments of this disclosure may be implemented in AR systems with a single NED or more than two NEDs.
[0032] In some embodiments, AR system 200 may include one or more sensors, such as sensor 240. Sensor 240 may generate measurement signals in response to motion of AR system 200 and may be located on substantially any portion of frame 210. Sensor 240 may include a position sensor, an inertial measurement unit (IMU), a depth camera assembly, or any combination thereof. In some embodiments, AR system 200 may or may not include sensor 240 or may include more than one sensor. In embodiments in which sensor 240 includes an IMU, the IMU may generate calibration data based on measurement signals from sensor 240. Examples of sensor 240 may include, without limitation, accelerometers, gyroscopes, magnetometers, other suitable types of sensors that detect motion, sensors used for error correction of the IMU, or some combination thereof.
[0033] AR system 200 may also include a microphone array with a plurality of acoustic sensors 220(A)-220(J), referred to collectively as acoustic sensors 220. Acoustic sensors 220 may be transducers that detect air pressure variations induced by sound waves. Each acoustic sensor 220 may be configured to detect sound and convert the detected sound into an electronic format (e.g., an analog or digital format). The microphone array in FIG. 2 may include, for example, ten acoustic sensors: 220(A) and 220(B), which may be designed to be placed inside a corresponding ear of the user, acoustic sensors 220(C), 220(D), 220(E), 220(F), 220(G), and 220(H), which may be positioned at various locations on frame 210, and/or acoustic sensors 220(I) and 220(J), which may be positioned on a corresponding neckband 205.
[0034] The configuration of acoustic sensors 220 of the microphone array may vary. While AR system 200 is shown in FIG. 2 as having ten acoustic sensors 220, the number of acoustic sensors 220 may be greater or less than ten. In some embodiments, using higher numbers of acoustic sensors 220 may increase the amount of audio information collected and/or the sensitivity and accuracy of the audio information. In contrast, using a lower number of acoustic sensors 220 may decrease the computing power required by the controller 250 to process the collected audio information. In addition, the position of each acoustic sensor 220 of the microphone array may vary. For example, the position of an acoustic sensor 220 may include a defined position on the user, a defined coordinate on the frame 210, an orientation associated with each acoustic sensor, or some combination thereof.
[0035] Acoustic sensors 220(A) and 220(B) may be positioned on different parts of the user’s ear, such as behind the pinna or within the auricle or fossa. Or, there may be additional acoustic sensors on or surrounding the ear in addition to acoustic sensors 220 inside the ear canal. Having an acoustic sensor positioned next to an ear canal of a user may enable the microphone array to collect information on how sounds arrive at the ear canal. By positioning at least two of acoustic sensors 220 on either side of a user’s head (e.g., as binaural microphones), AR device 200 may simulate binaural hearing and capture a 3D stereo sound field around about a user’s head. In some embodiments, the acoustic sensors 220(A) and 220(B) may be connected to the AR system 200 via a wired connection, and in other embodiments, the acoustic sensors 220(A) and 220(B) may be connected to the AR system 200 via a wireless connection (e.g., a Bluetooth connection). In still other embodiments, the acoustic sensors 220(A) and 220(B) may not be used at all in conjunction with the AR system 200.
[0036] Acoustic sensors 220 on frame 210 may be positioned along the length of the temples, across the bridge, above or below display devices 215(A) and 215(B), or some combination thereof. Acoustic sensors 220 may be oriented such that the microphone array is able to detect sounds in a wide range of directions surrounding the user wearing the AR system 200. In some embodiments, an optimization process may be performed during manufacturing of AR system 200 to determine relative positioning of each acoustic sensor 220 in the microphone array.
[0037] AR system 200 may further include or be connected to an external device. (e.g., a paired device), such as neckband 205. As shown, neckband 205 may be coupled to eyewear device 202 via one or more connectors 230. The connectors 230 may be wired or wireless connectors and may include electrical and/or non-electrical (e.g., structural) components. In some cases, the eyewear device 202 and the neckband 205 may operate independently without any wired or wireless connection between them. While FIG. 2 illustrates the components of eyewear device 202 and neckband 205 in example locations on eyewear device 202 and neckband 205, the components may be located elsewhere and/or distributed differently on eyewear device 202 and/or neckband 205. In some embodiments, the components of the eyewear device 202 and neckband 205 may be located on one or more additional peripheral devices paired with eyewear device 202, neckband 205, or some combination thereof. Furthermore, neckband 205 generally represents any type or form of paired device. Thus, the following discussion of neckband 205 may also apply to various other paired devices, such as smart watches, smart phones, wrist bands, other wearable devices, hand-held controllers, tablet computers, laptop computers, etc.
[0038] Pairing external devices, such as neckband 205, with AR eyewear devices may enable the eyewear devices to achieve the form factor of a pair of glasses while still providing sufficient battery and computation power for expanded capabilities. Some or all of the battery power, computational resources, and/or additional features of AR system 200 may be provided by a paired device or shared between a paired device and an eyewear device, thus reducing the weight, heat profile, and form factor of the eyewear device overall while still retaining desired functionality. For example, neckband 205 may allow components that would otherwise be included on an eyewear device to be included in neckband 205 since users may tolerate a heavier weight load on their shoulders than they would tolerate on their heads. Neckband 205 may also have a larger surface area over which to diffuse and disperse heat to the ambient environment. Thus, neckband 205 may allow for greater battery and computation capacity than might otherwise have been possible on a stand-alone eyewear device. Since weight carried in neckband 205 may be less invasive to a user than weight carried in eyewear device 202, a user may tolerate wearing a lighter eyewear device and carrying or wearing the paired device for greater lengths of time than the user would tolerate wearing a heavy standalone eyewear device, thereby enabling an artificial reality environment to be incorporated more fully into a user’s day-to-day activities.
[0039] Neckband 205 may be communicatively coupled with eyewear device 202 and/or to other devices. The other devices may provide certain functions (e.g., tracking, localizing, depth mapping, processing, storage, etc.) to the AR system 200. In the embodiment of FIG. 2, neckband 205 may include two acoustic sensors (e.g., 220(I) and 220(J)) that are part of the microphone array (or potentially form their own microphone subarray). Neckband 205 may also include a controller 225 and a power source 235.
[0040] Acoustic sensors 220(I) and 220(J) of neckband 205 may be configured to detect sound and convert the detected sound into an electronic format (analog or digital). In the embodiment of FIG. 2, acoustic sensors 220(I) and 220(J) may be positioned on neckband 205, thereby increasing the distance between the neckband acoustic sensors 220(I) and 220(J) and other acoustic sensors 220 positioned on eyewear device 202. In some cases, increasing the distance between acoustic sensors 220 of the microphone array may improve the accuracy of beamforming performed via the microphone array. For example, if a sound is detected by acoustic sensors 220(C) and 220(D) and the distance between acoustic sensors 220(C) and 220(D) is greater than, e.g., the distance between acoustic sensors 220(D) and 220(E), the determined source location of the detected sound may be more accurate than if the sound had been detected by acoustic sensors 220(D) and 220(E).
[0041] Controller 225 of neckband 205 may process information generated by the sensors on neckband 205 and/or AR system 200. For example, controller 225 may process information from the microphone array that describes sounds detected by the microphone array. For each detected sound, controller 225 may perform a DoA estimation to estimate a direction from which the detected sound arrived at the microphone array. As the microphone array detects sounds, controller 225 may populate an audio data set with the information. In embodiments in which AR system 200 includes an inertial measurement unit, controller 225 may compute all inertial and spatial calculations from the IMU located on eyewear device 202. Connector 230 may convey information between AR system 200 and neckband 205 and between AR system 200 and controller 225. The information may be in the form of optical data, electrical data, wireless data, or any other transmittable data form. Moving the processing of information generated by AR system 200 to neckband 205 may reduce weight and heat in eyewear device 202, making it more comfortable to the user.
[0042] Power source 235 in neckband 205 may provide power to eyewear device 202 and/or to neckband 205. Power source 235 may include, without limitation, lithium ion batteries, lithium-polymer batteries, primary lithium batteries, alkaline batteries, or any other form of power storage. In some cases, power source 235 may be a wired power source. Including power source 235 on neckband 205 instead of on eyewear device 202 may help better distribute the weight and heat generated by power source 235.
[0043] As noted, some artificial reality systems may, instead of blending an artificial reality with actual reality, substantially replace one or more of a user’s sensory perceptions of the real world with a virtual experience. One example of this type of system is a head-worn display system, such as VR system 300 in FIG. 3, that mostly or completely covers a user’s field of view. VR system 300 may include a front rigid body 302 and a band 304 shaped to fit around a user’s head. VR system 300 may also include output audio transducers 306(A) and 306(B). Furthermore, while not shown in FIG. 3, front rigid body 302 may include one or more electronic elements, including one or more electronic displays, one or more inertial measurement units (IMUS), one or more tracking emitters or detectors, and/or any other suitable device or system for creating an artificial reality experience.
[0044] Artificial reality systems may include a variety of types of visual feedback mechanisms. For example, display devices in AR system 200 and/or VR system 300 may include one or more liquid crystal displays (LCDs), light emitting diode (LED) displays, organic LED (OLED) displays, and/or any other suitable type of display screen. Artificial reality systems may include a single display screen for both eyes or may provide a display screen for each eye, which may allow for additional flexibility for varifocal adjustments or for correcting a user’s refractive error. Some artificial reality systems may also include optical subsystems having one or more lenses (e.g., conventional concave or convex lenses, Fresnel lenses, adjustable liquid lenses, etc.) through which a user may view a display screen.
[0045] In addition to or instead of using display screens, some artificial reality systems may include one or more projection systems. For example, display devices in AR system 200 and/or VR system 300 may include micro-LED projectors that project light (using, e.g., a waveguide) into display devices, such as clear combiner lenses that allow ambient light to pass through. The display devices may refract the projected light toward a user’s pupil and may enable a user to simultaneously view both artificial reality content and the real world. Artificial reality systems may also be configured with any other suitable type or form of image projection system.
[0046] Artificial reality systems may also include various types of computer vision components and subsystems. For example, AR system 100, AR system 200, and/or VR system 300 may include one or more optical sensors such as two-dimensional (2D) or three-dimensional (3D) cameras, time-of-flight depth sensors, single-beam or sweeping laser rangefinders, 3D LiDAR sensors, and/or any other suitable type or form of optical sensor. An artificial reality system may process data from one or more of these sensors to identify a location of a user, to map the real world, to provide a user with context about real-world surroundings, and/or to perform a variety of other functions.
[0047] Artificial reality systems may also include one or more input and/or output audio transducers. In the examples shown in FIGS. 1 and 3, output audio transducers 108(A), 108(B), 306(A), and 306(B) may include voice coil speakers, ribbon speakers, electrostatic speakers, piezoelectric speakers, bone conduction transducers, cartilage conduction transducers, and/or any other suitable type or form of audio transducer. Similarly, input audio transducers 110 may include condenser microphones, dynamic microphones, ribbon microphones, and/or any other type or form of input transducer. In some embodiments, a single transducer may be used for both audio input and audio output.
[0048] While not shown in FIGS. 1-3, artificial reality systems may include tactile (i.e., haptic) feedback systems, which may be incorporated into headwear, gloves, body suits, handheld controllers, environmental devices (e.g., chairs, floormats, etc.), and/or any other type of device or system. Haptic feedback systems may provide various types of cutaneous feedback, including vibration, force, traction, texture, and/or temperature. Haptic feedback systems may also provide various types of kinesthetic feedback, such as motion and compliance. Haptic feedback may be implemented using motors, piezoelectric actuators, fluidic systems, and/or a variety of other types of feedback mechanisms. Haptic feedback systems may be implemented independent of other artificial reality devices, within other artificial reality devices, and/or in conjunction with other artificial reality devices.
[0049] By providing haptic sensations, audible content, and/or visual content, artificial reality systems may create an entire virtual experience or enhance a user’s real-world experience in a variety of contexts and environments. For instance, artificial reality systems may assist or extend a user’s perception, memory, or cognition within a particular environment. Some systems may enhance a user’s interactions with other people in the real world or may enable more immersive interactions with other people in a virtual world. Artificial reality systems may also be used for educational purposes (e.g., for teaching or training in schools, hospitals, government organizations, military organizations, business enterprises, etc.), entertainment purposes (e.g., for playing video games, listening to music, watching video content, etc.), and/or for accessibility purposes (e.g., as hearing aids, visuals aids, etc.). The embodiments disclosed herein may enable or enhance a user’s artificial reality experience in one or more of these contexts and environments and/or in other contexts and environments.
[0050] Some AR systems may map a user’s environment using techniques referred to as “simultaneous location and mapping” (SLAM). SLAM mapping and location identifying techniques may involve a variety of hardware and software tools that can create or update a map of an environment while simultaneously keeping track of a user’s location within the mapped environment. SLAM may use many different types of sensors to create a map and determine a user’s position within the map.
[0051] SLAM techniques may, for example, implement optical sensors to determine a user’s location. Radios including WiFi, Bluetooth, global positioning system (GPS), cellular or other communication devices may be also used to determine a user’s location relative to a radio transceiver or group of transceivers (e.g., a WiFi router or group of GPS satellites). Acoustic sensors such as microphone arrays or 2D or 3D sonar sensors may also be used to determine a user’s location within an environment. AR and VR devices (such as systems 100, 200, or 300 of FIG. 1, 2 or 3, respectively) may incorporate any or all of these types of sensors to perform SLAM operations such as creating and continually updating maps of the user’s current environment. In at least some of the embodiments described herein, SLAM data generated by these sensors may be referred to as “environmental data” and may indicate a user’s current environment. This data may be stored in a local or remote data store (e.g., a cloud data store) and may be provided to a user’s AR/VR device on demand.
[0052] When the user is wearing an AR headset or VR headset in a given environment, the user may be interacting with other users or other electronic devices that serve as audio sources. In some cases, it may be desirable to determine where the audio sources are located relative to the user and then present the audio sources to the user as if they were coming from the location of the audio source. The process of determining where the audio sources are located relative to the user may be referred to herein as “localization,” and the process of rendering playback of the audio source signal to appear as if it is coming from a specific direction may be referred to herein as “spatialization.”
