Patent Description:
A virtual scene enables a user to move around the virtual scene and to experience content in different ways depending on a virtual location of the user within the scene. There remains a need for alternative arrangements for providing and controlling audio content in virtual scenes.

<CIT> describes an apparatus configured to receive, from first and second spatial audio capture apparatuses, respective first and second composite audio signals comprising components derived from one or more sound sources in a capture space. The apparatus is further configured to identify a position of a user deice corresponding to one of first and second areas respectively associated with the positions of the first and second spatial audio capture apparatuses, and to render audio representing the one or more sound sources to the user device, the rendering being performed differently dependent on, for the spatial audio capture apparatus associated with the identified first or second area, whether or not individual audio signals from each of the one or more sound sources can be successfully separated from its composite signal.

The scope of protection of the invention is defined by the appended claims.

Example embodiments will now be described, by way of example only, with reference to the following schematic drawings, in which:.

The embodiments and features, if any, described in the specification that do not fall under the scope of the independent claims are to be interpreted as examples useful for understanding various embodiments of the invention.

Virtual reality (VR) can generally be understood as a rendered version of visual and/or audio scenes. The rendering may be designed to mimic visual and audio sensory stimuli of the real world in order to provide a natural experience to a user that is at least significantly consistent with their movement within a virtual scene according to the limits defined by the content and/or application.

VR in many cases, but not necessarily all cases, requires a user to wear a head mounted display (HMD), to completely replace the user's field of view with a simulated visual presentation, and to wear headphones, to provide the user the simulated audio content similarly completely replacing the sound scene of the physical space. Some form of head tracking and general motion tracking of the user consuming VR content may also be necessary. This allows the simulated visual and audio presentation to be updated in order to ensure that, from the user's perspective, various scene components such as items and sound sources remain consistent with the user's movements. Additional means to interact with the virtual reality simulation, such as controls or other user interfaces (UI) may be provided but are not strictly necessary for providing the experience.

VR can in some use cases be visual-only or audio-only virtual reality. For example, an audio-only VR experience may relate to a new type of music listening or any other audio experience.

Augmented reality (AR) generally refers to providing user with additional information or artificially generated items or content that is at least significantly overlaid upon the user's current real-world environment stimuli. In some such cases, the augmented content may at least partly replace a real-world content for the user. Additional information or content may be visual and/or audible. AR may have visual-only or audio-only presentation. For example, a user may move about a city and receive audio guidance relating to, e.g., navigation, location-based advertisements, and any other location-based information.

Mixed reality (MR) is sometimes considered as a more advanced form of AR where at least some virtual elements are inserted into the physical scene such that they provide the illusion that these elements are part of the real scene and behave accordingly. For audio content, or indeed audio-only use cases, many applications of AR and MR may appear difficult for the user to tell from one another. However, the difference is not only for visual content but it may be relevant also for audio. For example, MR audio rendering may take into account a local room reverberation, e.g., while AR audio rendering may not.

In a 3D space, there are in total six degrees of freedom (DoF) defining the way the user may move within the space. This movement is divided into two categories: rotational movement and translational movement (with three degrees of freedom each). Rotational movement is sufficient for a simple VR experience where the user may turn his/her head (pitch, yaw, and roll) to experience the space from a static point or along an automatically moving trajectory. Translational movement means that the user may also change the position of the rendering, i.e., move along the x, y, and z axes in Euclidean space according to their wishes. Free-viewpoint AR/VR experiences allow for both rotational and translational movements. It is common to talk about the various degrees of freedom and the related experiences using the terms 3DoF, 3DoF+ and 6DoF. 3DoF+ falls somewhat between 3DoF and 6DoF and typically allows for some limited user movement, e.g., it can be considered to implement a restricted 6DoF where the user is sitting down but can lean their head in various directions.

<FIG> is a block diagram of a virtual reality display system, indicated generally by the reference numeral <NUM>, in which example embodiments may be implemented. The virtual reality display system <NUM> includes a user device in the form of a virtual reality headset <NUM>, for displaying visual data and/or presenting audio data for a virtual reality space, and a virtual reality media player <NUM> for rendering visual and/or audio data on the virtual reality headset <NUM>. In some example embodiments, a separate user control (not shown) may be associated with the virtual reality display system, e.g. a hand-held controller.

A virtual space, world or environment may be a computer-generated version of a space, for example a captured real world space, in which a user can be immersed. In some example embodiments, the virtual space or scene may be entirely computer-generated. The virtual reality headset <NUM> may be of any suitable type. The virtual reality headset <NUM> may be configured to provide virtual reality video and/or audio content data to a user. As such, the user may be immersed in virtual space.

In the example virtual reality display system <NUM>, the virtual reality headset <NUM> receives the virtual reality content data from a virtual reality media player <NUM>. The virtual reality media player <NUM> may be part of a separate device that is connected to the virtual reality headset <NUM> by a wired or wireless connection. For example, the virtual reality media player <NUM> may include a games console, or a PC (Personal Computer) configured to communicate visual data to the virtual reality headset <NUM>.

Alternatively, the virtual reality media player <NUM> may form part of the virtual reality headset <NUM>.

The virtual reality media player <NUM> may comprise a mobile phone, smartphone or tablet computer configured to provide content through its display. For example, the virtual reality media player <NUM> may be a touchscreen device having a large display over a major surface of the device, through which video content can be displayed. The virtual reality media player <NUM> may be inserted into a holder of a virtual reality headset <NUM>. With such virtual reality headsets <NUM>, a smart phone or tablet computer may display visual data which is provided to a user's eyes via respective lenses in the virtual reality headset <NUM>. The virtual reality audio may be presented, e.g., by loudspeakers that are integrated into the virtual reality headset <NUM> or headphones that are connected to it. The virtual reality display system <NUM> may also include hardware configured to convert the device to operate as part of virtual reality display system <NUM>. Alternatively, the virtual reality media player <NUM> may be integrated into the virtual reality headset <NUM>. The virtual reality media player <NUM> may be implemented in software. In some example embodiments, a device comprising virtual reality media player software is referred to as the virtual reality media player <NUM>.

The virtual reality display system <NUM> may include means for determining the spatial position of the user and/or orientation of the user's head. This may be by means of determining the spatial position and/or orientation of the virtual reality headset <NUM>. Over successive time frames, a measure of movement may therefore be calculated and stored. Such means may comprise part of the virtual reality media player <NUM>. Alternatively, the means may comprise part of the virtual reality headset <NUM>. For example, the virtual reality headset <NUM> may incorporate motion tracking sensors which may include one or more of gyroscopes, accelerometers and structured light systems. These sensors generate position data from which a current visual field-of-view (FOV) is determined and updated as the user, and so the virtual reality headset <NUM>, changes position and/or orientation. The virtual reality headset <NUM> may comprise two digital screens for displaying stereoscopic video images of the virtual world in front of respective eyes of the user, and also two headphones, earphone or speakers for delivering audio. The example embodiments herein are not limited to a particular type of virtual reality headset <NUM>.

In some example embodiments, the virtual reality display system <NUM> may determine the spatial position and/or orientation of the user's head using the above-mentioned six degrees-of-freedom method. These may include measurements of pitch, roll and yaw and also translational movement in Euclidean space along side-to-side, front-to-back and up-and-down axes.

The virtual reality display system <NUM> may be configured to display virtual reality content data to the virtual reality headset <NUM> based on spatial position and/or the orientation of the virtual reality headset. A detected change in spatial position and/or orientation, i.e. a form of movement, may result in a corresponding change in the visual and/or audio data to reflect a position or orientation transformation of the user with reference to the space into which the visual data is projected. This allows virtual reality content data to be consumed with the user experiencing a 3D virtual reality environment.

In the context of volumetric virtual reality spaces or worlds, a user's position may be detected relative to content provided within the volumetric virtual reality content, e.g. so that the user can move freely within a given virtual reality space or world, around individual objects or groups of objects, and can view and/or listen to the objects from different angles depending on the rotation of their head.

Audio data may be provided to headphones provided as part of the virtual reality headset <NUM>. The audio data may represent spatial audio source content. Spatial audio may refer to directional rendering of audio in the virtual reality space or world such that a detected change in the user's spatial position or in the orientation of their head may result in a corresponding change in the spatial audio rendering to reflect a transformation with reference to the space in which the spatial audio data is rendered.

<FIG> is a virtual environment, indicated generally by the reference numeral <NUM>, in accordance with an example embodiment. The virtual environment <NUM> may be implemented using the virtual reality display system <NUM> described above. The virtual environment <NUM> shows a user <NUM> and first to third audio sources <NUM> to <NUM>. The user <NUM> may be wearing the virtual reality headset <NUM> described above in order to experience the virtual environment <NUM>.

The virtual environment <NUM> may therefore present a virtual scene (e.g. a virtual reality, mixed reality or augmented reality scene) to the user <NUM>. The scene may, for example, be a three-dimensional virtual reality scene.

The virtual environment <NUM> is a virtual audio scene and the user <NUM> has a position and an orientation within the scene. The audio presented to the user <NUM> (e.g. using the virtual reality headset <NUM>) is dependent on the position and orientation of the user <NUM>, such that a 6DoF scene may be provided.

The first to third audio sources <NUM> to <NUM> may, for example, be used to output a song to the user <NUM>. In one example embodiment, different musical instruments (or audio from different musical instruments) are assigned to different the different audio sources (or tracks) <NUM> to <NUM> of the first audio. Thus, different instruments may be presented at different locations within the virtual environment <NUM> (e.g. such that an "instrument constellation" is provided). Such constellations are particularly suitable for presenting legacy content such as music tracks which are available as multitrack recordings.

6DoF audio provides an audio experience in which the user <NUM> can move within the audio scene. However, providing a full 6DoF content experience may require that the content be specifically spatially arranged and created for 6DoF consumption. Such systems may not be compatible with legacy audio content.

<FIG> is a flow chart showing an algorithm, indicated generally by the reference numeral <NUM>, in accordance with an example embodiment.

The algorithm <NUM> starts at operation <NUM>, where one of a plurality of audio modes for presentation of first audio (e.g. volumetric audio) to a user (e.g. the user <NUM>) is determined. The determination of the audio mode may be based on a location and/or movement of the user within a virtual scene, such as the virtual environment <NUM>. Thus, the first audio is provided within the virtual scene about which the user can move (e.g. with <NUM>-DoF movement). The first audio may include a plurality of audio tracks located at different locations within the virtual scene. The audio sources <NUM> to <NUM> are examples of such audio tracks.

At operation <NUM>, audio is rendered (e.g. to the user <NUM>) in the determined audio mode, i.e. the mode determined in operation <NUM>.

As described in detail below, the audio modes may include a first audio mode in which the locations of the audio tracks within the virtual scene are fixed (such that the user can move relative to the audio tracks) and a second audio mode in which the locations of the audio tracks within the virtual scene move with the user. The first audio mode may be a <NUM>-DoF audio mode. The second audio mode may be a <NUM>-DoF audio mode.

<FIG> is a flow chart showing an algorithm, indicated generally by the reference numeral <NUM>, in accordance with an example embodiment. The algorithm <NUM> is described further below with reference to <FIG>.

The algorithm <NUM> starts with an optional operation <NUM> in which a user (such as the user <NUM>) enters an audio constellation, such as a constellation of audio sources or audio tracks. For example, the first to third audio sources <NUM> to <NUM> may constitute an audio constellation. The operation <NUM> may, for example, involve the selection of a first audio from a plurality of candidate first audios by determining that the user is located, in the virtual scene, within, or within the vicinity of, a constellation of audio tracks of the selected first audio of the plurality of candidate first audios.

In operation <NUM> of the algorithm <NUM>, an audio mode is determined.

<FIG> is a virtual environment, indicated generally by the reference numeral <NUM>, in accordance with an example embodiment. The virtual environment <NUM> includes the user <NUM> and the first to third audio sources <NUM> to <NUM> described above. The virtual environment <NUM> further comprises a first zone <NUM>. As shown in <FIG>, the user <NUM> is outside the first zone <NUM>. That zone may be visible to the user in some way within the virtual environment, for example with different colouring of objects depending on whether the user <NUM> is inside or outside the first zone <NUM> (although this is not essential to all example embodiments).

In the operation <NUM> of the algorithm <NUM>, the determination of the audio mode may be dependent on the location of the user <NUM> relative to the first zone <NUM>. For example, the audio mode selection may be dependent on whether the user <NUM> is outside the first zone <NUM> (as shown in the virtual environment <NUM>) or inside the first zone (as discussed below).

<FIG> is a virtual environment, indicated generally by the reference numeral <NUM>, in accordance with an example embodiment. The virtual environment <NUM> includes the user <NUM>, the first to third audio sources <NUM> to <NUM> and the first zone <NUM> described above. In the virtual environment <NUM>, the user <NUM> is approaching the first zone from outside said zone.

In operation <NUM> of the algorithm <NUM>, the first audio mode is initiated. The operation <NUM> may initiate the first audio mode when the user approaches (e.g. makes contact with) the first zone <NUM>, as shown in the virtual environment <NUM>.

In operation <NUM> of the algorithm <NUM>, the first zone <NUM> is positioned within the virtual space, on initiation of the first audio mode, such that the user <NUM> is at a central point of said first zone.

<FIG> is a virtual environment, indicated generally by the reference numeral <NUM>, in accordance with an example embodiment. The virtual environment <NUM> includes the user <NUM>, the first to third audio sources <NUM> to <NUM> and the first zone <NUM> described above. In the virtual environment <NUM>, the first zone <NUM> is positioned such that the user is at a central point of that zone. Thus, the virtual environment <NUM> shows the situation following the actuation of the operation <NUM> of the algorithm <NUM>.

In the virtual environment <NUM> in which the user experiences the constellation comprising the first to third audio sources <NUM> to <NUM> in the first audio mode, the audio sources are presented to the user <NUM> with six degrees-of-freedom. Thus, the user is able to move, whilst the positions of the audio sources remain fixed (so called "world locked"). The user can therefore experience the sound scene differently by moving relative to the audio sources <NUM> to <NUM> (and any other audio source, not shown, that might form a part of the audio constellation).

The algorithm <NUM> starts at operation <NUM>, where an audio mode is determined.

<FIG> is a virtual environment, indicated generally by the reference numeral <NUM>, in accordance with an example embodiment. The virtual environment <NUM> includes the user <NUM>, the first to third audio sources <NUM> to <NUM> and the first zone <NUM> described above. In the virtual environment <NUM>, the user <NUM> approaches or touches an edge or a boundary of the first zone <NUM> of the constellation. In response, it is determined in the operation <NUM> of the algorithm <NUM> that a second audio mode should be entered.

At operation <NUM> of the algorithm <NUM>, the second audio mode is initiated. In the second audio mode, the location of the audio sources <NUM> to <NUM> of the first audio and the first zone <NUM> move as the user moves. Thus, rather than moving outside the first zone <NUM>, the first audio constellation moves such that the user stays within the first zone. Thus, in contrast with the 6DoF audio presentation of the first audio mode, the second audio mode presents the audio constellation to the user <NUM> as 3DoF audio.

At operation <NUM> of the algorithm <NUM>, the rendering of audio to the user <NUM> is adjusted as the user moves.

<FIG> is a virtual environment, indicated generally by the reference numeral <NUM>, in accordance with an example embodiment. The virtual environment <NUM> includes the user <NUM>, the first to third audio sources <NUM> to <NUM> and the first zone <NUM>.

As shown in <FIG>, the first zone <NUM> moves from an initial position to a position <NUM> as the user <NUM> moves, such that the user remains in the centre of the first zone. The position of the audio constellation (comprising the first to the third audio sources <NUM> to <NUM>) and the first zone move gradually such that the user is eventually in the centre of the constellation and/or optimal listening position. The change may gradual such that the objects slowly slide towards the new locations, thereby smoothing the movement of the audio. A third party application, such as an immersive phone call may trigger this functionality to better allow user movement. In an immersive call scenario, it may be beneficial if the call audio scene will follow the user. As another example, starting an application such as sports tracker can trigger the functionality.

<FIG> is a flow chart showing an example algorithm, indicated generally by the reference numeral <NUM>, in accordance with an example embodiment. The algorithm <NUM> includes many of the features of the algorithms <NUM> and <NUM> described above.

The algorithm <NUM> starts at operation <NUM>, where the first audio mode is initiated (as in the operation <NUM> described above). As discussed above, in the first audio mode, first audio comprising a plurality of audio tracks located at different locations within a virtual scene is rendered to the user. The locations of the audio tracks within the virtual scene are fixed. Thus, the first audio is provided within a VR world about which the user can move (with <NUM>-DoF movement).

At operation <NUM> of the algorithm <NUM>, the user is placed at the centre of the first zone (and the relevant audio constellation), as in the operation <NUM> described above.

At operation <NUM>, a determination is made regarding whether the user is at (or approaching) the edge of the first zone <NUM>, as shown, for example, in <FIG> described above. If not, the algorithm remains in the first audio mode (and the user <NUM> is able to move relative to the audio tracks of the relevant audio constellation. If the user is at (or approaching) the edge of the first zone <NUM>, then the algorithm <NUM> moves to operation <NUM>.

At operation <NUM>, it is determined whether the user is exiting the constellation of audio tracks of the first audio (as discussed further below). If so, the algorithm <NUM> moves to operation <NUM>, where the algorithm is exited, resulting in ceasing to render the first audio to the user. If not, the algorithm <NUM> moves to operation <NUM> (discussed below). In one example embodiment, when an audio output (such as a song) being presented to the user ends, then the user automatically exits the constellation. The user can then enter another constellation and start consuming the audio within that constellation.

At operation <NUM>, it has already been determined that the user is at or approaching the boundary of the first zone <NUM> and that the user is not exiting that zone. In response, the second audio mode is initiated. This behaviour may be triggered, for example, by an external application, such as an immersive call. The user <NUM> may be able to avoid this behaviour by an interaction, such as dodging around objects while exiting the first zone. (This is one mechanism by which the user may be able to exit the first zone in the operation <NUM> referred to above.

At operation <NUM> of the algorithm <NUM>, a determination is made regarding whether the user <NUM> is stationary or moving. A determination is made regarding whether the user has been stationary for more than a threshold period of time. If the user <NUM> is determined to be stationary, then the algorithm moves to operation <NUM> (where the first audio mode is re-entered). Otherwise, the algorithm <NUM> remains in the second audio mode. Note that the threshold period of time could be variable (e.g. context specific).

In operation <NUM> of the algorithm <NUM>, the algorithm <NUM> is in the second mode of operation. In the second mode, the constellation of audio tracks <NUM> to <NUM> are user centric such that the user can drag the content in 3DoF. The rendering of the audio tracks is adjusted. For example, the rendering may be adjusted gradually such that movements are smoothed. In this way, the audio constellation can be gradually updated so that the user is finally in the centre of the constellation and/or optimal listening position. With the user in the middle of the relevant audio constellation, the constellation automatically moves together with the user (i.e. the audio is user-centric). As noted above, such constellations are particularly suitable for presenting legacy content such as music tracks which are available as multitrack recordings. The method conveniently enables user to listen to background music as the constellations of objects are automatically carried along with him, ensuring a nice listening experience even during movement.

The operation <NUM> of the algorithm <NUM> is repeated (and the algorithm remains in the second audio mode) until the user is deemed to be stationary in an instance of the operation <NUM>.

<FIG> is a virtual environment, indicated generally by the reference numeral <NUM>, in accordance with an example embodiment. The virtual environment <NUM> includes the user <NUM>, the first to third audio sources <NUM> to <NUM> and the first zone <NUM> described above. In the virtual environment <NUM>, the user <NUM> has exited the first zone <NUM> (thereby implementing the operation <NUM> of the algorithm <NUM>).

The user <NUM> may exit the first zone <NUM> by means of a defined interaction, such as dodging around objects while exiting the first zone <NUM>. The change of functionality can be visualized to the user, e.g., with different colouring of objects once the user <NUM> is outside the first zone <NUM>. Alternatively, or in addition, the user may exit the first zone <NUM> as a result of external factors, such as the ending of a media item providing the relevant audio content.

<FIG> is a block diagram of a system, indicated generally by the reference numeral <NUM>, in accordance with an example embodiment.

The system <NUM> is an example deployment of a 6DoF renderer for MPEG-I 6DoF audio. The skilled person will be aware of alternative possible implementations of the principles described herein.

The MPEG-I 6DoF audio renderer <NUM> receives an encoder input format specification or other specification, which describes the scene graph (e.g. scene geometry and object positions). Such input scene can also define the metadata for the content constellations.

Definitions used by the system <NUM> include at least some of:.

The triggering may be handled in the render side (such as the blocks "Interaction handling" and "Position & pose update" in the system <NUM>).

In world locked mode (first audio mode), the positions of audio objects with respect to the user are updated taking into account user translation in Euclidean coordinates x, y, z and rotation in yaw, pitch, roll. In user locked mode (second audio mode), the object positions with respect to the user are updated only considering the user head rotation in yaw, pitch and roll.

After object positions are updated, audio may rendered from the correct direction and distance using head-related-transfer-function (HRFT) filtering and distance/gain attenuation. Virtual acoustics such as reverberation adjusted to the characteristics of the virtual space can be used for enhancing the immersion. The skilled person will be aware of alternative implementation of such functions.

A number of extensions or modifications to the MPEG-I encoder input format (EIF) may be implemented in order to support aspects of example embodiments described herein. These may include:.

As example modification to the encoder input format (EIF), the following modifications can be done to implement the content zones functionality for MPEG-I 6DoF audio content.

Modifying the ObjectSource as shown below:.

The different types of firstRenderingMode can be the following:.

For completeness, <FIG> is a schematic diagram of components of one or more of the example embodiments described previously, which hereafter are referred to generically as a processing system <NUM>. The processing system <NUM> may, for example, be the apparatus referred to in the claims below.

The processing system <NUM> may have a processor <NUM>, a memory <NUM> closely coupled to the processor and comprised of a RAM <NUM> and a ROM <NUM>, and, optionally, a user input <NUM> and a display <NUM>. The processing system <NUM> may comprise one or more network/apparatus interfaces <NUM> for connection to a network/apparatus, e.g. a modem which may be wired or wireless. The network/apparatus interface <NUM> may also operate as a connection to other apparatus such as device/apparatus which is not network side apparatus. Thus, direct connection between devices/apparatus without network participation is possible.

The memory <NUM> may comprise a non-volatile memory, such as a hard disk drive (HDD) or a solid state drive (SSD). The ROM <NUM> of the memory <NUM> stores, amongst other things, an operating system <NUM> and may store software applications <NUM>. The RAM <NUM> of the memory <NUM> is used by the processor <NUM> for the temporary storage of data. The operating system <NUM> may contain code which, when executed by the processor implements aspects of the algorithms <NUM>, <NUM>, <NUM> and <NUM> described above. Note that in the case of small device/apparatus the memory can be most suitable for small size usage i.e. not always a hard disk drive (HDD) or a solid state drive (SSD) is used.

The processor <NUM> may take any suitable form. For instance, it may be a microcontroller, a plurality of microcontrollers, a processor, or a plurality of processors.

The processing system <NUM> may be a standalone computer, a server, a console, or a network thereof. The processing system <NUM> and needed structural parts may be all inside device/apparatus such as IoT device/apparatus i.e. embedded to very small size.

In some example embodiments, the processing system <NUM> may also be associated with external software applications. These may be applications stored on a remote server device/apparatus and may run partly or exclusively on the remote server device/apparatus. These applications may be termed cloud-hosted applications. The processing system <NUM> may be in communication with the remote server device/apparatus in order to utilize the software application stored there.

<FIG> show tangible media, respectively a removable memory unit <NUM> and a compact disc (CD) <NUM>, storing computer-readable code which when run by a computer may perform methods according to example embodiments described above. The removable memory unit <NUM> may be a memory stick, e.g. a USB memory stick, having internal memory <NUM> storing the computer-readable code. The internal memory <NUM> may be accessed by a computer system via a connector <NUM>. The CD <NUM> may be a CD-ROM or a DVD or similar. Other forms of tangible storage media may be used. Tangible media can be any device/apparatus capable of storing data/information which data/information can be exchanged between devices/apparatus/network.

Reference to, where relevant, "computer-readable medium", "computer program product", "tangibly embodied computer program" etc., or a "processor" or "processing circuitry" etc. should be understood to encompass not only computers having differing architectures such as single/multi-processor architectures and sequencers/parallel architectures, but also specialised circuits such as field programmable gate arrays FPGA, application specify circuits ASIC, signal processing devices/apparatus and other devices/apparatus. References to computer program, instructions, code etc. should be understood to express software for a programmable processor firmware such as the programmable content of a hardware device/apparatus as instructions for a processor or configured or configuration settings for a fixed function device/apparatus, gate array, programmable logic device/apparatus, etc..

Similarly, it will also be appreciated that the flow diagrams and message sequences of <FIG>, <FIG>, <FIG> and <FIG> are examples only and that various operations depicted therein may be omitted, reordered and/or combined.

It will be appreciated that the above described example embodiments are purely illustrative and are not limiting on the scope of the invention. Other variations and modifications will be apparent to persons skilled in the art upon reading the present specification.

Claim 1:
An apparatus comprising means configured to perform:
determining one of a plurality of audio modes for presentation of first audio to a user based on the location and/or movement of the user within a virtual scene, wherein the first audio comprises a plurality of audio tracks located at different locations within the virtual scene; and
rendering the first audio to the user in the determined audio mode, wherein: in a first audio mode of the plurality of audio modes, the locations of the audio tracks within the virtual scene are fixed and in a second audio mode of the plurality of audio modes, the locations of the audio tracks within the virtual scene move with the user,
wherein a transitioning from the second audio mode to the first audio mode is characterized in that the first audio mode is initiated immediately in the event that the user is determined to be stationary for more than a threshold period of time, otherwise the rendering is adjusted gradually such that the movements of the audio tracks are smoothed.