Abstract: Provided is a method of processing mesh data for processing an audio signal for audio rendering in a virtual reality (VR) space. The method includes receiving mesh data defining geometry of a certain space and the mesh data includes data regarding three-dimensional (3D) coordinates of points for configuring spatial information of the certain space and processing the mesh data by identifying outermost points among the points.

Abstract: Disclosed is an apparatus for immersive spatial audio modeling and rendering for effectively transmitting and playing immersive spatial audio content. The apparatus for immersive spatial audio modeling and rendering disclosed herein may model a spatial audio scene, generate and transmit parameters necessary for spatial audio rendering, and generate various spatial audio effects using the spatial audio parameters, to provide an immersive three-dimensional (3D) audio source coinciding with visual experience in a virtual reality space in response to free changes in the position and direction of a remote user in the space.

Abstract: Provided is a method of reproducing an ambisonic signal in a virtual reality (VR) space. The ambisonic signal reproduction method may include receiving an ambisonic signal, mapping the ambisonic signal to channels localized on a sphere according to an equivalent spatial domain (ESD) standard corresponding to an order of the ambisonic signal, and performing a sound field reproduction in the VR space based on the channels localized on the sphere.

Abstract: A method and apparatus for rendering an object-based audio signal considering an obstacle are disclosed. A method for rendering an object-based audio signal according to an example embodiment, the method includes identifying an object-based input signal and metadata for the input signal, generating a binaural filter based on the metadata using a binaural room impulse response (BRIR), determining, based on the metadata, whether an obstacle is present between a listener and an object, modifying the generated binaural filter when it is determined that the obstacle is present, and generating a rendered output signal by convolving the modified binaural filter and the input signal.

Abstract: Provided is a method and apparatus for generating an impulse response using ray tracing. The method of generating an impulse response may include calculating a number of rays reaching a receiver from a transmitter based on acoustic geometry information including a position of the transmitter and a position of the receiver disposed in a sound space, a maximum ray length or a sound space volume, and a radius of the receiver, tracing the rays using a path of the calculated rays, and generating an impulse response based on the traced rays.

Abstract: A method and apparatus for processing acoustic spatial information are provided. The method of processing acoustic spatial information includes identifying at least one mesh disposed in an acoustic space, setting a minimum cuboid surrounding the mesh as a bounding box, and generating acoustic spatial information including information about the bounding box.

Abstract: Disclosed is a binaural rendering method and apparatus for decoding a multichannel audio signal. The binaural rendering method may include: extracting an early reflection component and a late reverberation component from a binaural filter; generating a stereo audio signal by performing binaural rendering of a multichannel audio signal base on the early reflection component; and applying the late reverberation component to the generated stereo audio signal.

Abstract: Provided is an acoustic signal processing device for a spatially extended sound source and a method thereof. The acoustic signal processing device includes a memory configured to store instructions, and a processor electrically connected to the memory and configured to execute the instructions. When the instructions are executed by the processor, the processor performs a plurality of operations, and the plurality of operations includes transforming an object provided as a spatially extended sound source into a cuboid in a virtual reality (VR) space, obtaining coordinates of the cuboid, and determining a position of a sound source of the object based on the coordinates of the cuboid and coordinates of a user in the VR space.

Abstract: An apparatus and method for pitch-shifting an audio signal with low complexity are disclosed. The method includes identifying a distance between an audio object included in the audio signal and a listener, checking whether the distance between the audio object and the listener decreases, and performing stepwise stretching pitch-shifting of repeatedly using at least one of frequency components of the audio signal when the distance between the audio object and the listener decreases.

Abstract: A method and apparatus for performing binaural rendering of an audio signal are provided. The method includes identifying an input signal that is based on an object, and metadata that includes distance information indicating a distance to the object, generating a binaural filter that is based on the metadata, using a binaural room impulse response, obtaining a binaural filter to which a low-pass filter (LPF) is applied, using a frequency response control that is based on the distance information, and generating a binaural-rendered output signal by performing a convolution of the input signal and the binaural filter to which the LPF is applied.

Abstract: A Unified Speech and Audio Codec (USAC) that may process a window sequence based on mode switching is provided. The USAC may perform encoding or decoding by overlapping between frames based on a folding point when mode switching occurs. The USAC may process different window sequences for each situation to perform encoding or decoding, and thereby may improve a coding efficiency.

Abstract: Disclosed is an LPC residual signal encoding/decoding apparatus of an MDCT based unified voice and audio encoding device. The LPC residual signal encoding apparatus analyzes a property of an input signal, selects an encoding method of an LPC filtered signal, and encode the LPC residual signal based on one of a real filterbank, a complex filterbank, and an algebraic code excited linear prediction (ACELP).

Abstract: A method and apparatus for rendering a volume sound source are disclosed. The method of rendering a volume sound source may include identifying information about a listener and information about the volume sound source, determining a corresponding area in which a source element is disposed in the volume sound source in consideration of the information about the listener, determining an angle between the listener and the corresponding area based on the information about the listener and the information about the volume sound source, determining a number of source elements disposed in the corresponding area according to the angle, determining a position and a gain of the source element using i) the number of source elements and ii) a distance between the listener and the volume sound source, and rendering the volume sound source according to the position and the gain of the source element.

Abstract: A method and system for processing an obstacle effect in a virtual acoustic space are disclosed. The method includes receiving a parameter for an obstacle candidate plane extracted from spatial information, determining, in response to the parameter, whether the obstacle candidate plane is an obstacle related to a path between a position of a virtual sound source and a position of a user, and applying a sound effect according to the obstacle to an audio signal when the obstacle candidate plane is the obstacle. The obstacle candidate plane is a plane of an object that may become the obstacle in a sound propagation path between the virtual sound source and the user.

Abstract: Provided are an apparatus and a method for integrally encoding and decoding a speech signal and a audio signal. The encoding apparatus may include: an input signal analyzer to analyze a characteristic of an input signal; a first conversion encoder to convert the input signal to a frequency domain signal, and to encode the input signal when the input signal is a audio characteristic signal; a Linear Predictive Coding (LPC) encoder to perform LPC encoding of the input signal when the input signal is a speech characteristic signal; and a bitstream generator to generate a bitstream using an output.

Abstract: Disclosed is an LPC residual signal encoding/decoding apparatus of an MDCT based unified voice and audio encoding device. The LPC residual signal encoding apparatus analyzes a property of an input signal, selects an encoding method of an LPC filtered signal, and encode the LPC residual signal based on one of a real filterbank, a complex filterbank, and an algebraic code excited linear prediction (ACELP).

Abstract: A Unified Speech and Audio Codec (USAC) that may process a window sequence based on mode switching is provided. The USAC may perform encoding or decoding by overlapping between frames based on a folding point when mode switching occurs. The USAC may process different window sequences for each situation to perform encoding or decoding, and thereby may improve a coding efficiency.

Abstract: An encoding/decoding apparatus and method for controlling a channel signal is disclosed, wherein the encoding apparatus may include an encoder to encode an object signal, a channel signal, and rendering information for the channel signal, and a bit stream generator to generate, as a bit stream, the encoded object signal, the encoded channel signal, and the encoded rendering information for the channel signal.

Abstract: A method of applying a Doppler effect to an object audio signal and a rendering apparatus performing the method are disclosed. The method includes determining a relative velocity between an audio object and an observer based on a velocity and a direction of the audio object and a position of the observer, determining whether to apply the Doppler effect based on the relative velocity, applying the Doppler effect based on the relative velocity to the object audio signal in response to a determination to apply the Doppler effect, and rendering an object audio signal to which the Doppler effect is applied.

Abstract: Disclosed is a method and apparatus for processing an audio signal based on an extent sound source. The method includes identifying information on a reference area of the extent sound source and information on a position of a listener, determining a position of a virtual sound source within the extent sound source based on a relationship between the position of the listener and the reference area of the extent sound source, and rendering an audio signal based on the determined position of the virtual sound source, wherein the reference area may be determined based on a position and a size of the extent sound source.