A low-quality rendition of a complex soundtrack is created, synchronized and combined with the soundtrack. The low-quality rendition may be monitored in mastering operations, for example, to control the removal, replacement or addition of aural content in the soundtrack without the need for expensive equipment that would otherwise be required to render the soundtrack.

A method for processing audio signals for creating a three dimensional sound environment includes: receiving at least one input signal from at least one sound source; creating a simulated signal at least partly based on the received at least one input signal, the simulated signal representing a simulation of at least one input signal reflecting from the ground or a floor; and creating an output signal at least partly on the basis of the simulated signal and the at least one received input signal, the output signal including a plurality of audio channels; at least two channels of the audio channels of the output signal representing signals for sound transducers above a listener's ear level at a nominal listening position, and at least two channels of the audio channels of the output signal representing signals for sound transducers below a listener's ear level at a nominal listening position.

An audio playback device which plays back an audio object including an audio signal and playback position information indicating a position in a three-dimensional space at which a sound image of the audio signal is localized, includes: at least one speaker array; a converting unit which converts playback position information to corrected playback position information which is information indicating a position of the sound image on a two-dimensional coordinate system based on a position of the at least one speaker array; and a signal processing unit which localizes the sound image of the audio signal included in the audio object according to the corrected playback position information.

In an encoding section (100), a downmix section (110) forms first and second channels (L.sub.1, L.sub.2) of a downmix signal as linear combinations of first and second groups (401, 402) of channels, respectively, of an M-channel audio signal; and an analysis section (120) determines upmix parameters (α.sub.LU) for parametric reconstruction of the audio signal, and mixing parameters (α.sub.LM). In a decoding section (1200), a decorrelating section (1210) outputs a decorrelated signal (D) based on the downmix signal; and a mixing section (1220) determines mixing coefficients based on the mixing parameters or the upmix parameters, and forms a K-channel output signal ({tilde over (L)}.sub.1, . . . , {tilde over (L)}.sub.K) as a linear combination of the downmix signal and the decorrelated signal in accordance with the mixing coefficients. The channels of the output signal approximate linear combinations of K groups (501-502, 1301-1303) of channels, respectively, of the audio signal. The K groups constitute a different partition of the audio signal than the first and second groups, and 2≦K<M.

During a process, decorrelation may be selectively applied to audio data for an audio object based, at least in part, on whether a speaker for which speaker feed signals will be determined is a surround speaker. In some implementations, decorrelation may be selectively applied according to whether such a speaker is a height speaker. Some implementations may reduce, or even eliminate, audio artifacts such as comb-filter notches and peaks. Some such implementations may increase the size of a “sweet spot” of a reproduction environment.

To enable multichannel audio data to be transmitted favorably. Multichannel audio data of a predetermined number of channels is acquired. The multichannel audio data has a sampling frequency corresponding to the predetermined number of channels. Audio data of the respective channels configuring the multichannel audio data are sequentially transmitted to a reception side via a predetermined transmission channel for each unit audio data. Information indicating the sampling frequency is added to the transmission audio data.

A new service can be provided as maintaining the compatibility with a related audio receiver, without deteriorating an efficient usage of a transmission band. A predetermined number of audio streams having first encoded data and second encoded data which is related to the first encoded data are generated, and a container in a predetermined format including these audio streams is transmitted. The predetermined number of audio streams are generated so that the second encoded data is discarded in a receiver which is not compatible with the second encoded data.

Provided is a method of controlling an audio output according to an orientation of an audio output apparatus, performed by the audio output apparatus, the method including receiving a stereo signal; detecting the orientation of the audio output apparatus using a sensor; outputting the stereo signal to a left speaker unit and a right speaker unit from a viewpoint of a user who views a front surface portion of the audio output apparatus on which two speaker units are arranged; and down-mixing the stereo signal and outputting the down mixed signal to at least one among an upper speaker unit and a lower speaker unit from the user's viewpoint.

The present technology relates to an encoding device and method, a decoding device and method, and a program which can obtain high quality audio with a less code amount. A signal encoding unit encodes audio signals and outputs a resultant signal code string. A coefficient encoding unit encodes mixing coefficients for use in a mixing process of the audio signals and outputs a resultant coefficient code string. A multiplexing unit multiplexes the signal code string and the coefficient code string and outputs a resultant output code string. The coefficient encoding unit rearranges the mixing coefficients at the time of encoding the mixing coefficients on the basis of distances between input-side sound source positions and speaker positions on a reproduction side and calculates differential values between the mixing coefficients on the basis of arrangement order of the mixing coefficients, thereby encoding the mixing coefficients. The present technology is applicable to the encoding device and the decoding device.

An audio processor may receive audio input channels including stereo channels and one or more surround channels. The audio processor may downmix the audio input channels into stereo output channels; developing the stereo output channels into upmixed audio channels including at least one additional surround channel not present in the audio input channels; delay the audio input channels into delayed audio channels that are time-aligned with the upmixed audio channels; and mix the delayed audio channels and the upmixed audio channels into audio output channels.