Abstract: A method and apparatus for generating synthesis audio signals are provided. The method includes decoding a bitstream; splitting the decoded bitstream into n sub-band signals; generating n transformed sub-band signals by transforming the n sub-band signals in a frequency domain; and generating synthesis audio signals by respectively multiplying the n transformed sub-band signals by values corresponding to synthesis filter bank coefficients.

Abstract: Exemplary embodiments may provide a method of encoding an audio signal. The method includes: segmenting the audio signal into a plurality of frames, wherein each of the frames includes M samples and M is a natural number greater than one; applying a first window, a second window, and at least one third window to the frames, wherein a length of the second window is longer than a length of the first window, and a length of the third window is longer than the length of the first window and shorter than the length of the second window; time-frequency transforming the frames to which the first window, the second window, and the at least one third window have been applied; and generating a bitstream including the time-frequency transformed frames.

Abstract: A method of encoding stereo audio that minimizes a number of pieces of side information required for parametric-encoding and parametric-decoding of the stereo audio. The side information may include parameters about interchannel intensity difference (IID), interchannel correlation (IC), overall phase difference (OPD), and interchannel phase difference (IPD), which are required to restore the mono audio to the stereo audio.

Abstract: Provided is a method of encoding an audio signal. A method of encoding an audio signal includes generating a modified signal of a time domain to compensate a frequency resolution in frame units, analysis-windowing the modified signal of the time domain by using a window type which is designed to have an overlapping section less than 50%, and generating transform coefficients of a frequency domain by transforming the analysis-windowed signal of the time domain.

Abstract: Provided are a method and apparatus for transmitting digital multimedia broadcasting data, and a method and apparatus for receiving digital multimedia broadcasting data. A basic audio signal and a multichannel audio signal are encoded to generate a basic audio stream and a multichannel audio stream, and a first data stream describing property and position data of the basic audio stream and a second data stream describing property and position data of the multichannel audio stream are transmitted as independent streams. According to the performance of the receiving apparatus, an audio signal may be decoded by using just the first data stream only or both the first data stream and the second stream.

Abstract: Provided are a method and apparatus for encoding/decoding stereo audio. In the method for encoding stereo audio, stereo audio is encoded based on at least one of the phase difference between first and second channel audios and information on an angle made by a vector on the intensity of mono-audio and a vector on the intensity of the first channel audio or a vector on the intensity of the second channel audio. Thus, the number of encoded parameters is minimized so that a compression ratio in the encoding of the stereo audio is improved.

Abstract: A method and apparatus to enhance one or more low-frequency components and one or more medium-frequency components of an audio signal. The method includes performing filtering on the input audio signal using a plurality of band-pass filters, generating a plurality of harmonic-frequency signals using a plurality of audio signals resulting from the performing filtering operation, and mixing the plurality of harmonic-frequency signals with the input audio signal.

Abstract: Provided are a method and apparatus for encoding/decoding stereo audio. In the method for encoding stereo audio, stereo audio is encoded based on at least one of the phase difference between first and second channel audios and information on an angle made by a vector on the intensity of mono-audio and a vector on the intensity of the first channel audio or a vector on the intensity of the second channel audio. Thus, the number of encoded parameters is minimized so that a compression ratio in the encoding of the stereo audio is improved.

Abstract: A residual signal decoding method including dividing a signal into a plurality of sub-bands in a frequency domain, wherein the signal is in a residual signal and is encoded with respect to an effective residual signal exceeding a masking curve that is generated with respect to a multi-channel audio signal, transforming the frequency domain into a time domain, and restoring the signal as an effective residual signal by synthesizing signals of the domain-transformed sub-bands.

Abstract: Provided are a method and apparatus for encoding or decoding an audio signal by adaptively interpolating a linear predictive coding (LPC) coefficient. In the method and apparatus of encoding or decoding an audio signal, LPC coefficient interpolation is selectively performed depending on whether a transient section is present in a current frame, thereby preventing noise from occurring when interpolating LPC coefficients in the transient section.

Abstract: Provided is a multi-channel audio decoding method and apparatus therefor, the method involving decoding filter bank coefficients of a plurality of bands from a bitstream having a predetermined format; performing frequency transformation on the decoded filter bank coefficients of the plurality of bands, with respect to each of the plurality of bands; compensating for a phase of each of the plurality of bands according to a predetermined phase compensation value, and serially band-synthesizing the frequency-transformed coefficients of each of the plurality of phase-compensated bands on a frequency domain; and decoding a multi-channel audio signal from the band-synthesized frequency-transformed coefficients.

Abstract: A method and apparatus for encoding/decoding a media signal. The method of decoding a media signal includes extracting first table index information from a header. The first table index information indicates M (M<N) tables substantially referred to by frames from among N tables which can be referred to for performing an operation performed by the frames, wherein N and M are natural numbers. Second table index information is then extracted from each frame. The second table index information indicates tables referred to by each frame from among M tables. The tables, which are referred to by the frames, are then identified by using the first and second table index information and the frames are decoded by referring to identified tables.

Abstract: Provided are a multi-channel audio down-mixing method and apparatus for selecting down-mix target channels based on a calculation of correlations between channels and then down-mixing the down-mix target channels. The method includes: calculating correlations between channels of multi-channel audio; selecting a first channel and a second channel, among the channels of the multi-channel audio, that are to be down-mixed, based on the calculated correlations; and down-mixing the selected first channel and the selected second channel.

Abstract: A signal processing method performed by an encoding apparatus that down-mixes first through n channel signals to a mono-signal, an encoding apparatus, a decoding apparatus, and a decoding method are provided. The signal processing method includes: generating a spatial parameter between a reference channel signal that is from among the first through n channel signals, and residual channel signals from among the first through n channel signals except for the reference channel signal; and encoding and transmitting the spatial parameter to a decoding apparatus, whereby a down-mixed mono-signal may be exactly restored to original channel input signals.

Abstract: Provided are a method and apparatus for encoding the frequency of a continuation sinusoidal signal and a method and apparatus for decoding the same. In the encoding method, a continuation sinusoidal signal successive to a sinusoidal signal in a previous section is extracted from a current section; a frequency of the continuation sinusoidal signal at the boundary between the current and previous sections is changed to a first frequency, based on representative frequencies of the continuation sinusoidal signal and at least one sinusoidal signal that belongs to a section adjacent to the current section and is successive to the continuation sinusoidal signal; and the first frequency is encoded.

Abstract: A binaural decoder for an MPEG surround stream, which decodes an MPEG surround stream into a stereo 3D signal, and a decoding method thereof. The method includes dividing a compressed audio stream and head related transfer function (HRTF) data into subbands, selecting predetermined subbands of the HRTF data divided into subbands and filtering the HRTF data to obtain the selected subbands, decoding the audio stream divided into subbands into a stream of multi-channel audio data with respect to subbands according to spatial additional information, and binaural-synthesizing the HRTF data of the selected subbands with the multi-channel audio data of corresponding subbands.

Abstract: A binaural decoder for an MPEG surround stream, which decodes an MPEG surround stream into a stereo 3D signal, and a decoding method thereof. The method includes dividing a compressed audio stream and head related transfer function (HRTF) data into subbands, selecting predetermined subbands of the HRTF data divided into subbands and filtering the HRTF data to obtain the selected subbands, decoding the audio stream divided into subbands into a stream of multi-channel audio data with respect to subbands according to spatial additional information, and binaural-synthesizing the HRTF data of the selected subbands with the multi-channel audio data of corresponding subbands.

Abstract: Provided are an encoding method and apparatus for efficiently encoding a sinusoidal signal whose magnitude is less than a masking value according to a psychoacoustic model, a decoding method and apparatus for decoding an encoded sinusoidal signal, and a computer-readable recording medium having recorded thereon a program for executing the encoding method/the decoding method. By using a particular code indicating that the magnitude of a first sinusoidal signal is less than a masking value according to a psychoacoustic model to encode the first sinusoidal signal, difference coding for a third sinusoidal signal of a next frame, which is connected to the first sinusoidal signal, is performed using a sinusoidal signal or sinusoidal signals selected according to a method to use the particular code, and a decoding apparatus obtains a sum with a transmitted difference using the selected sinusoidal signal(s).

Abstract: An audio signal processing method includes: receiving an audio signal comprising consecutive frames; generating a first encoding parameter corresponding to a first frame among the consecutive frames and a second encoding parameter corresponding to a second frame adjacent to the first frame; and generating at least one interpolated parameter based on the first encoding parameter and the second encoding parameter.

Abstract: A method processing a signal, an encoding apparatus, and a decoding apparatus are provided. The method of processing a signal includes restoring a down-mixed original signal using a re-quantized prediction parameter to generate a restored signal in an encoding apparatus; generating mute information indicating whether the down-mixed original signal has been muted, according to a value of the restored signal; and transmitting the mute information and the down-mixed original signal from the encoding apparatus to a decoding apparatus.