Abstract: Methods and apparatuses for encoding and decoding of an audio signal using a mixture of a time-frequency method and a parametric method according to the audio band are provided. An encoding method of an audio signal includes: dividing input audio signals into a plurality of audio bands; selecting a coding method for each audio band; encoding each audio band according to the selected coding method for each band; and generating a bit stream including all the data encoded for each audio band, wherein selecting a coding method for each band comprises selecting smaller encoded data either from a parametric coding method or a time frequency coding method.

Abstract: A method and apparatus for decoding a parametric-encoded audio signal are provided. According to the present invention, parameters extracted from a bitstream of a parametric encoded audio signal are adjusted by a user and component signals are synthesized based on the adjusted parameters to be displayed to a user so that a user can adjust the amplitudes of the component signals to apply various sound effects according to the user's desire. In addition, since an equalizer function is embodied in a codec of an audio reproduction apparatus, additional equalizer modules are not required and thus complexity of the audio reproduction apparatus can be reduced.

Abstract: Methods and apparatuses for encoding and decoding an audio signal are provided, a method of encoding an audio signal including: receiving the audio signal including information about a moving sound source; receiving position information about the moving sound source; generating dynamic track information indicating motion of the moving sound source by using the position information; and encoding the audio signal and the dynamic track information.

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 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 multi-channel audio signal encoding and decoding method and apparatus are provided. The multi-channel audio signal encoding method, the method including: obtaining semantic information for each channel; determining a degree of similarity between multi-channels based on the obtained semantic information for each channel; determining similar channels among the multi-channels based on the determined degree of similarity between the multi-channels; and determining spatial parameters between the similar channels and down-mixing audio signals of the similar channels.

Abstract: An audio signal encoding method and apparatus and an audio signal decoding method and apparatus are provided. The audio signal encoding method includes: transforming an audio signal into a signal of a frequency domain; extracting semantic information from the audio signal; variably reconfiguring one or more sub-bands included in the audio signal by segmenting or grouping the one or more sub-bands using the extracted semantic information; and generating a quantized bitstream by calculating a quantization step size and a scale factor with respect to a reconfigured sub-band of the one or more sub-bands.

Abstract: Provided are methods and apparatuses for displaying a stereoscopic image. The method includes alternately generating repeated left-eye images and repeated right-eye images; turning off a backlight unit during a period in which a left-eye image and a right-eye image are mixed and turning on the backlight unit during a period in which only one of the left-eye and right-eye images is displayed; and controlling a left-eye shutter and a right-eye shutter of shutter glasses during a period in which the backlight unit is turned on.

Abstract: A method and apparatus for encoding a multi-channel audio signal is provided. The method includes the operations of selecting a first variable length code table (VLC) that is to be used to encode the multi-channel audio signal in a given frequency band, from among a plurality of VLC tables, and encoding the multi-channel audio signal by using the first VLC table. Thus, the multi-channel audio signal can be encoded by using VLC tables that differ according to frequency bands.

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: 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: 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: Encoding and decoding of residual signals are provided. In a method of encoding a residual signal of an audio signal, the residual signal is divided into a plurality of sections having different sizes, based on a change of the residual signal. Then, section division information representing information about the divided sections and section-by-section residual signal information representing characteristics of the sections of the residual signal are acquired. Thereafter, the residual signal is encoded based on the section division information and the section-by-section residual signal information.

Abstract: Provided are methods and apparatuses for more efficiently encoding and decoding a high frequency band signal which is from an audio signal and which is greater than a predetermined threshold frequency. The method and apparatus for encoding the audio signal encodes a linear prediction coding (LPC) coefficient and gain information of a residual signal, which are generated by performing LPC analysis, thereby encoding a high frequency signal so as to have enhanced sound quality, while using less bits.

Abstract: Provided are a method and apparatus for effectively encoding/decoding remaining difference signals excluding sinusoidal components, from input audio signals. In the method and apparatus for encoding audio signals, sinusoidal analysis is performed on low frequency signals of less than a predetermined critical frequency in order to extract sinusoidal signals and then, an encoding operation is performed on the remaining difference signals excluding the sinusoidal signals, from input audio signals, by using linear prediction coding (LPC) analysis.

Abstract: Provided are parametric audio encoding and decoding apparatuses and methods thereof. In the parametric audio encoding method, an audio signal is segmented into a plurality of segments. At least one sine wave is extracted from each of the segments, and the extracted sine waves are connected. It is determined whether an extracted sine wave is a birth sine wave. If the extracted sine wave is a birth sine wave, a bit stream is generated by encoding the phase of the birth sine wave on the basis of the frequency of the birth sine wave, wherein the number of bits allocated to encode the phase of the birth sine wave is adjusted according to the frequency of the birth sine wave.

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 method and apparatus for encoding/decoding a media signal. The method of encoding a media signal includes: when harmonics exist in a sinusoid of a previous frame section, predicting a harmonic frequency of a current frame section that is to be encoded by using a harmonic frequency of the previous frame section, and generating a residual signal by using a difference between the predicted frequency and an actual harmonic frequency of the current frame section.

Abstract: Provided are an audio signal encoding method and apparatus that encode a continuation sinusoidal signal of a current frame in different ways according to information on a sinusoidal signal of a previous frame by using the characteristics of the continuation sinusoidal signal, and an audio signal decoding method and apparatus. The audio signal encoding method includes extracting a sinusoidal signal of a current frame by performing sinusoidal analysis on an input audio signal; extracting a continuation sinusoidal signal of the current frame, which is connected to a sinusoidal signal of a previous frame, by performing sinusoidal tracking of the extracted sinusoidal signal of the current frame; and encoding the continuation sinusoidal signal in different ways by using information on the sinusoidal signal of the previous frame, which is connected to the continuation sinusoidal signal.

Abstract: Provided are a method and apparatus for encoding an audio signal and a method and apparatus for decoding an audio signal. The method includes performing sinusoidal analysis on an audio signal in order to extract a sinusoidal signal of a current frame, determining continuation sinusoidal signal information indicating a number of continuation sinusoidal signals of next frames, which continue from the sinusoidal signal of the current frame, by performing sinusoidal tracking on the extracted sinusoidal signal of the current frame, and encoding the determined continuation sinusoidal signal information by using different Huffman tables according to index information of the current frame, thereby allowing efficient encoding with a low bitrate.