Patent application number | Description | Published |
20080228500 | METHOD AND APPARATUS FOR ENCODING/DECODING AUDIO SIGNAL CONTAINING NOISE AT LOW BIT RATE - A method and apparatus for encoding/decoding audio signals at a low bit rate are provided. The encoding apparatus selectively encodes one or more reference samples having the highest amplitudes among frequency samples of an audio signal, determines amplitudes of the remaining samples other than the reference sample according to a predetermined pattern, using a predetermined random function, and then encodes the remaining samples using random function input information for causing the same pattern to be generated using the same random function, thus maximizing an encoding rate for an audio signal having a large amount of noise. | 09-18-2008 |
20080235033 | METHOD AND APPARATUS FOR ENCODING AUDIO SIGNAL, AND METHOD AND APPARATUS FOR DECODING AUDIO SIGNAL - 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. | 09-25-2008 |
20080235034 | METHOD AND APPARATUS FOR ENCODING AUDIO SIGNAL AND METHOD AND APPARATUS FOR DECODING AUDIO SIGNAL - Provided are a method and apparatus for encoding an audio signal to efficiently encode a harmonic envelope and a method and apparatus for decoding an audio signal to decode the harmonic envelope. The method of encoding an audio signal includes performing harmonic analysis with respect to an input signal to determine harmonic parameters with respect to harmonic signals; regarding amplitudes of the harmonic signals included in the harmonic parameters as signals in the time domain so as to perform time-frequency transformation; and encoding the time-frequency transformed values. When expressing a harmonic envelope, the amplitudes of the harmonic signals are regarded as signals in the time domain so as to perform a time-frequency transformation and only a part from among the transformed values is selected to be encoded. Therefore, sound quality is not affected and coding efficiency greatly improves. | 09-25-2008 |
20080255855 | Method and apparatus for coding and decoding amplitude of partial - Provided are a method and apparatus for coding and decoding an amplitude of partials, in which a step phenomenon can be prevented in the result of coding the amplitude of continuation partial partials in a parametric codec, thereby improving reproduced sound quality. The method of coding the amplitude of partials includes obtaining an inversely quantized amplitude of partials of a previous frame, determining a quantization level based on a function for the inversely quantized amplitude of the partials of the previous frame, and quantizing an amplitude of partials of a current frame based on the determined quantization level. | 10-16-2008 |
20080294445 | METHOD AND APAPRATUS FOR SINUSOIDAL AUDIO CODING - Provided are a method and apparatus for sinusoidal audio coding, which employs a tracking method for further effective coding of sinusoids extracted in the process of a sinusoidal analysis of parametric coding. The sinusoidal audio coding method includes: extracting sinusoids of a current frame by performing a sinusoidal analysis on an input audio signal; with respect to each of the extracted sinusoids, setting a mode selected from a birth mode in which a sinusoid is newly generated irrespective of sinusoids of a previous frame, a continuation mode in which the sinusoid is only one sinusoid continued from one of the sinusoids of the previous frame, and a branch mode in which the sinusoid is one of a plurality of sinusoids continued from one of the sinusoids of the previous frame; and coding the extracted sinusoids according to the selected mode. Accordingly, a plurality of sinusoids that can be continued from one previous track component are set to the continuation mode or the branch mode. Therefore, the number of bits of coded data is significantly reduced, compared with the case of the birth mode. | 11-27-2008 |
20090024396 | AUDIO SIGNAL ENCODING METHOD AND APPARATUS - An audio signal encoding method and apparatus for efficiently encoding an audio signal in an interval having many birth sinusoids and enabling tracking of sinusoidal signals in the next interval, and a computer readable recording medium having embodied thereon a computer program for executing the audio signal encoding method are provided. According to the method and apparatus, by applying transform coding instead of parametric coding to a frame having many birth sinusoids, the sinusoids are encoded, thereby reducing the number of bits required for the encoding and enabling efficient coding. Also, when transform coding is applied to a frame of a predetermined interval, an inverse transform of the transform coding is applied to the encoded data in order to decode the data, and then sinusoids are extracted from the decoded data, thereby enabling tracking of sinusoids of the next frame. | 01-22-2009 |
20090048826 | ENCODING METHOD AND APPARATUS FOR EFFICIENTLY ENCODING SINUSOIDAL SIGNAL WHOSE MAGNITUDE IS LESS THAN MASKING VALUE ACCORDING TO PSYCHOACOUSTIC MODEL AND DECODING METHOD AND APPARATUS FOR DECODING ENCODED SINUSOIDAL SIGNAL - 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). | 02-19-2009 |
20090060024 | METHOD AND APPARATUS FOR ENCODING/DECODING MEDIA SIGNAL - 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 (M03-05-2009 | |
20090192789 | METHOD AND APPARATUS FOR ENCODING/DECODING AUDIO SIGNALS - 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. | 07-30-2009 |
20090192792 | METHODS AND APPARATUSES FOR ENCODING AND DECODING AUDIO SIGNAL - 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. | 07-30-2009 |
20090198489 | METHOD AND APPARATUS FOR FREQUENCY ENCODING, AND METHOD AND APPARATUS FOR FREQUENCY DECODING - 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. | 08-06-2009 |
20090198499 | METHOD AND APPARATUS FOR ENCODING RESIDUAL SIGNALS AND METHOD AND APPARATUS FOR DECODING RESIDUAL SIGNALS - 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. | 08-06-2009 |
20090198501 | METHOD AND APPARATUS FOR ENCODING/DECODING AUDIO SIGNAL USING ADAPTIVE LPC COEFFICIENT INTERPOLATION - 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. | 08-06-2009 |
20090210236 | METHOD AND APPARATUS FOR ENCODING/DECODING STEREO AUDIO - 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. | 08-20-2009 |