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Iwagami Naoki, Moriya Takehiro, Jin Akio, Chikira Kazuaki, Mori Takeshi: Audio signal encoding method and decoding method, device therefor, and program recording medium. Nippon Telegr &Amp Teleph Corp &Lt Ntt&Gt, December 8, 2000: JP2000-338998 (17 worldwide citation)

PROBLEM TO BE SOLVED: To encode an input voice containing a tone component much in high area with high efficiency by dividing the frequency area coefficient of an input signal sample to generate a coefficient small piece group, classifying the coefficient small pieces to a plurality of groups follow ...


2
Moriya Takehiro, Iwagami Naoki, Jin Akio, Mori Takeshi: Coding method of stereophonic signal. Nippon Telegr &Amp Teleph Corp &Lt Ntt&Gt, September 21, 2001: JP2001-255892 (11 worldwide citation)

PROBLEM TO BE SOLVED: To reduce the degradation in quality even though the amount of information is small while left and right signals are extremely similar with respect to each other.SOLUTION: Sum and difference vectors M and S of left and right signals L and S are obtained (12). These vectors are ...


3
Moriya Takehiro, Iwagami Naoki, Jin Akio, Mori Takeshi, Chikira Kazuaki: Reversible coding method, reversible decoding method, system adopting the methods and each program recording medium. Nippon Telegr &Amp Teleph Corp &Lt Ntt&Gt, February 16, 2001: JP2001-044847 (10 worldwide citation)

PROBLEM TO BE SOLVED: To compress a digital input signal at a high compression rate and to completely reproduce the signal. SOLUTION: This reversible coding method includes a process, where a digital input signal is converted into a bit stream in a code absolute value expression for each frame, a pr ...


4
Moriya Takehiro, Iwagami Naoki, Mori Takeshi, Jin Akio: Method for hierarchically encoding and decoding acoustic signal. Nippon Telegr &Amp Teleph Corp &Lt Ntt&Gt, August 24, 2001: JP2001-230675 (6 worldwide citation)

PROBLEM TO BE SOLVED: To reduce the effects of a transmission error or packet loss by deforming an error spread over hierarchies, in bit rate scalable encoding and decoding, based on hierarchical quantization such as controlling of an amplitude.SOLUTION: A signal, deformed into input signal by a fir ...


5
Jin Akio, Moriya Takehiro, Iwagami Naoki, Mori Takeshi, Chikira Kazuaki: Method and device for encoding signal, recording medium recorded with signal encoding program. Nippon Telegr &Amp Teleph Corp &Lt Ntt&Gt, April 26, 2002: JP2002-123298 (5 worldwide citation)

PROBLEM TO BE SOLVED: To provide a method for masking hearing sensation highly accurately by precisely estimating the position of a mountain and a valley in a spectral envelope curved line when vocal and musical sound signals are encoded.SOLUTION: The device is provided with a T/F converter 11 which ...


6
Iwagami Naoki, Mori Takeshi: Audio signal encoding method and decoding methods, and storage medium stored with program to execute these methods. Nippon Telegr &Amp Teleph Corp &Lt Ntt&Gt, March 27, 2002: JP2002-091497 (3 worldwide citation)

PROBLEM TO BE SOLVED: To efficiently encode and decode audio signals having a complex- shaped spectrum.SOLUTION: It is selected that frequency region coefficients are encoded for every small band by using any method from plural encoding methods. The coefficients are encoded by a selected encoding me ...


7
Iwagami Naoki, Chikira Kazuaki: Method for encoding audio signal, decoding method, and program storage medium for executing the methods. Nippon Telegr &Amp Teleph Corp &Lt Ntt&Gt, March 12, 2002: JP2002-073093 (2 worldwide citation)

PROBLEM TO BE SOLVED: To provide a method for supporting the grasp of the outline of an audio signal when presenting an encoded audio signal and, particularly, presenting it through a transmission channel by efficiently performing operations such as quick listening, skipping listening.SOLUTION: Whil ...


8
Chikira Kazuaki, Iwagami Naoki: Musical sound coding method, musical sound decoding method and recording medium recorded with program to execute these methods. Nippon Telegr &Amp Teleph Corp &Lt Ntt&Gt, November 16, 2001: JP2001-318684 (2 worldwide citation)

PROBLEM TO BE SOLVED: To realize a coding and decoding method that eliminates the waste and easily edits and processes for the system in which acoustic information being transmitted is received, temporarily recorded in a recording medium, reproduced, edited, processed and speed varied resulting in a ...


9
Iwagami Naoki, Moriya Takehiro: Conjugate structure vector quantization method. Nippon Telegr &Amp Teleph Corp &Lt Ntt&Gt, September 14, 2001: JP2001-251192 (1 worldwide citation)

PROBLEM TO BE SOLVED: To perform preliminary selection in conjugate structure vector quantization.SOLUTION: In a conjugate structure vector quantization method, the synthesized vector of two code vectors taken out from respective code books storing the two code vectors and a vector whose quantizatio ...


10
Moriya Takehiro, Iwagami Naoki, Jin Akio, Mori Takeshi: Voice/musical sound signal coding method and recording medium stored with program to execute the method. Nippon Telegr &Amp Teleph Corp &Lt Ntt&Gt, November 30, 2001: JP2001-331198 (1 worldwide citation)

PROBLEM TO BE SOLVED: To provide a voice/musical sound coding method in which quality deterioration of voice/musical sound reproduced signals is suppressed based on a given amount of information and a signal band.SOLUTION: Voice/musical sound signals are converted into frequency region components in ...