Abstract: A high quality speech is reproduced with a small data amount in speech coding and decoding for performing compression coding and decoding of a speech signal to a digital signal. In speech coding method according to a code-excited linear prediction (CELP) speech coding, a noise level of a speech in a concerning coding period is evaluated by using a code or coding result of at least one of spectrum information, power information, and pitch information, and various excitation codebooks are used based on an evaluation result.

Abstract: A speech coding apparatus comprises a repetition period pre-selecting unit for generating a plurality of candidates for the repetition period of a driving excitation source by multiplying the repetition period of an adaptive excitation source by a plurality of constant numbers, respectively, and for pre-selecting a predetermined number of candidates from all the candidates generated. A driving excitation source coding unit provides both excitation source location information and excitation source polarity information that minimize a coding distortion, for each of the predetermined number of candidates, and provides an evaluation value associated with the minimum coding distortion for each of the predetermined number of candidates.

Abstract: The present invention comprises: first periodicity providing means for emphasizing periodicity of a fixed code vector output from at least one fixed excitation code book by use of a first periodicity emphasis coefficient adaptively determined based on a predetermined rule; and second periodicity providing means for emphasizing periodicity of a fixed code vector output from at least one fixed excitation code book by use of a predetermined second periodicity emphasis coefficient.

Abstract: A high quality speech is reproduced with a small data amount in speech coding and decoding for performing compression coding and decoding of a speech signal to a digital signal.

Abstract: A high quality speech is reproduced with a small data amount in speech coding and decoding for performing compression coding and decoding of a speech signal to a digital signal.

Abstract: A speech encoding apparatus calculates encoding distortion of a noise-like fixed code vector and multiplies the encoding distortion by a fixed weight corresponding to the noise-like degree of the noise-like fixed code vector, calculates encoding distortion of a non-noise-like fixed code vector and multiplies the encoding distortion by a fixed weight corresponding to the non-noise-like fixed code vector, and selects the fixed excitation code associated with multiplication result with a smaller value.

Abstract: Drive sound source coding means, decoding means has a plurality of algebraic sound source coding means, decoding means having sound source position tables different in distribution lean of sound source position candidates in a frame, each algebraic sound source coding means, decoding means for referencing spectrum envelope information and coding the sound source of an input voice based on a sound source position selected from among the sound source position candidates in the sound source position table and a polarity and selection means for selecting the algebraic sound source coding means, decoding means with the smallest coding distortion from among the plurality of algebraic sound source coding means, decoding means and outputting code representing the drive sound source position output by the selected algebraic sound source coding means, and polarity.

Abstract: The present invention comprises: first periodicity providing means for emphasizing periodicity of a fixed code vector output from at least one fixed excitation code book by use of a first periodicity emphasis coefficient adaptively determined based on a predetermined rule; and second periodicity providing means for emphasizing periodicity of a fixed code vector output from at least one fixed excitation code book by use of a predetermined second periodicity emphasis coefficient.

Abstract: A speech encoding apparatus capable of averting the deterioration of synthesis speech quality in encoding the input speech and of generating a high-quality synthesis output speech through small quantities of computation. The apparatus includes a target speech generation part for generating from the input speech a target speech vector of a vector length corresponding to a delay parameter; an adaptive codebook for generating from previously generated excitation signals an adaptive vector of the vector length corresponding to the delay parameter; an adaptive code search part for evaluating the distortion of a synthesis vector obtained from the adaptive vector with respect to the target speech vector so as to search for the adaptive vector conducive to the least distortion; and a frame code generation part for generating an excitation signal of a frame length from the adaptive vector conducive to the least distortion.

Abstract: A speech coding and decoding apparatus for improving the quality of synthesized speech. A coding portion includes a filter for adding a short-term phase amplitude characteristic to an excitation signal, and a coding circuit for quantizing and coding a phase amplitude characteristic. A decoding portion includes a decoding circuit for decoding the coded phase amplitude characteristic, and a filter for adding the same phase amplitude characteristic as that in the coding portion. Thus, it is possible to synthesize high-quality speech with good reproducibility of the phase amplitude characteristic of an excitation signal.

Abstract: Easy testability and data security of an electrically erasable programmable read only memory (EEPROM) can be accomplished by disposing pads and an input/output (I/O) circuit providing addresses, data and control signals necessary for the EEPROM test on a semiconductor substrate and by disposing a two-level test I/O interception circuit consisting of an EEPROM device on the substrate such that once the testing is completed, unauthorized accessing is prevented from outside the semiconductor substrate as a result of having a built-in data security function. A microcomputer having this capability is provided with a central processing unit (CPU) for processing data, a memory, such as an EEPROM, which is internally communicating through a common bus (which transmits data, address and control signals) with the CPU, other than during a test mode, and first and second inhibition circuits which provide the security.

Abstract: A semiconductor integrated circuit device which inhibits the output of programmed data of its built-in memory to external terminals but outputs the result of a comparison of the programmed data with an input signal supplied from a first external terminal to a second external terminal.

Abstract: The present invention relates to a semiconductor device and a process for producing the same. The principal surface of a semiconductor pellet is provided with a plurality of first bonding pad electrodes arranged in a first arrangement state and a plurality of second bonding pad electrodes which are provided with substantially the same electric circuit functions as those of the corresponding first bonding pad electrodes and which are arranged in a second arrangement state that is different from the first arrangement state. By virtue of the above-described means, it is possible to connect together pad electrodes and mating external terminals of a mounting substrate in the same way regardless of whether the pellet is mounted according to the face-up or face-down method.

Abstract: A semiconductor integrated circuit device which inhibits the output of programmed data of its built-in memory to external terminals but outputs the result of a comparison of the programmed data with an input signal supplied from a first external terminal to a second external terminal.