Matsushita Electric Industrial Co., Ltd.

Katsushi Yamada

Yuji Kaihotsu

Toshikazu Chiba

Herein disclosed is a function-variable type DSP apparatus comprising: a storage section for storing a plurality of DSP microprogram parts; and a plurality of DSP executing sections each for executing the DSP microprogram parts to implement a DSP function, each of the DSP microprogram parts being executable by each of the DSP executing sections to perform a set of steps necessary to implement a DSP base function forming part of a DSP function, whereby the DSP executing sections are operative to receive the DSP microprogram parts simultaneously from the storage section, and selectively execute the DSP microprogram parts in a sequence to respectively implement desired DSP functions.

Function-variable type digital signal processing apparatus, and method of and program for controlling the same

A sound reproduction apparatus for a vehicle comprises: a sound source for generating a sound signal; a sound reproduction portion for reproducing a sound from the sound signal into a compartment of the vehicle; a microphone, provided in the compartment, for detecting the sound transmitted in the compartment and environmental sound noise and for generating a sound detection signal; a detection portion for detecting a magnitude of the environmental sound noise by detecting a difference between magnitudes of the sound signal and the sound detection signal; and a volume control portion for effecting volume controlling of the sound signal according to the magnitude of the environmental sound noise from the detection portion. An equalizing portion substantially equalizing gains of signal paths of the sound signal and sound detection signal supplied to the detection portion in a substantially silent condition of the compartment is provided. For accurate equalizing of gains, a reference sound signal source is provided. A part of frequency range of the sound signal is enhanced according to the sound noise. The volume controlling with the environmental sound noise is modified according to a peak level, an external volume control signal. The noise level may be classified. A large change in the volume within a short interval is avoided.

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Kanagawa-ken, Japan

Katsushi Yamada