Fujitsu Corporation

Fumiaki Nishida

Hideaki Kurihara

Noboru Kobayashi

Naoji Fujino

A multi-channel signal processing apparatus comprises a memory unit, a signal processing unit for single-channel implementing predetermined signal processing using a memory region of the memory unit according to a signal processing program for single-channel, an address generation unit generating a first memory address for single-channel processing, a pointer adding unit adding a pointer value indicating the head of an unused memory region of the memory unit to the first memory address generated by the address generation unit each time the signal processing in the signal processing unit is completed to generate a second memory address, and an address selecting unit selecting either the first memory address or the second memory address as a real address for the memory unit, thereby enabling multi-channel signal processing having a high processing efficiency without adding a large modification to the signal processing program for single-channel.

Memory management apparatus in a multi-channel signal processor

Disclosed is an audio encoding apparatus for splitting an audio signal into a plurality of bands, allocating a number of quantization bits to each band and transmitting the audio signal of each band upon quantizing the audio signal by the number of allocated bits. The apparatus includes a bit allocation unit for (1) calculating an MNR for each band, where MNR is the ratio of an audio masking level M to a quantization noise level N, (2) comparing a set MNR with the smallest MNR from among the MNRs of the respective bands, (3) incrementing the number of quantization bits of the band that corresponds to the smallest MNR if the smallest MNR is smaller than the set MNR, and (4) performing allocation control for allocating quantization bits to each band until the smallest MNR becomes equal to or greater than the set MNR. A quantizer quantizes the audio signal of each band by the allocated number of quantization bits, and a bit-rate calculation unit decides a bit rate for transmission of audio data based upon the number of quantization bits allocated to each band.

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Kawasaki, Japan

Fumiaki Nishida