Signal compressing apparatus

1. A signal reproducing apparatus comprising:

means for reproducing an encoding-resultant signal of a predetermined recording-medium format from a digital disc including a DVD, the encoding-resultant signal containing audio information resulting from quantization of an audio signal including a monaural channel audio signal at a quantization degree higher than a degree of quantization for a CD and at a quantization sampling frequency higher than that for a CD, the quantization sampling frequency including 96 kHz;

means for decoding the reproduced encoding-resultant signal into a formatting-resultant signal corresponding to a predetermined format for a digital disc including a DVD, the formatting-resultant signal including segments corresponding to user data areas prescribed in the predetermined format, a compression-resultant-signal being placed in the segments of the formatting-resultant signal;

means for deformatting the formatting-resultant signal into the compression-resultant signal;

means for expanding the compression-resultant signal into a quantization-resultant signal by a Huffman decoding process; and

an output circuit converting the quantization-resultant signal into the audio signal including the monaural channel audio signal.

2. A signal recording apparatus comprising:

means for quantizing an input audio signal including a monaural channel audio signal into a quantization-resultant signal at a quantization degree higher than a degree of quantization for a CD and at a quantization sampling frequency higher than that for a CD, the quantization sampling frequency including 96 kHz;

means for compressing the quantization-resultant signal into a compression-resultant signal by a Huffman encoding process;

means for formatting the compression-resultant signal into a formatting-resultant signal corresponding to a predetermined format for a digital disc including a DVD, the formatting-resultant signal including segments corresponding to user data areas prescribed in the predetermined format, the compression-resultant signal being placed in the segments of the formatting-resultant signal;

means for encoding the formatting-resultant signal into an encoding-resultant signal of a predetermined recording-medium; and

means for recording the encoding-resultant signal on a digital disc including a DVD.

3. A signal recording apparatus as claimed in claim 2 , wherein the compressing means comprises means for dividing the quantization-resultant signal into components corresponding to divided frequency bands respectively, and means for compressing the components according to frequency-band-dependent compression characteristics depending on a predetermined auditory sensation model.

4. A signal reproducing apparatus comprising:

means for reproducing an encoding-resultant signal of a predetermined recording-medium format from, a digital disc including a DVD, the encoding-resultant signal containing audio information resulting from quantization of an audio signal including a monaural channel audio signal at a quantization degree higher than a degree of quantization for a CD and at a quantization sampling frequency higher than that for a CD, the quantization sampling frequency including 96 kHz;

means for decoding the reproduced encoding-resultant signal into a formatting-resultant signal corresponding to a predetermined format for a digital disc including a DVD, the formatting-resultant signal including segments corresponding to user data areas prescribed in the predetermined format, a compression-resultant signal being placed in the segments of the formatting-resultant signal;

means for deformatting the formatting-resultant signal into the compression-resultant signal;

means for expanding the compression-resultant signal into a quantization-resultant signal by one of an orthogonal decoding process and a Huffman decoding process; and

an output circuit converting the quantization-resultant signal into the audio signal including the monaural channel audio signal.