Signal compressing apparatus

1. A signal expanding method comprising the steps of:

receiving an encoding-resultant signal of a predetermined recording-medium format from a DVD, the encoding-resultant signal containing audio information resulting from quantization of an audio signal including a multi-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;

decoding the received encoding-resultant signal into a formatting-resultant signal corresponding to a predetermined format for 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 formatting-resultant signal;

deformatting the formatting-resultant signal into the compression-resultant signal; and

expanding the compression-resultant signal into a quantization-resultant signal by a Huffman decoding process.

2. A signal expanding method comprising the steps of:

receiving an encoding-resultant signal of a predetermined recording-medium format from a DVD, the encoding-resultant signal containing audio information resulting from quantization of an audio signal including a multi-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;

decoding the received encoding-resultant signal into a formatting-resultant signal corresponding to a predetermined format for 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 formatting-resultant signal;

deformatting the formatting-resultant signal into the compression-resultant signal; and

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

3. A computer readable medium encoded with instruction capable of being executed by a computer for storing an encoding-resultant signal containing audio information which is recording on the recording medium by the steps of quantizing an input audio signal including a multi-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;

compressing the quantizing-resultant signal into a compression signal by a Huffman encoding process;

formatting the compression-resultant signal into a formatting-resultant signal corresponding to a predetermined format for 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;

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

recording the encoding-resultant signal on the recording medium.

4. A signal recording method for recording a recording medium as recited in claim 3 , wherein the method comprises the steps of quantizing an input audio signal including a multi-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;

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

formatting the compression-resultant signal into a formatting-resultant signal corresponding to a predetermined format for 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;

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

recording the encoding-resultant signal on the recording medium.

5. An apparatus for an optical disc, comprising:

a CD-DA decoder;

a DVD decoder;

a DVD-audio expansion decoder including Huffman decoding;

means for reading out a signal from the optical disc;

means for deciding which of a CD-DA, a DVD, and a DVD-audio the optical disc agrees with;

means for, when the optical disc agrees with a CD-DA, selecting the CD-DA decoder from among the CD-DA decoder, the DVD decoder, and the expansion decoder and using the CD-DA decoder to process the signal read out from the optical disc into a recovery signal;

means for, when the optical disc agrees with a DVD, selecting the DVD decoder from among the CD-DA decoder, the DVD decoder, and the expansion decoder and using the DVD decoder to process the signal read out from the optical disc into a recovery signal; and

means for, when the optical disc agrees with a DVD-audio, selecting the expansion decoder to process the signal read out from the optical disc into a recovery signal.