|Apparatus for high-speed recording compressed digital data with increased compression
|Feb. 7, 1995/ July 31, 1992
|Method of stripping out redundant information in ATRAC for further compression into a variable bit rate stream (for recording to a high cost storage device e.g. IC card memory).
|An apparatus for high-speed recording compressed digital data with additional bit reduction. The apparatus makes a recording, on a recording medium, of a recording signal in response to compressed digital data representing an audio information signal. The recording, upon reproduction from the recording medium, conversion to an analog signal, and reproduction of the analog signal, is for perception by the human ear. The compressed digital data has a constant bit rate. The apparatus includes a device that receives the compressed digital data, and a device that derives the recording signal by removing redundant bits from the compressed digital data. Redundant bits are bits that make no difference to quantization noise perceived by the human ear. Finally, the apparatus includes a device for recording the recording signal on the recording medium. The recording signal having a variable bit rate. In a second embodiment, the apparatus also includes a device that reproduces the compressed digital data from a another recording medium, enabling compressed digital data to be high-speed copied from the other recording medium.