US05301205 | Apparatus and method for data compression using signal-weighted quantizing bit allocation | |

Assignee | Sony Corporation | |

Assign./Filed | April 5, 1994/ Jan. 29, 1993 | |

Inventors | Tsutsui; Kyoya, Akagiri; Kenzo | |

Summary | ATRAC - includes detailed discussion of ATRAC's bit allocation method. | |

Abstract | A data compression apparatus for compressing a digital input signal to provide a compressed digital output signal. In the apparatus, a circuit derives plural spectral coefficients from the digital input signal, and groups the spectral coefficients into bands. An adaptive bit allocation circuit adaptively allocates a number of spectrum-dependent quantizing bits among the bands to allocate to each band a number of spectrum-dependent quantizing bits for quantizing each of the spectral coefficients in the band. The number of spectrum-dependent quantizing bits allocated to each band by the adaptive bit allocation circuit is determined according to the band magnitude, weighted depending on the band frequency. |