Audio-signal correction apparatus, audio-signal correction method and audio-signal correction program

摘要

Sequential digital audio signals are received to calculate a difference between each currently sampled digital audio signal and another digital audio signal sampled at one sampling period before each currently sampled digital audio signal. Differences for the sequential digital audio signals are stored. The number of digital audio signals consecutively clipped is counted in the received sequential digital audio signals. A specific difference is retrieved, from the stored differences, for a digital audio signal sampled at a specific number of sampling periods before each clipped digital audio signal. The specific number of sampling periods is determined based on the counted number of digital audio signals consecutively clipped. Each clipped digital audio signal is corrected based on the specific difference.

主权项

1. An audio-signal correction apparatus comprising:
a difference calculation and storage unit configured to receive sequential digital audio signals, to calculate a difference between each currently sampled digital audio signal and another digital audio signal sampled at one sampling period before each currently sampled digital audio signal, and to store differences for the sequential digital audio signals; a clip counter configured to count the number of digital audio signals consecutively clipped in the received sequential digital audio signals; a correction unit configured to retrieve a specific difference, from the difference calculation and storage unit, for a digital audio signal sampled at a specific number of sampling periods before each clipped digital audio signal, the specific number of sampling periods being determined based on the counted number of digital audio signals consecutively clipped, and to correct each clipped digital audio signal based on the specific difference; a first converter configured to convert each of the received sequential digital audio signals into a first analog signal; a second converter configured to convert the corrected digital audio signal into a second analog signal; an amplifier configured to amplify the second analog signal; and an adder configured to add the first analog signal and the amplified second analog signal; wherein each of the received sequential digital audio signals is composed of a first specific number of bits wherein the correction unit shifts the first specific number of bits to lower bits of a second specific number of bits larger than the first specific number of bits, and processes the second specific number of bits having the shifted first specific number of bits in correction of each clipped digital audio signal.