Patent ID: 7746964

Claim:
A signal processing apparatus comprising: a plurality of equalizing means each used for a corresponding frequency band among a plurality of frequency bands; controlling means for setting a gain value in each of the plurality of equalizing means; and signal processing means for processing an input signal by means of the plurality of equalizing means, wherein the controlling means determines a target gain value for each of the plurality of frequency bands; identifies one or more first frequency bands that are not influenced by gain leakage from one another and assigns a corresponding target gain value as a first gain value to each of the one or more first frequency bands; for each first frequency band of the one or more first frequency bands: obtains a value of gain leakage from the first frequency band to a second frequency band influenced by gain leakage from the first frequency band; sets a second gain value for the second frequency band in accordance with the value of gain leakage to the second frequency band and the target gain value corresponding to the second frequency band; updates the first gain value for the first frequency band in accordance with a value of gain leakage to the first frequency band from the second frequency band and the second gain value for the second frequency band; updates the second gain value in accordance with the value of the gain leakage from the first frequency band to the second frequency band and the first gain value updated in the act of updating; and to determine final gain values, repeats the acts of updating the first gain value for the first frequency band and updating the second gain value for the second frequency band until the first gain value and the second gain value satisfy a predetermined condition; and sets a final gain value for each of the frequency bands of the plurality of frequency bands in the corresponding equalizing means.