Patent ID: 7245234

Claim:
A method of encoding digital signals composed of at least two channels, the method comprising: dividing a multi-channel digital signals into a predetermined number of frequency bands; detecting a most similar or relatively similar band among low-frequency bands less than a predetermined frequency, for each high-frequency band equal to or larger the predetermined frequency among the frequency bands; calculating a feature value from each of the high-frequency bands; performing a first operation using a first channel signal among the multi-channel signals to generate a first signal and performing a second operation using a combination of the first channel signal and a second channel signal among the multi-channel signals to generate a second signal; quantizing a signal that belongs to the low-frequency bands less than the predetermined frequency among the first and second signals and the calculated feature values of the high-frequency bands; and generating bitstreams using information on the detected similar low-frequency band, the quantized low-frequency band signal, and the quantized feature values of the high-frequency bands.