Patent ID: 7114072

Claim:
An apparatus for imbedding a watermark by using a linear prediction analysis, comprising: a linear prediction analyzing unit for receiving an original signal and detecting a prediction coefficient predetermined through the linear prediction analysis; a delay unit for receiving the original signal and delaying it by a predetermined time; a linear prediction analysis filtering unit for filtering the signal delayed in the delay unit by using the prediction coefficient detected in the linear prediction analyzing unit; a frequency area converting unit for converting the signal outputted from the linear prediction analysis filtering unit into a frequency area signal; a psychological acoustic modeling unit for receiving the original signal and gaining a masking threshold by employing a psychological acoustic model; a time-varying adaptation filtering unit for performing a control so that the signal outputted from the frequency area converting unit may have a magnitude approximate a magnitude the masking threshold gained in the psychological acoustic modeling unit; a time area converting unit for changing the signal outputted from the time-varying adaptation filtering unit to a time area signal; an error correction coding unit for receiving copyright information and providing an error correction function; a code generating unit for providing a code to the time area signal outputted from the time area converting unit response to a signal outputted from the error correction coding unit; and computing unit for adding and deducting the signal having the code provided from the code generating unit to/from the original signal response to a corresponding code, and producing a signal having an imbedding of the watermarks; wherein said psychological acoustic modeling unit receives the original audio signal and obtains the masking threshold as a threshold capable of sensing audio original sound in a frequency area by employing a psychological acoustic model.