DCT COEFFICIENT REQUANTIZATION METHOD TO REDUCE AN IMAGE TO A DEGREE OF A DESIRED BIT RATE AND IMPROVE IMAGE QUALITY

摘要

PURPOSE: A DCT(Discrete Cosine Transform) coefficient requantization method is provided to reduce an image to a degree of a desired bit rate and improve image quality by directly converting a DCT coefficient toward a trend of decreasing a requntization error. CONSTITUTION: An interval where an error can arise is determined and DCT coefficients having capability of a requntization error are searched in the interval(S10). A combination of the DCT coefficients searched is obtained, wherein the DCT coefficients have least capability of the requntization error(S20). The combination obtained is determined as a new requntization coefficient(S30).