Alleviating blocking artifacts via curve-fitting

Image enhancement in discrete cosine transform (DCT) domain, which has been widely utilized, is affected by blocking artifacts seriously. Various effective methods for reducing such blocking artifacts are paid much attention. A novel method for reducing the artifacts is proposed in this paper; the novelty of this method is developing a curve-fitting algorithm to alleviate blocking artifacts and a least-square based technique is adopted to estimate the coefficients for curve fitting. As a result, the blocking artifacts can be significantly alleviated. In addition, the color and contrast of resulted image can be kept as that in the adjusted image (with blocking artifacts). Experiments on different images demonstrate that the proposed algorithm can provide better results than that of the popular CES algorithm^[1] (Enhancement of color images by scaling the DCT coefficients) and has lower computational complexity.