Blocking artifacts reduction in block-based Dual-Tree Complex Wavelet transform

We propose a new method to reduce blocking artifacts in an encoded image by block-based dual-tree complex wavelet. In this paper, we describe a cause of blocking artifacts of the block-based approach and focus on a method for finding sparse representations from redundant complex coefficients. The proposed method offers minimal transform operation performing on the same resolution for an input image. Experimental results show that the proposed method reduces blocking artifacts that are observed along block boundaries and thus improves the visual quality.