A Method of Digital Halftoning through Approximated Optimization of Scale-Related

We gain the scale-related characterization of the original image using the discrete wavelet transform. The boundary information of the image target is fused by the wavelet coefficients of the correlation between wavelet transform layer, which to increase the pixel resolution scale. We apply the inter-scale fusion method to gain fusion coefficient of the fine-scale, which take into account the detail of the image and approximate information, which the fusion coefficient are referred to as the weighting operator and to establish the boundary energy function. In the halftone process, each clustering uses the weighted least-squares method through energy minimization via Direct Binary Search algorithm, which to gain halftoning image. Simulation results on typical test images further confirm the performance of the new approach.