Edge-Directed Error Diffused Digital Halftoning: A Steerable Filter Approach

In this paper the edge-directed error diffused digital halftoning in noisy media is analyzed. It is known that there occurs error in transmitting data through a communication channel due toaddition of noise, generally additive white Gaussian noise (AWGN). The proposed work employs Steerable stochastic error diffusion (SSED) approach, a hybrid scheme that utilizes the advantages of Steerable filter for edge detection purpose and five neighbor stochastic error diffusion (FNSED) approach for error diffusion purpose. Analysis of different methods of edgedetectionand error diffusion in the presence of zero mean AWGN with different values of variance has also been made. The results show that the proposed scheme produces halftones of better quality in the presence of even large value of noise variance compared to other approaches of edge detection and error diffusion.