Boundary artifacts reduction in vector error diffusion

Color error diffusion can be classified into two types, namely, vector error diffusion and scalar error diffusion, according to the underlying quantization methods. Compared to scalar error diffusion, vector error diffusion is typically superior in overall image quality. However, it may occasionally introduce boundary artifacts. A color band, at a width of a few pixels to tens of pixels may appear along the edges. The artifacts are referred in literature to slow response for leading edges and smear for trailing edges, respectively. In this paper, we present a simple yet effective method for reducing the boundary artifacts.