数字加网迟滞系数的研究

Research on Hysteresis Coefficient of Digital Screening

在输出反馈误差扩散法的基础上,提出了一种修正的调频调幅数字加网算法即带迟滞系数曲线的输出反馈误差扩散法。首先综合分析峰值信噪比与人眼主观感受,得到迟滞系数和图像不同阶调之间的规律,然后根据迟滞系数的拟合曲线得到其近似方程。实验结果表明,该算法能够有效抑制传统误差扩散调频加网中的网点扩大现象,并提高了图像的细节再现能力。

Based on Error Diffusion with Output Dependent Feedback, a revised amplitude modulation/frequency modulation（AM/FM）screening algorithm is suggested, that is, Error Diffusion with Output Dependent Feedback with H Curve. The laws between the hysteresis coefficient and the images of different tones are obtained first via the comprehensive analysis of peak value information noise ratio and human eye subjective sense, and then, the approximate equation is obtained in terms of the fitting curves of hysteresis coefficients. The experimental results indicate that this algorithm is able to effectively inhibit the dot gain phenomena in traditional error diffusion FM screening and that the reappearance ability of image details is improved.