一种二阶混合调频网的新型加网模型  

A New Model of Secondary Order Hybrid FM Screening

作　　者：周啸[1] 史瑞芝[1] 

机构地区：[1]信息工程大学地理空间信息学院,河南郑州450052

出　　处：《测绘科学技术学报》2013年第6期652-657,共6页Journal of Geomatics Science and Technology

摘　　要：乘同余伪随机算法和二阶网点生成算法是两种以生成随机数为基本原理的调频加网算法,其随机数生成与算法模型和初始值的选取有关,两种算法有各自的特点。本文在分析了最优乘同余伪随机算法和二阶网点生成算法各自特点的基础上提出了一种新型加网模型,该模型能够有效解决印刷加网常见线条锯齿感、网点扩大等问题。首先分析了现有加网模型存在的缺陷,然后提出了模型建立的思路,确定了建立新型模型所使用的底层构架模型。通过对模型建立方法的分析,详细论述了点位右移法和点位左移法两种改进算法,以此为基础设计软件实现新型算法的加网功能。利用该软件处理原稿,通过模拟打样实验验证了新型模型的可行性及其具有的优势。Multiplicative congruence pseudo-random algorithm and secondary order dot generating algorithm are two algorithms which set on the principle of random numbers generating. In the two algorithms, the generating of ran- dom numbers is relevant to the selecting of algorithm model and initial value. In this paper, a new screening model based on optimal multiplicative congruence pseudo-random algorithm and secondary FM screening outlets is brought forward. This model can effectively solve the problems in printing such as line sawtooth, dot gain, etc. The flaws and disadvantages in common screening methods were firstly analyzed and the idea of modeling was brought for- ward.Then the needed bottom models to setting up the new model were confirmed. By analyzing the modeling meth- od, point right shift method and point left shift method were discussed and expounded in detail, on whose founda- tion the software with new screening functions was designed and realized. Finally, this software was used to perform simulative proofing experiment to testify the feasibility and superiority of the new model.

关 键 词：最优乘同余算法 二阶调频加网 混合加网 加网模型 随机数 

分 类 号：P288[天文地球—地图制图学与地理信息工程]