光谱反射率重建中代表颜色分步选取方法

光谱反射率重建一般指采用标准色卡上的颜色样本,对成像系统进行光谱表征(Spectral character-ization),进而从系统响应中精确地求出物体表面的光谱反射率.由于标准色卡的颜色样本数量较大,在实际成像系统中使用时有诸多不便.考虑到颜色样本之间存在较大冗余,可从中选出具代表性的少数样本用于光谱表征.针对已有方法未考虑实际成像系统特性的不足,文章提出了一种代表颜色的分步选取算法,即首先通过假设一个虚拟成像系统,根据全局误差最小的原则,挑选出部分最具代表性的颜色,估计出实际成像系统的光谱响应函数,然后在此基础上继续选择其余的代表颜色.实验表明,对于窄带多光谱成像系统及宽带彩色扫描仪而言,文章提出的方法在光谱精度及色度方面均明显优于先前方法.     

Colorant Formulation Using 3 - layer Artificial Neural Networks

The colorant formulation using artificial neural networks (ANN) was investigated in this study. A simple 3 -layer, input - hidden - output system was constructed for the recipe formulation of one - , two - , and three -dye mixtures. Comprehensive tests were carried out to explore the properties of a 3 - layer simple ANN systematically . These properties include number of neurons in the hidden layer, learning rate of the network, momentum factor of the network, as well as the number of epochs for the learning process. The tests show accurate results for one - and two - dye mixtures while less accurate but comparable results to conventional colorant formulation systems for three - dye mixtures. It is also found that the optimum values of the neural network parameters are important towards the accuracy of the colorant formulation.     

活性染料废水对环境污染程度的预测

近年来,公众对保护环境的意识不断提高,因而令政府更关注环境污染的问题。为了保障市民的健康及保护生态环境,香港政府便制订了更严格的环保法例及废水排放标准,因此在染色时,厂商不但需要考虑染色成本及产品的坚牢度,更要考虑染料的环境属性,从而减低染色废水对环境的污染及符合政府制订的排放标准。如果能对染料的环境属性预先进行评估,那么染色废水对环境污染的程度便可于染色前预测得到,从而可于染色前选择一些污染度较低的染料进行染色。但由于不同染料类别的废水有不同的特性,因此,在这研究内,我们便选择了活性染料作为分析对象。     

Application of Modern Colour Measurement Dervices in Coloration Industries

In colour measurement ralated industry, reflectance spectrophotometer is the one of the popular measuring machine for measuring colour and quality control. Colour communications is frequently confusing. This is because the colour appearance is subject to the influence of at least three different phenomena: the light source, the object and the visual system. The variation in either the radiant quantity or the spectral distribution of the source can alter the observed colour. Because of this reason, the objective quantitative tool, colour measurement equipment and communication method; become more important in evaluating of the colour. In fact, based on the advanced in computer system and electronic device, the colour measurement becomes more and more accuracy, especially in spectrophotometer measurement. In this paper, we will focus on the review of modern spectrophotometers in coloration industries.     

一种彩色喷墨打印机的颜色特性化方法

为研究普通彩色喷墨打印机的颜色特性化,分析了打印过程中的两个主要步骤,即墨水分色过程和介质上的呈色过程,并提出较为精确的光谱预测模型.呈色过程采用基于简单点增益的(YNSN)模型和基于复杂点增益的改进型YNSN模型.为解决打印机的墨水分色无法直接控制的问题,构造了色度误差目标函数,利用非线性优化求解图像红绿蓝数值对应的...