基于几何活动轮廓模型初始轮廓自动分割方法的研究

提出一种几何活动轮廓模型初始轮廓自动分割的方法。此方法综合利用了分水岭算法以及几何活动轮廓模型算法，通过利用人脸的肤色特征、结构特征等逐级判别原理，从而实现了自动分割的目的。实验结果表明，采用此方法很好地实现了目标对象轮廓的自动分割，基本可达到与人工干预相近的效果。此方法同样可以广泛应用干人脸检测、图像自动分割、视频监控系统等领域。     

扫描地形图中等高线的识别

针对一般质量地形图的扫描过程中颜色混淆和错误现象比较严重,以致于在彩色分割等高线时不仅由于其自身与其他地图符号交叉或交叠而形成的断裂变得更为复杂,而且等高线间的密集排列也会造成粗线现象（等高线彼此粘连在一起）等问题提出一种有效的针对一般质量地形图中等高线的识别方法.该方法具有3个特点：一是彩色地图分割中使用关键颜色集技术以补偿混淆和错误颜色;二是在原图像中等高线出现断裂和粗线的地方采用局部窗口再分割算法,以解决等高线断裂和彼此粘连问题;最后利用等高线的全局拓扑性质滤波得到正确的等高线.实验结果表明该方法对于一些高质量和一般质量的地形图中等高线的识别都具有一定的应用潜力.     

轮廓矩不变量及其在物体形状识别中的应用

为了有效地刻画物体的形状特征，在基于区域的Hu矩不变量的基础上，构造了一种基于物体轮廓曲线的新的矩不变量，即轮廓矩不变量。该不变量不仅独立于物体本身的颜色和灰度级，而且具有平移、旋转和尺度不变性，因此可将轮廓矩不变量应用于物体形状的识别，为了能快速地进行物体形状识别，还讨论了小波边缘检测和轮廓的获取问题及其算法。实验表明，基于这种轮廓矩的识别算法具有很好的识别率。     

隐与现——论色彩交界现象的视觉意义及对平面广告的影响

广告中色彩交界产生的融合或闪烁现象可以直接影响受众的视注意点,根据视注意点的不同,得出一个结论:交界融合的色彩适合应用在含有大量信息的印刷平面广告当中,而交界闪烁的色彩适合应用在户外广告中。     

探析色彩在多媒体课件中的应用

针对目前大多数多媒体课件由任课教师自行完成的现状,对课件设计中色彩与文字设计的一些基本技巧进行了归纳,通过对色彩的特性、色彩的形成和对比规律、色彩间的相互关系、色彩的视觉效果及心理联想等的描述来探讨多媒体课件界面色彩的设计原则。     

Color recovery of black-and-white halftoned images via categorized color-embedding look-up tables

A new method of recovering the original colors of black-and-white (B&W) halftoned images with homogeneous dot patterns is proposed. The conventional inverse halftoning method, which uses a look-up table (LUT), can establish the relation between the halftoned patterns and the corresponding gray levels, while the conventional reversible color to gray conversion method can recover the original colors from a given color-embedded gray image. To accomplish our goal of original color recovery from B&W halftoned patterns, an approach of combining the conventional inverse halftoning and reversible color to gray conversion is presented in this paper. Differently from the conventional method of inverse halftoning via LUT, four LUTs categorized according to the red, green, blue, and gray reference colors are designed to more accurately map a specific B&W halftone pattern into the corresponding color-embedded gray level based on the observation that the shapes of the halftone patterns depend on input colors, thereby increasing the color recovery accuracy. Also, a color mapping method based on a linear regression which models the relation between the recovered colors and the original colors is introduced to adjust the initially recovered colors more closely to the original colors. Experimental results show that unknown original colors can be recovered from B&W halftoned images via the proposed method.     

论色彩心理学在环境艺术设计中的应用

本文主要讨论环境艺术设计中如何利用色彩心理学进行色彩设计,安置基调色、配合色以及各种色彩的调配。     

Modelling of color perception of different eye colors using artificial neural networks

Color is a subjective term that changes according to each person’s view. We should define color physically to work with it in terms of printing or any other professional study. However, enabling the observation of color in terms of sales, marketing, product design, and development is as important as product and its packaging. The perception of color and tendencies to colors will be different for people of different eye colors. In this study, different color samples will be shown to five different eye colors of hazel, green, blue, brown, and black eyes both of men and women. The aim of the study is to determine which eye color is more perceived and adopted by which eye color using artificial neural network (ANN) for between 6 and 17 ages. By considering these determinations, it has been studied with graphical and statistical illustrations how different eye color groups prefer colors, how much they are able to recognize primary and secondary colors, and to what extent various eye colors are able to perceive RGB and CMY colors correctly.     

Wide gamut LCD using locally dimmable four‐primary‐color LED backlight

This paper proposes a wide gamut LCD using locally dimmable four‐primary‐color (4PC) LED backlight. Although the color gamut of LCDs has been improved in recent years, it is insufficient to reproduce all the colors in the real world. The objective of this paper is to propose a wide gamut LCD that reproduces all the colors in the real world while keeping the cost increases to a minimum. We evaluated the color gamut reproduced by LEDs of multiple primary colors and selected cyan as the optimal color to be added to the three primary colors to reproduce all the colors in the real world. Therefore, we designed an LED backlight consisting of an additional only‐cyan LED with three‐primary‐color LEDs and developed a prototype LCD with 4PC LED backlight. Furthermore, we developed a local dimming algorithm for the 4PC LED backlight. As a result, we confirmed that the prototype LCD with the 4PC LED backlight is able to cover almost all the colors in the real world and also able to display natural images with highly saturated colors by local dimming.     

一种8色液晶显示屏幕的色彩丰富改进方案

液晶屏目前已经深入各个电子制造业领域中，小到手机、PDA，大到液晶大屏幕和航空应用领域。液晶屏以其优良的性能，在显示器领域占据了一席之地。目前市面上的液晶屏幕以8色为多。其特点是在数据区中以3个bit表示一个像素，这样就可以从000～111总共表达8种颜色，也就是传统的RCB表达法的最简式：这样的液晶屏幕操作简单，价格低廉，在低端场合最为适用。但缺点也十分突出，就是可以显示的颜色太少，本来仅有的8种颜色中，可能还有其中的一种或几种在某个设计时不能用，比如会和界面风格抵触等等原因：这样，可以使用的颜色就更少了。如何能在不大量增加成本和系统开销的情况下增加屏幕可以显示的颜色数，就值得工程人员研究考虑了，本文将介绍一种改进方法．     

Algorithms for Coloring Quadtrees

We describe simple linear time algorithms for coloring the squares of balanced and unbalanced quadtrees so that no two adjacent squares are given the same color. If squares sharing sides are defined as adjacent, we color balanced quadtrees with three colors, and unbalanced quadtrees with four colors; these results are both tight, as some quadtrees require this many colors. If squares sharing corners are defined as adjacent, we color balanced or unbalanced quadtrees with six colors; for some quadtrees, at least five colors are required.     

一种可调节的多级颜色量化算法

针对当量化图像的颜色数量较少时如何调节颜色层次和微弱颜色,本文提出了一种新颖的多级颜色量化算法.根据Kohonen自组织神经网络和线性像素置换计算第一级调色板;然后多次迭代找出最相似的颜色对,删除其中的一个,得到第二级调色板;最后根据调色板中颜色的像素数量和与基色距离的加权和,选出最终的代表颜色.实验结果表明,该算法能够通过设置适当的像素取样率、像素数量权重和与基色的距离权重而有效地选择满足不同需要的量化结果,并且保持较好的量化图像质量.     

Non‐metamerism of boundary colors in multi‐primary displays

Abstract— A control sequence gives the intensities of the primaries for a pixel of a display device. The display gamut, i.e., the set of all the colors that a display can produce, is a zonohedral subset of CIE XYZ space and contains both boundary and interior colors. Displays with four primaries or more exhibit metamerism, in which different control sequences produce colors that appear identical to an observer. This paper shows mathematically that, provided no three primaries are linearly dependent, metamerism can only occur for interior colors. When there are four or more primaries, metamers can always be found for interior colors. A color on the gamut boundary, by contrast, is only produced by a unique control sequence. The proof used for displays can be extended to object‐color solids, to show that optimal colors, which are on the boundary of an object‐color solid, have unique reflectance functions.     

Algorithms for Coloring Quadtrees

Abstract. We describe simple linear time algorithms for coloring the squares of balanced and unbalanced quadtrees so that no two adjacent squares are given the same color. If squares sharing sides are defined as adjacent, we color balanced quadtrees with three colors, and unbalanced quadtrees with four colors; these results are both tight, as some quadtrees require this many colors. If squares sharing corners are defined as adjacent, we color balanced or unbalanced quadtrees with six colors; for some quadtrees, at least five colors are required.     

Color discrimination enhancement for dichromats using self-organizing color transformation

Color deficient persons, especially dichromats, have difficulty in discriminating certain kinds of colors. To help dichromats discriminate colors better, a color transformation method is proposed. The method utilizes the redundancy of color information, changing the colors of a scene into discernable ones for dichromats. The self-organizing map (SOM) algorithm is used to build a nonlinear color map, maintaining the neighboring relations between colors. Results of both subjective observation and quantitative evaluation show that the method can effectively enhance the color discrimination for dichromats. This study provides a new approach to rectify color vision deficiency.     

A CAD System for Color Design of a Car

We have developed a color CAD system which enables a color designer to evaluate and create body colors of a car on a graphic display and put this system into practical use. The system has three features; generating realistic images comparable to photography to satisfy the car designer's needs, through close analysis of the physical phenomena taking place in the real environment, reproducing the desired colors very accurately on a CRT monitor, through analysis of the CRT colorimetric characteristics of reproducing the specified colors in response to the input signals, and utilizing a parallel computer to generate realistic images at a high speed and to control colors through interactive operation. Application of the CAD system reported here to the field of color design made it possible to fully evaluate and create body colors by means of computer graphics, replacing the conventional method which requires the painting of clay models or prototype cars.     

基于色彩与形状的机器人足球识别方法

机器人能够快速、正确地识别足球十分重要.由于RoboCup对颜色进行了严格地规定,所以常见的识别方法仅基于色彩,该法的不足之处是容易受到等场条件的影响.利用Matlab中的图像处理函数,提出了一种基于色彩和形状的识别足球的新方法,即首先通过色彩筛选过滤图像中较多的无关目标,在对图像进行边缘检测后再采用欧拉数以及面积大小进行二次过滤,最后利用偏心率对足球进行识别.实例表明该法简单、有效、鲁棒性强.     

New display concept for realistic reproduction of high-luminance colors

A new display concept for reproduction of high-luminance colors based on a liquid crystal display has been developed using a brighter backlight unit and color mapping algorithms. The new concept is able to display brighter colors close to a peak luminance of a display white than conventional displays so that realistic scene of brighter colors is better reproduced. It may also be one of the future display solutions needed to extend the color gamut in the direction of brighter colors, which is a principal limitation in conventional displays even in high-dynamic range display systems. With the new concept, an xvYCC- (extended-video YCbCr) compatible display can be easily realized.     

基于颜色直方图熵值及分块主色的图像检索

为了克服在检索相同背景中物体颜色不同的图像时无法利用颜色特征而必须利用物体的形状特征这一缺陷,并进一步提高图像的检索效果,本文提出了一种基于颜色直方图熵值及分块主色的图像检索方法。实验结果表明,该方法不仅可以提高图像检索的查准率与查全率,而且对于检索相同背景中物体颜色不同的图像时只利用颜色特性即可达 检索目的。     

An adjustable algorithm for color quantization

Color quantization is an important technique in digital image processing. Generally it involves two steps. The first step is to choose a proper color palette. The second step is to reconstruct an image by replacing original colors with the most similar palette colors. However a problem exists while choosing palette colors. That is how to choose the colors with different illumination intensities (we call them color layers) as well as the colors that present the essential details of the image. This is an important and difficult problem. In this paper, we propose a novel algorithm for color quantization, which considers both color layers and essential details by assigning weights for pixel numbers and color distances. Also this algorithm can tune the quantization results by choosing proper weights. The experiments show that our algorithm is effective for adjusting quantization results and it also has very good quality of quantization.