Investigation and development of an atlas of optimal configurations, standard sizes, and areas of raster elements and basic link fragments for the synthesis of color halftone images

Results of investigation and development of methods for the synthesis of halftone images and computer and laser modern information technologies are presented. A completely new technology is proposed. Translated from Kibernetika i Sistemnyi Analiz, No. 2, pp. 134–143, March–April, 2000.     

An image segmentation method using histograms and the human characteristics of HSI color space for a scene image

Image segmentation is an important subject for image recognition. Here, we propose a new image segmentation method for scene images. The proposed segmentation method classifies images into several segments based on the human visual sense and achromatic color. We calculate the histograms of the image for each component of the hue, saturation, and intensity (HSI) color space, and obtain three results of image segmentation from each histogram. We consider achromatic colors in order to decrease the number of regions. We compare the results of the proposed method with those of the k-means methods for the effectiveness of the proposed method. This work was presented, in part, at the 10th International Symposium on Artificial Life and Robotics, Oita, Japan, February 4–6, 2005     

沙尘降质图像清晰化算法

目的 沙尘环境中获取的图像存在颜色失真、对比度低等问题,不利于人眼辨识以及进一步的图像处理。为解决沙尘降质图像的这些问题,提出一种新的基于颜色调整和对比度增强的沙尘降质图像的增强算法。方法 沙尘降质图像增强要解决两个问题,即颜色偏移和对比度增强。基于沙尘降质图像的的颜色直方图存在的集中性、顺序性以及偏离性等特性,使用高斯模型分别对各通道颜色进行建模,进而进行颜色调整。针对颜色调整后的图像存在的整体灰暗,对比度低以及噪声等特点,利用改进的基于奇异值分解的增强算法,从而有效地增加图像对比度并抑制噪声。结果 为了验证本文算法的有效性,与带有色彩恢复的多尺度Retinex算法、GUM算法、Tarel算法、融合算法4种方法进行了对比。从增强结果可以看出,本文算法能够有效解决降质图像的颜色偏移和对比度低的问题,并增强图像的整体视觉效果。结论 本文算法充分利用沙尘降质图像三通道颜色直方图分布的特点,能够快速高效地实现颜色校正,并通过图像频域的奇异值信息进一步提升图像的对比度。经过多幅沙尘降质图像清晰化实验验证,表明本文方法能够实现对不同程度沙尘降质图像的增强,具有较强的适用性。     

基于离散余弦变换彩色图像的数字水印研究

为了在彩色图像中嵌入彩色数字水印,同时保持原始彩色图像的完整性及健壮性,提出基于空间域和频率域间转换,配合RGB色彩系统,利用离散余弦变换将图像的空间域表示转换为频率域,将彩色数字水印频域系数经适当处理后嵌入图像的低频部分,使嵌入的彩色数字水印能抵抗各种图像处理时的破坏.实验结果表明:应用该方法嵌入彩色数字水印,不仅不破坏原始彩色图像品质,而且能抵抗外界的破坏,成功取回所嵌信息.     

模糊形态联想记忆网络抗随机噪声研究及应用

利用灰度图像分解的思想,结合模糊形态联想记忆网络的方法,提高了模糊形态联想记忆网络对随机噪声的抗噪能力。成功地解决了灰度图像在含有随机噪声时的模糊联想记忆问题,并把该方法推广到对彩色图像的处理,从而给出了一种较好地恢复含噪灰度图像和彩色图像的途径。通过实验,验证了该方法的良好性能,取得了较理想的结果。     

利用图像颜色特征与纹理特征进行图像检索

基于内容的图像检索主要是利用图像的特征,如:颜色直方图、纹理、形状等来进行检索,这种方式能够提高检索的效率与准确率.利用图像的颜色信息与利用快速傅立叶变换来提取纹理特征相结合的方法来进行图像检索,该方法一方面可以反映图像的全局特征,另一方面又反映了图像的局部特征,且具有对图像检索的旋转不变性.     

Detecting and Measuring Fine Roots in Minirhizotron Images Using Matched Filtering and Local Entropy Thresholding

An approach to automate the extraction and measurement of roots in minirhizotron images is presented. Two-dimensional matched filtering is followed by local entropy thresholding to produce binarized images from which roots are detected. After applying a root classifier to discriminate fine roots from unwanted background objects, a root labeling method is implemented to identify each root in the image. Once a root is detected, its length and diameter are measured using Dijkstra’s algorithm for obtaining the central curve and the Kimura–Kikuchi–Yamasaki method for measuring the length of the digitized path. Experimental results from a collection of peach (Prunus persica) root images demonstrate the effectiveness of the approach.     

彩色人体图像的二值化方法

为了快速有效的对彩色人体图像进行二值化处理,提出了一种新的自适应二值化处理方法.该方法根据人体肤色特征,建立人体肤色模型;根据该模型,分割出肤色和非肤色,再直接转换成二值图像.由于人体肤色受到不同光照和环境的影响,人体彩色图像中的人体肤色值会有偏移.为了改善肤色模型适应不同环境和光照,在肤色分割过程中,采用了自适应Gamma校正方法.最后,给出了该方法的实验结果.实验结果表明,提出的彩色人体图像的二值化方法快速且有效.     

An efficient color and texture based iris image retrieval technique

This paper proposes a hierarchical approach to retrieve an iris image efficiently from for a large iris database. This approach is a combination of both iris color and texture. Iris color is used for indexing and texture is used for retrieval of iris images from the indexed iris database. An index which is determined from the iris color is used to filter out the images that are not similar to the query image in color. Further, iris texture features of those filtered images, are used to determine the images which are similar to the query image. The iris color information helps to design an efficient indexing scheme based on color indices. The color indices are computed by averaging the intensity values of all red and blue color pixels. Kd-tree is used for real-time indexing based on color indices. The iris texture features are obtained through Speeded Up Robust Features (SURF) algorithm. These features are used to get the query’s corresponding image at the top best match. The performance of the proposed indexing scheme is compared with two well known iris indexing schemes ( [Mehrotra et al., 2010] and [Puhan and Sudha, 2008]) on UPOL (Dobeš, Machala, Tichavský, & Posp?´šil, 2004) and UBIRIS (Proencca & Alexandre, 2005) iris databases. It is observed that combination of iris color and texture improves the performance of iris recognition system.     

航空影像色彩一致性处理算法研究

航空影像的色彩一致性处理,又称影像匀光匀色,是正射影像生产过程中的重要环节之一,本文从色彩学、统计学、人体视觉等多角度出发,通过适当地改变原始影像亮度、对比度,提出了解决影像中大面积雾霭的方法,对于影像拼接之后出现的不同影像间色彩反差明显的现象,通过调整影像统计直方图,取得了很好的效果。     

高斯颜色模型在瓷片图像分类中的应用

由于RGB颜色空间不能很好贴近人的视觉感知,同时也缺少对空间结构的描述,因此采用兼顾颜色信息和空间信息的高斯颜色模型以获取更全面的特征,提出了一种基于高斯颜色模型和多尺度滤波器组的彩色纹理图像分类法,用于瓷器碎片图像的分类。首先将原始图像的RGB颜色空间转换到高斯颜色模型;再用正规化多尺度LM滤波器组对高斯颜色模型的3个通道构造滤波图像,并借助主成分分析寻找主特征图,接着选取各通道的最大高斯拉普拉斯和最大高斯响应图像,与特征图联合构成特征图像组用以进行参数提取;最后以支持向量机作为分类器进行学习和分类。实验结果表明,与基于灰度的、基于RGB模型的和基于RGB_bior 4.4小波的方法相比,本文方法具有更好的分类结果,其中在Outex纹理图像库上获得的分类准确率为96.7%,在瓷片图像集上获得的分类准确率为94.2%。此方法可推广应用到其他彩色纹理分类任务。     

Fast Anisotropic Smoothing of Multi-Valued Images using Curvature-Preserving PDE's

We are interested in PDE's (Partial Differential Equations) in order to smooth multi-valued images in an anisotropic manner. Starting from a review of existing anisotropic regularization schemes based on diffusion PDE's, we point out the pros and cons of the different equations proposed in the literature. Then, we introduce a new tensor-driven PDE, regularizing images while taking the curvatures of specific integral curves into account. We show that this constraint is particularly well suited for the preservation of thin structures in an image restoration process. A direct link is made between our proposed equation and a continuous formulation of the LIC's (Line Integral Convolutions by Cabral and Leedom (1993). It leads to the design of a very fast and stable algorithm that implements our regularization method, by successive integrations of pixel values along curved integral lines. Besides, the scheme numerically performs with a sub-pixel accuracy and preserves then thin image structures better than classical finite-differences discretizations. Finally, we illustrate the efficiency of our generic curvature-preserving approach – in terms of speed and visual quality – with different comparisons and various applications requiring image smoothing : color images denoising, inpainting and image resizing by nonlinear interpolation.     

A multistage parallel-hierarchic network as a model of a neuronlike computation scheme

A three-dimensional network and its application to the analysis of images are described. This multilevel architecture studies partial correlations between structural components of an image. An algorithm is proposed that formalizes a new approach to the decomposition of images. An image is transformed so that each pixel contains information on the spatial structure of its neighborhood. The most correlated information is first formed, which ensures the resistance of the algorithm to small structural changes. Translated from Kibernetika i Sistemnyi Analiz, No. 2, pp. 114–133, March–April, 2000.     

Measuring the color capability of modern display systems

Historically displays used three colorants in an additive system. During that time, the CIE chromaticity diagram adequately illustrated color capability. Modern displays are not constrained by this additive architecture, and the diagram can fail in its purpose. This is demonstrated by analysis and a large number of display measurements. A device‐independent methodology using CIE 1976 L*a*b* color gamut volume is described that provides a robust means to determine the size of the color gamut. This methodology is then extended to the ‘gamut rings’ diagram as a solution for visualizing color capability that directly correlates to color gamut volume. It is further shown how the methodology can be applied to determine the intersection between two gamut volume boundaries.     

基于数字人彩色图像的三维重建算法研究

对数字人彩色照片数据进行高质量的实时三维表面重建提出了一种新算法。该算法利用交互分割平台提取出彩色体数据中单个器官的三维表面点集,再根据对二值体数据滤波后的灰度值计算灰度梯度估算得到表面点的法向量。最后用带颜色的表面点来描述器官的三维表面,利用显卡OpenGL接口对表面点集进行三维显示。在微机环境下对美国数字人照片数据集中的肝脏和肺部两个器官进行了三维重建,在保证图像质量的前提下重建速度超过25帧/s。提出的算法能对高分辨率的彩色体数据进行高质量的实时三维表面重建。     

一种改进的图像色彩迁移方法

传统色彩迁移方法的迁移效果依赖于主观评价,且应用局限性大。为此,提出一种改进的图像色彩迁移方法。通过亮度拟合、分类筛选等操作从多幅源图像中选出与目标图像最匹配的参考色彩区域,针对彩色图像,采用隶属度概率进行平滑处理,利用参考色彩区域的颜色分量均值和方差,计算迁移合成值。针对灰度图像,对颜色分量进行归一化处理,划分灰度等级,引入Sigmoid加权实现迁移合成。实验结果表明,改进方法在视觉效果和客观评价方面都有较好的表现。     

遗传算法在分形图案自动化设计中的应用

遗传算法是一种基于生物自然选择与遗传机理的随机搜索与优化方法.为了自动设计出大量复杂美丽且符合用户需求的分形艺术图案,分析了影响分形图效果的各种因素,重点分析颜色选择对分形图案优劣的重要性,提出了利用交互式遗传算法对分形颜色进行遗传操作的方法,从而快速得到满足用户需求的设计图案.实验结果表明,采用该算法,用户能很快设计出自己喜欢的分形图案,并为研究分形图的结构特征提出了一种简洁有效的方法.     

基于GFCMA算法的医学彩色图像分割

医学图像分割是医学图像分析的关键步骤,经典的模糊C-均值聚类算法(FCM)是常用方法,但其依赖于初始聚类中心的选择,通常存在局部收敛的缺陷。通过与遗传算法(GA)结合而成的遗传模糊C-均值聚类算法(GFCMA),采用RGB颜色空间,能够得到全局最优解,并在此基础上实现了医学彩色图像分割和特定目标提取,取得良好分割效果。     

基于Perlin噪声的云生成系统

利用Perlin噪声建立云图像、用指数函数对云图像进行锐化、得到了云彩灰度图像;通过HLS颜色模型将灰度图像转换成彩色云彩图像;改变参数能模拟不同气候条件下的云彩效果.实验表明:运用OpenGL开发工具和纹理映射方法将云彩置入3维虚拟环境中,能在PC机上产生了逼真的云彩效果.     

一种新的真彩色图像隐写分析方法

本文通过分析LSB隐写对真彩色图像像素分量和统计特性的影响,提出了一种基于分量和频率相关的24位真彩色图像检测方法。该方法根据对载密图像再次隐写后其分量和的频率相关量趋于均匀的统计特征,构造衡量相邻分量和频率相关性的统计量来判断隐秘信息的存在。实验结果表明,该方法可以获得优于RQP方法的检测性能与计算复杂度。