基于视觉显著图的异性纤维彩色图像分割方法

为实现对棉花异性纤维自动视觉检测系统采集的彩色图像的精确分割,提出了基于视觉显著图的异性纤维彩色图像分割方法.通过计算颜色显著图,实现彩色异性纤维目标的识别;通过计算亮度显著图,实现灰色异性纤维目标的识别;将彩色和灰色目标进行融合,得到全部异性纤维目标.实验结果表明,该方法可以准确分割出异性纤维彩色图像中含有的各种异性纤维目标.通过比较发现,该方法在分割精度上明显优于其它方法,可以实现对异性纤维彩色图像的精确分割.     

基于低分辨率彩色指导图像的深度图像超分辨率重建

传统的以彩色图像为指导的深度图像超分辨率(SR)重建方法,参考图像必须为高分 辨率彩色图像,彩色图像的分辨率决定了深度图像的放大上限。同时,实际应用中可能只存在低 分辨率彩色图像,此时上述方法也不再适用。为此,探讨使用任意分辨率彩色图像为指导的深度 图像SR 重建方法。首先,使用大量不同类别的图像SR 算法对输入彩色图像进行上采样,得到 高分辨率彩色图像并以此作为指导图像,然后采用基于二阶总广义变分方法,将由低分辨率彩色 图像重建得到的图像作为正则约束项,添加图像边缘信息,构建目标函数,将深度图像SR 重建 问题转化为最优化问题,再通过原-对偶方法求解,最终得到高分辨率深度图像。探讨了之前被 相关方法所忽略的情形,该方法可以适用于任意分辨率的彩色指导图像。并且通过相关实验发现 了令人惊异的现象,即通过使用低分辨率彩色图像放大后作为指导,可以得到与使用高分辨率彩 色指导图像相近甚至更好的结果,对相关问题的研究和应用具有一定参考意义。     

基于支持向量机的多特征彩色图像边缘检测

针对在特殊领域中彩色图像边缘检测,不仅需要准确地检测到目标边缘而且需要去除非目标边缘,提出了一种新的支持向量机多特征彩色图像边缘检测方法.这种方法根据彩色图像边缘的特点,在图像亮度和色度通道上结合像素加权梯度值和像素邻域相关信息构建多维特征向量,通过训练的支持向量机可以准确识别出目标边缘.实验结果表明,该方法比传统边缘检测方法具有更好目标边缘识别能力.     

基于Curvelet的彩色癌细胞分割新方法

针对彩色图像分割问题,将Curvelet变换与SVM理论相结合,形成了有效的彩色图像分割新方法.通过曲波变换将彩色图像分解到各通道,用Mean Shift找到各通道上特征图像的模式点,再用模式点周围的样本训练SVM,用训练好的SVM对各通道样本进行精确分类,把所有通道滤波后的图像进行重构,使癌细胞凸显并二值化.该方法可以快速,精确地定位到多目标物边界.通过MATLAB进行仿真实验,表明了该方法的有效性.     

运用视频监控技术检测高速运动目标的新算法

提出了一种新的基于图像块和HVS彩色图像差值技术的高速运动目标检测算法。对分块后的图像进行粗检，辅以经验知识确定出目标的大概区域。在锁定的局部区域内运用HVS彩色图像差值方法检测出运动目标。实验结果表明，该算法克服了传统的差图像法的缺点，能够有效地抑制阴影的影响，具有自适应性强、速度快等优点。在复杂的环境下，运用该算法提取运动目标可以获得满意的效果。     

一种基于目标区域的图像检索方法

为了弥补颜色直方图等全局特征在描述彩色图像空间信息上的不足,该文提出了一种基于目标区域的彩色图像检索方法。该方法首先利用一种基于颜色视觉一致性的图像分割方法提取出有意义的目标区域,然后分别对各个区域提取HSV彩色直方图和Hu不变矩作为目标区域的特征描述,最后提出了一种相应的计算相似度的方法,实现了图像之间的相似度度量。通过在中科院计算所的Mires图像数据库和ViViLab测试图像库上进行实验,该文提出的方法对于目标明确、背景不太复杂的图像可以达到较好的检索效果。     

一种雷达目标的动态雷达散射截面模拟

为了能够掌握动态目标的飞行特性,提出了一种模拟目标动态雷达散射截面(RCS)的方法。该方法根据雷达目标航迹相关数据,结合测量坐标系和目标坐标系转换原理,采用多层快速多极子算法,仿真建立了目标静态下的RCS数据库。同时,通过编程实现了目标动态RCS模拟程序,并通过分析得到动态目标RCS曲线。该结果表明,雷达目标的动态RCS模拟对掌握目标的飞行特性起到了一定的作用。该方法可以代替RCS实际测量过程,具有实现简单、操作性好等优点。     

基于平面模板的机器人双目标定与目标定位

视觉是机器人获取外界信息最主要的途径,通过视觉系统准确地定位目标物体是机器人控制中的关键技术。为了使机器人准确地获取目标物体的位置,文中采用平面模板法对双目摄像头进行标定,构建机器人坐标系,完成对目标物体的定位。经过标定,双目摄像头可以获取目标物体在空间坐标系中的位置,经过坐标系转换,可以获得目标物体在机器人世界坐标系中的坐标值,该值是机器人实现对目标物体伺服跟踪和抓取的重要数据。最后,本方法在家庭机器人上得到了验证,机器人能够准确地定位目标物体。     

基于云模型的彩色图像分割方法

以云模型理论为基础分析彩色图像分割概念,研究已有的彩色图像分割方法,并与云模型相结合,提出基于云模型的彩色图像分割方法。该方法在HSV颜色空间对彩色图像进行非均匀量化,并寻找量化后图像的基本直方图,最后通过云模型的“3En规则”对图像进行前景/背景分割。通过与K均值算法、IS-RSC算法进行比较,实验结果表明了该方法对彩色图像分割的有效性。     

基于云模型的彩色图像分割方法

以云模型理论为基础分析彩色图像分割概念,研究已有的彩色图像分割方法,并与云模型相结合,提出基于云模型的彩色图像分割方法。该方法在HSV颜色空间对彩色图像进行非均匀量化,并寻找量化后图像的基本直方图,最后通过云模型的"3En规则"对图像进行前景/背景分割。通过与K均值算法、IS-RSC算法进行比较,实验结果表明了该方法对彩色图像分割的有效性。     

一种基于HSI的距离联合RGB 3维场边缘探测方法

在彩色图像边缘检测中，欧氏距离方法虽对亮度变化敏感，但对色度和饱和度的差异不太敏感，而矢量角方法又仅能探测色彩差异。为了在RGB3维彩色场中获取精确的边缘信息，提出了一种基于HIS(色度、饱和度和亮度)的距离联合边缘检测方法。该方法在高亮和色差大的区域主要利用矢量角对色彩差异来进行检测，而在低亮和色差小的区域则主要利用欧氏距离的亮度差异来进行边缘检测。实验表明，该方法可有效地解决矢量角存在的问题，其与LUV欧氏距离检测方法相比，则可以避免复杂的色彩空间变换计算，其检测效果也更佳。     

一种利用附加纹理信息进行三维喷绘的方法

针对三维透视投影视图中对三维物体表面纹理直接进行喷绘,以获得复杂纹理图这一计算机图形交互技术这一新问题,研究了一种将纹理图的象素位置信息转换成彩色信息,然后利用纹理映射将纹理坐标连同该点上的颜色值一起传递到与屏幕象素对应的可见点上的方法,其中颜色值依该点处的入射光线方向和表面法向被进一步转换为光强值,而纹理坐标则被解码后还原成与该可见点对应的纹理坐标,被存入信息缓冲器中,供以后使用,通过解码,可根据屏幕点直接得到纹理象素点的坐标,经过算法优化,实现了对三维物体表面纹理的实时喷绘;同时阐述了在三维图象生成技术中使用附加纹理信息的应用实例以及相关定义。     

Ground object recognition and segmentation from aerial image‐based 3D point cloud

Several attempts have been made to grasp three‐dimensional (3D) ground shape from a 3D point cloud generated by aerial vehicles, which help fast situation recognition. However, identifying such objects on the ground from a 3D point cloud, which consists of 3D coordinates and color information, is not straightforward due to the gap between the low‐level point information (coordinates and colors) and high‐level context information (objects). In this paper, we propose a ground object recognition and segmentation method from a geo‐referenced point cloud. Basically, we rely on some existing tools to generate such a point cloud from aerial images, and our method tries to give semantics to each set of clustered points. In our method, firstly, such points that correspond to the ground surface are removed using the elevation data from the Geographical Survey Institute. Next, we apply an interpoint distance‐based clustering and color‐based clustering. Then, such clusters that share some regions are merged to correctly identify a cluster that corresponds to a single object. We have evaluated our method in several experiments in real fields. We have confirmed that our method can remove the ground surface within 20 cm error and can recognize most of the objects.     

Mathematical Morphology on the Spherical CIELab Quantale with an Application in Color Image Boundary Detection

Mathematical morphology is a theory with applications in image processing and analysis. This paper presents a quantale-based approach to color morphology based on the CIELab color space in spherical coordinates. The novel morphological operations take into account the perceptual difference between color elements by using a distance-based ordering scheme. Furthermore, the novel approach allows for the use of non-flat structuring elements. An illustrative example reveals that non-flat dilations and erosions may preserve more features of a color image than their corresponding flat operations. Furthermore, the novel non-flat morphological operators yielded promising results on experiments concerning the detection of the boundaries of objects on color images.     

Visibility of road hazards in thermal, visible, and sensor-fused night-time imagery

Sensor fusion combines the output of multiple imaging sensors within a single composite display. Ideally, a fused image will retain important spatial information provided by individual input images, and will convey useful spatial or chromatic emergent information derived from the contrast between input images. The present experiment assessed the potential benefits of sensor fusion as a method of enhancing drivers' night-time detection of road hazards. Observers were asked to detect a pedestrian within thermal and visible images of a night-time scene, and within chromatic and achromatic renderings created by sensor fusion of grayscale thermal and visible images. Results indicated that fusion can both improve spatial image content, and can effectively embellish spatial content with emergent chromatic information. The benefits of both sensor fusion and of color rendering, however, were inconsistent, varying substantially with quality of input images submitted for fusion.     

基于颜色-空间特征的图像检索

虽然基于颜色直方图特征的图像检索方法简单、高效,但却丢失了颜色的空间分布信息.提出了一种基于颜色-空间特征的图像检索方法.该方法将图像内容看成由若干对象组成的集合,首先利用图像分割得到主要对象,然后根据对象的颜色、位置和形状特征计算图像间内容的相似度,再进行检索.实验结果表明,当图像中有明显的物体时,该方法与颜色直方图相比,能够更加准确和高效地查找出用户所需内容的图像,明显地提高了检索精度.     

Surface Reconstruction and Display from Range and Color Data

This paper addresses the problem of scanning both the color and geometry of real objects and displaying realistic images of the scanned objects from arbitrary viewpoints. We describe a complete system that uses a stereo camera setup with active lighting to scan the object surface geometry and color. Scans expressed in sensor coordinates are registered into a single object-centered coordinate system by aligning both the color and geometry where the scans overlap. The range data are integrated into a surface model using a robust hierarchical space carving method. The fit of the resulting approximate mesh to data is improved and the mesh structure is simplified using mesh optimization methods. In addition, a method for view-dependent texturing of the reconstructed surfaces is described. The method projects the color data from the input images onto the surface model and blends the various images depending on the location of the viewpoint and other factors such as surface orientation.     

Color Image Watermarking Using Multidimensional Fourier Transforms

This paper presents two vector watermarking schemes that are based on the use of complex and quaternion Fourier transforms and demonstrates, for the first time, how to embed watermarks into the frequency domain that is consistent with our human visual system. Watermark casting is performed by estimating the just-noticeable distortion of the images, to ensure watermark invisibility. The first method encodes the chromatic content of a color image into the CIE chromaticity coordinates while the achromatic content is encoded as CIE tristimulus value. Color watermarks (yellow and blue) are embedded in the frequency domain of the chromatic channels by using the spatiochromatic discrete Fourier transform. It first encodes and as complex values, followed by a single discrete Fourier transform. The most interesting characteristic of the scheme is the possibility of performing watermarking in the frequency domain of chromatic components. The second method encodes the components of color images and watermarks are embedded as vectors in the frequency domain of the channels by using the quaternion Fourier transform. Robustness is achieved by embedding a watermark in the coefficient with positive frequency, which spreads it to all color components in the spatial domain and invisibility is satisfied by modifying the coefficient with negative frequency, such that the combined effects of the two are insensitive to human eyes. Experimental results demonstrate that the two proposed algorithms perform better than two existing algorithms - ac- and discrete cosine transform-based schemes.     

彩色图像非参数变换立体匹配研究

将非参数Rank变换引用到彩色图像的立体配算法中,采用绝对值指数方法来计算像素的颜色相似性,对彩色图像进行一种分等级的改进Rank变换,将彩色图像转变了一个整数矩阵,然后建立一种新的匹配测度,同时加入色差梯度约束进行匹配。通过对比实验,表明这种新的匹配基元进行匹配,与直接采用灰度特征作为匹配基元的算法相比,有更好的抗噪性和匹配准确性。     

Attentional filtering in the design of electronic map displays: a comparison of color coding,intensity coding,and decluttering techniques

In a series of experiments color coding, intensity coding, and decluttering were compared in order to assess their potential benefits for accessing information from electronic map displays. Participants viewed electronic battlefield maps containing 5 classes of information discriminable by color or intensity, or, in the decluttering condition, displayed or removed entirely by a key press. Participants were asked questions requiring them to focus on objects within a class (objects presented at the same color or intensity) or to integrate data between objects in different classes (objects presented at different colors and intensities). The results suggested that the benefits of color and intensity coding appear to be in segregating the visual field rather than calling attention to the objects presented at a certain color or intensity. Interactivity proved to be a disadvantage; the time cost of information retrieval outweighed the time benefits of presenting less information on the display or even allowing map users to customize their displays. Potential applications of this research include a cost-benefit analysis for the use of 3 attentional filtering techniques and an attempt to quantitatively measure map complexity.