基于残差谱显著性区域提取的极化SAR船只检测

极化合成孔径雷达（synthetic aperture radar,SAR）包含了丰富的目标散射信息,已被广泛用于海上船只检测.文中将机器视觉中基于残差谱视觉显著性区域提取方法扩展到极化SAR船只检测.首先,全面分析SAR极化特征的船海区分能力,利用5景RADARSAT-2全极化数据,对比45种极化特征的船海欧式距离、巴氏距离和对比度,筛选出16个船海对比度大于20 dB的极化特征;其次,挑选出适用于残差谱显著性区域提取船只检测的极化特征组合,通过特征间互信息、图像对数谱特性分析,确定利用相干矩阵的三个幅度极化特征组合成RGB图像进行船只检测;最后,将本文方法与基于恒虚警率的方法比较.在测试图像中,传统方法的品质因数小于0.9,本文方法的品质因数为0.95.本文方法能够很好地抑制虚警,同时还可直接提取出目标的轮廓等几何信息,具有一定的应用前景.     

Ship detection in optical remote sensing image based on visual saliency and AdaBoost classifier

efficiency switch and modulation.     

改进的Hough与梯度直方图的人眼定位算法

针对民用航空器飞行中,实时监控机组座舱行为的疲劳检测系统的快速、精确、低计算量的需求,提出了一种基于Hough、梯度直方图结合的算法：利用Adaboost算法检测人脸之后,运用Hough变换进行人眼初检测,再利用提出的简化梯度直方图特征进行人眼的精确定位。算法将目标区域的简化梯度直方图特征送入SVM分类器,对Hough检测后存在的多个＆quot;可能圆＆quot;进行筛选,剔除Hough检测中的非人眼圆。实验对比结果表明,改进的人眼定位结合算法能够快速的检测人眼,同时粗定位缩小了Hough圆检测的范围,减小了计算量,缩短了算法运行时间,SVM和改进的梯度信息提高了定位的准确率,并且检测结果稳定、鲁棒性好。     

Non-texture image inpainting using histogram of oriented gradients

This paper presents a novel and efficient algorithm for non-texture inpainting of images based on using the dominant orientation of local gradients. It first introduces the concept of a new matrix called orientation matrix and then uses it for faster and better inpainting. The process of propagating information is carried out by using a new formulation which leads to much more efficient computations than the previous methods. The gain is both in terms of computational complexity and visual quality. The promising results in contexts of text, scratch, and block loss inpainting demonstrate the effectiveness of the proposed method.     

基于最简视觉显著性的红外目标快速提取方法

在红外深空目标跟踪系统中,为了能够从深空红外图像中快速提取微小目标,通过分析红外深空图像的特点,提出一种基于最简视觉显著性的红外目标快速提取方法。该方法在传统的视觉显著性的基础上,通过计算局部灰度最大值和目标像素的灰度平均值与邻域像素的灰度加权值的对比度组成特征向量,构造显著性模型,抑制背景并凸显目标,使之不但能够减少运算耗时,而且能够保证提取精度。通过对红外深空图像进行处理,实验结果表明该算法的运算时间仅为传统的视觉显著性算法的28%,且有较好的处理结果,证明了该算法的有效性。     

基于显著性与稠密光流的红外船只烟幕检测方法研究

船只目标是海上的一种重要目标。红外成像系统由于其可白天、夜间同时工作的特点已被广泛应用于船只检测系统中。但是,红外成像系统容易受到烟幕干扰,导致船只检测系统失效。因此及时有效地检测到红外船只图像中的烟幕干扰区域,对于提高船只目标检测系统的准确性具有重要意义。针对红外图像中船只释放的烟幕区域的检测问题,提出了一种基于显著性与稠密光流融合的烟幕检测方法。由于舰船释放的烟幕有明显区别于背景的特性,因此首先采用多尺度邻域滤波的AC算法对图像进行显著性区域检测,提取显著的烟幕区域;然后利用烟幕扩散的运动特点,对图像前后帧进行稠密光流计算得到图像的运动信息,通过设置阈值筛选得到明显的运动点、扩充运动点区域、合并分裂的运动区域,得到运动的烟幕区域;最后对显著性区域与运动烟幕区域进行合并得到最终的烟幕区域。实验结果表明,该方法能有效检测到烟幕区域,并且能够很好地适应烟幕反射光以及背景亮度的变化。     

基于视觉显著性和目标置信度的红外车辆检测技术

提出了一种复杂地面背景下的红外车辆检测算法。首先,提出一种新的自适应分段线性灰度拉伸方法来增强当图像整体亮度偏低时的目标信息。其次,利用拉伸后图像的显著性图生成目标潜在的兴趣区。再次,利用平均梯度法在兴趣区内进行目标的边缘再分割,完成目标精确分割检测。最后,利用车辆的红外融合特征计算目标置信度,对目标进行评估和确认。实验结果表明:对实际拍摄的红外图像进行检测的算法可有效地检测出地面车辆目标。     

A novel fast intra algorithm for VVC based on histogram of oriented gradient

The latest Versatile Video Coding (VVC) standard incorporates a series of effective and complex new intra coding tools, which obtains superior coding efficiency than the High Efficiency Video Coding (HEVC). However, this makes the intra coding more complicated and time-consuming. A fast algorithm for VVC from two aspects of fast mode decision and fast partition decision is proposed in this paper. For the fast mode decision, the relationship between bins with Histogram of Oriented Gradient (HOG) and intra modes is created for the mode selection, decreasing the planar modes for SATD and RDO. Moreover, we analyze the maximum bins to determine the final modes, and we use the modes of left and upper blocks as a reference for the current CU, which can early terminate RDO. Moreover, a two-step fast partition algorithm is proposed based on HOG for fast partition decision, in which two thresholds are investigated to control the uniformity of textures. The proposed fast algorithm is implemented on the VVC test model, and the experimental results show that it can achieve 69.07% time savings with only 2.96% BDBR increases averagely, which outperforms other relatively existing state-of-the-art methods. Moreover, to convince the universality of our algorithm, we further implement our method in Fraunhofer Versatile Video Encoder (VVenc) and Fraunhofer Versatile Video Decoder (VVdec), which have five settings to control the trade-off between encoding quality and efficiency for intra coding. The fast intra mode decision algorithm and fast partition algorithm decrease the complexity of intra coding for both VTM and VVenc, which shows the efficiency and universality of the proposed fast partition and fast mode decision algorithms.     

IR saliency detection via a GCF-SB visual attention framework

Infrared (IR) saliency detection with high detection accuracy is a challenging task due to the complex background and low contrast of IR images. In this paper, an IR saliency detection method via a new visual attention framework is proposed, which comprises two phases. In the first phase, a Gray & Contrast Features (GCF) model is established, in which the IR image is processed in two feature channels, a gray feature channel and a contrast feature channel. And then a primary feature map can be obtained by fusing the gray and contrast features from these two channels, which is the basis of the second phase. In the second phase, a Similarity-based Bayes (SB) model is established, in which two prior probabilities and two likelihood functions are calculated according to the previously obtained primary feature map. Finally, the saliency map is calculated with the obtained prior probabilities and likelihood functions by Bayes formula. Experimental results indicate that the proposed method can effectively reduce noise and enhance contrast of IR images with complex background and low contrast, and obtain a higher detection accuracy and robustness than seven state-of-the-art methods.     

基于视觉显著性的飞机蒙皮缺陷检测方法

飞机蒙皮缺陷是导致航空安全事故的重要因素之一.针对当前蒙皮缺陷依赖人工目视检测,存在效率低、实时性差、人工经验敏感等问题,提出一种基于局部对比度的显著性模型缺陷检测方法.算法采用 自动γ校正算法对输入缺陷图像进行修正,增强缺陷与背景的动态范围;在基于局部对比度的显著性检测模型中融入HSI颜色空间中的I分量以提升缺陷的显...     

基于方向梯度直方图和局部对比度特征的海面背景红外图像分类

在复杂多变的海面环境下,应用红外成像技术对海面中小目标进行搜救时,为有利于后续针对不同场景的目标处理,有必要对采集的原始图像进行分类处理。根据不同的环境条件,将海面红外图像分为五类场景。从两个方面对训练集图像进行特征提取,一个是通过高斯滤波将图像分为基础层和细节层,然后使用改进的方向梯度直方图（HOG）方法提取特征;另一个是提取图像的局部对比度得到局部特征。将提取的特征向量融合并输入到分类器中,使用支持向量机（SVM）对测试集图像进行分类。文章使用了HOG和局部对比度方法（LCM）结合的新特征描述符对海面红外图像的场景进行分类,与其它方法相比,结果表明改进方法的准确率达到96.4%,体现了可行性和有效性。     

Moving object extraction based on saliency detection and adaptive background model

For the ghost in visual background extractor(Vi Be)algorithm and the influence of dynamic background,an improved Vi Be algorithm is proposed to extract moving object in this paper.The way of background acquisition during modeling is improved to eliminate the ghost.Detect the saliency of the pre-M-frame,and synthetic relatively real background.Modeling with the background can avoid the generation of ghost.The selection of thresholds in the model is improved to reduce the impact of the dynamic background.Adjust the thresholds adaptively according to the background complexity.In addition,find the inner contour of extracted object to fill,which makes the detected targets more complete.Experimental results show that the presented algorithm effectively removes ghosts and enhances anti-interference ability.Compared with several existing methods,the presented algorithm has better performance.     

基于金字塔梯度方向图像特征的检索模型设计

随着互联网的普及和发展,电子商务网站数量急剧增长,迫切需要一个平台对在线销售商品进行标注以方便用户进行搜索。通过提取类别图像和测试图像的金字塔梯度方向直方图(PHOG)全部特征,然后计算两者之间的距离,测试图像与类别图像距离比较近的就属于同一类图像。利用Matlab语言开发出了能够实现这一检索分类模型。实验证明这一模型灵活性好,准确性高。     

结合视觉显著性引导与分类器融合的遥感目标检测

利用有限计算资源对大视场遥感图像进行快速目标检测有着重要的现实意义。借鉴注意机制在人类视觉系统中的选择性感知特点,结合自底向上的视觉显著性引导及自顶向下的显著区域解译,提出一种新的大视场遥感目标检测模型。设计其整体架构分为注意初期、注视阶段及注意后期3个递进的层级,通过引入一种自适应形态学的显著图生成策略快速搜寻整个视场中的显著区域,并在其引导下利用分类器融合技术从特征属性相似的显著物中区分出任务目标。以大视场遥感图像舰船检测验证模型,性能及对比实验结果表明该模型是可行的,同时实现了计算资源有层次、有重点地合理分配。     

Visual saliency detection using iterative outlier cluster elimination

Multidimensional Systems and Signal Processing - In saliency region detection, a contrast feature has been widely employed as a standard feature; however, many technical challenges remain when...     

基于显著图和稳定区域融合的小目标检测算法

在真实场景中,物体的尺寸往往是多样的,基于大 图像的目标检测很难检测所有的物体。为了检测较小尺寸目标,本文利用显著图和稳定区域 融合,建立小目标检测算法模型。首先利用基于颜色名空间的显著性检测算法生成显著图, 同时采用基于最大稳定极值区域(MSER)算法提取局部稳定区域,MSER算法是目前针对图像 变形最为稳定的特征检测算法;其次采用像素乘性融合稳定区域和显著图以降低虚警概率; 最后调用一些图像处理过程,包括形态学重建操作、灰度变换、形态空穴填充操作,能够有 效抑制背景,同时均匀的突出显著性目标,以推断和优化最终结果。为了验证该算法的有效 性和实用性,以PR曲线为评价指标,比较了几种主流算法的性能,包括AZ-NET、FPN、PGAN 。通过对Sky数据集和Ground数据集的测试,表明该算法能够很好地适应目标尺寸的变化, 在检准率和检全率方面优于现有的小目标检测算法,具有良好的鲁棒性。     

基于梯度方向直方图的干枯植物与裸土偏振光谱识别研究

从地物光谱图像识别的关键问题出发,将改进的梯度方向直方图(光谱梯度方向直方图)与"光谱总反射率"应用到偏振光谱识别研究中,实现了对5种干枯植物与3种裸土的识别.在研究中,先联合光谱梯度方向直方图特征向量的模与光谱总反射率进行层次聚类分析,可以识别6种研究对象,再单独利用光谱梯度方向直方图特征的模进行层次聚类分析识别其余2种研究对象,从而可以实现全部研究对象偏振光谱识别.     

Illumination compensation using oriented local histogram equalization and its application to face recognition

Illumination compensation and normalization play a crucial role in face recognition. The existing algorithms either compensated low-frequency illumination, or captured high-frequency edges. However, the orientations of edges were not well exploited. In this paper, we propose the orientated local histogram equalization (OLHE) in brief, which compensates illumination while encoding rich information on the edge orientations. We claim that edge orientation is useful for face recognition. Three OLHE feature combination schemes were proposed for face recognition: 1) encoded most edge orientations; 2) more compact with good edge-preserving capability; and 3) performed exceptionally well when extreme lighting conditions occurred. The proposed algorithm yielded state-of-the-art performance on AR, CMU PIE, and extended Yale B using standard protocols. We further evaluated the average performance of the proposed algorithm when the images lighted differently were observed, and the proposed algorithm yielded the promising results.     

基于视觉显著模型的遥感图像舰船快速检测

为了降低传统高分辨率海面遥感图像舰船目标检测方法的计算复杂度,提高检测速度,在舰船目标检测中引入了基于直方图对比度的视觉显著模型和空间降维算法,提出一种新的高分辨率海面遥感图像舰船目标快速检测算法。首先对高分辨率遥感图像进行空间降维,然后计算降维图的视觉显著图,突出感兴趣目标区域,最后利用最大类间方差法分割视觉显著图以获取舰船目标候选区域。结果表明,目标检测所消耗的时间减小为原来的10%~12%,弱化了复杂海面纹理背景对目标检测的影响。该研究提高了高分辨率遥感图像舰船目标的检测效率。