基于Gabor-PCA的人脸遮挡区域重建算法

针对遮挡人脸重建和识别问题,提出一种基于Gabor滤波和主成分分析相融合的人脸遮挡区重建算法。首先通过构建5维8方向的Gabor直方图信息分类器,从人脸库中选择Gabor直方图信息与待重建原始人脸图像在外形轮廓等粗信息更为接近的图像组成训练样本集,然后采用主成分分析对奇异值分解重建协方差矩阵进行投影形成重建图像,最后进行仿真实验。结果表明,该算法可以得到平滑自然的重建人脸图像,而且具有较强的适应性。     

基于混合能量活动轮廓模型的人脸分割方法

由于受到面部五官、饰物等因素的影响,传统几何活动轮廓模型获取人脸外轮廓会产生凹陷、分片等现象.针对人脸图像的特点,将边缘外张力能量及肤色能量与全局能量结合,提出一种基于混合能量泛函的几何活动轮廓模型,有效地避免了这些问题.首先,根据演化曲线的邻域信息赋予边缘点向外的张力,使曲线能够克服面部特征及面部饰物的干扰,引导其向外轮廓方向演化.鉴于肤色是面部最重要的特征,提出肤色能量,进一步提高了模型的鲁棒性.此外,提出一种基于单高斯模型的改进算法,能够估计出接近实际人脸外轮廓的初始位置,为轮廓演化奠定了基础.在两个公共人脸库上进行测试,该方法能够得到准确的人脸分割效果;以手工分割的结果为基准,该算法定位精度明显优于传统的全局能量模型和局部能量模型.还用日常照片创建一个包含不同姿态、光照、复杂背景等因素、复杂的人脸库,分割结果表明,该方法能够克服这些因素的影响,取得了准确而稳定的人脸分割结果.     

关键人脸轮廓区域卡通风格化生成算法

针对人脸轮廓特征区域的局部化限定,结合关键特征点的提取和脸部邻近颜色区域的融合,并引入注意力机制,提出了一种基于CycleGAN的关键人脸轮廓区域卡通风格化生成算法,以此作为初始样本构建生成对抗网络(GAN)并获取自然融合的局部卡通风格化人脸图像.利用人脸轮廓及关键特征点进行提取,结合颜色特征信息限定关键人脸风格化区域...     

高精度连续人脸轮廓提取

提取连续且高精度的人脸轮廓线是很多图像应用重要的基础步骤.然而很多现有的轮廓提取方法并不能很好地应用在人脸轮廓上.为此提出一种快速可靠的人脸轮廓提取方法,能够在关键点提供初始化后提取到高精度连续人脸轮廓线.其主要步骤是先拟合关键点形成一条初始化曲线,沿其密集采样重叠的矩形区域,将整个人脸轮廓区域划分成很多小的区域;然后在每个局部的矩形区域提取出一条抛物线引导基于梯度的局部人脸轮廓线;最后从很多局部人脸轮廓线中,通过全局融合找到最终的人脸轮廓线.这种交叉验证的机制保证了最后结果的正确性.最后在LFPW和HELEN人脸数据集上进行了实验,结果表明文中方法能有效地提高人脸轮廓提取的精度.     

基于Adaboost和最小割算法的视频人脸检测

Adaboost算法是一种被广泛应用于人脸检测的分类器学习方法,通过Haar-like特征和样本的学习和训练,形成一个强分类器,能有效地区分人脸跟非人脸.文中提出一种Adaboost结合最小割算法的人脸提取方法,该方法着眼于图像中的轮廓及肤色信息,对每个点设置一个权值,寻找一条权值最小的边界,准确提取出人脸.实验结果表明,Adaboost和最小割的人脸提取算法,分割效果较好,且耗时较小.     

基于级联支持向量机融合多特征的人脸检测

人脸图像中包含丰富的特征信息,不同特征具有其各自的优势。基于此,提出一种基于级联支持向量机有效融合多种特征的人脸检测算法。该算法首先利用肤色模型对待检图像进行预处理,筛选出疑似人脸区域。然后在疑似区域中提取图像的HOG(Histogram of Oriented Gradients)和LBP(Local Binary Patterns)特征,并分别对这两种特征集进行特征选择,训练两个SVM(Support Vector Machine)分类器,最后将两个SVM分类器级联起来实现人脸检测。在多个人脸图像数据库上的实验结果表明,该人脸检测算法提高了人脸检测率,降低了误检率,并且对多种光照条件、姿态、表情以及部分遮挡的情况都具有较好的鲁棒性。     

基于级联式Boosting方法的人脸检测

提出一种基于级联式Boosting方法的人脸检测算法。先用PCA方法对人脸图像进行特征参数的提取,在此基础上,利用算法中的每一个Boosting分类器学习的历史信息,基于线性回归特征消除（RFE）策略,消除AdaBoost中的冗余,据此判别一幅图像是否为人脸图像。在ORL人脸图像库的仿真实验结果显示,这种方法明显提高了检测性能,证明了该算法是有效的。     

基于深度学习的人脸图像加密算法研究

图像作为视觉传达的重要信息载体,以一种直观、形象的方式向受众传递信息。但是,图像会在不知不觉中带来个人隐私信息泄露等安全隐患。本文从保护图像中隐私安全角度出发,深度融合人脸检测、人脸对齐方法以及混合混沌序列的图像加解密算法,提出了一种基于深度学习算法的人脸图像信息加密算法,即FIIE（Face Image Information Encryption ）算法,用于保护图片中的面部核心部位隐私信息。FIIE算法的具体描述如下：首先,采用WLDER FACE数据集中的人脸图像对MTCNN模型展开训练,并利用训练好的模型根据人脸特征点获取图像中人脸所在的矩形框坐标;然后,通过上述人脸区域坐标生成掩膜,运用生成的掩膜使原图与Logistic混沌序列做位运算,最后,对图像中人脸特定区域的加密。通过实验表明,本算法可以准确识别图像中人脸信息特定区域,实现对图像中面部信息的有效加密,保障用户的隐私安全。     

基于Adaboost算法的多角度人脸检测

文中提出了一种基于Adaboost算法的多角度人脸检测方法.多角度人脸检测问题的研究与正面人脸检测相比,相对薄弱,离实际应用的需求还比较远.首先使用Haar特征设计并构造弱分类器空间,用Adaboost算法学习得到基于视图的多分类器级联的人脸检测器;然后将多角度人脸划分成三类:全侧脸,半侧脸及正面人脸,并为不同角度的人脸建立不同的检测器分别用于检测.在CMU侧面人脸检测集合上,用基于Adaboost的方法对多角度人脸图像进行仿真实验,检测正确率为89.8%,误报数为243个.相比Schneiderman等人的方法,该方法具有更好的性能.     

融合肤色信息和椭圆环模板的人脸检测

融合肤色信息和人脸轮廓信息,提出了一种新颖的基于肤色信息和人脸轮廓的人脸检测算法.首先利用改进的肤色提取算法对肤色进行分割,分析肤色区域,找出备选人脸;然后对备选人脸区域进行边缘检测,根据边缘检测点进行人脸轮廓特征的匹配,找出入脸的准确位置,并利用马赛克模板排除虚假人脸.实验结果表明,该算法具有较高的准确率,检测速度快...     

人脸边缘自适应搜索算法及仿真研究

人脸轮廓线提取是人脸识别中极为重要的内容,一种可靠、精确的人脸边缘提取算法对于身份鉴定技术等方面具有重要的应用价值。该文基于传统的边缘提取算法提出了一种自适应搜索轮廓线算法,首先基于人脸检测结果确定内外轮廓及搜索路径,然后对于每一条搜索路径提取出真正的轮廓点,最后利用人脸轮廓的平滑性通过曲线拟合完成轮廓线提取。该文以彩色人脸图像库数据为例,快速、准确地得到人脸轮廓线。仿真试验结果表明,该算法能在保持边缘检测精度的情况下,克服了噪声对轮廓特征提取的影响,并且对于姿势变化有一定的鲁棒性,具有一定的应用价值。     

类肤色背景中提取人脸轮廓的方法研究

提出了一个基于肤色并融合多种信息的人脸轮廓提取方法。首先在TSL色彩空间求取肤色概率图,选取种子点,然后利用多源信息进行区域生长,提取出人脸轮廓;为克服区域生长计算量大的缺点,采用了变分辨率图像金字塔策略。经实例验证,该算法能够快速准确地从类肤色背景中较好地提取出人脸轮廓,且具有较高的抗噪性和应用适应性。     

An integrated automatic face detection and recognition system

This paper proposes an integrated system for unconstrained face recognition in complex scenes. The scale and orientation tolerant system comprises a face detector followed by a recognizer. Given a color input image of a person, the face detector encloses the face from the complex scene within a circular boundary, and locates the position of the nose. A radial grid mapping centered on the nose is then performed to extract a feature vector within the boundary. The feature vector is input to a radial basis function neural network classifier for face identification. The proposed face detector achieved an average detection rate of 95.8% while the face recognizer achieved an average recognition rate of 97.5% on a database of 21 persons with variations in scale, orientation, natural illumination and background. The two modules were combined to form an automatic face recognition system that was evaluated in the context of a security system using a video database of 21 users and 10 intruders, acquired in an unconstrained environment. A recognition rate of 93.5% with 0% false acceptance rate was achieved.     

基于正面人脸图像的人脸轮廓的提取

近年来，人脸识别技术成为当前模式识别和人工智能领域的一个研究热点，人脸轮廓提取是人脸特征检测和人脸识别等人脸图像分析的重要前提，但至今仍没有得到圆满的解决。该文针对复杂背景的彩色人脸图像，提出并实现了一种人脸轮廓提取的方法。首先滤波和二值化人脸图像，在二值化图像中采用一种快速的肤色区域边界提取算法确定人脸区域;再在人脸区域内，采用轮廓跟踪技术提取出人脸轮廓。实验结果表明，该方法具有很高的精度和很强的鲁棒性。     

Real-time moustache detection by combining image decolorization and texture detection with applications to facial gender recognition

There are still many challenging problems in facial gender recognition which is mainly due to the complex variances of face appearance. Although there has been tremendous research effort to develop robust gender recognition over the past decade, none has explicitly exploited the domain knowledge of the difference in appearance between male and female. Moustache contributes substantially to the facial appearance difference between male and female and could be a good feature to be incorporated into facial gender recognition. Little work on moustache segmentation has been reported in the literature. In this paper, a novel real-time moustache detection method is proposed which combines face feature extraction, image decolorization and texture detection. Image decolorization, which converts a color image to grayscale, aims to enhance the color contrast while preserving the grayscale. On the other hand, moustache appearance is normally grayscale surrounded by the skin color face tissue. Hence, it is a fast and efficient way to segment the moustache by using the decolorization technology. In order to make the algorithm robust to the variances of illumination and head pose, an adaptive decolorization segmentation has been proposed in which both the segmentation threshold selection and the moustache region following are guided by some special regions defined by their geometric relationship with the salient facial features. Furthermore, a texture-based moustache classifier is developed to compensate the decolorization-based segmentation which could detect the darker skin or shadow around the mouth caused by the small lines or skin thicker from where he/she smiles as moustache. The face is verified as the face containing a moustache only when it satisfies: (1) a larger moustache region can be found by applying the decolorization segmentation; (2) the segmented moustache region is detected as moustache by the texture moustache detector. The experimental results on color FERET database showed that the proposed approach can achieve 89 % moustache face detection rate with 0.1 % false acceptance rate. By incorporating the moustache detector into a facial gender recognition system, the gender recognition accuracy on a large database has been improved from 91 to 93.5 %.     

基于轮廓信息的人脸检测

针对彩色图像提出了一种基于肤色模型、脸部轮廓信息以及眼睛特征的人脸检测算法。采用基于YCbCr色彩空间的肤色分割模型,初步筛选人脸的候选区域;在此基础上进行边缘检测,获得人脸轮廓信息,并利用遗传算法拟合脸部的椭圆;在椭圆的水平方向根据眼睛的几何特征来检测“眼睛对”,再根据“三停五眼”来定位人脸,并利用左右对称性验证人脸。实验表明,该算法对于彩色图像的正面人脸检测具有良好的效果。     

非均匀光照条件下的彩色人脸图像增强

针对非均匀光照彩色人脸图像增强中肤色失真问题,提出了一种基于单尺度Retinex和肤色模型的方法。将人脸图像转换至YCbCr颜色空间,并采用不同的方法分别处理Y分量和CbCr分量。针对亮度分量（Y）采用单尺度Retinex方法压缩图像的动态范围,增强图像暗处的细节信息;针对图像中肤色区域,根据肤色在CbCr空间具有聚集性的特点,调整亮度分量增强后肤色像素点色度分量（Cb和Cr）的值,改善肤色区域的颜色质量。在CAS-PEAL人脸库中进行实验,该方法与传统的人脸图像增强方法相比,在图像细节呈现能力和面部色彩真实程度方面均有提高。     

Faces detection method based on skin color modeling

This study suggests a method to improve the speed of a sliding window type of face detector by way of skin color region detection. The face detection method by way of skin color region detection has been studied in various perspectives: Complicated background images because of the area whose color is similar to the skin color cause high false positive rates. In contrast, the face detection method based on appearance, which adopts a sliding window type, may involve high face detection rates but cause tremendous computational costs in the process of detection scanning as the image size increases, whereas the processing time is also extended accordingly. This study suggests a method to control the subwindow size and detection area of a sliding window by detecting and using the skin color region with the processing time reduced. By means of a face detector with haar wavelet and LBP features, 274 images were collected online in addition to Bao database images, and then an experiment was conducted with them. As a result, the face detection time in utilization of an existing sliding window decreased down to a maximum of 47%.     

Extracting eyebrow contour and chin contour for face recognition

This paper proposes a novel method for extraction of eyebrow contour and chin contour. We first segment rough eyebrow regions using spatial constrained sub-area K-means clustering. Then eyebrow contours are extracted by Snake method with effective image force. For chin contour extraction, we first estimate several possible chin locations which are used to build a number of curves as chin contour candidates. Based on the chin like edges extracted by proposed chin edge detector, the curve with the largest likeliness to be the actual chin contour is selected. Finally, the credible extracted eyebrow contour and the estimated chin contours are used as geometric features for face recognition. Experimental results show that the proposed algorithms can extract eyebrow contours and chin contours with good accuracy and the extracted features are effective for improving face recognition rates.