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1.
手写数字串的分割与字符识别密切相关.采用基于识别的分割方法,在分割过程中引入识别机制识别分割碎片,将识别结果经过差值运算后置为每个识别对象的识别可信度,利用动态规划找到最佳分割路径.在训练分类器时,使用反例样本估计分类器参数,得到了性能良好的分类器.实验数据表明,利用正例和反例样本结合训练的分类器比只经过正例样本训练的分类器的识别率要高很多.  相似文献   

2.
Automatic segmentation of images is a very challenging fundamental task in computer vision and one of the most crucial steps toward image understanding. In this paper, we present a color image segmentation using automatic pixel classification with support vector machine (SVM). First, the pixel-level color feature is extracted in consideration of human visual sensitivity for color pattern variations, and the image pixel's texture feature is represented via steerable filter. Both the pixel-level color feature and texture feature are used as input of SVM model (classifier). Then, the SVM model (classifier) is trained by using fuzzy c-means clustering (FCM) with the extracted pixel-level features. Finally, the color image is segmented with the trained SVM model (classifier). This image segmentation not only can fully take advantage of the local information of color image, but also the ability of SVM classifier. Experimental evidence shows that the proposed method has a very effective segmentation results and computational behavior, and decreases the time and increases the quality of color image segmentation in compare with the state-of-the-art segmentation methods recently proposed in the literature.  相似文献   

3.
We propose an approach to image segmentation that views it as one of pixel classification using simple features defined over the local neighborhood. We use a support vector machine for pixel classification, making the approach automatically adaptable to a large number of image segmentation applications. Since our approach utilizes only local information for classification, both training and application of the image segmentor can be done on a distributed computing platform. This makes our approach scalable to larger images than the ones tested. This article describes the methodology in detail and tests it efficacy against 5 other comparable segmentation methods on 2 well‐known image segmentation databases. Hence, we present the results together with the analysis that support the following conclusions: (i) the approach is as effective, and often better than its studied competitors; (ii) the approach suffers from very little overfitting and hence generalizes well to unseen images; (iii) the trained image segmentation program can be run on a distributed computing environment, resulting in linear scalability characteristics. The overall message of this paper is that using a strong classifier with simple pixel‐centered features gives as good or better segmentation results than some sophisticated competitors and does so in a computationally scalable fashion.  相似文献   

4.
Image segmentation partitions an image into nonoverlapping regions, which ideally should be meaningful for a certain purpose. Thus, image segmentation plays an important role in many multimedia applications. In recent years, many image segmentation algorithms have been developed, but they are often very complex and some undesired results occur frequently. By combination of Fuzzy Support Vector Machine (FSVM) and Fuzzy C-Means (FCM), a color texture segmentation based on image pixel classification is proposed in this paper. Specifically, we first extract the pixel-level color feature and texture feature of the image via the local spatial similarity measure model and localized Fourier transform, which is used as input of FSVM model (classifier). We then train the FSVM model (classifier) by using FCM with the extracted pixel-level features. Color image segmentation can be then performed through the trained FSVM model (classifier). Compared with three other segmentation algorithms, the results show that the proposed algorithm is more effective in color image segmentation.  相似文献   

5.
基于训练样本自动选取的SVM彩色图像分割方法   总被引:1,自引:0,他引:1  
张荣  王文剑  白雪飞 《计算机科学》2012,39(11):267-271
图像分割是模式识别、图像理解、计算机视觉等领域的重要研究内容。基于支持向量机((Support Vcctor Ma- chine, SVM)的方法现已广泛应用于图像分割,但其在训练样本的选取上大多是人工选择,这降低了图像分割的自适 应性,且影响了SVM的分类性能。提出一种基于训练样本自动选取的SVM彩色图像分割方法,算法首先使用模糊 C均值(Fuzzy C-Mcans, FCM)聚类算法自动获取训练样本,然后分别提取图像颜色特征和纹理特征,将其作为SVM 模型训练样本的特征属性进行训练,最后用训练好的分类器对图像进行分割。实验结果表明,提出的方法可取得很好 的分割结果。  相似文献   

6.
7.
基于Ncut分割和SVM分类器的医学图像分类算法   总被引:2,自引:0,他引:2  
为解决医疗诊断中由于疲劳和主观因素影响导致的诊断错误,本文提出了基于Ncut分割方法的医学CT图像的分割、特征提取和诊断的新方案.将Ncut分割方法应用于脑CT图像.先进行图像分割,提取感兴趣区域,再从边缘、灰度,纹理三方面提取特征,最后利用支持向量机(SVM)对图像进行分类,为医生的诊断提供参考.从表格化的分类结果看,所提方案有较大的应用价值.  相似文献   

8.
This paper addresses the problem of automatically extracting perceptive information from acoustic signals, in a supervised classification context. Global labels, i.e., atomic information describing a music title in its entirety, such as its genre, mood, main instruments, or type of vocals, are entered by humans. Classifiers are trained to map audio features to these labels. However, the performances of these classifiers on individual labels are rarely satisfactory. In the case we have to predict several labels simultaneously, we introduce a correction scheme to improve these performances. In this scheme-an instance of the classifier fusion paradigm-an extra layer of classifiers is built to exploit redundancies between labels and correct some of the errors coming from the individual acoustic classifiers. We describe a series of experiments aiming at validating this approach on a large-scale database of music and metadata (about 30 000 titles and 600 labels per title). The experiments show that the approach brings statistically significant improvements.  相似文献   

9.
This paper proposes a sliding window approach, whose length and time shift are dynamically adaptable in order to improve model confidence, speed and segmentation accuracy in human action sequences. Activity recognition is the process of inferring an action class from a set of observations acquired by sensors. We address the temporal segmentation problem of body part trajectories in Cartesian Space in which features are generated using Discrete Fast Fourier Transform (DFFT) and Power Spectrum (PS). We pose this as an entropy minimization problem. Using entropy from the classifier output as a feedback parameter, we continuously adjust the two key parameters in a sliding window approach, to maximize the model confidence at every step. The proposed classifier is a Dynamic Bayesian Network (DBN) model where classes are estimated using Bayesian inference. We compare our approach with our previously developed fixed window method. Experiments show that our method accurately recognizes and segments activities, with improved model confidence and faster convergence times, exhibiting anticipatory capabilities. Our work demonstrates that entropy feedback mitigates variability problems, and our method is applicable in research areas where action segmentation and classification is used. A working demo source code is provided online for academical dissemination purposes, by requesting the authors.  相似文献   

10.
Skin detection is used in applications ranging from face detection, tracking of body parts, hand gesture analysis, to retrieval and blocking objectionable content. We present a systematic approach for robust skin segmentation using graph cuts. The skin segmentation process starts by exploiting the local skin information of detected faces. The detected faces are used as foreground seeds for calculating the foreground weights of the graph. If local skin information is not available, we opt for the universal seed. To increase the robustness, the decision tree based classifier is used to augment the universal seed weights when no local information is available in the image. With this setup, we achieve robust skin segmentation, outperforming off-line trained classifiers. The setup also provides a generic skin detection system, using positive training data only. With face detection, we take advantage of the contextual information present in the scene. With the weight augmentation, we provide a setup for merging spatial and non-spatial data. Experiments on two datasets with annotated pixel-level ground truth show that the systematic skin segmentation approach outperforms other approaches and provides robust skin detection.  相似文献   

11.
We present a machine learning tool for automatic texton-based joint classification and segmentation of mitochondria in MNT-1 cells imaged using ion-abrasion scanning electron microscopy (IA-SEM). For diagnosing signatures that may be unique to cellular states such as cancer, automatic tools with minimal user intervention need to be developed for analysis and mining of high-throughput data from these large volume data sets (typically ). Challenges for such a tool in 3D electron microscopy arise due to low contrast and signal-to-noise ratios (SNR) inherent to biological imaging. Our approach is based on block-wise classification of images into a trained list of regions. Given manually labeled images, our goal is to learn models that can localize novel instances of the regions in test datasets. Since datasets obtained using electron microscopes are intrinsically noisy, we improve the SNR of the data for automatic segmentation by implementing a 2D texture-preserving filter on each slice of the 3D dataset. We investigate texton-based region features in this work. Classification is performed by k-nearest neighbor (k-NN) classifier, support vector machines (SVMs), adaptive boosting (AdaBoost) and histogram matching using a NN classifier. In addition, we study the computational complexity vs. segmentation accuracy tradeoff of these classifiers. Segmentation results demonstrate that our approach using minimal training data performs close to semi-automatic methods using the variational level-set method and manual segmentation carried out by an experienced user. Using our method, which we show to have minimal user intervention and high classification accuracy, we investigate quantitative parameters such as volume of the cytoplasm occupied by mitochondria, differences between the surface area of inner and outer membranes and mean mitochondrial width which are quantities potentially relevant to distinguishing cancer cells from normal cells. To test the accuracy of our approach, these quantities are compared against manually computed counterparts. We also demonstrate extension of these methods to segment 3D images obtained using electron tomography.  相似文献   

12.
基于Real Adaboost的肤色分割方法   总被引:1,自引:0,他引:1  
余益民  黄廷辉  桑涛 《计算机应用》2011,31(12):3370-3372
提出了一种基于Real AdaBoost算法构造的肤色置信度分类器及动态阈值相结合的肤色分割方法。根据肤色在YCrCb色度空间的聚类性,通过大量肤色和非肤色样本用Real AdaBoost训练一族查找表(LUT)型圆形弱分类器,组成一个能输出连续置信度的强分类器,利用肤色强分类器计算图像中像素的肤色相似度,最后用大津法确定阈值对肤色相似图进行二值分割。实验表明,该方法能较好地描述肤色分布,误检率低,鲁棒性好。  相似文献   

13.
Image segmentation is an important tool in image processing and can serve as an efficient front end to sophisticated algorithms and thereby simplify subsequent processing. In this paper, we present a color image segmentation using pixel wise support vector machine (SVM) classification. Firstly, the pixel-level color feature and texture feature of the image, which is used as input of SVM model (classifier), are extracted via the local homogeneity model and Gabor filter. Then, the SVM model (classifier) is trained by using FCM with the extracted pixel-level features. Finally, the color image is segmented with the trained SVM model (classifier). This image segmentation not only can fully take advantage of the local information of color image, but also the ability of SVM classifier. Experimental evidence shows that the proposed method has a very effective segmentation results and computational behavior, and decreases the time and increases the quality of color image segmentation in comparison with the state-of-the-art segmentation methods recently proposed in the literature.  相似文献   

14.
Assembly fixtures are commonly used to locate rigid and compliant components for joining operations. Piezoelectric (PZT) impedance sensors can be used to individually monitor assembly fixtures and have been proven effective for structural health monitoring applications. The sensors rapidly record significant quantities of data, but must be bonded to a fixture in order to transmit an input signal and record the corresponding output signal. Thus, PZT impedance sensors become a permanent feature of an assembly fixture and may create unique systems defined by the assembly fixture and impedance sensor (AFIS). Previous research has shown success in detecting fixture damage using PZT impedance sensors. This paper extends previous fixture damage detection work to damage diagnosis through the use of data mining classifiers. Classifiers were used in three studies; the first was to show that classifiers can be trained to classify a healthy fixture, fixture damage, and multiple severities of fixture damage in an isolated AFIS. In the second study, classifier generalization was tested by simulating an unknown damage. Lastly, classifiers were used to study the uniqueness (i.e. fixture classification) of two AFIS, which could have implications related to the practical application of classifier models to any AFIS.  相似文献   

15.
In this study, we propose an integrated approach based on iterative sliced inverse regression (ISIR) for the segmentation of ultrasound and magnetic resonance (MR) images. The approach integrates two stages. The first is the unsupervised clustering which combines multidimensional scaling (MDS) with K-Means. The dimension reduction based on MDS is employed to obtain fewer representative variates as input variables for K-Means. This step intends to generate the initial group labels of the training data for the second stage of supervised segmentation. We then combine the SIR with the nearest mean classifier (NMC) or the support vector machine (SVM) to iteratively update the group labels for supervised segmentation. The method of SIR is introduced by Li [Sliced inverse regression for dimension reduction. J. Am. Stat. Assoc. 86 (1991) 316–342] to explore the effective dimension reduction (e.d.r.) directions from the training data embedded in high-dimensional space. The test data are then projected onto these directions and the classifiers are further applied to classify the test data. The integrated approach based on ISIR is evaluated on simulated and clinical images, which include ultrasound and MR images. The evaluation results indicate that this approach provides an improvement of image segmentation over the methods to be compared without dimension reduction.  相似文献   

16.
Color image segmentation by fixation-based active learning with ELM   总被引:1,自引:0,他引:1  
The human vision observes an image by making a series of fixations. In fixation, our eyes continually tremble, which is called the microsaccades that may reflect an optimal sampling strategy and spatiotemporal characteristics. Although the decrease in microsaccade magnitude leads to visual fading in our brain that may provide a mechanism to shift fixation. This paper proposes an iterative framework for figure-ground segmentation by sampling-learning via simulating human vision. First, fixation-based sampling is utilized to get a few positive and negative samples. A pixels classifier based on the RGB color could be trained by ELM (extreme learning machine) algorithm, which not only extracts object regions, but also provides a reference boundary of objects. Then, the boundary of object region could be refined by minimizing graph cut. The region of refined object can be re-sampled to provide more accurate samples/pixels involved object and background for the next training. The iteration would convergence when the pixel classifier gets stable segmentation result continually. Based on the ELM algorithm, the proposed method run faster than state-of-the-art method, and can cope with the complexity and uncertainty of the scene. Experimental results demonstrate the learning-based method could reliably segment multiple-color objects from complex scenes.  相似文献   

17.
In this paper the adaptive binary classifier is applied for the classification of the tensotremorogramm (TTG) time series. The idea is to reveal pathological states of human motor control system. Adaptive binary classifier being a new type of trained classifiers can be trained on the data for healthy subjects. Then the trained classifier can be used for the examinees division into healthy and sick patients. It is shown, that the trained adaptive binary classifier is able to classify the patients with acceptable accuracy. Other method of classification-Neural Clouds-has also been used. The comparison both methods has been done.  相似文献   

18.
: The performance of a multiple classifier system combining the soft outputs of k-Nearest Neighbour (k-NN) Classifiers by the product rule can be degraded by the veto effect. This phenomenon is caused by k-NN classifiers estimating the class a posteriori probabilities using the maximum likelihood method. We show that the problem can be minimised by marginalising the k-NN estimates using the Bayesian prior. A formula for the resulting moderated k-NN estimate is derived. The merits of moderation are examined on real data sets. Tests with different bagging procedures indicate that the proposed moderation method improves the performance of the multiple classifier system significantly. Received: 21 March 2001, Received in revised form: 04 September 2001, Accepted: 20 September 2001  相似文献   

19.
Motion phase plays an important role in the spatial–temporal parameters of human motion analysis. Multi-sensor fusion technology based on inertial sensors frees the monitoring of the human body phase from space constraints and improves the flexibility of the system. However, human phase segmentation methods usually rely on the determination of the positioning of the sensor and the number of sensors, it is difficult to artificially select the number and position of the sensors, especially when human motion phases are diverse. This paper proposes a selection framework for the sensor combination feature subset for motion phase segmentation, which combines feature selection algorithms with the subsequent classifiers, and determine the optimum combination of the sensor and the feature subset according to the performance of the trained model. Through the constraint and the sensor combination feature subset (SCFS), the filter method can select any number of sensors and control the size of the feature subset; the embedded method can select any number of sensors, but the size of the feature subset is determined by the classifier model. Experimental results show that the proposed framework can effectively select a specified number of sensors without human intervention, and the number of sensors has an impact on the recognition rate of the classifier within 1.5%. In addition, the filter method has good adaptability to a variety of classifiers, and the classifier prediction time can be controlled by setting the subset size of the feature; the embedded method can achieve a better phase segmentation effect than the filter method. For the application of motion phase segmentation, the proposed framework can reliably and quickly identify redundant sensors that provide effective support for reducing the complexity of the wearable sensor system and improving user comfort.  相似文献   

20.
We present InstanceFusion, a robust real-time system to detect, segment, and reconstruct instance-level 3D objects of indoor scenes with a hand-held RGBD camera. It combines the strengths of deep learning and traditional SLAM techniques to produce visually compelling 3D semantic models. The key success comes from our novel segmentation scheme and the efficient instance-level data fusion, which are both implemented on GPU. Specifically, for each incoming RGBD frame, we take the advantages of the RGBD features, the 3D point cloud, and the reconstructed model to perform instance-level segmentation. The corresponding RGBD data along with the instance ID are then fused to the surfel-based models. In order to sufficiently store and update these data, we design and implement a new data structure using the OpenGL Shading Language. Experimental results show that our method advances the state-of-the-art (SOTA) methods in instance segmentation and data fusion by a big margin. In addition, our instance segmentation improves the precision of 3D reconstruction, especially in the loop closure. InstanceFusion system runs 20.5Hz on a consumer-level GPU, which supports a number of augmented reality (AR) applications (e.g., 3D model registration, virtual interaction, AR map) and robot applications (e.g., navigation, manipulation, grasping). To facilitate future research and reproduce our system more easily, the source code, data, and the trained model are released on Github: https://github.com/Fancomi2017/InstanceFusion .  相似文献   

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