几种图像分割技术的比较

本文主要介绍了图像分割的几种方法:基于阈值的分割方法、基于边缘的分割方法和基于区域的分割方法及其各自存在的问题和最新进展,同时介绍了结合特定理论工具的分割方法,最后指出了图像分割技术的发展趋势。     

全卷积神经网络图像语义分割方法综述

图像语义分割是计算机视觉领域的热点研究课题,随着全卷积神经网络的迅速兴起,图像语义分割和全卷积神经网络的融合发展取得了非常卓越的成绩.通过对近年来高质量文献的收集,重点对全卷积神经网络图像语义分割方法进行总结.将收集的文献,按照应用场景的不同,划分为经典语义分割、实时性语义分割和RGBD语义分割,对具有代表性的分割方法...     

A syntactic method for image segmentation and object recognition

In this paper, image segmentation and object recognition using syntactic methods are investigated. The segmentation process is embedded in the parsing algorithm. The approach can be described by a syntax-directed relaxation process. Previous error-correcting parsing algorithms, however, have not tackled the segmentation problem satisfactorily. Experimental results using Synthetic Aperture Radar (SAR) images are given.     

Granulation,rough entropy and spatiotemporal moving object detection

A new spatio-temporal segmentation approach for moving object(s) detection and tracking from a video sequence is described. Spatial segmentation is carried out using rough entropy maximization, where we use the quad-tree decomposition, resulting in unequal image granulation which is closer to natural granulation. A three point estimation based on Beta Distribution is formulated for background estimation during temporal segmentation. Reconstruction and tracking of the object in the target frame is performed after combining the two segmentation outputs using its color and shift information. The algorithm is more robust to noise and gradual illumination change, because their presence is less likely to affect both its spatial and temporal segments inside the search window. The proposed methods for spatial and temporal segmentation are seen to be superior to several related methods. The accuracy of reconstruction has been significantly high.     

基于卷积神经网络的脑肿瘤分割方法综述

脑肿瘤自动分割对脑肿瘤诊断、手术规划和治疗评估中起着重要的作用。然而,由于脑病变结构的高可变性,组织边界模糊,以及数据有限和类不平衡等问题,导致其仍面临巨大的挑战。目前,大部分分割依赖手工,耗时耗力,易受主观影响,寻求一种高效的自动分割方法非常具有研究意义。介绍了脑肿瘤分割的研究背景、意义和难点,并概述了其发展历程;从数据和结构优化两方面详细描述基于脑肿瘤分割的卷积神经网络,简介脑分割常用的数据集和性能指标;分析了2017至2019年的BraTs挑战赛中排名靠前的算法性能,并讨论分析卷积神经网络应用于脑肿瘤分割的发展趋势。     

Image structure representation and processing: a discussion of some segmentation methods in cytology

Image processing methods (segmentation) are presented in connection with a modeling of image structure. An image is represented as a set of primitives, characterized by their type, abstraction level, and a list of attributes. Entities (regions for example) are then described as a subset of primitives obeying particular rules. Image segmentation methods are discussed, according to the associated image modeling level. Their potential efficacity is compared, when applied to cytologic image analysis.     

MRI脑肿瘤图像分割研究进展及挑战

脑肿瘤分割是医学图像处理中的一项重要内容,其目的是辅助医生做出准确的诊断和治疗,在临床脑部医学领域具有重要的实用价值。核磁共振成像（MRI）是临床医生研究脑部组织结构的主要影像学工具,为了使更多研究者对MRI脑肿瘤图像分割理论及其发展进行探索,本文对该领域研究现状进行综述。首先总结了用于MRI脑肿瘤图像分割的方法,并对现有方法进行了分类,即分为监督分割和非监督分割;然后重点综述了基于深度学习的脑肿瘤分割方法,在研究其关键技术基础上归纳了优化策略;最后介绍了脑肿瘤分割（BraTS）挑战,并结合挑战中所用方法展望了脑肿瘤分割领域未来的发展趋势。MRI脑肿瘤图像分割领域的研究已经取得了一些显著进展,尤其是深度学习的发展为该领域的研究提供了新的思路。但由于脑肿瘤在大小、形状和位置方面的高度变化,以及脑肿瘤图像数据有限且类别不平衡等问题,使得脑肿瘤图像分割仍是一个极具挑战的课题。由于分割过程缺乏可解释性和透明性,如何将全自动分割方法应用于临床试验,还需要进行深入研究。     

Segmentation of a seismic section using image processing and artificial intelligence techniques

Methods for segmenting stacked seismic data into zones of common signal character based on texture analysis are described. Their performance is demonstrated on a line of seismic data from the Gulf of Mexico that had been manually segmented. Two segmentation methods are described. The first is a template matching scheme that matches previously selected data templates with a block of pixels. The second uses statistics determined by examining the run-length of seismic reflection events. The run-length method is extended, through a decision process called the RESOLVER, to incorporate heuristic rules to influence the segmentation. A comparison is made between the automatic segmentations of the section and a manual interpretation.     

视频分割技术的发展

随着MPEG－4和MPEG－7的研究发展以及最近几年数字视频图书馆技术的崛起,基于内容编码和面向对象的存取和操纵技术日益受到人们的重视,视频分割技术迅速成为当前视频研究领域的热点。视频分割是新一代视频编码、视频检索、互联网多媒体交互等新兴领域的关键技术。介绍了视频分割的主要技术,对其算法和性能进行了比较和评述,并分析了当前视频分割技术的研究现状、尚存在的问题和研究前景。     

图卷积神经网络在点云语义分割中的研究综述

点云数据蕴含丰富的空间信息,可以通过激光雷达、3D传感器等设备大量采集,被广泛应用于自动驾驶、虚拟现实、城市规划和3D重建等领域。点云语义分割作为3D场景理解、识别和各种应用的基础而受到广泛关注。但不规则的点云数据无法直接作为传统卷积神经网络的输入,而图卷积神经网络可以利用图卷积算子直接对点云数据进行特征提取,使得图卷积神经网络已逐步成为点云语义分割领域的一个重要研究方向。基于此,对图卷积神经网络在3D点云语义分割应用中的研究进展进行综述,根据图卷积的类型对基于图卷积神经网络的点云语义分割方法进行分类,按照不同类别对比分析主流方法的模型架构及其特点,描述几个相关点云语义分割领域常用的公共数据集和评价指标,对点云语义分割方法进行总结和展望。     

A survey of methods and strategies in character segmentation

Character segmentation has long been a critical area of the OCR process. The higher recognition rates for isolated characters vs. those obtained for words and connected character strings well illustrate this fact. A good part of recent progress in reading unconstrained printed and written text may be ascribed to more insightful handling of segmentation. This paper provides a review of these advances. The aim is to provide an appreciation for the range of techniques that have been developed, rather than to simply list sources. Segmentation methods are listed under four main headings. What may be termed the “classical” approach consists of methods that partition the input image into subimages, which are then classified. The operation of attempting to decompose the image into classifiable units is called “dissection.” The second class of methods avoids dissection, and segments the image either explicitly, by classification of prespecified windows, or implicitly by classification of subsets of spatial features collected from the image as a whole. The third strategy is a hybrid of the first two, employing dissection together with recombination rules to define potential segments, but using classification to select from the range of admissible segmentation possibilities offered by these subimages. Finally, holistic approaches that avoid segmentation by recognizing entire character strings as units are described     

基于视觉的人体行为识别算法研究综述*

人体行为识别应用广泛,是人工智能领域研究的热点问题,针对人体行为识别算法进行归纳总结,具有很重要的参考价值。以行为识别为核心,同时包含数据集、动作分割等内容。引言部分主要讲述人体行为识别的基础流程,数据集部分归纳了人体行为识别常用的数据集,动作分割方法总结了时域分割的发展现状和常用的方法,传统方法讲解了人体行为识别比较经典的方法,深度学习方法归纳了人体行为识别最新最热的深度学习方法。引入了动作分割,再结合行为识别,能够实现连续的人体行为识别,使得行为识别适用于实际场景,而不再是对经过人工剪辑好的单个视频进行识别,这在实际应用中意义重大。     

字符粘连及字线相交的分割与识别方法

描述了工程图纸矢量化中多向粘连字符及字线相交的分割算法与识别方法.提出不同情况下字串的定向计算方法,通过粘连字块的特征矢量计算和迭代计算实现字块的分割.运用波形投影方法解决了粘连字符及字线相交情况下的字间切割问题,使工程图多向字符识别精度显著提高,该算法对局部退化状态下的字符识别具有良好的抗干扰性.     

Adaptive potential active contours

In this paper potential active contours are presented as a new method of image segmentation. The concept of potential contour is a result of the relationship between active contour techniques and the methods of classifiers’ construction. The proposed method can be extended by the adaptation mechanism that allows changing the available class of the shapes dynamically. An original contribution is also the method of evaluation of segmentation results and methodology used for the parameters selection. The described method is illustrated by two examples.     

Monotonic sequences for image enhancement and segmentation

Both image enhancement and image segmentation are important pre-processing steps for various image processing fields including autonomous navigation, remote sensing, computer vision, and biomedical image analysis. Both methods have their merits and their short comings. It then becomes obvious to ask the question: is it possible to develop a new better image enhancement method which has the key elements from both segmentation and image enhancement techniques? The choice of the threshold level is a key task in image segmentation. There are other challenges of image segmentation. For example, it is very difficult to perform the image segmentation in poor data such as shadows and noise. Recently, a homothetic curves Fibonacci-based cross sections thresholding has been developed for the de-noising purposes. Is it possible to develop a new image cross sections thresholding method, which can be used for both segmentation and image enhancement purposes? This paper a) describes a unified approach for signal thresholding, b) extends cross sections concept by generating and using a new class of monotonic, piecewise linear, sequences (slowly or faster growing than Fibonacci numbers) of numbers; c) uses the extended sections concept to the image enhancement and segmentation applications. Extensive experimental evaluation demonstrates that the newly proposed monotonic sequences have great potential in image processing applications, including image segmentation and image enhancement applications. Moreover, study has shown that the generalized cross techniques are invariant under morphological transformations such as erosion, dilation, and median, able to be described analytically, can be implemented by using the look up table methods.     

基于区域的烟尘图像分割方法

烟尘图像分割是图像分割方法的一个较新的应用方向。高效、准确的烟尘图像分割技术对于大气污染监控、森林火灾预警以及军事情报获取等方面都有重要的意义。将阈值分割、区域生长、区域分裂与合并等基于区域的方法用于烟尘图像分割,并对三种分割方法在烟尘图像分割中的性能表现进行了分析。研究结果对烟尘图像分割中算法的选型具有一定的参考价值。     

基于商空间粒度理论的三维网格分割方法

通过研究已有的网格分割和模型简化方法 ,分析三维模型的网格分割中的商空间粒度思想 ,并将商空间粒度计算引入到网格分割中 ,对网格分割过程进行描述 ,提出了基于粒度分层合成技术的网格分割方法。该算法通过分别提取模型中各三角形网格区域的几何特征构成不同的粒度区域 ,再根据粒度合成理论。将这些所形成的粒度组织起来 ,从而实现对三维网格的最终分割 ,为三角网格模型的简化提供了快速有效的方法。实验表明了该算法对于网格分割的有效性和正确性。     

胎儿脑磁共振图像分割研究进展

医学影像是产前筛查、诊断、治疗引导和评估的重要工具,能有效避免胎儿脑的发育异常。近年来,磁共振成像在产前诊断中愈加重要,而实现自动、定量、精确地分析胎儿脑磁共振图像依赖于可靠的图像分割。因此,胎儿脑磁共振图像分割具有十分重要的临床意义与研究价值。由于胎儿图像中存在组织器官多、图像质量差及结构变化快等问题,胎儿脑磁共振图像的分割面临着巨大的困难与挑战。目前,尚未有文献对该领域的方法进行系统性的总结和分析,尤其是基于深度学习的方法。本文针对胎儿脑磁共振图像分割方法进行综述,首先,对胎儿脑磁共振图像的主要公开图谱/数据集进行详细说明;接着,对脑实质提取、组织分割和病灶分割方法进行全面的分类与分析;最后,对胎儿脑磁共振图像分割面临的挑战及未来的研究方向进行总结与展望。     

Survey on liver CT image segmentation methods

The segmentation of liver using computed tomography (CT) data has gained a lot of importance in the medical image processing field. In this paper, we present a survey on liver segmentation methods and techniques using CT images, recent methods presented in the literature to obtain liver segmentation are viewed. Generally, liver segmentation methods are divided into two main classes, semi-automatic and fully automatic methods, under each of these two categories, several methods, approaches, related issues and problems will be defined and explained. The evaluation measurements and scoring for the liver segmentation are shown, followed by the comparative study for liver segmentation methods, pros and cons of methods will be accentuated carefully. In this paper, we concluded that automatic liver segmentation using CT images is still an open problem since various weaknesses and drawbacks of the proposed methods can still be addressed.