Temporal video segmentation and classification of edit effects

The process of shot break detection is a fundamental component in automatic video indexing, editing and archiving. This paper introduces a novel approach to the detection and classification of shot transitions in video sequences including cuts, fades and dissolves. It uses the average inter-frame correlation coefficient and block-based motion estimation to track image blocks through the video sequence and to distinguish changes caused by shot transitions from those caused by camera and object motion. We present a number of experiments in which we achieve better results compared with two established techniques.     

Phonetic segmentation using multiple speech features

In this paper we propose a method for improving the performance of the segmentation of speech waveforms to phonetic units. The proposed method is based on the well known Viterbi time-alignment algorithm and utilizes the phonetic boundary predictions from multiple speech parameterization techniques. Specifically, we utilize the most appropriate, with respect to boundary type, phone transition position prediction as initial point to start Viterbi time-alignment for the prediction of the successor phonetic boundary. The proposed method was evaluated on the TIMIT database, with the exploitation of several, well known in the area of speech processing, Fourier-based and wavelet-based speech parameterization algorithms. The experimental results for the tolerance of 20 milliseconds indicated an improvement of the absolute segmentation accuracy of approximately 0.70%, when compared to the baseline speech segmentation scheme.     

Genetic algorithms for video segmentation

The current paper presents a new genetic algorithm (GA)-based method for video segmentation. The proposed method is specifically designed to enhance the computational efficiency and quality of the segmentation results compared to standard GAs. The segmentation is performed by chromosomes that independently evolve using distributed genetic algorithms (DGAs). However, unlike conventional DGAs, the chromosomes are initiated using the segmentation results of the previous frame, instead of random values. Thereafter, only unstable chromosomes corresponding to moving object parts are evolved by crossover and mutation. As such, these mechanisms allow for effective solution space exploration and exploitation, thereby improving the performance of the proposed method in terms of speed and segmentation quality. These advantages were confirmed based on experiments where the proposed method was successfully applied to both synthetic and natural video sequences.     

视频会议中视频分割合成的研究

视频会议系统正在吸引越来越多在地域上分散的人们的注意。随着多媒体信息处理和通信技术的飞速发展,虚拟视频会议系统越来越成为可能。和传统的基于二维图像表述的视频会议系统比较,三维虚拟会议系统能为人们提供更好的以人为中心的交流。在这两种情况下,高效精确的视频分割和视图合成都是关键问题。就以下3方面的主要技术进行了研究：背景分离、视差估计以及视图合成。     

Temporal segmentation of video using frame and histogram space

Two algorithms are presented for the detection of gradual transitions in video sequences. The first is a dissolve detection algorithm utilizing certain properties of a dissolve's trajectory in image-space. It is implemented both as a simple threshold-based detector, and as a parametric detector by modeling the error properties of the extracted statistics. The second is an algorithm to detect a wide variety of wipes based on image histogram characteristics during such transitions. Both algorithms operate in the compressed domain, requiring only partial decoding of the compressed video stream. Experiments show the algorithms perform as well as-and in some cases, better than-full-frame methods, on a wide variety of gradual transitions, and can operate significantly faster than real-time.     

视频监控系统中的图像分割算法综述*

视频监控系统在智能安防、人机交互、交通、娱乐、军事等领域有着广泛的应用空间,是近来研究热点之一。目标的分割是视频监控系统中的首要任务,其分割的有效性对于后续的目标识别、跟踪、行为理解等处理至关重要。从时间分割法和空间分割法的分类角度出发,对国内外的视频监控研究中的若干目标分割方法进行了归纳总结。     

Non-interactive automatic video segmentation of moving targets

Extracting moving targets from video accurately is of great significance in the field of intelligent transport.To some extent,it is related to video segmentation or matting.In this paper,we propose a non-interactive automatic segmentation method for extracting moving targets.First,the motion knowledge in video is detected with orthogonal Gaussian-Hermite moments and the Otsu algorithm,and the knowledge is treated as foreground seeds.Second,the background seeds are generated with distance transformation based on foreground seeds.Third,the foreground and background seeds are treated as extra constraints,and then a mask is generated using graph cuts methods or closed-form solutions.Comparison showed that the closed-form solution based on soft segmentation has a better performance and that the extra constraint has a larger impact on the result than other parameters.Experiments demonstrated that the proposed method can effectively extract moving targets from video in real time.     

Handwritten document image segmentation into text lines and words

Two novel approaches to extract text lines and words from handwritten document are presented. The line segmentation algorithm is based on locating the optimal succession of text and gap areas within vertical zones by applying Viterbi algorithm. Then, a text-line separator drawing technique is applied and finally the connected components are assigned to text lines. Word segmentation is based on a gap metric that exploits the objective function of a soft-margin linear SVM that separates successive connected components. The algorithms tested on the benchmarking datasets of ICDAR07 handwriting segmentation contest and outperformed the participating algorithms.     

融合时空多特征表示的无监督视频分割算法

针对视频分割的难点在于分割目标的无规则运动、快速变换的背景、目标外观的任意变化与形变等,提出了一种基于时空多特征表示的无监督视频分割算法,通过融合像素级、超像素级以及显著性三类特征设计由细粒度到粗粒度的稳健特征表示。首先,采用超像素分割对视频序列进行处理以提高运算效率,并设计图割算法进行快速求解;其次,利用光流法对相邻帧信息进行匹配,并通过K-D树算法实现最近邻搜索以引入各超像素的非局部时空颜色特征,从而增强分割的鲁棒性;然后,对采用超像素计算得到的分割结果,设计混合高斯模型进行完善;最后,引入图像的显著性特征,协同超像素分割与混合高斯模型的分割结果,设计投票获得更加准确的视频分割结果。实验结果表明,所提算法是一种稳健且有效的分割算法,其结果优于当前大部分无监督视频分割算法及部分半监督视频分割算法。     

改进的一种图论分割方法在舌像分割中的应用

由于人舌体的特殊性质,从舌像中直接分割舌体时常存在过分割和过合并现象。针对舌像特点提出了一种结合图论分割和多分辨率分割的图像分割算法,用一种图论分割算法让舌像在两种分辨率下分别进行分割,根据两种分割的结果把它们进行交或者并处理,从而有效地分割出舌体。实验结果表明这种方法能够有效避免直接使用图论分割时出现分割过度或者欠分割的情况。     

一种语料缺乏条件下的藏语音素自动切分方法

藏语语音合成及语音学研究中,经常需要切分音素。人工切分费时费力,但是由于藏语语料缺乏,训练的藏语声学模型不够精确和鲁棒,自动切分的音素边界不够准确。以藏语拉萨方言为研究对象,在确定拉萨方言音素集、建立拉萨方言发音词典的基础上,通过计算音素模型间的距离,确定了拉萨方言和英语的共同音素,融合拉萨方言和英语GMM HMM模型,并自动判断语音中的静音和短时停顿,构造语音对应的词网络,查询发音词典,将词网络扩展为模型（音素）网络,使用Viterbi算法将每一帧特征参数对应到模型的每一个状态上,进而对音素进行切分。实验表明,切分效果要优于单纯的藏语模型方法。     

基于内容检索的视频分割技术的研究

视频分割就是从视频序列中分割出在语义上有意义的对象。目前，视频分割已从基于镜头的分割发展到了基于内容的视频对象分割。文章介绍了基于内容的时域及空域视频分割技术，提出了一种基于多帧差异的视频对象分割算法。     

一种视频序列拼接的新方法

提出了一种基于视频序列拼接的新方法。首先,利用KLT算法对视频序列中特征点进行提取和跟踪,实现关键帧粗略选取;其次,在选取的关键帧中利用SURF算法进行特征提取,利用最近邻距离比进行特征点匹配,通过RANSAC估计算法求精单映矩阵,并结合关键帧选取判定寻找最佳关键帧;最后,利用级联单映矩阵和加权融合算法实现视频序列拼接。实验验证了该方法的有效性。     

融合视觉词与自注意力机制的视频目标分割

目的 视频目标分割(video object segmentation, VOS)是在给定初始帧的目标掩码条件下,实现对整个视频序列中感兴趣对象的分割,但是视频中往往会出现目标形状不规则、背景中存在干扰信息和运动速度过快等情况,影响视频目标分割质量。对此,本文提出一种融合视觉词和自注意力机制的视频目标分割算法。方法 对于参考帧,首先将其图像输入编码器中,提取分辨率为原图像1/8的像素特征。然后将该特征输入由若干卷积核构成的嵌入空间中,并将其结果上采样至原始尺寸。最后结合参考帧的目标掩码信息,通过聚类算法对嵌入空间中的像素进行聚类分簇,形成用于表示目标对象的视觉词。对于目标帧,首先将其图像通过编码器并输入嵌入空间中,通过单词匹配操作用参考帧生成的视觉词来表示嵌入空间中的像素,并获得多个相似图。然后,对相似图应用自注意力机制捕获全局依赖关系,最后取通道方向上的最大值作为预测结果。为了解决目标对象的外观变化和视觉词失配的问题,提出在线更新机制和全局校正机制以进一步提高准确率。结果 实验结果表明,本文方法在视频目标分割数据集DAVIS(densely annotated video segme...     

汉语文本自动分词算法的研究

分析了中文分词词典的机制,提出了一种改进的整词分词字典结构,并针对机械分词算法的特点,将其与概率算法相结合,探讨了一种中文自动分词概率算法。采用哈希及二分法对词典进行分词匹配。实验表明,该算法具有较高的分词效率和准确率,对于消去歧义词也有较好的性能。     

Spatiotemporal video segmentation and motion estimation through irregular pyramids

This paper presents a new spatiotemporal segmentation technique for video sequences. It relies on building irregular pyramids based on its homogeneity over consecutive frames. Pyramids are interlinked to keep a relationship between the regions in the frames. Its performance is good in real-world conditions because it does not depend on image constrains.     

嵌入式系统中视频运动对象分割

提出了一种基于嵌入式系统的视频运动对象分割算法。首先利用差图像法抽取出运动的像素点,然后通过统计像素点的状态变化频率来区分运动物体和动态背景,并配合一权值状态矩阵将全局光照突变和动态背景像素自适应融合到背景中,从而分割出运动对象并进行跟踪。实验结果表明,该算法在嵌入式系统中实时跟踪运动目标取得了很好的效果。     

C-V模型在红外视频火灾图像分割中的应用

针对大空间中红外视频火灾图像边缘模糊,不易准确分割问题,研究了一种基于背景差分和C-V模型的分割方法。通过背景差分得到运动图像;利用形态学处理得到完整的运动区域,并获得其外接矩形;以外接矩形作为C-V模型的初始轮廓曲线进行分割,得到封闭、完整的运动目标轮廓。该算法避免了对整幅图像分割,减少了运算量。通过实验仿真并与阈值分割算法比较,证明了该算法的准确性和有效性,有利于下一步火灾特征提取与识别。