Text-aware balloon extraction from manga

Manga, a Japanese word for comics, is a worldwide popular visual entertainment. Nowadays, electronic devices boost the fast development of motion manga for the purpose of visual richness and manga promotion. To convert static manga images into motion mangas, text balloons are usually animated individually for better story telling. This needs the artists to cut out each text balloon meticulously, and therefore it is quite labor-intensive and time-consuming. In this paper, we propose an automatic approach that can extract text balloons from manga images both accurately and effectively. Our approach starts by extracting white areas that contain texts as text blobs. Different from existing text blob extraction methods that only rely on shape properties, we incorporate text properties in order to differentiate text blobs from texture blobs. Instead of heuristic parameter thresholding, we achieve text blob classification via learning-based classifiers. Along with the novel text blob classification method, we also make the first attempt in trying to tackle the boundary issue in balloon extraction. We apply our method on various styles of mangas and comics with texts in different languages, and convincing results are obtained in all cases.     

具有纹理感知能力的超像素分割方法

目的 超像素分割是计算机视觉领域常用的一项预处理技术,目标是将相邻像素聚集成为具有一定语义的子区域,能够大幅度降低后续处理的计算复杂度,但是对包含强梯度纹理的图像分割效果不佳,为此提出一种具有纹理感知能力的超像素分割方法。方法 提出一种能够区分强梯度噪声和纹理像素的颜色距离,其中利用带方向的1/4圆形窗口均值滤波后的颜色信息,提升包含强梯度噪声和纹理图像的超像素分割性能。利用区间梯度幅值与Sobel梯度幅值相乘得到混合梯度幅值,具有纹理抑制、结构保持以及边缘线条细的优点,能够提升超像素的贴合边缘性能,增强超像素形状规则程度。最后,利用混合梯度的幅值计算具有结构回避能力的综合聚类距离,进一步防止超像素跨越物体的边界,增强超像素的贴边性能。结果 在BSDS500（Berkeley segmentation dataset 500）图像数据集和强纹理马赛克图像等不同类型图像上的测试结果显示,与目前主流的超像素分割方法相比,本文算法在UE （undersegmentation error）、ASA （achievable segmentation accuracy）和CM （compactness measure）等性能指标上分别提高了1.5%、0.2%和4.3%。从视觉效果上看,能够在排除纹理干扰的情况下生成结构边缘贴合程度更好的形状规则超像素。结论 本文算法在包含强梯度纹理图像上的超像素分割性能优于对比方法,在目标识别、目标追踪和显著性检测等易受强梯度干扰的技术领域具有较大应用潜力。     

有限混合纹理模式及其纹理分割框架

受到基于模型和基于结构的纹理分析方法的启发,提出一种新的特征提取方法—有限混合纹理模式。纹理特征采用聚类的方法进行计算,避免了基于模型方法复杂的参数求取过程,同时也突破了基于结构的方法纹理表达能力不足的问题。在该特征的基础上,给出相应的纹理分割框架,并通过定量和定性实验验证了所提算法的有效性。     

Thermo-key: human region segmentation from video

We focus on the segmentation of human regions, an area that has had a significant amount of research. Our approach, is based on invisible thermal information that we can measure without any estimation. In fact, we measure infrared light radiation of the thermal information for keys hence we call our proposed system thermo-key. A color and thermal combination camera measures the temperature distribution of its field of view. This system segments the human region from the video sequence - captured by the color camera in real time - with high robustness against lighting and background conditions.     

复杂纹理图像分割方法研究与实现

复杂纹理分割是图像分割领域的难点之一,给出了基于模糊粒度计算与模糊聚类相结合的分割算法,实验表明该算法对复杂纹理图像分割十分有效。     

预训练驱动的多模态边界感知视觉Transformer

卷积神经网络(convolutional neural network, CNN)在图像篡改检测任务中不断取得性能突破,但在面向真实场景下篡改手段未知的情况时,现有方法仍然无法有效地捕获输入图像的长远依赖关系以缓解识别偏差问题,从而影响检测精度.此外,由于标注困难,图像篡改检测任务通常缺乏精准的像素级图像标注信息.针对以上问题,提出一种预训练驱动的多模态边界感知视觉Transformer.首先,为捕获在RGB域中不可见的细微伪造痕迹,引入图像的频域模态并将其与RGB空间域结合作为多模态嵌入形式.其次利用ImageNet对主干网络的编码器进行训练以缓解当前训练样本不足的问题.然后, Transformer模块被整合到该编码器的尾部,以达到同时捕获低级空间细节信息和全局上下文的目的,从而提升模型的整体表征能力.最后,为有效地缓解因伪造区域边界模糊导致的定位难问题,构建边界感知模块,其可以通过Scharr卷积层获得的噪声分布以更多地关注噪声信息而不是语义内容,并利用边界残差块锐化边界信息,从而提升模型的边界分割性能.大量实验结果表明,所提方法在识别精度上优于现有的图像篡改检测方法,并对不同的...     

一种织物彩色图像的分割算法

提出了一种针对织物彩色图像的分割算法。该算法在颜色聚类的基础上,把每种颜色用 不同的序号来表示,生成一个与原图同大小的序号矩阵,然后根据矩阵中序号的分布进行初始分割并 产生种子区域,再把初始分割未能确定的像素指派到种子区域中,最后根据颜色信息合并过分割的区 域,并对区域边缘进行平滑,得到最终的分割结果。实验表明,该算法能较有效地实现各类彩色织物 图像的分割。     

Unsupervised texture segmentation using Gabor filters

This paper presents a texture segmentation algorithm inspired by the multi-channel filtering theory for visual information processing in the early stages of human visual system. The channels are characterized by a bank of Gabor filters that nearly uniformly covers the spatial-frequency domain, and a systematic filter selection scheme is proposed, which is based on reconstruction of the input image from the filtered images. Texture features are obtained by subjecting each (selected) filtered image to a nonlinear transformation and computing a measure of “energy” in a window around each pixel. A square-error clustering algorithm is then used to integrate the feature images and produce a segmentation. A simple procedure to incorporate spatial information in the clustering process is proposed. A relative index is used to estimate the “true” number of texture categories.     

Target recognition by texture segmentation algorithm

In order to improve the performance of image segmentation, this paper presented a gray level jump segmentation algorithm, which defined the direction of the texture, simultaneously, calculated the width of ridge line, gave the distance characteristics between textures, and established the mathematical model of the texture border, accordingly presented a new texture segmentation algorithm and compared with other texture segmentation algorithms. The simulation results show that the segmentation algorithm has some advantages to texture segmentation, such as has higher segmentation precision, faster segmentation speed, stronger anti-noise capability, less lost information of target, and so on. The segmented regions hardly contain other texture regions and background region. Moreover, this paper extracted the characteristic points and characteristic parameters in various segmented regions for texture image to obtain the characteristic vector, compared the characteristic vector with the standard template vectors, and identified the type of target in a range of threshold value. Experimental results show that the proposed target recognition approach has higher recognition rate and faster recognition speed than the existing target recognition approaches. Advancements in image processing through the study of texture segmentation are not only applicable to image fields, but also are of important theoretical value to target recognition. These researches in this paper will play an important role in a theoretical reference and practical significance to the development of all target recognition departments based on image system such as the aerospace, public security, road traffic, and so on.     

Independent component analysis for texture segmentation

Independent component analysis (ICA) of textured images is presented as a computational technique for creating a new data dependent filter bank for use in texture segmentation. We show that the ICA filters are able to capture the inherent properties of textured images. The new filters are similar to Gabor filters, but seem to be richer in the sense that their frequency responses may be more complex. These properties enable us to use the ICA filter bank to create energy features for effective texture segmentation. Our experiments using multi-textured images show that the ICA filter bank yields similar or better segmentation results than the Gabor filter bank.     

Multi-resolution texture segmentation using fractal dimension

An efficient algorithm for segmenting a textured image into different regions is developed based on a set of fractal dimension estimated from calculated variorum. An edge detector is employed to detect multi-resolution framework texture boundary based on the including gradient pyramid construction followed by the reliable information obtained in the rough resolution as mask to constrain the calculation region in the rest resolution. Combined with mask and gradient in each resolution is propagating down to the finest resolution giving a more accurate boundaries estimation. The utility of the proposed method is demonstrated on a number Of synthesis and natural textures.     

Performance of dynamic texture segmentation using GPU

This work is focused on the assessment of the use of GPU computation in dynamic texture segmentation under the mixture of dynamic textures (MDT) model. In this generative video model, the observed texture is a time-varying process commanded by a hidden state process. The use of mixtures in this model allows simultaneously handling of different visual processes. Nowadays, the use of GPU computing is growing in high-performance applications, but the adaptation of existing algorithms in such a way as to obtain a benefit from its use is not an easy task. In this paper, we made two implementations, one in CPU and the other in GPU, of a known segmentation algorithm based on MDT. In the MDT algorithm, there is a matrix inversion process that is highly demanding in terms of computing power. We make a comparison between the gain in performance obtained by porting to GPU this matrix inversion process and the gain obtained by porting to GPU the whole MDT segmentation process. We also study real-time motion segmentation performance by separating the learning part of the algorithm from the segmentation part, leaving the learning stage as an off-line process and keeping the segmentation as an online process. The results of performance analyses allow us to decide the cases in which the full GPU implementation of the motion segmentation process is worthwhile.     

Efficient Gabor filter design for texture segmentation

Gabor filters have been successfully applied to a broad range of image processing tasks. The present paper considers the design of a single filter to segment a two-texture image. A new efficient algorithm for Gabor-filter design is presented, along with methods for estimating filter output statistics. The algorithm draws upon previous results that showed that the output of a Gabor-filtered texture is modeled well by a Rician distribution. A measure of the total output power is used to select the center frequency of the filter and is used to estimate the Rician statistics of the Gabor-filtered image. The method is further generalized to include the statistics of postfiltered outputs that are generated by a Gaussian filtering operation following the Gabor filter. The new method typically requires an order of magnitude less computation to design a filter than a previously proposed method. Experimental results demonstrate the efficacy of the method.     

基于Quaternion-Gabor滤波器的彩色纹理分割算法研究

提出一种的简单快速的多通道Gabor滤波技术对彩色纹理进行分割。首先,通过DRBFT和IDRBFT对彩色纹理的进行多通道Gabor滤波,再运用PCA对滤波得到的特征向量进行降维,对降维后的特征向量进行k-mean聚类,最后再对聚类后的区域用mean shift进行平滑,通过对平滑后的区域进行边缘检测就可以得到不同纹理的边界。最后给出几种分割算法的实验结果比较,表明该算法对于分割彩色纹理还是非常有效的。     

MRF-based texture segmentation using wavelet decomposed images

In recent textured image segmentation, Bayesian approaches capitalizing on computational efficiency of multiresolution representations have received much attention. Most of the previous researches have been based on multiresolution stochastic models which use the Gaussian pyramid image decomposition. In this paper, motivated by nonredundant directional selectivity and highly discriminative nature of the wavelet representation, we present an unsupervised textured image segmentation algorithm based on a multiscale stochastic modeling over the wavelet decomposition of image. The model, using doubly stochastic Markov random fields, captures intrascale statistical dependencies over the wavelet decomposed image and intrascale and interscale dependencies over the corresponding multiresolution region image.     

基于纹理检测的骨骼影像分割

针对人体x光图像中的骨骼影像在分割过程中局部出现过度分割或欠分割的现象,提出了一种基于统计区域纹理的检测方法。对检测出不符合分割要求的局部影像,在再次分割前,分别采用补偿灰度或收缩分割区域的方式调整。实验结果表明,该算法能检测出分割后图像的局部性质,并能有效改善过度分割和欠分割的现象,分割后的影像可为下一步的模式识别提供一定的基础。     

Nonlocal active contour model for texture segmentation

Multimedia Tools and Applications - Texture segmentation is a very important subject in the fields of computer vision. In order to segment the textures, active contour model based on nonlocal means...     

Unsupervised texture segmentation in a deterministic annealingframework

We present a novel optimization framework for unsupervised texture segmentation that relies on statistical tests as a measure of homogeneity. Texture segmentation is formulated as a data clustering problem based on sparse proximity data. Dissimilarities of pairs of textured regions are computed from a multiscale Gabor filter image representation. We discuss and compare a class of clustering objective functions which is systematically derived from invariance principles. As a general optimization framework, we propose deterministic annealing based on a mean-field approximation. The canonical way to derive clustering algorithms within this framework as well as an efficient implementation of mean-field annealing and the closely related Gibbs sampler are presented. We apply both annealing variants to Brodatz-like microtexture mixtures and real-word images     

结合纹理去除的遥感图像分割

针对包含复杂纹理信息的遥感图像难以进行精准图像分割的问题,提出了一种结合纹理去除的遥感图像分割方法。首先,改进了相对全变差纹理去除方法,通过引入新的范数约束使相对全变差纹理去除方法可以在去除纹理信息的同时凸显图像中的主要结构,达到辅助分割的效果;然后,使用均值漂移算法对经过纹理去除的遥感图像进行无监督聚类,达到分割的目的;最后,提出的遥感图像分割算法在不同遥感图像上进行了测试。实验结果表明,在高分辨遥感图像的分割上,所提算法可以分割出遥感图像中的主要目标,和直接分割或者结合其他纹理去除方法相比取得了更好的分割结果。所提出的分割算法可以降低纹理信息对图像分割的影响,提高遥感图像分割的精度。     

Multiresolution genetic clustering algorithm for texture segmentation

This work plans to approach the texture segmentation problem by incorporating genetic algorithm and K-means clustering method within a multiresolution structure. As the algorithm descends the multiresolution structure, the coarse segmentation results are propagated down to the lower levels so as to reduce the inherent class–position uncertainty and to improve the segmentation accuracy. The procedure is described as follows. In the first step, a quad-tree structure of multiple resolutions is constructed. Sampling windows of different sizes are utilized to partition the underlying image into blocks at different resolution levels and texture features are extracted from each block. Based on the texture features, a hybrid genetic algorithm is employed to perform the segmentation. While the select and mutate operators of the traditional genetic algorithm are adopted in this work, the crossover operator is replaced with K-means clustering method. In the final step, the boundaries and the segmentation result of the current resolution level are propagated down to the next level to act as contextual constraints and the initial configuration of the next level, respectively.