In this paper, we propose a multiphase image segmentation method via solving the min-cut minimization problem under the multigrid method framework. At each level of the multigrid method for the min-cut problem, we fir...
详细信息
In this paper, we propose a multiphase image segmentation method via solving the min-cut minimization problem under the multigrid method framework. At each level of the multigrid method for the min-cut problem, we first transfer it to the equivalent form, e.g., max-flow problem, then actually solve the dual of the max-flow problem. Particularly, a classical multigrid method is used to solve the sub-minimization problems. Several outer iterations are used for the multigrid method. The proposed idea can be used for general min-cut/max-flow minimization problems. We use multiphase image segmentation as an example in this work. Extensive experiments on simulated and real images demonstrate the efficiency and effectiveness of the proposed method.
In this paper, a new model based on variational level set method for segmenting multiphaseimages is proposed. Its energy functional is based on the level set functions and the regional characteristics functions. It c...
详细信息
ISBN:
(纸本)9780769536583
In this paper, a new model based on variational level set method for segmenting multiphaseimages is proposed. Its energy functional is based on the level set functions and the regional characteristics functions. It can deal with changes in curves' topology and be extended to multiphase image segmentation models which are based on other schemes for region competition as well. The gradient flow of the energy functional is computed using variational method to get the optimized solution of the model. In order to guarantee more accurate calculation, discrete definition of level set functions is used. Experimental results show that the new model has promising effect on imagesegmentation.
The Vese-Chan model for multiphase image segmentation uses m binary label functions to construct 2(m) characteristic functions for different phases/regions systematically;the terms in this model have moderate degrees ...
详细信息
The Vese-Chan model for multiphase image segmentation uses m binary label functions to construct 2(m) characteristic functions for different phases/regions systematically;the terms in this model have moderate degrees comparing with other schemes of multiphasesegmentation. However, if the number of desired regions is less than 2(m), there exist some empty phases which need costly parameter estimation for segmentation purpose. In this paper, we propose an automatic construction method for characteristic functions via transformation between a natural number and its binary expression, and thus, the characteristic functions of empty phases can be written and recognized naturally. In order to avoid the redundant parameter estimations of these regions, we add area constraints in the original model to replace the corresponding region terms to preserve its systematic form and achieve high efficiency. Additionally, we design the alternating direction method of multipliers (ADMM) for the proposed modified model to decompose it into some simple sub-problems of optimization, which can be solved using Gauss-Seidel iterative method or generalized soft thresholding formulas. Some numerical examples for gray images and color images are presented finally to demonstrate that the proposed model has the same or better segmentation effects as the original one, and it reduces the estimation of redundant parameters and improves the segmentation efficiency.
This paper concerns multiphase piecewise smooth imagesegmentation with intensity inhomogeneities. Traditional methods based on the Mumford-Shah (MS) model require solving complicated diffusion equations evolving in i...
详细信息
This paper concerns multiphase piecewise smooth imagesegmentation with intensity inhomogeneities. Traditional methods based on the Mumford-Shah (MS) model require solving complicated diffusion equations evolving in irregular sub-domains, leading to significant difficulties in efficient and accurate segmentation, especially in multiphase scenarios. In this paper, we propose a general framework to modify the MS model by using smoothing operators that can avoid the complicated implementation and inaccurate segmentation of traditional approaches. A detailed analysis connecting the smoothing operators and the diffusion equations is given to justify the modification. In addition, we present an efficient algorithm based on the direct augmented Lagrangian method, which requires fewer parameters than the commonly used augmented Lagrangian method. Typically, the smoothing operator in the general model is chosen to be Gaussian kernel, the bilateral kernel, and the directional diffusion kernel, respectively. Ample numerical results are provided to demonstrate the efficiency and accuracy of the modified model and the proposed minimization algorithm through various comparisons with existing approaches.
In this article, we propose a new variational model for segmenting images with intensity inhomogeneity. The proposed model applies simultaneously the local constant and global smoothness priors to describe the bias pa...
详细信息
In this article, we propose a new variational model for segmenting images with intensity inhomogeneity. The proposed model applies simultaneously the local constant and global smoothness priors to describe the bias part such that our model can obtain more precise segmentation results. This is different from the existing models in which either of such two priors is considered. Also, our method is developed to segment the multiphase inhomogeneous image with noise. Theoretically, we show the existence of minimizers of the proposed variational model. Moreover, by using the alternating minimization method, we design an effective algorithm to numerically solve the solution of the model. Numerical experimental results are provided to verify the better performance of our method than other test methods. (C) 2021 Elsevier Inc. All rights reserved.
We propose a model to recolor textile images by different color themes. The model contains three phases. The first phase is to partition an input textile image into several homogeneous regions. The CIELab color mean o...
详细信息
We propose a model to recolor textile images by different color themes. The model contains three phases. The first phase is to partition an input textile image into several homogeneous regions. The CIELab color mean of each region and a bias-field function are obtained from the segmentation results. The combination of the color mean values of all regions is considered as the color theme of the input image. The second phase is to retrieve the relevant color themes from a given dataset. The retrieved color themes preserve the color mood of the input image in the sense of the similarity measurement defined in the color mood space. In the third phase, we reconstruct new images with different appearances from the input image by using the retrieved color themes. The proposed method provides a powerful tool for designers to generate and search for all relevant color combinations related to a given theme. Numerical results indicate that our recolorization model performs well on complex textile design patterns.
Potts model is a basic variational model for multiphase image segmentation. Under the variational level set framework, the model is usually implemented by solving a gradient descent equation derived from energy functi...
详细信息
ISBN:
(纸本)9781467329644;9781467329637
Potts model is a basic variational model for multiphase image segmentation. Under the variational level set framework, the model is usually implemented by solving a gradient descent equation derived from energy functional minimization together with re-initialization process to preserve the level set function as a signed distance function. Because of the existence of complicated curvature terms in the PDE equations and the time-consuming re-initialization process, this method is with low computation efficiency. In this paper, we combine the Split Bregman algorithm, Dual method together with a very simple projection method to overcome the problems mentioned above. We name these two methods as Split Bregman Projection Method(SBPM) and Dual Split Bregman Projection Method(DSBPM). They naturally preserve the level set function as a signed distance function during the evolution without the initialization process. These methods are compared with traditional method and the ones proposed by other authors according to some numerical experiments. These examples demonstrate that our proposed methods are of higher efficiency than the other ones and can segment images quickly.
Potts model is a basic variational model for multiphase image segmentation. Under the variational level set framework, the model is usually implemented by solving a gradient descent equation derived from energy functi...
详细信息
ISBN:
(纸本)9781467329637
Potts model is a basic variational model for multiphase image segmentation. Under the variational level set framework, the model is usually implemented by solving a gradient descent equation derived from energy functional minimization together with re-initialization process to preserve the level set function as a signed distance function. Because of the existence of complicated curvature terms in the PDE equations and the time-consuming re-initialization process, this method is with low computation efficiency. In this paper, we combine the Split Bregman algorithm, Dual method together with a very simple projection method to overcome the problems mentioned above. We name these two methods as Split Bregman Projection Method (SBPM) and Dual Split Bregman Projection Method (DSBPM). They naturally preserve the level set function as a signed distance function during the evolution without the initialization process. These methods are compared with traditional method and the ones proposed by other authors according to some numerical experiments. These examples demonstrate that our proposed methods are of higher efficiency than the other ones and can segment images quickly.
暂无评论