Unit-Linking PCNN中的彩色图像边缘检测

PCNN模型具有相似群神经元同步发放脉冲的特性,适合于图像分割。对彩色图像的亮度分量进行对数变换,使其更符合人眼的视觉特性;在PCNN进行彩色图像R、G、B三分量分割的过程中,利用遗传算法进行神经元关键参数的选择,利用偏态指标进行迭代控制;在Unit-Linking PCNN模型中实现R、G、B三分量分割图的边缘检测,利用加权合并策略得到最终的边缘检测结果。仿真结果表明,该方法得到的结果体现了图像中更多的轮廓细节,具有很好的自适应性。     

Simplified parameters model of PCNN and its application to image segmentation

Pulse-coupled neural network (PCNN), which simulates the synchronous oscillation phenomenon in the visual cortex of small mammals, has become a useful model for image processing. In the model, several parameters were usually required to properly set for adjusting the behavior of neurons. However, undesired behavior may occur owing to inappropriate parameters setting. To alleviate this problem, we propose to simplify some parameters of PCNN, and apply it into image segmentation. First, exponential delay factors are abandoned for adjusting the neuron input, and the neural input is then associated with image information as well as pulse output. In addition, neural threshold inherent in PCNN is simplified as an adaptive threshold related to image properties, allowing our model to easily alter the behavior of neurons. Particularly, the characteristic of synchronous pulse is thereby kept by introducing a fuzzy clustering method, instead of linking coefficient for grouping pixels with similarity and spatial proximity through iterative computation. Experimental results on synthetic and real infrared images show that the proposed model has high performance of segmentation. Furthermore, our model has better adaptability for segmenting real-world images when compared with several existing PCNN-based methods and some classic segmentation methods.     

High-resolution SAR images segmentation using NSCT denoising and QIGA based parameters selection of PCNN model

The high-resolution synthetic aperture radar (SAR) images usually contain inhomogeneous coherent speckle noises. For the high-resolution SAR image segmentation with such noises, the conventional methods based on pulse coupled neural networks (PCNN) have to face heavy parameters with a low efficiency. In order to solve the problems, this paper proposes a novel SAR image segmentation algorithm based on non-subsampling Contourlet transform (NSCT) denoising and quantum immune genetic algorithm (QIGA) improved PCNN models. The proposed method first denoising the SAR images for a pre-processing based on NSCT. Then, by using the QIGA to select parameters for the PCNN models, such models self-adaptively select the suitable parameters for segmentation of SAR images with different scenes. This method decreases the number of parameters in the PCNN models and improves the efficiency of PCNN models. At last, by using the optimal threshold to binary the segmented SAR images, the small objects and large scales from the original SAR images will be segmented. To validate the feasibility and effectiveness of the proposed algorithm, four different comparable experiments are applied to validate the proposed algorithm. Experimental results have shown that NSCT pre-processing has a better performance for coherent speckle noises suppression, and QIGA-PCNN model based on denoised SAR images has an obvious segmentation performance improvement on region consistency and region contrast than state-of-the-arts methods. Besides, the segmentation efficiency is also improved than conventional PCNN model, and the level of time complexity meets the state-of-the-arts methods. Our proposed NSCT+QIGA-PCNN model can be used for small object segmentation and large scale segmentation in high-resolution SAR images. The segmented results will be further used for object classification and recognition, regions of interest extraction, and moving object detection and tracking.

     

基于区域生长型PCNN模型的织物疵点分割

提出一种新的织物疵点自动分割的方法。该方法将待检测织物图像的像素点映射为脉冲耦合神经网络中的神经元,根据织物疵点图像的特点将改进的脉冲耦合神经网络模型同区域生长的理论结合起来,同时综合无疵点样本织物图像的统计信息完成了图像疵点区域的自动分割。最后,通过对TILDA数据库中疵点图像的检测实验,说明了该方法在织物疵点检测中应用的有效性和可行性。     

一种参数自适应的简化PCNN图像分割方法

为了进一步延伸脉冲耦合神经网络（Pulse coupled neural network,PCNN）在图像分割中的应用,本文对PCNN模型作了简化和改进,并探讨和分析了参数的设置方法.首先利用阈值和脉冲输出所对应的区域均值之间的关系,提出了一种优化连接系数的方法,使得模型最终以迭代的方式得到分割结果.在仿真和真实红外图像上实验结果表明,文中方法能取得较优的分割效果,且相比于常用的阈值方法以及较新的PCNN方法,文中的简化模型对噪声及复杂图像具有更好的适应性和鲁棒性.     

一种基于QPSO的脉冲耦合神经网络参数的自适应确定方法

针对目前脉冲耦合神经网络(PCNN)神经元模型中的参数主要通过人工定义的问题,提出一种基于量子微粒群优化(QPSO)算法的PCNN参数自动确定方法,并分析该算法的时间复杂度。该方法利用PCNN分割后的图像熵作为QPSO算法的适应度函数,在解空间中自动搜索PCNN中待确定参数的最优值,提供一种PCNN神经元模型中的参数自动确定方法。将该方法应用于图像分割时,以互信息量作为图像分割评价标准。仿真结果表明文中方法实现正确的图像分割,其性能优于Otsu方法、人工调整PCNN参数方法、遗传算法优化方法和微粒群优化方法,表现出较好的鲁棒性。     

Temporally sequenced intelligent block-matching and motion-segmentation using locally coupled networks

Motion-based segmentation is a very important capability for computer vision and video analysis. It depends fundamentally on the system's ability to estimate optic flow using temporally proximate image frames. This is often done using block-matching. However, block-matching is sensitive to the presence of observational noise, which is inevitable in real images. Also, images often include regions of homogeneous intensity, where block-matching is problematic. A better method in this case is to estimate motion at the region level. In the approach described in this paper, we have attempted to address the noise-sensitivity and texture-insufficiency problems using a two-pathway system. The pixel-level pathway is a multilayer pulse-coupled neural network (PCNN)-like locally coupled network used to correct outliers in the block-matching motion estimates and produce improved estimates in regions with sufficient texture. In contrast, the region-level pathway is used to estimate the motion for regions with little intensity variation. In this pathway, a PCNN network first partitions intensity images into homogeneous regions, and a motion vector is then determined for the whole region. The optic flows from both pathways are fused together based on the estimated intensity variation. The fused optic flow is then segmented by a one-layer PCNN network. Results on synthetic and real images are presented to demonstrate that the accuracy of segmentation is improved significantly by taking advantage of the complementary strengths and weaknesses of the two pathways.     

基于脉冲耦合神经网络的图像分割

针对传统脉冲耦合神经网络(PCNN)模型在图像分割时需要设置较多参数和不能准确分割低对比度图像的问题,提出一种简化的PCNN模型和改进算法。在简化模型中减少了在传统PCNN模型中需要设置的参数的数量;在改进算法中根据图像像素空间和灰度特征自适应设置模型参数,并根据图像灰度直方图求出灰度期望均值作为图像分割阈值,因此该算法无需选择 循环迭代次数,只需一次点火过程就能实现图像的有效分割。实验结果表明,该方法能准确分割图像,纹理细节清晰,分割结果优于人工调整参数的PCNN方法和Otsu方法。     

Filtering images contaminated with pep and salt type noise with pulse-coupled neural networks

As a typical type of noise in many image related applications, pep and salt (PAS) type noise reduces the quality of the image seriously. Median filter and its variations[1—3] are the earliest filtering algorithms for filtering this type of noise, with the drawback that filtering is performed to all of the pixels in the image, which leads to a severe blur of the filtered image. To tackle this problem, Sun and Neuval[4], and Florencio et al.[5] pre-sented a switch median filtering method whic…     

An Iterative Thresholding Segmentation Model Using a Modified Pulse Coupled Neural Network

This paper presents a novel iterative thresholding segmentation method based on a modified pulse coupled neural network (PCNN) for partitioning pixels carefully into a corresponding cluster. In the modified model, we initially simplify the two inputs of the original PCNN, and then construct a global neural threshold instead of the original threshold under the specified condition that the neuron will keep on firing once it begins. This threshold is shown to be the cluster center of a region in which corresponding neurons fire, and which can be adaptively updated as soon as neighboring neurons are captured. We then propose a method for automatically adjusting the linking coefficient based on the minimum weighted center distance function. Through iteration, the threshold can be made to converge at the possible real center of object region, thus ensuring that the final result will be obtained automatically. Finally, experiments on several infrared images demonstrate the efficiency of our proposed model. Moreover, based on comparisons with two efficient thresholding methods, a number of PCNN-based models show that our proposed model can segment images with high performance.