期刊文献+
共找到5篇文章
< 1 >
每页显示 20 50 100
基于自适应多方向稀疏模型的量化噪声均衡化图像解码方法
1
作者 张臻 施云惠 尹宝才 《北京工业大学学报》 CAS CSCD 北大核心 2014年第4期528-534,共7页
针对量化带来的非一致噪声,基于压缩感知理论,建立了基于量化噪声均衡化模型的图像优化解码方案.针对图像信号纹理的多方向特征,构建了自适应多方向稀疏表示模型.实验结果表明:以变换系数为观测数据,通过基于自适应多方向稀疏模型的量... 针对量化带来的非一致噪声,基于压缩感知理论,建立了基于量化噪声均衡化模型的图像优化解码方案.针对图像信号纹理的多方向特征,构建了自适应多方向稀疏表示模型.实验结果表明:以变换系数为观测数据,通过基于自适应多方向稀疏模型的量化噪声均衡化解码方法可以较大幅度地提高图像重建质量. 展开更多
关键词 压缩感知 方向稀疏算子 均衡化噪声模型
下载PDF
椭圆型最优控制问题中的L^(1,2)-方向稀疏
2
作者 严春梅 张维 《四川理工学院学报(自然科学版)》 CAS 2015年第1期76-79,共4页
介绍一种带有L1,2-方向稀疏项的椭圆型最优控制问题,分析条纹稀疏模式,从理论角度研究该问题的一阶最优性条件。为解决不可微控制问题,基于广义微分,提出一个半光滑牛顿方法,将问题在泛函空间中进行表示和分析,并具有局部超线性收敛率。
关键词 方向稀疏 非光滑正则化 半光滑牛顿
下载PDF
基于Curvelet方向特征的样本块图像修复算法 被引量:11
3
作者 李志丹 和红杰 +1 位作者 尹忠科 陈帆 《电子学报》 EI CAS CSCD 北大核心 2016年第1期150-154,共5页
能否保持修复后图像的结构连贯性和邻域一致性决定了修复性能的优劣.为提高现有样本块修复算法性能,本文提出基于Curvelet变换的样本块图像修复算法.首先利用Curvelet变换估计待修复图像的4方向特征.然后利用颜色信息与方向信息共同衡... 能否保持修复后图像的结构连贯性和邻域一致性决定了修复性能的优劣.为提高现有样本块修复算法性能,本文提出基于Curvelet变换的样本块图像修复算法.首先利用Curvelet变换估计待修复图像的4方向特征.然后利用颜色信息与方向信息共同衡量样本块间的相似度,在此基础上构造颜色-方向结构稀疏度函数.同时根据构造的加权颜色-方向距离寻找合适的多个匹配块,并利用多个匹配块在构造的颜色和方向空间内的邻域一致性约束下稀疏表示目标块,同时根据目标块所处区域特性自适应确定误差容限.实验结果表明提出算法较现有算法可获得更优的修复效果,尤其是在修复富含结构纹理破损类型的图像时. 展开更多
关键词 图像修复 方向特征 加权的颜色-方向距离 颜色-方向结构稀疏 CURVELET变换 稀疏表示
下载PDF
Two-level Bregmanized method for image interpolation with graph regularized sparse coding 被引量:1
4
作者 刘且根 张明辉 梁栋 《Journal of Southeast University(English Edition)》 EI CAS 2013年第4期384-388,共5页
A two-level Bregmanized method with graph regularized sparse coding (TBGSC) is presented for image interpolation. The outer-level Bregman iterative procedure enforces the observation data constraints, while the inne... A two-level Bregmanized method with graph regularized sparse coding (TBGSC) is presented for image interpolation. The outer-level Bregman iterative procedure enforces the observation data constraints, while the inner-level Bregmanized method devotes to dictionary updating and sparse represention of small overlapping image patches. The introduced constraint of graph regularized sparse coding can capture local image features effectively, and consequently enables accurate reconstruction from highly undersampled partial data. Furthermore, modified sparse coding and simple dictionary updating applied in the inner minimization make the proposed algorithm converge within a relatively small number of iterations. Experimental results demonstrate that the proposed algorithm can effectively reconstruct images and it outperforms the current state-of-the-art approaches in terms of visual comparisons and quantitative measures. 展开更多
关键词 image interpolation Bregman iterative method graph regularized sparse coding alternating direction method
下载PDF
Single frame super-resolution reconstruction based on sparse representation
5
作者 谢超 路小波 曾维理 《Journal of Southeast University(English Edition)》 EI CAS 2016年第2期177-182,共6页
In order to effectively improve the quality of recovered images, a single frame super-resolution reconstruction method based on sparse representation is proposed. The combination method of local orientation estimation... In order to effectively improve the quality of recovered images, a single frame super-resolution reconstruction method based on sparse representation is proposed. The combination method of local orientation estimation-based image patch clustering and principal component analysis is used to obtain a series of geometric dictionaries of different orientations in the dictionary learning process. Subsequently, the dictionary of the nearest orientation is adaptively assigned to each of the input patches that need to be represented in the sparse coding process. Moreover, the consistency of gradients is further incorporated into the basic framework to make more substantial progress in preserving more fine edges and producing sharper results. Two groups of experiments on different types of natural images indicate that the proposed method outperforms some state-of- the-art counterparts in terms of both numerical indicators and visual quality. 展开更多
关键词 single frame super-resolution reconstruction sparse representation local orientation estimation principalcomponent analysis (PCA) consistency of gradients
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部