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1.
目的在彩色图像采集过程中,光源偏暗或曝光不足等因素常导致图像亮度和对比度偏低。提出一种基于颜色恒常性的低照度图像增强方法。方法利用HSV颜色空间消除颜色分量之间的相关性。保持色调分量不变,避免颜色失真;一方面使用改进后的MSR(多尺度Retinex)算法对亮度分量进行增强,提高图像的亮度和对比度;另一方面对饱和度分量进行自适应非线性拉伸以提高颜色的饱和度。结果提出的方法能够有效提高图像的对比度和信息熵,获得较好的视觉效果;将文中方法同传统MSR算法和MSRCR算法进行对比,文中方法各项客观评价指标均优于其他2种算法,并且具有更快的运行速度。结论文中方法能够快速有效地提高低照度图像的亮度和对比度,并且具有较强的颜色保真和细节再现能力,实验结果证明了文中方法的有效性。  相似文献   

2.
本论文提出了一种新颖的彩色图像水印方案。研究发现与RGB颜色空间线性相关、分量无关的颜色空间对水印应用最适合。本水印方案对彩色图像的自适应是通过把PSNR值保持在一定的品质范围之内,同时调整水印强度参数来达到的。水印是盲水印,即只需要水印的生成和随机系数密钥,并不需要原始图像。实验结果显示了该方法对一些常见的图像处理攻击具有鲁棒性,水印检测结果准确,且算法的计算量合理。  相似文献   

3.
本论文提出了一种新颖的彩色图像水印方案.研究发现与RGB颜色空间线性相关、分量无关的颜色空间对水印应用最适合.本水印方案对彩色图像的自适应是通过把PSNR值保持在一定的品质范围之内,同时调整水印强度参数来达到的.水印是盲水印,即只需要水印的生成和随机系数密钥,并不需要原始图像.实验结果显示了该方法对一些常见的图像处理攻击具有鲁棒性,水印检测结果准确,且算法的计算量合理.  相似文献   

4.
针对图像传感器的多聚焦成像问题,提出了一种基于YIQ颜色模型和第二代Curvelet变换的图像融合方法.通过将待融合图像转换到YIQ颜色模型,考虑到图像的颜色各分量相关性和算法的计算复杂度,对亮度分量Y和色度分量I、Q分别采用了不同的融合策略:亮度分量Y进行Curvelet变换,分解后的高频系数采用区域梯度和能量加权相结合的融合准则,低频系数采用能量自适应加权的融合准则,再进行Curvelet逆变换重构得到分量Y,色度分量I、Q分别通过区域信息熵取大的方法得到.将融合得到的三分量进行YIQ逆变换,从而实现多聚焦彩色图像的融合.通过实验对比,算法取得较好的融合效果.  相似文献   

5.
郭睿 《中国科技博览》2011,(32):365-366
运动分割是视频分析的重要基础步骤。本文研究了从视频序列中提取运动目标的算法。该算法将自适应背景建模和彩色图像分割相结合而得到具有精确边缘的运动目标。在背景建模中,采用混合高斯模型描述像素点的状态,利用高斯分布特性区分噪声、背景、运动。彩色图像分割运用MeanShift迭代算法对图像进行颜色聚类得到一致的颜色区域。实验结果表明该的算法在固定场景下能够精确分割运动目标。  相似文献   

6.
杨晟炜  张志华  孔玲君  王茜 《包装工程》2019,40(11):194-202
目的 鉴于传统的红外与彩色可见光图像融合算法得到的融合图像,无法很好兼顾清晰度、对比度和色彩是否失真等,提出一种新的基于NSST和IHS颜色空间的彩色图像融合算法。方法 首先将源彩色可见光的RGB图像变换到各通道相关性最小的IHS颜色空间,分离出亮度分量和色度分量。其次对彩色可见光的亮度分量和红外图像分别进行NSST分解,对分解得到的低频系数采用基于自适应高斯模糊逻辑函数的系数选择方案,对高频系数则采用基于像素点的绝对值取大的系数选择方案,然后对经过选择的低、高频系数进行NSST逆变换,得到的融合图像作为新的亮度分量,结合已有的色度分量将其进行IHS逆变换,得到最终的RGB融合图像。结果 通过2种场景的红外与彩色可见光图像进行仿真实验,将提出的算法与LPT,SWT和NSCT等算法对比,通过主观评价和客观评价指标IE, AG, SF和SD等,可知新算法的融合结果图像场景细节最清晰,红外隐藏目标对比度最高,且色彩未出现明显失真现象,图像融合质量最高。结论 提出的算法相较于传统的红外与彩色可见光图像的融合质量,全面提升了效果,表明该算法具有优越性。  相似文献   

7.
聂慧  彭娇 《硅谷》2015,(1):66+59
在图像修复中,传统的全变分(TV)模型因其能有效地对小面积破损区域进行修复而被广泛地使用。但若将其直接应用于彩色图像的修复,往往会因彩色图像中各分量(R,G和B)之间的相关性而给修复的结果带来伪彩色。为了解决这一问题,本文在TV模型的基础上提出了一种基于KL变换的彩色图像修复算法(KLTV算法)。该算法首先采用KL变换将彩色图像中R、G、B三个分量的相关性去除以得到三个独立的图像分量,然后运用TV模型对这三个独立分量分别进行修复。实验结果表明,相较于传统的修复算法,KLTV算法不仅可以确保图像修复后的视觉效果,而且可以确保图像修复后的图像质量。  相似文献   

8.
基于数学形态学的HSI空间彩色边缘检测方法   总被引:1,自引:0,他引:1  
针对在RGB空间中很难有效区分颜色相似性的问题,选择更加符合颜色视觉特性的HSI颜色空间进行图像处理,提出一种基于HSI空间的多结构多尺度自适应彩色图像边缘检测方法.首先对H、S、I三个分量采用不同结构和不同尺度的结构元素进行形态学边缘检测,然后对三个边缘分量利用信息熵加权得到融合后的彩色边缘信息.实验结果表明,该方法可以充分利用彩色图像的色度,饱和度和亮度信息,有效地抑制噪声,自适应地提取完整的边缘信息.  相似文献   

9.
基于多小波变换和分块SVD的彩色图像水印算法   总被引:3,自引:0,他引:3  
提出了一种基于多小波变换和分块SVD的非盲水印算法。选择彩色图像的饱和度分量作为水印的嵌入域,水印为有意义的灰度图像,水印经Arnold置乱后被嵌入到饱和度分量多小波变换的不同中频区域中。实验证明,该算法不仅对噪声、JPEG压缩、剪切及Photoshop处理具有很好的鲁棒性,而且能抵抗旋转、放缩和平移等几何攻击。  相似文献   

10.
考虑到立体匹配过程中存在的不确定性和模糊性,将已经获得广泛应用的模糊理论引入立体匹配领域,使用与人类感知相似的模糊逻辑为基础的HVS彩色图像点颜色相似性测度,然后把这种模糊颜色相似性测度应用到区域匹配方法的多窗口选择和自适应窗口尺寸缩减当中,最后用SSD方法实现了彩色图像的立体匹配.实验结果表明,该方法具有更高的匹配精确性.  相似文献   

11.
A perennial question in modern weather forecasting and climate prediction is whether to invest resources in more complex numerical models or in larger ensembles of simulations. If this question is to be addressed quantitatively, then information is needed about how changes in model complexity and ensemble size will affect predictive performance. Information about the effects of ensemble size is often available, but information about the effects of model complexity is much rarer. An illustration is provided of the sort of analysis that might be conducted for the simplified case in which model complexity is judged in terms of grid resolution and ensemble members are constructed only by perturbing their initial conditions. The effects of resolution and ensemble size on the performance of climate simulations are described with a simple mathematical model, which is then used to define an optimal allocation of computational resources for a range of hypothetical prediction problems. The optimal resolution and ensemble size both increase with available resources, but their respective rates of increase depend on the values of two parameters that can be determined from a small number of simulations. The potential for such analyses to guide future investment decisions in climate prediction is discussed.  相似文献   

12.
With the advancement in medical data acquisition and telemedicine systems, image compression has become an important tool for image handling, as the tremendous amount of data generated in medical field needs to be stored and transmitted effectively. Volumetric MRI and CT images comprise a set of image slices that are correlated to each other. The prediction of the pixels in a slice depends not only upon the spatial information of the slice, but also the inter-slice information to achieve compression. This article proposes an inter-slice correlation switched predictor (ICSP) with block adaptive arithmetic encoding (BAAE) technique for 3D medical image data. The proposed ICSP exploits both inter-slice and intra-slice redundancies from the volumetric images efficiently. Novelty of the proposed technique is in selecting the correlation coefficient threshold (Tϒ) for switching of ICSP. Resolution independent gradient edge detector (RIGED) at optimal prediction threshold value is proposed for intra-slice prediction. Use of RIGED, which is modality and resolution independent, brings the novelty and improved performance for 3D prediction of volumetric images. BAAE is employed for encoding of prediction error image to resulting in higher compression efficiency. The proposed technique is also extended for higher bit depth volumetric medical images (16-bit depth) presenting significant compression gain of 3D images. The performance of the proposed technique is compared with the state-of-the art techniques in terms of bits per pixel (BPP) for 8-bit depth and was found to be 31.21%, 27.55%, 21.89%, and 2.39% better than the JPEG-2000, CALIC, JPEG-LS, M-CALIC, and 3D-CALIC respectively. The proposed technique is 11.86%, 8.56%, 7.97%, 6.80%, and 4.86% better than the M-CALIC, 3D CALIC, JPEG-2000, JPEG-LS and CALIC respectively for 16-bit depth image datasets. The average value of compression ratio for 8-bit and 16-bit image dataset is obtained as 3.70 and 3.11 respectively by the proposed technique.  相似文献   

13.
In this paper, we report a method for nonuniform data-dependent noise prediction (DDNP), in which the noise predictive filters do not have an identical order (number of taps). To accommodate this new architecture, we implemented a partial decision feedback strategy for branch metric computations of the higher order predictive filters. Theoretical analysis and computer simulations show that our proposed DDNP can achieve a better tradeoff between detection performance and computational complexity compared with the previously reported DDNP  相似文献   

14.
王茜  郑斌军  孔玲君  顾萍 《包装工程》2022,43(9):239-248
目的 图像质量评价(IQA)旨在使用计算模型自动衡量和评价图像质量,以代替人类视觉系统的主观意见,并应用到相关实际问题中。方法 首先将参考图像与失真图像进行输入,使用视觉显著性模型计算图像局部相似度的特征映射,并在质量得分池化阶段作为加权函数,同时,针对视觉显著性图作为单一特征映射的不足,增加了梯度幅度,然后将图像进行颜色空间的转化提取颜色特征,最后分配相应的权重来计算图像相似度。结果 在4个大型数据集上的对比测试显示,在保持适度计算复杂度的同时,VSPSI相比其他有代表性的模型在预测精度上得到了一定的提升,特别是在TID2013数据集上的SROCC达到了0.9055。结论 研究结果表明,VSPSI是一个性能优良的IQA方法,在不同数据集和不同失真类型中都有良好的表现,具有较强的鲁棒性,可胜任多类失真图像的客观质量评价,同时可通过优化视觉显著性模型进一步提升VSPSI的性能。  相似文献   

15.
Ma  Anqi  Liu  Yu  Xu  Xiujuan  Dong  Tao 《Scientometrics》2021,126(8):6803-6823

Predicting the impact of academic papers can help scholars quickly identify the high-quality papers in the field. How to develop efficient predictive model for evaluating potential papers has attracted increasing attention in academia. Many studies have shown that early citations contribute to improving the performance of predicting the long-term impact of a paper. Besides early citations, some bibliometric features and altmetric features have also been explored for predicting the impact of academic papers. Furthermore, paper metadata text such as title, abstract and keyword contains valuable information which has effect on its citation count. However, present studies ignore the semantic information contained in the metadata text. In this paper, we propose a novel citation prediction model based on paper metadata text to predict the long-term citation count, and the core of our model is to obtain the semantic information from the metadata text. We use deep learning techniques to encode the metadata text, and then further extract high-level semantic features for learning the citation prediction task. We also integrate early citations for improving the prediction performance of the model. We show that our proposed model outperforms the state-of-the-art models in predicting the long-term citation count of the papers, and metadata semantic features are effective for improving the accuracy of the citation prediction models.

  相似文献   

16.
This paper deals with the surface modification of commercially pure titanium by using pulsed nanocrystalline plasma electrolytic carburizing. In order to fully characterize the complex underlying mechanism of this process and evaluate the effects of a thorough range of frequencies, a prediction model is developed using a hybrid of Neural Networks and Genetic Algorithms (GA). Process variables, i.e. time, frequency and corrosion resistance of nanocrystalline carbides, have been experimentally studied. Corrosion resistances were measured by PDS technique for different coated samples. A portion of this dataset is used to train the prediction model, while the rest is set aside to test its predictive performance. This hybrid Neural Networks model uses GA to achieve its optimal architecture for prediction. Finally, it is concluded that the proposed model has an excellent prediction capability of final corrosion resistance of nanocrystalline carbides in the various range of frequencies by comparing the results with the experimental data.  相似文献   

17.
根据螺杆式压缩机滑阀容量调节的特点,建立螺杆式压缩机部分负荷性能计算模型,并用螺杆式压缩机性能的实测数据对模型的预测精度进行验证。结果显示:模型预测的螺杆式压缩机部分负荷性能与实测数据吻合,在测试数据范围内,模型预测的最大误差小于2%。  相似文献   

18.
方恩印  杨晟炜  顾萍 《包装工程》2021,42(17):189-196
目的 以色彩管理系统的研发为目标,研究多个因素对正向纽介堡模型颜色预测性能的影响,为模型应用提供参数优化方案.方法 借助Matlab平台模拟基于不同胞元等级、不同检验样本的位置和数量,以及不同胞元个性化修正方案的胞元纽介堡模型,并通过样本打印和测量实验,评价上述各因素对模型颜色预测性能的影响,确定模型的最优参数方案.结果 模型精度随胞元划分等级的增加而提升,但在4或5级胞元后精度逐渐稳定.另外,胞元内采样点数量、位置以及是否采用胞元个性化修正方案,对颜色转换精度都没有产生有效影响.确定将5级胞元划分,胞元中心采样和所有胞元统一修正指数作为胞元纽介堡模型的参数优化方案,与同类型算法模型的比较结果表明,在采样数量一致的情况下,参数优化的胞元纽介堡模型与i1 Profiler软件,胞元神经网络模型的预测色差都小于1个CIEDE2000色差单位,且相互间的差别都小于0.15,在系统误差范围内,胞元顶点距离插值算法的预测色差则达到了3以上.从算法结构上考虑,神经网络模型需要对所有胞元进行训练建模,计算量较大.结论 综合考虑算法精度和效率,参数优化的胞元纽介堡模型可以满足目前印刷工业中色彩复制的需要.  相似文献   

19.
20.
In order to select an effective approach to predict the pressurization characteristics of cryogenic tank during rocket launching, three computational models, defined as 0-D, 1-D and CFD models, are used to obtain the pressure evolution and thermal performance of a cryogenic tank during pressurized discharge period. Several pressurization cases are computed by all of the three models to evaluate their predictive abilities and effects, respectively. The comparative study shows that for the case with a diffuser-type injector at the tank inlet, the consistent results by the three models are obtained in the most of period, except that 1-D model has a peak departure prediction of pressure value at the beginning of process. All of the three models can be used to predict the pressurization performance, and their predictive abilities could be validated with one another. The CFD model is the unique suitable model to display the pressurization performance including physical distribution in radial direction especially for the system with no-diffuser-type injector. Based on the analysis, the application selection of three models for different cases is accomplished. The 0-D model is the priority selection for a simple pressure prediction of tank ullage, even for the situation that severe temperature distribution exists in the ullage range. The 1-D model is the optimal selection as considering both the convenience and the time consumption for the constant-pressure cases. But it is not recommended in a constant-inlet flux cases for its distinct predicting deviation at the beginning of the process. When the detailed distributions within the tank are concerned, the CFD model is the unique selection. The results of this paper may be beneficial to the model selection and optimization analysis of a pressurization system.  相似文献   

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