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1.
由于交流等离子体显示器(AC PDP)的显示特性是线性的,因此在显示接收到的视频信号前必须要进行反gamma校正.同时,为了提高显示器件的画质,必须要进行对比度增强.直方图均衡化是一种重要的对比度增强方法,但直方图均衡化的增强效果不可控,往往由于过增强而导致图像失真.本文结合上述两种技术提出了一种应用于AC PDP的反gamma校正与可控的动态对比度增强相结合算法.该算法能够在对输入视频图像进行反gamma校正的同时,实现幅度可调的动态对比度增强.同时避免了传统直方图均衡化对图像产生的过增强现象.本文实现了基于提出算法的实时图像处理器,并且在50英寸AC PDP上进行了测试.模拟仿真及实际测试结果均表明,本文提出的算法能够使AC PDP的画质得到显著提升.  相似文献   

2.
红外图像实时增强的新算法   总被引:10,自引:0,他引:10  
针对红外图像的特点,提出了一种红外图像实时增强的新算法。该算法通过分析图像的直方图,得到图像中目标像素数峰值的估计值,并作为平台直方图均衡化的阈值。用该阈值对直方图进行修正,然后通过修正后的直方图进行直方图均衡化。在FPGA内通过采用并行处理结构及流水线技术实现了该算法,并且每秒可处理25帧128×128×8bits的红外图像。理论分析和实验结果均表明,本算法克服了采用一般直方图均衡化增强红外图像的缺点?对背景和噪声增强过度,抑制了目标的增强。该算法对红外图像增强后,图像对比度是直方图均衡化增强后图像对比度的1.8倍。  相似文献   

3.
针对气象计量自动化温度检定系统中图像噪声大、对比度不够等问题,在采用图像预处理技术的基础上,提出一种同态滤波的对比度受限自适应图像预处理方法。尝试中值滤波对红外图像进行去噪,保证噪声不被增强的前提下,利用同态滤波的原理,对图像细节进行增强。但同态滤波依然存在图像特征点与非特征点在图像质量不高的情况下容易混淆的问题,对此采用限制对比度自适应直方图均衡的方法进一步调整图像的动态范围。通过仿真实验对此方法进行验证,验证了所提出方法的有效性。  相似文献   

4.
一种微弱图像增强技术研究   总被引:5,自引:3,他引:2  
对传统灰度图像直方图均衡化方法进行了深入研究,提出了一种基于正切函数调整的直方图均衡化改进算法,该方法有利于提高图像的对比度,达到对图像判别的要求。 算法实现的关键是最优参数选择,因此采用了一种便于选择最优参数的方法。 另外,将图像相似程度应用于了增强效果的评价,为图像增强的实验分析提供了新的方法,具有一定的科学性与可行性。 实验结果表明,该算法比现有的图像增强方法效果更好。  相似文献   

5.
张雷洪  熊锐 《包装工程》2019,40(13):252-258
目的 针对当前印刷缺陷检测系统中存在的低对比度印刷缺陷检测精度不高等问题,基于HSV颜色空间,提出一种增强的低对比度印刷缺陷识别方法。方法 首先,将标准样张图像与采集到的印刷图像由RGB颜色空间转换到HSV颜色空间,并提取视觉上变化敏感的亮度分量V作为待检测对象;其次,将对比度受限的局部直方图均衡(CLAHE)与数学形态学相结合,来增强显现待检测图像中的缺陷;再次,使用连通域分析方法来获取缺陷的面积、周长、离心率、长宽比和圆形度等5种特征信息,并以此建立15个特征模型;最后,构建基于PNN的印刷缺陷识别神经网络,并在Matlab中实现对低对比度印刷缺陷的识别。结果 15个模型的平均耗时为475 ms,都控制在毫秒级别,满足了现代印刷缺陷检测对于实时性的要求。其中模型2的测试正确率为95%,能够识别污点等点缺陷,模型3和模型12的测试正确率为93%和93.3%,能够识别刮痕等线缺陷,模型5的测试正确率为93.1%,能够识别墨迹等面缺陷,且测试正确率高于基于BP神经网络的缺陷识别方法。结论 从缺陷检测的实时性和精确性上来讲,提出的方法能够对低对比度印刷缺陷进行实时和精确的检测。  相似文献   

6.
本文主要研究基于偏微分方程图像去噪增强。针对降质图像去噪增强问题,结合偏微分理论和图像去噪增强方法,改进P-M各向异性扩散模型,有效去噪并保留图像边缘信息。对于基于梯度场均衡化对比度增强的不足,结合偏微分和可调直方图均衡化,增强图像纹理并改善对比度,并客观质量评价处理后图像。  相似文献   

7.
研究了对完成计算机视觉任务有重要作用的视觉显著性检测,考虑到单纯依靠对比度计算进行显著性检测具有一定的局限性,提出了一种结合基元对比度与边界先验信息的显著性区域检测算法。该算法通过Mean-Shift分割构造图像基元结构,以图像基元为基础,利用图像颜色和亮度两种特征获得基元对比度显著图,再利用图像边界先验条件得到边界显著图;为了突出显著性目标,采用一种新的融合方式将以上检测结果进行融合,最后对显著图像进行多尺度增强操作,以获得更加高质量的显著性图。在国际公开数据集上的实验表明,该算法与现有的较成熟的方法相比,基本符合人眼的主观判断,具有较高的精度召回率。  相似文献   

8.
黄启宏  刘钊 《光电工程》2007,34(3):98-104
在纹理分类中采用谱直方图表示(SHR),每个图像窗表示一个包含滤波后图像直方图的特征向量,而直方图是图像谱表示的连接桥梁.在滤波器选择算法之前,结合每个图像分块和滤波器的独立谱表示和直方图,可以获得更加低层的局部特征.最后,时所有独立滤波器采用滤波器选择算法来得到所需的少量滤波器.为了保证分类的可靠性,选择高斯径向基函数(RBF)进行谱直方图表示,采用支持向量机(SVMs)作为分类函数.对本文方法和其它两种方法:Gabor滤波和独立成分分析(ICA)进行了纹理分类和脸部识别的比较实验.实验结果表明,本文方法具有更高的分类准确性,也证明了SVMs优秀的泛化能力.  相似文献   

9.
李海山  唐海艳  梁栋  韩军 《包装工程》2021,42(23):170-177
目的 提取样本图像颜色直方图特征对卷积神经网络进行训练,达到快速、高准确率检测图像颜色缺陷的目的.方法 将标准图像从RGB颜色空间转换至HSV颜色空间,通过改变图像H,S,V三分量值获取训练样本和测试样本;在HSV颜色空间中非均匀量化图像的颜色直方图,得到所有训练样本和测试样本的颜色直方图特征;利用样本图像颜色直方图特征训练卷积神经网络,然后对测试样本进行检测,研究检测的速度、准确率,并将该检测方法与逐像素、超像素、BP神经网络和支持向量机方法进行对比.结果 对于图片尺寸为512×512的彩色图像,卷积神经网络检测单幅图片的平均检测时间约为57.66 ms,训练样本图像为50000张时,卷积神经网络方法对10000张测试样本进行检测的准确率为99.77%.结论 卷积神经网络方法在保证高准确率的前提下大幅提高检测精度,对于印刷品色差缺陷在线检测具有良好的应用价值.  相似文献   

10.
图像描述方法中在信息输入时只将图像作为输入,在端到端训练过程中,内部参数变化难以获取,很有可能造成错误.为进一步减小图像描述的不确定性,在图像描述任务中应用知识增强方法,即在输入端输入图像中的主题信息,将图像描述的范围确定化.提出了一种新的双通道图像描述架构,该架构包括主题通道与图像通道两部分,主题通道提取语义信息,并将其作为主题信息对图像信息进行知识增强;图像通道实现经典图像描述任务功能.两个通道都由极快速区域神经网络进行编码提取特征,采用注意力机制进行特征筛选,由长短期记忆网络进行解码预测信息.最后再使用一个长短期记忆网络综合两个通道的信息,实现主体通道对图像通道的知识增强并生成描述.该方法在数据集Flickr与MS COCO上测试,与一般的图像描述方法相比准确率获得了提高.  相似文献   

11.
A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.  相似文献   

12.
Permeable crystalline materialcan permeate into pores and cracks of concrete and catalyze the reaction between Ca(OH) 2and unhydrated cement to generate a great quantity needle non-soluble crystals, which can stop up the pores and cracks of concrete, and increase the impermeability of concrete. This paper reported the results of a study conducted to evaluate steel reinforcement corrosion of concrete specimens uncoated and coated with permeable crystalline material as well as mixed with the permeable crystalline material. The properties evaluated for corrosion test were water impermeability, water absorption, compressive strength and potential. The results of water impermeability, water absorption, compressive strength clearly showed that the permeable crystalline material could prohibit water, any soluble salts and moisture from penetrating the concrete to cause corrosion, leaking, and other problems, and it did increase the compressive strength, which was favorable for protection of corrosion of reinforcing steel. Moreover, it was concluded from the potential-time curve that the steel reinforcement of uncoated specimen was in the state of activation whereas that of other specimens coated and mixed with the permeable crystalline material was in the state of inactivation. Above all, it was indicated that the permeable crystalline materialis very effective to protect the steel reinforcement of concrete from corrosion.  相似文献   

13.
In this paper, the principle of spurting take off lacquer were introduced; and with orthogonal method the unsaturate polyester was prepared ;it was easy to peel airplane paint layer off with this material and equipment.  相似文献   

14.
Quality Study of Honeycomb Core Shaping Without Wax Stabilization   总被引:1,自引:0,他引:1  
Sandwich panels utilizing honeycomb cores result in lightweight, high-strength units that are very rigid. Indeed, they give honeycomb panels the best strength-to-weight ratio of any construction type available. Conventionally, the wax is poured into the cell of the core to strengthen the structure and prevent the core from being crushed during milling. Much time and labor is required to wax, mill, and clean the cores. In this study, the process of pouring wax into the core was skipped. In other words, the cutter directly milled the core. Experiments showed that the compressive strength of the core produced without wax stabilization was only 3% lower than that of cores produced using the traditional method. In addition, the drum peel strengths of cores produced without wax stabilization were 38.4% higher than cores produced using the traditional method, in which residual wax seriously polluted the adhesive. It was also found that eliminating the wax process can reduce costs.  相似文献   

15.
The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……  相似文献   

16.
Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.  相似文献   

17.
We studied a combined effect of the cryoprotectants both of lipid and carbohydrate origin at the presence of DMSO or without it on cell viability and the RNA synthesis in the embryonic mollusc and echinoderm cell cultures obtained at different developmental stages. Cryoprotective properties of exogenous lipids correlated with their thermotropic behavior. Lipid extracts from marine hydrobiontes, which thermal transitions are characterized by relatively small part of calorimetric thermogram area lying at temperatures above 0 °C (6–18%), were found to possess a considerable cryoprotective activity. The results are discussed in relation to the prediction of the cryoprotective activity of lipid extracts for marine animal cells. In addition, it was found that marine invertebrate cells can be cryopreserved without DMSO at the presence of trehalose and lipid extracts of some marine hydrobiontes.  相似文献   

18.
Polylactic acid (PLA) is one of the most widely used open source fused filament fabrication materials due to its ease of extrusion, biodegradability, and mechanical strength. The mechanical strength of PLA largely depends on the proper growth of its semi-crystalline structure, which can be severely impaired by a low rate of crystallization, particularly in open source printers. This can be further aggravated by the non-uniform thermal distribution of heat that causes improper curing among the extruded beads of the printing material. As a result, PLA printed on open source printers does not achieve the best mechanical properties. This research, for the first time, proposes an additive-free solution implemented through a detailed set of experimentation to improve the curing rate through in-process temperature variations to cure the joints among the beads. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR) spectroscopy is used to confirm the improvements in the bead joints. This work is conducted in two phases of experiments. In the first phase, a full factorial ANOVA is used to investigate various process parameters and the important variables are used in the second phase to print test specimens in four different sets.  相似文献   

19.
Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability.  相似文献   

20.
ABSTRACT

The production of iron in Biscay (Basque Country, Spain) has been a hallmark of this territory of the North of the Iberian Peninsula throughout its history. The Archaeology team of the Basque Country Mining Museum has spent 13 years, so far, studying the origins of this activity through the evidences left at the old pre-hydraulic iron production workshops known as mountainside ironworks (ferrerías de monte) or haizeolak. It has catalogued 170 archaeometallurgical sites of this type in Biscay, and the archeological excavation of some of them has led to the knowledge of the different stages of the production process that took place in these workshops. The team has also experimentally reproduced the work carried out in a mountainside ironworks from the High Middle Ages, and it has currently started the characterization process of this type of activity through the study of the collected materials.  相似文献   

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