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21.
In full reference image quality assessment (IQA), the images without distortion are usually employed as reference, while the structures in both reference images and distorted images are ignored and all pixels are equally treated. In addition, the role of human visual system (HVS) is not taken account into subjective IQA metric. In this paper, a weighted full-reference image quality metric is proposed, where a weight imposed on each pixel indicates its importance in IQA. Furthermore, the weights can be estimated via visual saliency computation, which can approximate the subjective IQA via exploiting the HVS. In the experiments, the proposed metric is compared with several objective IQA metrics on LIVE release 2 and TID 2008 database. The results demonstrate that SROCC and PLCC of the proposed metric are 0.9647 and 0.9721, respectively,which are higher than other methods and it only takes 427.5 s, which is lower than that of most other methods. 相似文献
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Dr. Jiong Zhou Dr. Guocan Yu Yang Li Jie Shen Mengbin Wang Dr. Zhengtao Li Dr. Peifa Wei Prof. Dr. Jianbin Tang Prof. Dr. Feihe Huang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(63):14447-14453
Cyanide is extremely hazardous to living organisms and the environment. Owing to its wide range of applications and high toxicity, the development of functional materials for cyanide detection and sensing is highly desirable. Host–guest complexation between bis(p-phenylene)-34-crown-10 H and N-methylacridinium salt G remarkably decreases the detection limit for cyanide anions compared with that of the guest itself. The [2]pseudorotaxane selectively recognizes the cyanide anion with high optical sensitivity as a result of the nucleophilic addition of the cyanide anion at the 9-position of G . The host–guest complexation is further incorporated into supramolecular materials for the visual detection of cyanide anions, especially the detection of cellular cyanide excretion with a detection limit of 0.6 μm . This supramolecular method provides an extremely distinct strategy for the visual detection of cyanide anions. 相似文献
24.
This paper presents a novel image segmentation algorithm driven by human visual system (HVS) properties. Segmentation quality metrics, based on perceptual properties of HVS with respect to segmentation, are integrated into an energy function. The energy function encodes the HVS properties from both region-based and boundary-based perspectives, where the just-noticeable difference (JND) model is employed when calculating the difference between the image contents. Extensive experiments are carried out to compare the performances of three variations of the presented algorithm and several representative segmentation and clustering algorithms available in the literature. The results show superior performance of our approach. 相似文献
25.
Abstract-Brain-computer interface (BCI) can help the deformity person finish some basic activities. In this paper, we concern some critical aspects of SSVEP based BCI, including stimulator selection, method of SSVEP extracting in a short time, stimulating frequency selection, and signal electrode selection. The conclusion is that the stimulator type should be based on the complexity of the BCI system, the method based on wavelet analysis is more valid than the power spectrum method in extracting the SSVEP in a short period, and the selections of stimulating frequency and electrode are important in designing a BCI system. These contents are meaningful for implementing a real SSVEP-based BCI. 相似文献
26.
局部方差在图像质量评价中的应用 总被引:4,自引:0,他引:4
将灰度图像的局部方差分布(QLS)作为表征图像结构信息的一个重要特征,对局部方差分布矩阵进行奇异值分解,计算得到相应的奇异值特征向量;通过计算降质图像与原参考图像局部方差矩阵奇异值特征向量的夹角大小度量两图像的结构相似度,实现了对降质图像的质量评价。实验结果表明:局部方差分布更能突出图像的结构特征,评价结果优于传统的均方误差(MSE)、峰值信噪比(PSNR)、结构相似度(SSIM)以及直接评价图像像素分布的奇异值分析(SVD)等方法,与人眼视觉感知效果的一致性较好。 相似文献
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In this paper, we propose a novel image recompression frame?work and image quality assessment (IQA) method to efficient?ly recompress Internet images. With this framework image size is significantly re... 相似文献
29.
为了实现对假手的智能控制,文中提出一种基于语音控制的设计方案。语音识别系统接收发音人的语音命令,并将语音命令转换成主控系统能识别的数字信号。主控系统接收数字信号,同时根据命令向指关节发送数据驱动指关节伺服电机正向或反向转动。指关节转动的角度被指关节电位器转换成相应的电信号。主控系统将角度电信号转换成数字信号,并将此数字信号和命令初始数据比较,从而发出修正命令数据,驱动指关节伺服电机走到指定的位置。在抓握不同物品时,本系统中在每个指尖安装有高灵敏度的压力传感器以检测指尖的受力,确保物品既被抓牢又不被压坏,从而实现对假手的智能控制。 相似文献
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