The gradient image is always sensitive to noise in image detail enhancement. To overcome this shortage, an improved detail enhancement algorithm based on difference curvature and contrast field is proposed. F...The gradient image is always sensitive to noise in image detail enhancement. To overcome this shortage, an improved detail enhancement algorithm based on difference curvature and contrast field is proposed. Firstly, the difference curvature is utilized to determine the amplification coefficient instead of the gradient. This new amplification function of the difference curvature takes more neighboring points into account, it is therefore not sensitive to noise. Secondly, the contrast field is nonlinearly amplified according to the new amplification coefficient. And then, with the enhanced contrast field, we construct the energy functional. Finally, the enhanced image is reconstructed by the variational method. Experimental results of standard testing image and industrial X-ray image show that the proposed algorithm can perform well on increasing contrast and sharpening edges of images while suppressing noise at the same time.展开更多
In this paper,the mean curvature flow of complete submanifolds in Euclidean space with convex Gauss image and bounded curvature is studied.The confinable property of the Gauss image under the mean curvature flow is pr...In this paper,the mean curvature flow of complete submanifolds in Euclidean space with convex Gauss image and bounded curvature is studied.The confinable property of the Gauss image under the mean curvature flow is proved,which in turn helps one to obtain the curvature estimates.Then the author proves a long time existence result.The asymptotic behavior of these solutions when t→∞is also studied.展开更多
During the 3D shape measurement,there are noises in the images that are obtained by the capture system.The traditional method,Fourier transform profilometry(FTP) technique,improves the accuracy only by the filtering m...During the 3D shape measurement,there are noises in the images that are obtained by the capture system.The traditional method,Fourier transform profilometry(FTP) technique,improves the accuracy only by the filtering method in the frequency domain.In this paper,the curve fitting method is used for the light field distribution calculation before the filtering process applied in the frequency domain by choosing a suitable filter window,and then the higher quality of the basic frequency component signal is got.This method can avoid the frequency overlapping caused by the noise,so the improvement of the measuring accuracy of FTP is realized.展开更多
基金National Natural Science Foundation of China(No.61271357)International S&T Cooperation Program of Shanxi Province(No.2013081035)
文摘The gradient image is always sensitive to noise in image detail enhancement. To overcome this shortage, an improved detail enhancement algorithm based on difference curvature and contrast field is proposed. Firstly, the difference curvature is utilized to determine the amplification coefficient instead of the gradient. This new amplification function of the difference curvature takes more neighboring points into account, it is therefore not sensitive to noise. Secondly, the contrast field is nonlinearly amplified according to the new amplification coefficient. And then, with the enhanced contrast field, we construct the energy functional. Finally, the enhanced image is reconstructed by the variational method. Experimental results of standard testing image and industrial X-ray image show that the proposed algorithm can perform well on increasing contrast and sharpening edges of images while suppressing noise at the same time.
基金the National Natural Science Foundation of China(No.10531090).
文摘In this paper,the mean curvature flow of complete submanifolds in Euclidean space with convex Gauss image and bounded curvature is studied.The confinable property of the Gauss image under the mean curvature flow is proved,which in turn helps one to obtain the curvature estimates.Then the author proves a long time existence result.The asymptotic behavior of these solutions when t→∞is also studied.
基金supported by the Natural Science Foundation of Tianjin Municipal Science and Technology Commission (No. 06YFJMC15600)
文摘During the 3D shape measurement,there are noises in the images that are obtained by the capture system.The traditional method,Fourier transform profilometry(FTP) technique,improves the accuracy only by the filtering method in the frequency domain.In this paper,the curve fitting method is used for the light field distribution calculation before the filtering process applied in the frequency domain by choosing a suitable filter window,and then the higher quality of the basic frequency component signal is got.This method can avoid the frequency overlapping caused by the noise,so the improvement of the measuring accuracy of FTP is realized.
