The Research Of Mesh Fabric Fast Detection Based On Image Processing

In the process of rapid development of screen printing,the quality of mesh fabric has become the focus of attention in the industry.However,the method of artificial detection is still dominant at present,which exposed the low efficiency,and the test results are not stable,limiting the production and development of enterprises.In this paper,digital image processing technology is used for mesh fabric detection,the use of digital image acquisition and processing equipment combined with advanced digital image processing algorithms for mesh fabric parameters frapid detection,the parameters such as the warp and weft density,the warp and weft straightness(tilt angle)and the defects of mesh fabric can be detected rapidly.Firstly,in order to filter out the image noise and improve the contrast image,the median filter and histogram equalization algorithm is used to preprocess the image of the mesh fabric image,which is ready for subsequent image processing.Aiming at the problem of the tilt of the mesh fabric image,the Hough transform algorithm is used to detect the tilt angle of the warp and weft yarns of the mesh fabric,and the fast tilt correction of the mesh fabric image is realized by the image rotation,reducing the error of subsequent mesh fabric detection.Secondly,in this paper the density detection algorithm based on gray scale projection,the density detection algorithm based on Fourier transform and the density detection algorithm based on wavelet transform is studied,and a simple operation interface is designed according to analyzing the experiment results,which can be used to detect the mesh fabric.The pre-processed image is subjected to Fourier transform,and the pre-judgment is based on the first peak point coordinate information of the spectrum.When the first peak coordinate value is larger than the set value,the warp and weft density can be calculated by the formula of density detection algorithm of Fourier transform.When the coordinate value of the first peak is smaller than the set value,the warp and weft density can be calculated by the formula of density detection algorithm of the gray projection algorithm.In this way,the precision of the warp and weft density of mesh fabric is greatly improved,and the scope of application is also broader.Thirdly,this paper presents a mesh fabric defect detection algorithm based on Fourier transform.The pre-processed mesh fabric image is converted into frequency domain information by Fourier transform.The background spectrum is filtered by the frequency band Butterworth low-pass filter,then the improved iterative threshold segmentation method is used to segment the defect after the Fourier inverse transform.Finally,as an extension of the mesh fabric detection algorithm,this paper designs the module structure,detection process and simple software system for the mesh fabric detection by using Visual Studio software to compile programming through C# language and MATLAB.On the basis of digital image processing,this topic realizes the rapid and effective mesh fabric detection of the tilt angle,the density of warp and weft yarns,the defects of the mesh fabric,which improves the speed and accuracy of the screen detection.It has certain theoretical significance for the application of digital image processing in the automatic detection of the mesh cloth,and has a good application prospect in the production.