共查询到19条相似文献,搜索用时 578 毫秒
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This paper describes a machine vision system for the detection of weft‐knitted fabric defects based on an adaptive pulse‐coupled neural network (PCNN) and Ridgelet transform. In order to classify defects according to their different texture features, two methods are implemented: an improved PCNN method to segment the defects such as hole and dropped stitch from background image and a Ridgelet transform method based on wavelet analysis to identify the defect such as course mark. In implementing the PCNN model, necessary parameters of PCNN model such as linking coefficient, connection weight, and iteration number are automatically calculated in accordance with the spatial distance of neurons, mean, and variance value of whole image, and the cross‐entropy criterion. The function of Ridgelet transform is to identify the straight line marks and fit the regression equation for simulating the course mark in the image. The Ridgelet transform model can be simplified as the combination of Radon and wavelet transforms. The parameters of detected line are acquired by wavelet analysis in Fourier semicircle region. The experiment materials were several plain and interlocked weft‐knitted fabrics with hole, dropped stitch, and course mark defects. The fabric images were captured by an area‐scan camera with a resolution of 600 × 800 pixels, and signal processing was controlled by a digital signal processing multiprocessor on the inspection machine. The validation tests proved that the system performed well. 相似文献
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Basic morphological operations such as the erosion, dilation, opening, and closing often fail to detect various types of defects that may be present in woven fabric, mainly because of the heuristic selection of structuring element needed for these operations. In this paper, an artificial neural network (ANN) is utilized for the selection of structuring element, where ANN is trained by two pre‐assigned normalized numbers related to the warp and weft counts of the test fabric. The test gray fabric image is pre‐processed to remove noise and the interlaced grating structure of weft and warp and then converted to a binary image by thresholding. An intensity threshold value of the processed fabric image and the dimension of a sliding window needed for correlation operation are obtained from the trained ANN. Defects are detected after morphological reconstruction of the processed binary fabric image, where an ANN trained structuring element is used. The technique is tested on 317 samples for eight different types of defects in three types of plain woven fabrics from TILDA database and 92.8% success of detection is achieved. 相似文献
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一种新的静态测试线圈长度的方法 总被引:1,自引:1,他引:1
静态测试纬编针织物的线圈长度对降低成本、提高生产效率是很有必要的。用数字图像处理技术将摄入的图像进行灰度变换、滤波去噪,再用二维傅里叶变换技术提取线圈长度的特征,推导出线圈长度在二维空间与三维空间内的关系转换式,进而求得纬编针织物的线圈长度。这为非破坏性测试线圈长度提供了一种新的方法。 相似文献
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为了探讨Dornier喷气织机上纬纱线密度与纬纱飞行状态之间的关系,为优化引纬工艺提供技术基础。本文以Dornier AWV8/S型喷气织机为实验平台,通过高速摄像系统对纬纱在筘槽中实际引纬飞行状态进行了拍摄记录,使用Image pro-plus 6.20专业图像分析软件对所拍摄的纬纱运动过程图像进行了分析,得出了不同线密度纬纱飞行过程的平均速度、加速度和垂直波动距离。结果表明,在实验条件下,相同引纬条件的同种材质的纱线速度和加速度随着纱线线密度的增大而增大,纱线线密度越大,纱线的飞行状态越稳定。因此,要在Dornier喷气织机上获得速度快、波动小的运动状态,首选10tex棉纱条件。 相似文献
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为实现色织物疵点的有效检测,提出一种应用上下文视觉显著性的疵点检测方法。根据上下文视觉显著性的原则,将织物图像分为大小相同的图像块;然后针对每个图像块,选取K个与其最相似的图像块计算与该图像块的差异值之和,用该差异值之和表示该图像块中心像素的显著性;从而生成一幅视觉显著性图;最后对显著性图进行阈值分割,得到色织物疵点的检测结果。为验证该算法的有效性,将带有纬缩、破洞和跳花等区域性疵点的素色、条纹和格子色织物图像作为样本进行检测。结果表明:该方法可较好地抑制不同种类织物的纹理背景,突出疵点区域,实现疵点的有效检测,该方法在色织物疵点检测上具有一定的可行性。 相似文献
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针对当前算法对种类繁多瑕疵,尤其是经纬向瑕疵适应差问题,提出一种应用局部纹理特征的无监督织物瑕疵检测算法。这种算法采用无监督检测方案,检测过程中不需要参考样本。在检测过程中,首先根据瑕疵稀少性特点,直接从整体织物图像中获取表征局部织物纹理的局部二值模式直方图特征;然后利用机织物经纬交织特点对局部织物图像沿经纬向投影,并在此基础上提取特征;最后计算所提取特征的瑕疵异常图,并对其进行权重方式融合后实施阈值分割,实现瑕疵检测。实验结果表明,所提出的投影特征能有效表征局部织物纹理,与局部二值模式特征结合使用能有效检测织物瑕疵。 相似文献
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为研究数码混色纱纬编针织物的外观色彩及纹影的模拟方法,利用图像处理技术对采集的图像进行平滑去噪,得到剔除细节的模糊图像,在Lab 空间下运用彩色图像硬聚类算法对平滑后的图像进行聚类分割,得到混色纱主体图像,获取其左右的边界和中心线信息;然后在经典的Pierce 线圈模型的基础上,利用混色纱主体图像的廓线信息完成由纱线到线圈圈弧和圈柱的映射;最终根据不同组织的圈弧和圈柱的覆盖关系,得到基本纬编针织物组织。结果表明,提出的纱线映射线圈算法,通过织物组织结构及密度可模拟混色纱纬编织物的混色色彩及外观纹影。 相似文献
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针对纬编光坯针织物中存在的不同类型疵点,使用Photoshop和MATLAB软件对其疵点的扫描图像进行预处理,以检测传统的织物疵点。然后通过对色点、玷污、破洞、粗纱等几种疵点图像进行分析和处理,最终得出常见的针织物疵点图像的特征量提取方法。实验结果表明,对于不同类型的疵点,可通过不同的处理方法来获得较佳的结果。 相似文献
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意达K88型剑杆织机织疵成因与减少措施探讨 总被引:1,自引:0,他引:1
K88型剑杆织机常见的织疵有断经、纬缩、停车痕等。文章对各类织疵的成因进行了分析,并提出了实用、有效的解决措施,为企业提高产品质量提供参考。 相似文献