基于双面成像的色织物密度自动测量技术

探究了色织物纱线密度自动测量的方法,通过一套实验室自行开发的双面图像采集系统采集色织物的正反双面图像,利用Radon变换和仿射变换对采集得到的双面图像进行对位和匹配,通过2种不同融合算法将双面图像进行融合,借助快速傅里叶变换技术(FFT)提取融合图像中对应周期性结构的特征频率点,利用快速傅里叶反变换技术(IFFT)对特征频率点进行重构,最终测得织物密度。分析了色织物单面图像和双面融合图像的傅里叶频谱图,发现单面图像的纹理分布是片段式的,对应的频谱是分散的,而双面融合图像的频谱能量集中在水平或垂直方向,对应的纱线频率点容易提取。试验结果表明:基于双面成像测得纱线密度与密度镜法测得结果相比,最大误差为1.96%,平均误差为0.86%,该方法可以提高色织物纱线密度测量的准确性。

Automatic density measurement of yarn dyed woven fabrics based on dual-side scanning

Automatic density measurement of yarn dyed woven fabrics was discussed. The dual-side images were captured using the lab-used dual-side image acquisition system. Radon transform and affine transform were utilized to align and match the dual-side images. The dual-side images were fused based on two kinds of image fusion methods, and the frequency points corresponding to the periodical structure could be extracted with the aid of Fast Fourier Transform (FFT) technique. Meanwhile, the reconstructed images could be obtained based on inverse Fast Fourier Transform (IFFT) technique, and the yarn density could be measured. The power spectrums of one-side image and dual-side fused image were analyzed. It is found that the texture of one-side image is not continuously connected and the frequency spectrum is scattered. However, the spectrum energy of fuses image focused on the horizontal or vertical direction so that the corresponding frequency points could be easily extracted. The test result shows that the maximum deviation between our method and the density meter based method is 1.96%, and the average deviation is 0.86%. It is considered that the method could improve the accuracy of density measurement of yarn dyed woven fabrics.