It has been considered as a great challenge to identify the blending ratio of polyester/cotton yarn in the field of textile industry. A new digital cross‐sectional image processing method based on geometrical shape analysis is proposed to improve the measurement accuracy of polyester/cotton blend ratio. A self‐developed microscope image capturing system is established to digitalise the cross‐sectional images of polyester/cotton blended yarn. One set of image preprocessing algorithm is developed to conduct greyscale inversion, median filtering denoising and binarisation. The specially designed edge detection algorithm is used to identify the continuous profile of fibres. Finally, the roundness value of the cross‐sectional fibre is calculated based on the proposed roundness algorithm, it can be used to identify the polyester/cotton fibres and calculate the blending ratio of them. Our experimental results show that the new digital analysis method proposed in this paper is feasible for the measurement of polyester/cotton blended ratio; therefore, it has a good application prospect in the field of textile quality control, including the development of new equipment, methods and standards.

中文翻译：

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断面图像分析法测定涤棉纱混纺比的研究

在纺织工业领域，确定涤棉纱的混纺比一直被认为是一个巨大的挑战。提出了一种基于几何形状分析的数字截面图像处理新方法，以提高涤棉混纺比的测量精度。建立了自主开发的显微镜图像捕捉系统，将涤棉混纺纱线的横截面图像数字化。开发了一套图像预处理算法来进行灰度反演、中值滤波去噪和二值化。专门设计的边缘检测算法用于识别纤维的连续轮廓。最后，根据提出的圆度算法计算横截面纤维的圆度值，它可用于识别涤棉纤维并计算它们的混纺比。我们的实验结果表明，本文提出的新的数字分析方法对于涤棉混纺比的测量是可行的；因此，它在纺织品质量控制领域，包括新设备、方法和标准的开发方面具有良好的应用前景。