Formation of digital yarn black board using sequence images

This paper presents a new method for building a digital yarn black board (DYBB) with the yarn diameter data obtained from processing sequential yarn images. An image acquisition and processing system, mainly consisting of a video camera, a single-chip micro-computer and a stepper motor, was set up to capture sequence images of a moving yarn and extract yarn diameter data after the image threshold and morphological opening operation. Then, the diameter data of the yarn was used to construct the DYBB by redrawing all the scans in white on a black plane once they were aligned at the centers. The DYBB provides functions, such as local data amplification, fast focusing, phase adjustment and space adjustment, for more intuitive and convenient evaluation of yarn evenness.