Measuring Structural Parameters of Knitted Fabrics by Digital Image Processing Techniques

In the knitting industry the measurements of the stitchdensity and the stitch length are usually done manuallywhich may lead to fatigue of the eyes,subjective ideasbrought into the test results and low precision.The mostcommon method of measuring stitchlengthin static state isby raveling the stitch.Damage tothe fabricis unavoidable.Therefore it is necessary to find a scientific and feasibletrial balloon.Digital Image Processing Techniques are nowbroadly applied in many scientific aspects inc…

Measuring Structural Parameters of Knitted Fabrics by Digital Image Processing Techniques

In the knitting industry the measurements of the stitch density and the stitch length are usually done manually, which may lead to lower efficiency and less definition and also bring subjective ideas into the test results. In order to improve the effect we can measure with Digital Image Processing Techniques. A piece of sample is scanned into computer and changed into a digital image, which is processed with media filtering. To acquire the power spectrum, the image in the spatial domain is converted into the frequency domain. Picking up the characteristic points describing the stitch density and the stitch length separately in the power spectra and reconstructing them, the values of the stitch density and the stitch length could be calculated. When measuring the stitch length, we should establish a geometric model of the stitch based en the digital image processing, which provides a method to transform the stitch length in the two-dimensien space into the three-dimensien space and to measure the value of the stitch length more accurately. This method also provides a new way to measure the stitch length without damaging the fabric.