Objective Assessment of Pilling of Nonwoven Fabrics Using the Two Dimensional Discrete Wavelet Transform

Abstract- Fabric pilling is a serious problem for the apparel industry, causing an unsightly appearance and premature wear. Woolen products are particularly prone to pilling. Recently, a process for production of woolen nonwoven ap-parel fabrics has been commercialized in Australia, and may lead to new markets for Australian wool. However, the suc-cess of such nonwoven fabrics will partly rely on their pro-pensity to pill. A key element in the control of fabric pilling is the evaluation of resistance to pilling by testing. Resis-tance to pilling is normally tested in the laboratory by processes that simulate accelerated wear, followed by a ma-nual assessment of the degree of pilling by an expert based on a visual comparison of the sample to a set of test images. To bring more objectivity into the pilling rating process, a number of automated systems based on image analysis have been developed. The authors previously proposed a new me-thod of image analysis based on the two-dimensional discrete wavelet transform to objectively measure the pilling intensi-ty for woven fabrics. This paper presents preliminary work in extending this method to nonwoven fabrics