Warp and weft spacing and its coefficient of variation affect the physical properties of fabrics such as fabric hand, frictional and mechanical properties. In this paper the weft and warp spacing and its coefficient of variation for plain weave is calculated using Fourier transforms. Different methods have been used in this work including autocorrelation function. First, two dimensional power spectrum of the gray level image of the fabric was estimated using Fourier transforms. Then, inverse Fourier transform was used to calculate the two dimensional autocorrelation function. Finally, from autocorrelation function and autospectral density the periodicity of the warps and the wefts were calculated. The results from ACF and microscopic methods yielded a significant correlation factor (r2). Thus image processing coupled with application of fourier transforms can be considered as a new method and a good substitute for the microscopic method.

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