Abstract: In order to precisely detect skew of fabric images, we propose a novel skew detection scheme based on wavelet transform and projection profile analysis. Firstly, the test image is decomposed by wavelet transform, and the weft boundary is generated by binarizing the horizontal sub-band coefficients matrix according to setting optimal threshold. Then morphological method is adopted to reduce serrated points around weft boundary. In the end, a projection profile is computed at each angle, and the angle that maximizes a criterion function is regarded as the skew angle. Experimental results show that the skew angles detected by the proposed detection algorithm are of higher accuracy.

Key words: fabric , skew , wavelet transform , morphological method , erosive operation , projection profile analysis