In this paper changes in the appearance of 100% cotton ring spun yarns due to several yarn-to-yarn abrasion cycles before rupture are characterized. Different pictorial indexes for four different yarn counts are evaluated. The process of abraded yarns is defined by image processing techniques. The comparison between the indexes found that the weight loss of yarns at each step is performed using linear regression analysis to introduce the most appropriate index for quantifying the yarns’ abrasion. The mean value of diameter index which is related to the changes in yarn core shows the highest correlation with weight loss. This method enables studying the yarn-to-yarn abrasion behavior before rupture more accurately and rapidly for quality control purposes.