One of the most salient examples of the above mentioned In this study, the viscose roving was used as the raw material. Then using the ring machine, 25 samples of different count and twist were spun. For each sample 9 bobbins were provided out of which 4 were tested in premier machine and their hairness including the number of fibres in different longitudinal domains was calculated along with the premier hairness parameter. Later the remaining 4 bobbins were unwound inside the co-unwinding machine, where the direction of yarn passage prevents the yarns from spreading, and the separated fibres were placed on the slide soaked with slide oil and then the collections were scanned with scanners .The scanned photos were initially read using Mathlab image processing and subsequently by binary rendition of the images, selection of appropriate shareholding ,and the lessening of the fibre thickness into one pixel the number and the length of the fibres were calculated .The results indicated that the increase in twist accompanies the decrease in hainess and fly production since the side force which is the product of the increase in twist grows in strength resulting in decline in possibility of fly distribution. In addition, the effect of count on hairness and the amount of the fly produced was investigated and according to the findings, the decrease in yarn count equals the thicker yar since the thicker yarns contain more fibres and the possibility of fibre being spread out of the thicker yarn increases , furthermore, with the equal twist which exerts a steady force to the yarn , each fibre becomes less susceptible to the steady force originating from twist , consequently, fibres easily separate from the yarn. In this study the correlation between Premiere machine hairness parameter and the length of the fly produced was calculated and reported 0.947 and 0.951 respectively. Apart from the above mentioned points, using the count and the length of the fly produced calculated through the image processing, the weight of the fly produced was calculated and through dividing the fly produced in grams by the yarn used in kilogram a parameter was yielded which was previously reached by the excessive weight of the raw material and separating its fly. The outstanding advantages of the image processing procedure in comparison with the previous methods could best be characterized as less costly and more time saving.