A method for assessing a quality of an elongate textile body comprising the steps of running the elongate textile body past at least one sensor head (12, 18, 24, 30; 44), determining, by means of the sensor head (12, 18, 24, 30; 44), a set of samples B m = (B 1m ... B Km ) of body parameters of the textile body with K > 1 by repetitively carrying out online measurements, wherein said body parameters include a color parameter (Cp) descriptive of at least one color component, in particular several color components, of the textile body , wherein m = 1 ... M with M > 1 using the samples B m for assessing the quality of a section of the elongate textile body, characterized in that the quality of the section is assessed by at least one of A) assessing a variability of the color parameter (Cp) in said section and issuing an alert and/or removing at least part of said section if the variability is smaller than a desired first variability level, wherein the variability is a monotonously increasing function of a variance, of a standard deviation, or of a percentile range of the at least one color component, and/or B) comparing the color parameter (Cp) in said section against a secondary color (Cd) indicative of the color of a dye the elongate textile body is to be dyed with or of a secondary color if the textile body is a fancy yarn. running the elongate textile body past at least one sensor head (12, 18, 24, 30; 44), determining, by means of the sensor head (12, 18, 24, 30; 44), a set of samples B m = (B 1m ... B Km ) of body parameters of the textile body with K > 1 by repetitively carrying out online measurements, wherein said body parameters include a color parameter (Cp) descriptive of at least one color component, in particular several color components, of the textile body , wherein m = 1 ... M with M > 1 using the samples B m for assessing the quality of a section of the elongate textile body, characterized in that the quality of the section is assessed by at least one of A) assessing a variability of the color parameter (Cp) in said section and issuing an alert and/or removing at least part of said section if the variability is smaller than a desired first variability level, wherein the variability is a monotonously increasing function of a variance, of a standard deviation, or of a percentile range of the at least one color component, and/or B) comparing the color parameter (Cp) in said section against a secondary color (Cd) indicative of the color of a dye the elongate textile body is to be dyed with or of a secondary color if the textile body is a fancy yarn. A) assessing a variability of the color parameter (Cp) in said section and issuing an alert and/or removing at least part of said section if the variability is smaller than a desired first variability level, wherein the variability is a monotonously increasing function of a variance, of a standard deviation, or of a percentile range of the at least one color component, and/or B) comparing the color parameter (Cp) in said section against a secondary color (Cd) indicative of the color of a dye the elongate textile body is to be dyed with or of a secondary color if the textile body is a fancy yarn. <EOS>