An analysis of the variances of a set of colored textile patches, sampled from the Scott-Munsell textile set, relative to their mean values, demonstrated several systematic trends. Overall, the amount of variance in the data as expressed by the shape and the orientation of the ellipsoids was found to be greatest in the L direction. Additionally, the shape and orientation of the ellipsoids was determined to be largely a function of chroma and lightness. No overall correlation was found between the distribution of the ellipsoidal volume and their hue or chroma. However, with exceptions, ellipsoidal volume peaked in patches with intermediate values of L*. It was shown that the variance in the value of L* is inversely proportional to the concentration of the colorant(s) in the sample. In addition, as the chroma of a sample increased, an increase was identified between the amount by which the concentration of colorant changed relative to the amount by which the value of L* changed. Last, significant errors in the calculation of colorimetric values resulted from the use of a scanner of low quality, an inadequate method of colorimetric characterization, and the use of a spectrally selective gray scale in the gray balancing process. Together, these produced distortion in the mean values, the orientation, and the shape of the ellipsoids.
Library of Congress Subject Headings
Colorimetric analysis; Spectrophotometry; Fourier analysis; Textile fibers--Identification; Dyes and dyeing--Textile fibers--Identification
Department, Program, or Center
Chester F. Carlson Center for Imaging Science (COS)
Ansell, Seth, "A Study of ellipsoidal variance as a function of mean CIELAB values in a textile data set" (1995). Thesis. Rochester Institute of Technology. Accessed from
RIT – Main Campus