Paramerism and reliable parameric correction

Abstract

In this article, the parameric decomposition method is considered as a technique for batch correction using three process primaries. It is proved that the parameric decomposition technique using optimal process primaries is a suitable method for reliable batch correction. Besides, the evaluation of parameric correction error for estimation of metamerism index is discussed. The creation of optimal spectral dataset to derive the appropriate process primaries is presented and the estimation of optimal statistical colorants for color reproduction of paint system is also developed. A set of pigments as primaries is used to generate three sets of batches using Kubelka-Munk theory; each set includes 10,000 paramer samples. Three sets of batches are generated to have different distributions around the match sample of target. The performance of process primaries derived from the Munsell dataset is compared with the optimal estimated statistical colorants for reliable parameric correction. To achieve greater success in estimation of appropriate metamerism index and make the estimated index more reliable, the statistical colorants used for parameric correction should be achieved from the spectral dataset generated by real primaries being used for matching of the target color. The outcome of parameric correction for pairs having miscellaneous mismatches is investigated to find out if it is sensible to just consider mismatch threshold for pairs being corrected. Finally, the conceptual subject of paramerism is developed to verify which spectral essence could be called as the paramer of an individual target color being matched.

Illuminant metamerism potentiality of metameric pairs

“…Since the colour positions of a metameric pair in Figure 1a coincide under the reference illuminant, the term is equal to for a purely metameric pair. The colour positions of a parameric pair can be virtually corrected by an appropriate parameric correction method [13,14] to obtain a perfect virtual match under the reference illuminant.…”

“…In practical colour reproduction where parameric pairs are available, spectral adjustment of the batch sample could be performed using an appropriate spectral parameric correction method [13,14], in order to satisfy the assumption of , i.e. .…”

“…As claimed in the paper by Li and Berns [13], neither the Matrix R nor additive or multiplicative correction methods are the suitable parameric correction techniques for evaluating metamerism. Hence, the proposed principal component analysis (PCA) method [14] was used to spectrally correct the 10 parameric printed samples in order to obtain zero colour difference under the reference illuminant D65. Therefore, is valid for calculating the IMPs of the corrected samples, each of them associated with the target colour.…”

“…for a purely metameric pair. The colour positions of a parameric pair can be virtually corrected by an appropriate parameric correction method [13,14] to obtain a perfect virtual match under the reference illuminant. Equation 1 can be rewritten for a standard sample and its match to obtain Eqns 15 and 16, which predict the approximation of corresponding colorimetric shiftsS andM:…”

“…Li and Berns [13] compared different methods of parameric correction for the evaluating of metamerism. The reliable approach for parameric correction was suggested using parameric decomposition based on principal component analysis [14].…”