Research On Color Space Conversion Algorithm Of Metamerism

Metamerism anti-counterfeiting technology is a new type of anti-counterfeiting technology.It has high anti-counterfeiting application value because of its excellent anti duplication,anti-counterfeiting,anti fouling and anti damage ability,and is fully compatible with various existing two-dimensional code,one-dimensional code and digimarc barcode technologies.At this stage,the main means to achieve metameric anti-counterfeiting technology is to use metameric ink.In order to make the metameric anti-counterfeiting technology have the advantages of low cost and simple production process,this paper only uses the common CMYK four-color ink,and uses the color space conversion algorithm to solve the problem that the metameric anti-counterfeiting technology needs special ink.In this paper,the basic research of color space conversion is carried out firstly.On the one hand,the principles and application fields of different color space conversion algorithms are analyzed.On the other hand,the principles,methods and key technologies of different color space conversion algorithms are analyzed,and the advantages and disadvantages of common color space conversion algorithms are compared.Secondly,the color space conversion based on polynomial regression algorithm is studied.Based on the traditional polynomial regression algorithm to realize rgb-cmyk color space conversion under the definition of k-tone,the polynomial regression algorithm is improved by using the method of color partition,which saves the cost,shortens the calculation time and improves the conversion accuracy.Finally,the color space conversion based on BP neural network algorithm is studied.BP neural network of Adam optimization algorithm is used to build rgb-cmyk color space conversion model under the definition of k-tone.The characteristics of polynomial regression algorithm and BP neural network are analyzed,and the advantages and disadvantages of the two algorithms in color space conversion are pointed out.In the model validation,through data comparison and pixel visual comparison,it is proved that the model meets the requirements of metamerism.The innovation of this paper is to build a high-precision color space conversion model under the definition of k-tone.Through the structure of 4-input and 3-output,the rgb-cmy color space conversion under the condition of k-tone or different k-tone under the condition of RGB is realized,and the metamerism data can be found easily and quickly.